Lipstick-type USB device with tubular housing

This application is continuation-in-part of U.S. patent application for “LIPSTICK-TYPE USB DEVICE”, U.S. application Ser. No. 12/505,327, filed on Jul. 17, 2009.

This application is also a CIP of U.S. patent application for “FLASH DRIVE WITH SPRING-LOADED RETRACTABLE CONNECTOR”, U.S. application Ser. No. 12/361,772, filed on Jan. 29, 2009.

This application is also a CIP of U.S. patent application for “Methods and Systems of Managing Memory Addresses in a Large Capacity Multi-Level Cell (MLC) based flash memory device”, U.S. application Ser. No. 12/025,706, filed Feb. 4, 2008.

This application is also a CIP of U.S. patent application for “Pen-Like Universal Serial Bus (USB) Flash Drive with Deploying and Retracting Functionalities”, U.S. application Ser. No. 11/950,190, filed Dec. 4, 2007.

This invention relates to portable electronic devices, and more particularly to portable electronic devices such as those that utilize the Universal-Serial-Bus (USB) specification.

In the past, confidential data files were stored in floppy disks or were delivered via networks that require passwords or that use encryption coding for security. Confidential documents can be sent by adding safety seals and impressions during delivering. However, the aforesaid are exposed to the risks of breaking of the passwords, encryption codes, safety seals and impressions, thereby resulting in unsecure transfer of information.

More recently, there is an ongoing trend towards the use of miniaturized, portable computer peripheral devices to store confidential data. In certain cases, such peripheral devices have been reduced to “pocket size”, meaning that they can literally be carried in a user's pocket in the same manner as a wallet or set of keys. One example of particular interest, in which context the present invention will be described herein, is a “flash disk”, “Universal Serial Bus (USB) flash drive”, or simply “USB device”.

USB flash drives are available in various shapes and forms. The USB flash drive uses a USB (male) plug connector to be coupled to a USB (female) plug socket (port) provided on a host device such as a PC. A problem associated with USB flash drives is that the USB (male) plug connector must be kept covered when not in use in order to prevent contamination of the contact pads, which would prevent the USB device from operating properly when plugged into a (female) plug socket connected to a host system. The USB flash drive generally includes a metal or plastic casing and a cap which is screwed or otherwise attached to the casing over the USB plug connector during transport (non-operation) periods. When operation of the USB flash drive is desired, the USB plug connector is accessed by removing the cap from the casing, thus exposing the plug connector for insertion into the host system port. When the desired operation is completed, the USB flash drive is pulled to extract the plug connector from the port, and then the cap is reattached onto the casing over the plug connector.

A problem with conventional removable-cap-type USB flash drives is that, once the cap is removed, it may be lost or forgotten, thereby exposing the plug connector to contamination or damage during subsequent transport periods, thereby risking failure of the USB flash drive and the loss of valuable information.

A conventional solution for the problem of keeping the plug connector clean during transport without using a detachable cap is to provide a USB device with a retractable plug connector in which an actuator is used to retract the plug connector into the device housing during transport, and to deploy (extend) the plug connector from an opening in the front of the housing for plugging into a host system during operation. Conventional USB devices that utilize retracting actuators are referred to as “pen-type” USB devices, and utilize a press-push (thumb-button) actuator accessible by way of a slot defined in a side or edge wall of the housing.

A problem with conventional pen-type USB devices is that the press-push actuator can become fouled or otherwise jam after repeated use, which can cause the actuator to become painful to operate, and may fail entirely, thereby causing the loss of valuable information.

What is needed is a retractable portable computer peripheral device that overcomes the problems associated with conventional retractable structures. What is particularly needed is a high quality retractable USB device that has a very low production cost, and provides a reliable deploying mechanism that allows a user to comfortably apply a significant actuating force.

The present invention is directed to a lipstick-type USB device (or other portable computer peripheral apparatus utilizing a lipstick-type actuator) including a rear cap assembly including a rear cap that is rotatably connected to a single-piece tubular housing, and an actuator portion that is operably engaged with a positioning structure disposed on an elongated positioning rod extending from the rear of a sliding rack assembly that is movably disposed in the tubular housing. With this arrangement, when the rear cap is manually rotated by a user around a longitudinal axis, the sliding rack assembly is caused to move along the longitudinal axis inside the tubular housing, thereby causing a plug connector disposed on a front end of the sliding rack assembly to move between a retracted position inside the tubular housing and a deployed position in which the plug connector is exposed outside a front opening of the tubular housing for operable coupling to a host system. The rear cap and tubular housing remain rotatably connected together at all times (i.e., such that the rear cap remains secured to the tubular housing (a) in a deployed position when the plug connector is extended through the front opening of the tubular housing to facilitate connection of the plug connector to a host system during operating periods, (b) in a retracted position when the plug connector is positioned inside the tubular housing when the USB device is not in use, and (c) during movement of the plug connector between the deployed and retracted positions), thereby preventing loss of the rear cap during operation.

According to one embodiment, the positioning structure includes a positioning knob that is disposed on the positioning rod, the actuator portion of the rear cap includes one of an oval cam surface and a spiral groove, and the positioning knob is operably engaged with the cam surface/spiral groove such that the positioning knob remains coupled to the actuator portion while the sliding rack assembly is slid between the retracted position and the deployed position. By providing such a lipstick-type actuating mechanism in which the plug connector is deployed and retracted by rotating a rear cap relative to the tubular housing, the present invention provides a convenient, reliable and easy to use retractable USB device that avoids fouling or jamming after repeated use by avoiding slots or other openings into the tubular housing, and thereby avoiding the loss of valuable information by preventing failure of the USB device to deploy. In addition, by utilizing a positioning rod that extends from the rear end of a sliding rack assembly and operably engages an actuating portion of the rear cap, the present invention provides a high quality retractable USB device that has a very low production cost, and provides a reliable deploying mechanism that allows a user to comfortably apply a significant actuating force.

According to an aspect of the invention, the rear cap handle structure includes opposing upper, lower and side walls that have the same shape and spacing as upper, lower and side walls of the tubular housing, and the actuating mechanism is disposed such that the upper and lower walls of the rear cap handle structure form a substantially continuous surface with the opposing upper and lower walls of the tubular housing when the plug connector is in both the fully deployed and fully retracted positions, thereby providing an aesthetically pleasing package that can be comfortably carried in a user's pocket. In one embodiment, both the tubular housing and the rear cap include planar walls that align to form substantially continuous co-planar surfaces when the plug connector is in both the fully deployed and fully retracted positions. In other embodiments, both the tubular housing and the rear cap include curved walls that form continuous curved surfaces when the plug connector is in both the fully deployed and fully retracted positions.

According to an aspect of the present invention, the rear cap assembly includes a “hidden” coupling structure (e.g., a snap ring) that serves to rotatably secure the rear cap handle structure to the tubular housing in an aesthetically pleasing manner. The coupling structure includes a flat wall having a peripheral edge that is sized to fit within a seat formed in the rear edge of the tubular housing such that the flat wall aligns with the rear edge to essentially close off the rear opening of the tubular housing. The coupling structure also includes several locking structures that protrude from the flat wall that fixedly engage with protrusions (first locking structures) disposed inside the central chamber, thereby fixedly connecting the coupling structure to the tubular housing. The flat wall defines a central opening and multiple radial slits extending radially outward from the central opening that facilitate insertion of a corresponding mounting structure disposed on a front portion of rear cap handle structure. That is, the radial slits allow portions of flat wall to temporarily bend inward when the mounting structure is pressed through the center opening, and when the mounting structure clears the central opening, these portions then resiliently return to the planar shape of the flat wall and engage with a bearing slot formed on the handle structure, whereby the rear cap handle structure is rotatably connected to the tubular housing by way of the coupling structure. Because the flat wall aligns with the rear edge of the tubular housing, the front edge of the rear cap handle structure can be positioned very close to the rear edge of the tubular housing (i.e., with a minimal gap), thereby further enhancing the substantially continuous surface formed by the tubular housing and the rear cap handle structure.

According to at least one specific embodiment of the present invention, the lipstick-type USB device further includes a spring (or other resilient member) that is disposed inside the tubular housing and operably arranged to bias the sliding movement sliding rack assembly along the longitudinal axis inside the tubular housing. In one specific embodiment, the spring is a coil spring disposed between a portion of the sliding rack assembly and the front portion of the tubular housing, and biases the sliding movement sliding rack assembly along the longitudinal axis toward the rear cap assembly. With this arrangement, the spring helps to maintain operable engagement between the actuator portion and the positioning structure, thereby providing a desirable “automatic retraction” feature that forces retraction of the plug connector into the tubular housing when the handle structure is rotated out of the deployed position.

According to specific embodiments of the present invention, a lipstick-type USB device includes a deploy/retract actuator constructed such that the rotatable cap is freely rotatable around the longitudinal axis relative to the tubular housing an unlimited number of full rotations in both the clockwise and counterclockwise directions. In particular, the deploy/retract actuator is constructed such that, when the rotatable cap is rotated in a clockwise/counterclockwise direction until the plug connector is fully retracted or fully deployed, further rotation of the clockwise/counterclockwise direction is not impeded, thereby preventing damage to the deploy/retract actuator mechanism caused by over-rotation of the rotating cap when the sliding rack assembly reaches the fully deployed or fully retracted positions inside the tubular housing.

According to a specific embodiment of the present invention, the actuator portion includes a substantially oval cam surface, and the rack assembly carrier includes one or more positioning knobs that are disposed on the positioning rod and operably engaged with the substantially oval cam surface. A spring (or other resilient member) is disposed inside the tubular housing, and serves to bias the sliding rack assembly toward the rear cap assembly, thereby maintaining the positioning knob in contact with the cam surface. In response to rotation of the rear cap handle structure, the substantially oval cam surface applies a force against the positioning knob that is transferred to the sliding rack assembly by the positioning rod. When rotation of the rear cap causes the positioning knob to slide on a forward slanting portion of the cam surface, the sliding rack assembly is pushed forward against the spring bias, and the plug connector is moved through the front opening into the deployed position in which the plug connector is exposed for operable coupling to a host system. When rotation of the rear cap causes the positioning knob to slide on a backward slanting portion of the cam surface, the spring bias pushes the sliding rack assembly toward the back of the tubular housing, thereby moving the plug connector into a retracted position in which said plug connector is fully retracted inside the tubular housing. This arrangement allows the cap to freely rotate around the longitudinal axis relative to the tubular housing an unlimited number of full rotations in both the clockwise and counterclockwise directions without worrying about applying a damaging torque to the actuating mechanism.

According to an aspect of the invention, locking grooves are provided on the substantially oval cam surface to conveniently hold the sliding rack mechanism in the fully deployed and fully retracted positions. In particular, the positioning knobs slide along the cam surface between a forward (first) locking groove that holds the USB device in the fully deployed position, and a rear (second) locking groove that holds the USB device in the fully retracted position. The locking grooves are formed such that a user must apply a relatively large force to the rear cap in order to displace the positioning knob out of the locking grooves, thereby preventing undesirable deploying or retraction of the plug connector.

According to alternative embodiments of the invention, the substantially oval cam surface of the actuator portion is either disposed on a mounting structure extending from the handle structure into the tubular housing, or formed on a mounting structure disposed inside a hollow region of the rear cap handle structure. In at least one specific embodiment, the actuator portion is integrally formed with the rear cap handle structure, and includes a hollow cylindrical wedge-shaped structure extending from the rear cap into the tubular housing, where the hollow cylindrical wedge-shaped mounting structure has a peripheral edge defining the substantially oval cam surface. In another specific embodiment, the actuator portion includes a separately molded rotary sleeve that is inserted inside hollow cylindrical mounting structure that is integrally molded inside rear cap handle structure. In these specific embodiments, the positioning knob disposed on the positioning rod extending from the rear end of the sliding rack assembly is pressed against the substantially oval cam surface by the spring, thereby facilitating reliable positioning of the plug connector.

According to another embodiment, a lipstick-type USB device similar to that described above is characterized in that the biasing spring utilized in the embodiments described above is omitted by providing an oval cam channel on an inside surface of the handle structure, and disposing the positioning knob inside the oval cam channel. In a specific embodiment, the rear cap assembly includes an upper handle portion having a first oval cam surface portion, and a lower handle portion having a second oval cam surface portion, the upper and lower handle portions being formed such that the oval cam channel is defined between the first and second oval cam surface portions when the upper handle portion is operably mounted onto the lower handle portion.

According to various alternative embodiments, the specific USB device packages described herein may be modified to house a conventional PCBA structure, a PCBA constructed using a chip-on-board (COB) process, or a PCBA constructed using a surface-mount technology (SMT) slim type PCBA process. The various structures may also be utilized to produce other types of portable computer peripheral apparatus, including one based on the Secure Digital (SD) standard, the Micro SD standard, the Multi-Media Card (MMC) standard, the Compact Flash (CF) standard, the Memory Stick (MS) standard, the PCI-Express standard, the Integrated Drive Electronics (IDE) standard, the Serial Advanced Technology Attachment (SATA) standard, the external SATA standard, the Radio Frequency Identification (RFID) standard, a fiber channel standard and an optical connection protocol standard.

These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings, where:

FIG. 1 includes sequential perspective views showing an exemplary USB device according to a generalized embodiment of the present invention during operation;

FIG. 2 is an exploded perspective view showing a USB device according to a first specific embodiment of the present invention;

FIGS. 3(A) , 3 (B), 3 (C) and 3 (D) are exploded perspective views showing the USB device of FIG. 2 during assembly;

FIG. 4 is a simplified cross-sectional side view showing a portion of the USB device of FIG. 2 ;

FIGS. 5(A) and 5(B) are partial perspective views showing the USB device of FIG. 2 during operation with the tubular housing removed for illustrative purposes;

FIG. 6 includes sequential perspective views showing the USB device of FIG. 2 during operation;

FIG. 7 is an exploded perspective view showing an exemplary USB device according to another specific embodiment of the present invention;

FIGS. 8(A) and 8(B) are perspective views showing a portion of the USB device of FIG. 7 during operation;

FIGS. 9(A) and 9(B) are assembled perspective views showing the USB device of FIG. 7 during operation;

FIG. 10 is an exploded perspective view showing an exemplary USB device according to another specific embodiment of the present invention;

FIGS. 11(A) , 11 (B) and 11 (C) are perspective views showing a rear cap assembly of the USB device of FIG. 10 during assembly;

FIG. 12 is an exploded perspective rear view showing the USB device of FIG. 10 during assembly;

FIGS. 13(A) and 13(B) are partial perspective views showing the USB device of FIG. 10 during operation with the tubular housing removed for illustrative purposes

FIG. 14 is an exploded perspective view showing an exemplary USB device according to another specific embodiment of the present invention;

FIGS. 15(A) and 15(B) are partial exploded perspective views showing a portion of the USB device of FIG. 14 ; and

FIG. 16 is an assembled perspective showing the USB device of FIG. 14 .

The present invention relates to an improvement in low-profile USB connectors. The following description is presented to enable one of ordinary skill in the art to make and use the invention as provided in the context of a particular application and its requirements. As used herein, directional terms such as “front”, “back” “upper”, “upwards”, “lower”, “side”, “upward” and “downward” are intended to provide relative positions for purposes of description, and are not intended to designate an absolute frame of reference. In addition, the term “integrally molded” is intended to mean that the subject items are formed together in a single molding process, as opposed to being formed separately and then connected, e.g., by adhesive. Various modifications to the preferred embodiment will be apparent to those with skill in the art, and the general principles defined herein may be applied to other embodiments. Therefore, the present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

FIG. 1 includes sequential perspective views showing an exemplary lipstick-type USB device (portable computer peripheral apparatus) 100 according to a generalized embodiment of the present invention. Referring to the left side of FIG. 1 , lipstick-type USB device 100 generally includes a single-piece tubular housing 110 , a sliding rack assembly 120 movably disposed in the housing, and a rear cap assembly 160 including a rear cap handle structure 161 that is rotatably connected to rear end portion of tubular housing 110 .

Referring to the lower right portion of FIG. 1 , tubular housing 110 is a molded plastic or folded metal box-like structure having a front end portion 111 defining a front opening 112 , opposing side walls 113 - 1 and 113 - 2 and opposing upper and lower walls 114 - 1 and 114 - 2 extending from front end portion 111 and defining an elongated central cavity 115 , and a substantially rectangular rear edge 116 that defines a rear opening 117 communicating with a back portion of central cavity 115 .

Referring to the upper left portion of FIG. 1 , sliding rack assembly 120 is disposed in tubular housing 110 such that sliding rack assembly 120 is slidable along a longitudinal axis Xextending through elongated central cavity 115 . Sliding rack assembly 120 generally includes a carrier 121 including a plastic carrier tray 122 and an elongated positioning rod 125 that extends from a rear portion of carrier tray 122 and is fixedly connected or integrally molded to a rear section of carrier tray 122 . One or more positioning structures 127 (e.g., a knob) are disposed on a rear portion of positioning rod 125 . At least one electronic device 140 is fixedly connected to the carrier (e.g., mounted on carrier tray 122 ), and a standard USB plug connector 150 is fixedly connected to a front end of carrier tray 122 . Referring again to the bottom right portion of FIG. 1 , plug connector 150 includes a substrate 151 having four of metal contacts 152 formed thereon, and a metal plug shell 155 that extends over substrate 151 . Metal contacts 152 are shaped and arranged in a pattern established by the USB specification, and are electronically coupled to electronic device 140 according to known techniques.

Referring to both the upper and lower portions of FIG. 1 , rear cap assembly 160 is connected to the rear edge of tubular housing 110 and includes a handle structure 161 that is disposed outside of tubular housing 110 (i.e., behind rear edge 116 ), and an actuator portion 165 that is disposed inside at least one of tubular housing 110 and handle structure 161 . Handle structure 161 includes a box-like structure formed by side walls 163 - 1 and 163 - 2 , upper wall 164 - 1 and lower wall 164 - 2 , and is rotatably connected to tubular housing 110 such that side walls 163 - 1 and 163 - 2 and upper and lower walls 164 - 1 and 164 - 2 cover rear edge 116 of housing 110 in the opened and closed positions respectively shown in the upper and lower portions of FIG. 1 . Actuator portion 165 is disposed either inside a space defined by side walls 163 - 1 and 163 - 2 and upper and lower walls 164 - 1 and 164 - 2 , or extends into central cavity 115 of tubular housing 110 .

According to an aspect of the present invention, actuator portion 165 is operably engaged with positioning structure 127 , which is disposed on positioning rod 125 , such that manual rotation of rear cap handle structure 161 relative to housing 110 around longitudinal axis X causes sliding rack assembly 120 to slide inside housing 110 between a retracted position, in which plug connector 150 is disposed inside of housing 110 (as shown in the upper left portion of FIG. 1 ), and a deployed position, in which plug connector 150 protrudes through and is exposed outside front opening 112 for operable coupling to a host system (as shown in the lower right portion of FIG. 1 ). As indicated in FIG. 1 , this operable engagement is achieved by causing the one or more positioning structures 127 disposed on positioning rod 125 to slide along a curved surface 167 (e.g., a curved cam surface or a spiral groove) disposed on actuator portion 165 . That is, the side and rectangular shape of sliding rack assembly 120 prevents its rotation inside tubular housing 110 when rear cap handle structure 161 is rotated relative to tubular housing 110 , and cam surface/spiral groove 167 is fixedly connected to rear cap handle structure 161 such that cam surface/spiral groove 167 turns around central axis X when cap handle structure 161 is rotated relative to tubular housing 110 . With this arrangement, rotation of rear cap handle structure 161 causes cam surface/spiral groove 167 to apply force on positioning rod 125 by way of positioning structure 127 , thereby causing sliding rack assembly 120 to slide within housing 110 . For example, USB device 100 is shown at the top left portion of FIG. 1 at a first time t 1 (indicated by reference designation “ 100 ( t 1 )”) in a fully retracted position (i.e., rear cap handle structure 161 is subject to 0° of rotation around longitudinal axis X), where positioning structures 127 engages a rearward portion of cam surface/spiral groove 167 . Subsequent rotation of rear cap handle structure 161 around longitudinal axis X by a predetermined amount (e.g., either 90° in a clockwise direction, as indicated by the solid-line arrow in the middle of FIG. 1 , or 90° in the counterclockwise direction, as indicated by the dashed-line arrow) while housing 110 maintained in a stationary position causes positioning structures 127 to slide onto a central portion of cam surface/spiral groove 167 , thereby causing actuator portion 165 to push positioning rod 125 (shown in the upper left portion of FIG. 1 ) toward front wall (end portion) 111 , whereby plug connector 150 partially protrudes through front opening 112 . Further rotation of rear cap handle structure 161 around longitudinal axis X (e.g., either 180° in a clockwise direction, as indicated by the solid-line arrow in the lower right portion of FIG. 1 , or 180° in the counterclockwise direction, as indicated by the dashed-line arrow) while housing 110 maintained in a stationary position causes positioning structures 127 to slide further onto a frontward portion of cam surface/spiral groove 167 , thereby causing actuator portion 165 to further push positioning rod 125 toward front wall 111 , whereby plug connector 150 is caused to fully deploy through front opening 112 . As described below, subsequent rotation of rear cap handle structure 161 relative to housing 110 in either the clockwise/counterclockwise direction is performed to retract plug connector 150 back into housing 110 . By providing such a lipstick-type actuating mechanism in which plug connector 150 is deployed and retracted by rotating rear cap handle structure 161 relative to housing 110 , the present invention provides a convenient, reliable and easy to use retractable USB device that avoids fouling or jamming after repeated use by avoiding slots or other openings into the housing that are present in conventional pen-type retractable devices, and thereby avoiding the loss of valuable information by preventing failure of the USB device to deploy. In addition, by utilizing positioning rod 125 and positioning structure 127 , which extends from the rear end of sliding rack assembly 120 and is operably engaged to cam surface/spiral groove 167 of actuating portion 165 , the present invention provides a high quality retractable USB device that has a very low production cost, and provides a reliable deploying mechanism that allows a user to comfortably apply a greater actuating force than is possible using a conventional pen-type actuating mechanism.

According to another aspect of the present invention, rear cap 160 and housing 110 remain rotatably connected together at all times (i.e., such that rear cap 160 remains secured to housing 110 (a) at time t 1 when plug connector 150 is in the retracted position shown at the upper left of FIG. 1 , (b) in the deployed position when plug connector 150 extends through front opening 112 as shown in the lower right portion of FIG. 1 , and (c) during movement of plug connector 150 between the deployed and retracted positions), thereby preventing loss of rear cap 160 during operation.

According to another aspect of the invention, the actuating mechanism is arranged such that rear cap 160 and housing 110 form substantially continuous surfaces when plug connector 150 is in the fully deployed and fully retracted positions. For example, as shown in the lower right portion of FIG. 1 , when plug connector 150 is in the fully deployed position, side walls 163 - 1 and 163 - 2 of handle structure 161 respectively align with side walls 113 - 1 and 113 - 2 , and opposing upper and lower walls 164 - 1 and 164 - 2 of handle structure 161 respectively align with upper/lower walls 114 - 1 and 114 - 2 of housing 110 . This arrangement provides USB device 100 with an aesthetically pleasing appearance and facilitates comfortable storage in a user's pocket.

Various specific embodiments of the present invention will now be described with reference to FIGS. 2-16 , where FIGS. 2-13 depict freely rotating embodiments of the present invention that utilize a biasing member (spring) to bias the sliding rack assembly inside the tubular housing, and FIGS. 14-17 describe another freely rotating embodiment of the present invention without using a spring to bias the sliding rack assembly. In the freely rotating embodiments, the actuator portion of the rear cap is engaged with positioning rod such that the rear cap handle structure is freely rotatable around the longitudinal axis relative to the housing, whereby the rear cap handle structure can be turned an unlimited number of full rotations in both the clockwise and counterclockwise directions relative to the tubular housing. In particular, the deploy/retract actuator is constructed such that, when the rotatable cap is rotated in a clockwise/counterclockwise direction until the plug connector is fully retracted or fully deployed, further rotation of the clockwise/counterclockwise direction is not impeded, thereby preventing damage to the deploy/retract actuator mechanism caused by over-rotation of the handle structure when the sliding rack assembly reaches the fully deployed or fully retracted positions inside the tubular housing.

FIG. 2 is an exploded perspective view showing a freely rotating lipstick-type USB device 100 A according to a first specific embodiment of the present invention. USB device 100 A generally includes a single-piece tubular housing 110 A, a sliding rack assembly 120 A, a rear cap assembly 160 A, and a spring 180 A.

Tubular housing 110 A is a single-piece molded plastic structure having front end portion 111 A that defines a front opening 112 A, opposing side walls 113 A- 1 and 113 A- 2 and opposing upper and lower walls 114 A- 1 and 114 A- 2 that extend from front end portion 111 A and defining an elongated central cavity portion 115 A, and a rear edge 116 A that surrounds and defines a rear opening 117 A. A rectangular seat (recess) 118 A is formed on a rear portion of tubular housing 110 A around rear edge 116 A for receiving a coupling structure (described below), and is shown in cross-section in FIG. 4 . Four protrusions (first locking structures) 119 A are disposed on an inside surface of tubular housing 110 A and extends into elongated inner chamber 115 A, and serves to secure the coupling structure in the manner described below.

Referring to the center of FIG. 2 , sliding rack assembly 120 A generally includes a carrier 121 A, a molded, single piece chip-on-board (COB) type PCBA 130 A, and an elongated metal connector plug shell 150 A. Carrier 121 A includes a plastic carrier tray 122 A and an elongated positioning rod 125 A that extends from a rear portion of carrier tray 122 A and is fixedly connected or integrally molded to a rear section of carrier tray 122 A. As described below, a positioning knob 127 A is provided on positioning rod 125 A to serve as part of an actuating mechanism. Carrier tray 122 A includes an upper tray portion 122 A- 1 and a lower tray portion 122 A- 2 that form a clip-like structure for receiving and securing PCBA 130 A. PCBA 130 A includes standard USB metal contacts 152 A formed on a first (e.g., upper) surface of a PCB, and IC components (e.g., flash memory chip 140 A) mounted on the opposite (e.g., lower) surface of the PCB. A molded casing is then mounted or otherwise formed over the IC components (i.e., over the lower surface of the PCBA). The casing has a planar surface that is parallel to the PCB and extends along the entire length of the PCBA (e.g., from a front edge of the plug structure to a rear edge of the PCB). Accordingly, PCBA 130 A is a flat, low-profile (thin) structure that can be easily incorporated into USB device 100 A, e.g., using carrier 121 A, by mounting PCBA 130 A between upper tray portion 122 A- 1 and lower tray portion 122 A- 2 of carrier tray 122 A. Plug connector 150 A is fixedly connected to a front end of carrier tray 122 A over PCBA 130 A such that metal contacts 152 A are exposed in a gap according to USB standards.

Referring to the right side of FIG. 2 , rear cap assembly 160 A includes a box-like rear cap handle structure 161 A similar that described above, and an actuator portion 165 A that is integrally molded with handle structure 161 A and includes a hollow cylindrical wedge-shaped mounting structure 166 A extending from handle structure 161 A. As described below, wedge-shaped structure 166 A includes a substantially oval cam surface 167 A that cooperates with positioning knob 127 A to serve as an actuating mechanism for deploying/retracting plug connector 150 A. Cam surface 167 A includes a front (first) locking groove 167 A- 1 and a rear (second) locking groove 167 A- 2 that serve to hold USB device 100 A in the fully deployed and fully retracted positions, respectively, in the manner descried below. Finally, a neck-like bearing (locking) slot 168 A is defined between hollow cylindrical wedge-shaped structure 166 A and the handle portion of rear cap 160 A, which serves to rotatably secure rear cap 160 A to the housing in the manner described below.

According to an aspect of the present invention, rear cap assembly 160 A further includes a “hidden” coupling structure (snap ring) 170 A that serves to rotatably secure rear cap handle structure 161 A to tubular housing 110 A. In particular, as indicated in FIG. 2 , coupling structure 170 A includes a flat wall 171 A defining a central opening 172 A, where the peripheral edge 174 A of flat wall 171 A is sized to fit into seat 118 A defined in tubular housing 110 A. In addition, four (second) locking structures 177 A protrude from rear wall 171 A. A peripheral edge of central opening 172 A is formed with a series of slits that allow a portion of flat wall 171 A to bend in order to facilitate insertion of mounting structure 166 A in the manner described below.

FIGS. 3(A) to 3(D) illustrate a simplified process for assembling USB device 100 A according to an embodiment of the present invention.

Referring to FIG. 3(A) , sliding rack assembly 120 A is assembled by mounting COB PCBA 130 A between upper tray portion 122 A- 1 and lower tray portion 122 A- 2 of carrier 121 A, and then this sub-assembly is inserted through a rear opening defined in plug connector 150 A until a coupling structure 129 A disposed on upper tray portion 122 A- 1 is received in a lock opening 159 A defined in plug connector 150 A.

Referring to FIG. 3(B) , rear cap assembly 160 A is foamed by aligning wedge-shaped mounting structure 166 A with central opening 172 A defined in flat wall 171 A, and then pushing handle structure 161 A against coupling structure 170 A. Because the flat wall 171 A defines several slits 173 A that extending radially outward from central opening 172 A, portions of flat wall 171 A temporarily bend inward (i.e., away from handle structure 161 A) when wedge-shaped mounting structure 166 A is pushed through the central opening 172 A, thereby facilitating insertion of a corresponding mounting structure 166 A disposed on a front portion of rear cap handle structure 161 A. That is, the radial slits 173 A allow temporary localized bending of flat wall 171 A during the insertion process, and when mounting structure 166 A clears the central opening, these portions then resiliently return to the planar shape of the flat wall 171 A and engage with a bearing slot 168 A formed on the handle structure, whereby the rear cap handle structure 161 A is rotatably connected to the tubular housing 110 A by way of the coupling structure 170 A.

Referring to FIG. 3(C) , positioning rod 125 A is inserted into a hollow cylindrical central region 169 A of wedge-shaped mounting structure 166 A, and spring 180 A is mounted over plug connector 150 A of sliding rack assembly 120 A until a rear end of spring 180 A contacts a wall structure 128 A that is integrally molded onto carrier 121 A of rear cap assembly 160 A. Note also that positioning knob 127 A contacts substantially oval cam surface 167 A when positioning rod 125 A is inserted into hollow cylindrical central region 169 A, thereby operably connecting sliding rack assembly 120 A with rear cap assembly 160 A. The completed sub-assembly formed by the operation shown in FIG. 3(C) is indicated on the right side of FIG. 3(D) ).

Referring to FIGS. 3(D) and 4 , the sub-assembly including sliding rack assembly 120 A, spring 180 A and rear cap assembly 160 A are then inserted into tubular housing 110 A through rear opening 117 A until protrusions (first locking structures) 119 A extending from inside surfaces of upper/lower walls 114 A- 1 and 114 A- 2 into central cavity 115 A are snap-coupled into corresponding openings formed in (second) locking structures 177 A, as shown in FIG. 4 , thereby connecting rear cap assembly 160 A to tubular housing 110 A. Note that, upon assembly, spring 180 A is maintained in position to bias sliding rack assembly 120 A toward rear cap assembly 160 A because the front end of spring 180 A is held by front end portion 111 A (i.e., the front end of spring 180 A is too large to fit through front opening 112 A), and the rear end of spring 180 A is held by a wall structure 128 A. Referring to FIG. 4 , peripheral edge 174 A of flat wall 171 A of coupling structure 170 A is sized to fit within seat 118 A such that flat wall 171 A aligns with rear edge 116 A to essentially close off the rear opening 117 A (indicated by dashed line) of tubular housing 110 A. Note again that the peripheral edge of central opening 172 A is engaged in bearing slot 168 A such that handle structure 161 A is rotatably connected to coupling structure 170 A, and that mounting structure 166 A extends into central cavity 115 A of housing 110 A. In addition, positioning rod 125 A extends through the opening formed in mounting structure 166 A and into a hollow region formed in handle structure 161 A, with positioning knob 127 A pressed against cam surface 167 A.

FIGS. 5(A) and 5(B) are partial perspective views showing USB device 100 A with the tubular housing portion removed to better illustrate its operation. According to the present invention, actuator portion 165 A is operably engaged with positioning rod 125 A such that manual rotation of rear cap handle structure 161 A relative to housing 110 A causes sliding rack assembly 120 A to slide inside housing 110 A between the deployed position shown in FIG. 5(A) and the retracted position shown in FIG. 5(B) . According to an aspect of the present embodiment, this actuation is achieved by contact between positioning knob 127 A, which is fixedly mounted or integrally molded onto positioning rod 125 A, and substantially oval cam surface 167 A formed on hollow cylindrical wedge-shaped mounting structure 166 A, which slidably extends through central opening 173 A of coupling structure 170 A. Note that spring 180 A serves to bias sliding rack assembly 120 rearward (i.e., toward rear cap assembly 160 A), whereby positioning knob 127 A is maintained in reliable contact with cam surface 167 A. Note also that, as indicated in FIG. 5(A) , when handle structure 161 A is rotated to push plug connector 150 A into the deployed position, positioning knob 127 A enters and is secured in front locking groove 167 A- 1 , thereby maintaining the deployed position until the user applies sufficient torque to force positioning knob 127 A out of front locking groove 167 A- 1 against the bias of spring 180 A. Spring 180 A thus biases positioning knob 127 A into rear locking groove 167 A- 2 , whereby USB device 100 A is maintained in the retracted position until the user applies sufficient torque to force positioning knob 127 A back into front locking groove 167 A- 1 against the bias of spring 180 A.

FIG. 6 includes sequential perspective views showing USB device 100 A during operation. As described with reference to FIGS. 5(A) and 5(B) , the actuating mechanism of USB device 100 A facilitates free rotation of rear cap handle structure 161 A around longitudinal axis X relative to the housing 110 A, whereby handle structure 161 A can be turned an unlimited number of full rotations in both the clockwise and counterclockwise directions relative to the housing. For example, as illustrated in FIG. 6 , USB device 100 A(t 1 ) is in the fully retracted position (i.e., handle structure 161 A is subject to 0° of rotation around longitudinal axis X). Subsequent rotation of handle structure 161 A around longitudinal axis X by a predetermined amount (e.g., 90°, as indicated by USB device 100 A(t 2 ) in FIG. 6 ) while housing 110 A maintained in a stationary position causes the actuator portion 165 A to push positioning rod 125 A by way of contact between cam surface 167 A and positioning knob 127 A (shown in FIG. 5(B) ) toward front end portion 111 A, thereby causing plug connector 150 A to partially protrude through front opening 112 A. Further rotation of handle structure 161 A around longitudinal axis X (e.g., 180°, as indicated by USB device 100 A(t 3 ) in the center of FIG. 6 ) while housing 110 A maintained in a stationary position causes actuator portion 165 A to further push positioning rod 125 A forward, thereby causing positioning knob 127 A to enter front locking groove 167 A- 1 , as shown in FIG. 5(A) , whereby plug connector 150 A is maintained in the fully deployed position. According to the present embodiment, subsequent rotation of handle structure 161 A around longitudinal axis X (e.g., 270°, as indicated by USB device 100 A(t 4 ) in FIG. 6 ) while housing 110 A maintained in a stationary position causes positioning knob 127 A to detach from front locking groove 167 A- 1 (see FIG. 5 (A)), which causes spring 180 A to push sliding rack assembly 120 A back toward handle structure 161 A. Finally, when rotation of handle structure 161 A around longitudinal axis X completes a circle (e.g., 360°, as indicated by USB device 100 A(t 5 ) in FIG. 6 ), positioning knob 127 A reaches rear locking groove 167 A- 2 (see FIG. 5 (B)), which causes spring 180 A to settle in the fully retracted position. As described above, the deploy/retract actuating mechanism is constructed such that, when handle structure 161 A is rotated in a clockwise/counterclockwise direction until the plug connector is fully retracted or fully deployed, further rotation of the clockwise/counterclockwise direction is not impeded, thereby preventing damage to the deploy/retract actuator mechanism caused by over-rotation of handle structure 161 A when sliding rack assembly 120 A reaches the fully deployed or fully retracted positions inside housing 110 A.

FIG. 7 is an exploded perspective view showing a freely rotating lipstick-type USB device 100 B according to a second specific embodiment of the present invention. USB device 100 B generally includes a housing 110 B, a sliding rack assembly 120 B, a spring 180 B, and a rear cap assembly 160 B. Similar to USB device 100 A, sliding rack assembly 120 B includes a carrier 121 B that is slidably mounted inside tubular housing portion 110 B and biased toward rear cap assembly 160 B by spring 180 B. Further, rear cap assembly 160 B includes a handle structure 161 B that is connected to housing 110 B by way of a coupling structure 170 B in a manner similar to that described above. In addition, carrier 121 B of sliding rack assembly 120 B includes a positioning rod 125 B having a positioning knob 127 B that is pressed against a substantially oval cam surface formed on rear cap handle portion 161 B in the manner described above to deploy/retract a plug connector 150 CB, which is disposed on the front end of sliding rack assembly 120 B.

According to an aspect of the present embodiment, USB device 100 B differs from USB device 100 A in that sliding rack assembly 120 B includes a standard printed circuit board assembly (PCBA) 130 B in which various electronic devices (e.g., memory device 140 B) are mounted onto a standard printed circuit board (PCB) 131 B, and plug connector 150 B is connected to a front end of PCB 131 B using known techniques. In addition, carrier 121 B includes integrally molded features that serve as an alignment and locking mechanism for securing PCBA 130 B onto a lower wall 124 B of carrier 121 B, as shown in FIG. 8(A) , such that PCBA 130 B is prevented from contacting spring 180 B during assembly with rear cap assembly 160 B. The sub-assembly shown in FIG. 8(B) including sliding rack assembly 120 B, rear cap assembly 160 B and spring 180 B is then mounted inside tubular housing 110 B (shown in FIG. 7 ) in a manner similar to that described above with reference to USB device 100 A.

According to another aspect of the present embodiment, tubular housing 110 B and handle portion 161 B include matching outer wall surfaces that form continuous curved surfaces when plug connector 150 B is in either of the fully deployed and fully retracted positions. Referring to FIG. 7 , tubular housing 110 B includes opposing upper and lower walls 114 B- 1 and 114 B- 2 that are respectively curved slightly outward, and handle structure 161 B includes opposing upper and lower walls 164 B- 1 and 164 B- 2 whose curved shape matches that of tubular housing 110 B. For example, as indicated in FIGS. 9(A) and 9(B) , upper wall 114 B- 1 of housing 110 B forms a continuous curved surface with upper wall 164 B- 1 of handle structure 161 B when plug connector 150 B is in either of the fully retracted position (shown in FIG. 9(A) ) or the fully deployed position (shown in FIG. 9(B) ). The outward curvature of the upper and lower walls of device 100 B increases the structural strength of tubular housing 110 B (e.g., its resistance to a crushing pressure) over the flat-walled design of the first embodiment, thus extending the average product life and facilitating lower manufacturing costs by utilizing less plastic. Referring again to FIG. 7 , note that the outer shape of coupling structure 170 B is also modified to match the curved shapes of upper and lower walls 164 B- 1 and 164 B- 2 of tubular housing 110 B.

FIG. 10 is an exploded perspective view showing a freely rotating lipstick-type USB device 100 C according to a third specific embodiment of the present invention. USB device 100 C generally includes a tubular housing 110 C, a sliding rack assembly 120 C, and a spring 180 C that are similar to that of the second embodiment. Similar to the USB device 100 B, sliding rack assembly 120 C includes a standard PCBA disposed on a carrier 121 C that is slidably mounted inside tubular housing 110 C, and is biased toward rear cap assembly 160 C by spring 180 C. In addition, carrier 121 C has an integral positioning rod 125 C including a positioning knob 127 C that is biased against rear cap assembly 160 C in the manner described above to deploy/retract a plug connector 150 C, which is disposed on the front end of sliding rack assembly 120 C.

Similar to the previously described embodiments, rear cap assembly 160 C includes a handle structure 161 C and a coupling structure 170 C. However, according to an aspect of the present embodiment, USB device 100 C differs from the previously described USB devices in that rear cap assembly 160 C also includes a separately molded rotary sleeve 166 C- 2 that is snap-coupled inside a hollow cylindrical mounting structure 166 C- 1 , which is integrally molded to and disposed inside handle structure 161 C. With this arrangement, as indicated in FIG. 11(A) , actuator portion 165 C is formed by both hollow cylindrical mounting structure 166 C- 1 , which includes a first cam surface portion 167 C- 1 similar to that described above formed on an inside surface thereof, and rotary sleeve 166 C- 2 , which includes a second cam surface portion 167 C- 2 that serves to reliably guide positioning rod 125 C (e.g., to prevent positioning rod 125 C from swinging) during rotation of rear cap handle portion 161 C relative to housing 110 C.

FIGS. 11(A) to 11(C) illustrate the assembly of rear cap assembly 160 C. Referring to FIG. 11(A) , rotary sleeve 166 C- 2 is inserted into a hollow cylindrical central region 169 C defined by mounting structure 166 C- 1 until tabs 168 C- 2 are snap-coupled into corresponding notches 168 C- 1 defined at a front portion of mounting structure 166 C- 1 , thereby securing rotary sleeve 166 C- 2 to handle structure 161 C. Referring to FIG. 11(B) , with rotary sleeve 166 C- 2 inserted into hollow cylindrical central region 169 C, the front portion of mounting structure 166 C- 1 is inserted into central opening 172 C until locking ribs 168 C- 3 pass entirely through flat wall 171 C, whereby portions of flat wall 171 C resiliently return to their original planar shape to rotatably secure rotary sleeve 166 C- 2 to handle structure 161 C, as shown in FIG. 11(C) . The completed rear cap assembly 160 C shown in FIG. 11(C) is then ready for connection to the tubular housing by way of locking structures 177 C in the manner described above.

FIG. 12 is a rear top perspective view depicting the insertion of the sub-assembly including sliding rack assembly 120 C and spring 180 C through rear opening 117 C of tubular housing 110 C, and the subsequent connection of rear cap assembly 160 C onto rear edge 116 C of tubular housing 110 C. FIG. 12 shows two of the four locking structures 119 C disposed on the inside surface of tubular housing 110 C that engage with locking structures 177 C to complete the assembly process in a manner similar to that described in the embodiments above.

FIGS. 13(A) and 13(B) are partial perspective views showing portions of USB device 100 C with the tubular housing removed to better illustrate the device operation. As illustrated in FIGS. 13(A) and 13(B) , substantially oval cam surface 167 C- 1 serves to position sliding rack assembly 120 C in a manner similar to that described above with reference to USB device 100 A, wherein positioning knob 127 C slides along cam surface 167 C- 1 inside rear cap handle structure 161 C in response to rotation of handle structure 161 C relative to the housing (not shown), thereby positioning sliding rack assembly 120 C by way of positioning rod 125 C. Note that substantially oval cam surface 167 C- 1 includes a front locking groove that receives positioning knob 127 C to maintain plug connector 150 C in the deployed position (see FIG. 13(A) ) and a rear locking groove that maintains plug connector 150 C in the retracted position (see FIG. 13(B) ) in the manner described above. An advantage of this embodiment is that the overall length of USB device 100 C may be made shorter than that of the previous embodiments.

FIG. 14 is an exploded perspective view showing a freely rotating lipstick-type USB device 100 D according to a fourth specific embodiment of the present invention. USB device 100 D generally includes a tubular housing 110 D, a sliding rack assembly 120 D, and a rear cap assembly 160 D. Similar to the USB device 100 C, sliding rack assembly 120 D includes a standard PCBA and is slidably mounted inside tubular housing 110 D. In addition, sliding rack assembly 120 D includes a carrier tray 121 D having a positioning rod 125 D including a positioning knob 127 D that is engaged inside rear cap assembly 160 D in a manner similar to that described above with reference to device 100 C to deploy/retract a plug connector 150 D, which is disposed on the front end of sliding rack assembly 120 C.

According to an aspect of the present embodiment, USB device 100 D differs from the previously described USB devices in that it does not utilize a spring to bias sliding rack assembly 120 D in the manner described above. Instead, USB device 100 D is characterized in that rear cap assembly 160 D includes, in addition to a coupling structure 170 D similar to that described above, a two-part handle structure 161 D that forms an oval cam channel in which positioning knob 127 D is restricted to reside during the deploying and retracting operations. In particular, two-part handle structure 161 D includes an upper (first) handle portion 161 D- 1 and a lower (second) handle portion 161 D- 2 . Upper handle portion 161 D- 1 includes upper wall 164 D- 1 and side wall portions 163 D- 11 and 163 D- 21 , and lower handle portion 161 D- 2 includes lower wall 164 D- 2 and side wall portions 163 D- 12 and 163 D- 22 , where these wall portions are shaped and sized such that they form a box-like enclosure similar to that described above when operably connected. In addition, upper handle portion 161 D- 1 includes a first actuator portion 165 D- 1 having a first hollow semi-cylindrical structure portion 166 D- 1 including a first cam surface portion 167 D- 1 formed thereon, and lower handle portion 161 D- 2 includes a second actuator portion 165 D- 2 having a second hollow semi-cylindrical structure portion 166 D- 2 including a second cam surface portion 167 D- 2 formed thereon. Upper handle portion 161 D- 1 and lower handle portion 161 D- 2 are formed such that, when operably mounted on each other, a substantially uniform gap separating the cam surface portions 167 D- 1 and 167 D- 2 forms the oval cam channel used to slidably push/pull positioning knob 127 D when two-part handle structure 161 D is rotated relative to tubular housing 110 D during the deploying and retracting operations. That is, instead of using a spring to bias positioning knob 127 D against a single cam surface, a pushing force is applied to positioning knob 127 D during the deploying operation by one of cam surface portions 167 D- 1 and 167 D- 2 , and a pulling force is applied to positioning knob 127 D during the retracting operation by the other of cam surface portions 167 D- 1 and 167 D- 2 .

FIG. 15(A) illustrates a portion of the process utilized to assemble USB device 100 D according to an embodiment of the present invention. First, sliding rack assembly 120 D is assembled in a manner similar to that utilized in the previously described embodiments (e.g., by snap-coupling connecting PCBA 130 D to carrier 121 D by way of fasteners 128 D and 129 D, as shown). Next, coupling structure 170 D is positioned next to lower handle portion 161 D- 2 such that a neck-liked locking rib 168 D- 2 is located adjacent to opening 172 D. Next, sliding rack assembly 120 D is mounted on lower handle portion 161 D- 2 such that rod 125 D extends through opening 172 D and positioning knob 127 D is disposed over lower handle portion 161 D- 2 . Next, upper handle portion 161 D- 1 is mounted onto lower handle portion 161 D- 2 such that snap-coupling structures formed on upper handle portion 161 D- 1 are engaged with corresponding snap coupling structures disposed on lower handle portion 161 D- 2 in the manner indicated in FIG. 16 . The front ends of semi-cylindrical structure portions 166 D- 1 and 166 D- 2 are then inserted into opening 172 D to secure upper handle portion 161 D- 1 and lower handle portion 161 D- 2 to coupling structure 170 D in a manner similar to that described above. Finally, the sub-assembly shown in FIG. 15(A) is inserted into tubular housing 110 D using the methods described above to provide the fully assembled USB device 110 D shown in FIG. 16 .

FIG. 15(B) shows the same structures included in FIG. 15(A) , but depicts an alternative assembly process in which coupling structure 170 D is connected to upper handle portion 161 D- 1 , then sliding rack assembly 120 D is mounted such that positioning knob 127 D is disposed between opposing curved portions of second actuator portion 165 D- 2 , and then lower handle portion 161 D- 2 is snap-coupled onto upper handle portion 161 D- 1 in the manner described above. FIG. 15(B) also differs from FIG. 15(A) in that FIG. 15(B) shows the position of positioning knob 127 D after the handle structure is rotated 180° from the position shown in FIG. 15(A) (i.e., FIG. 15(A) shows the position of rod 125 D when sliding rack assembly 120 D is in the deployed position, and FIG. 15(B) shows the position of rod 125 D when sliding rack assembly 120 D is in the retracted position). Note that FIGS. 15(A) and 15(B) respectively show cam surface portions 167 D- 1 and 167 D- 2 , and in particular exemplary surface shapes that produce the desired oval cam channel used to slidably push/pull positioning knob 127 D when two-part handle structure 161 D is rotated relative to tubular housing 110 D during the deploying and retracting operations.

Although the present invention has been described with respect to certain specific embodiments, it will be clear to those skilled in the art that the inventive features of the present invention are applicable to other embodiments as well, all of which are intended to fall within the scope of the present invention. For example, those skilled in the art will recognize that each of USB devices may be modified to implement other PCBA types (e.g., surface mount technology (SMT)-type USB PCBAs). In addition, the various device structures may be modified to implement other types of portable computer peripheral apparatus, for example, by modifying the plug connector to include an interface circuit and plug structure that supports Secure Digital (SD), Micro SD, Multi-Media Card (MMC), Compact Flash (CF), Memory Stick (MS), PCI-Express, a Integrated Drive Electronics (IDE), Serial Advanced Technology Attachment (SATA), external SATA, Radio Frequency Identification (RFID), fiber channel and optical connection protocols. Also, the tubular housing structure is not limited to an integrally molded tubular housing structure, but may comprise a two-part housing assembly (e.g., including a top housing and bottom housing) that are fixedly connected to each other by a snap coupling mechanism or ultrasonic welding around edges of top and bottom housing.