Method for manufacturing liquid supply member

The present invention relates to a method for manufacturing a liquid supply member for a liquid ejection apparatus, such as an inkjet printing apparatus, and more particularly, to a manufacturing method which molds and assembles a plurality of components of a liquid supply member in a mold.

Japanese Patent Laid-Open No. 2002-178538 discloses this kind of manufacturing method. In the method, for example, two components forming a hollow body are formed at different positions in the same mold by injection molding (primary molding). After the mold is opened, one mold which holds one of the two components slides to a position where the two components come into contact with each other, relative to the other mold holding the other component. Then, the mold is closed so that the two components come into contact with each other to form the hollow body. In addition, a molten resin flows to a contact portion to join and seal the contact portion, thereby forming a sealed hollow component (secondary molding). According to this technique, it is possible to simply manufacture a liquid supply member.

However, the manufacturing method using a mold disclosed in Japanese Patent Laid-Open No. 2002-178538 has the problem that, when the contact portion between the two components is located at a deep position in one of the components, a mold opening stroke increases.

FIGS. 11A and 11B are diagrams illustrating a case in which two components 500 and 521 come into contact with each other at a shallow position and a case in which the two components H 500 and H 521 come into contact with each other at a deep position, respectively. In FIGS. 11A and 11B , a mold is not illustrated and only the two components are illustrated. Respective molds (not illustrated) which hold the components are opened upward and downward in FIGS. 11A and 11B . As illustrated in FIG. 11B , when the contact portion between the two components is located at a deep position in one of the two components, a mold opening stroke corresponding to a distance A 9 that is greater than a distance A 8 when the contact portion is located at a shallow position is required in order to open the molds and to slide the molds relative to each other.

As such, when the mold opening stroke is large, for example, the following problems also arise. When mass production is considered in injection molding, a hot runner system is generally used as an injection nozzle structure in order to prevent the manufacture of an unnecessary molded portion which is a defective product such as a runner portion. More specifically, the hot runner system allows a hot runner gate valve to be arranged closest to a molding product, and thus it is possible to perform molding such that a runner portion, which is unnecessary as a product after molding, is not formed. However, it is necessary to arrange a gate valve and a valve driving cylinder in the thickness direction of the mold for constructing the mold using the hot runner system, which results in an increase in the thickness of the mold. In addition, when the extraction of a molded product is automated, the work space of a robot for extracting the molded product is required as a mold opening space. From these points, when the mold opening stoke is relatively large, a large mold attachment space is required in the molding machine used. That is, the sizes of a mold and a molding machine and costs increase.

An object of the invention is to provide a liquid supply member manufacturing method which can suppress an increase in the size of a mold or a molding machine even in a molding process using a mold in which a contact portion between two components is located at a deep position in one of the two components.

In a first aspect of the present invention, there is provided a manufacturing method for molding a liquid supply member by using a first mold and a second mold which are capable of opened and closed relative to each other and in which the first mold is capable of being slid relatively to the second mold, the method comprising: a first molding step of performing injection molding to form a first component part of the liquid supply member and a second component part of the liquid supply member other than the first component part at different positions from each other, with the first and the second mold closed relative to each other; an evacuating step of sliding the formed second component part in a direction intersecting with a direction of sliding of the first mold relative to the second mold and with a direction of the opening and the closing the first and the second mold; a contacting step of sliding the first mold relative to the second mold and bringing the formed second component part into contact with the molded first component part; and a second molding step of performing injection molding to join the first component part and the second component part with the first and the second mold closed relative to each other.

According to the above-mentioned structure, in the liquid supply member manufacturing method, it is possible to suppress an increase in the size of a mold or a molding machine even in a molding process using a mold in which a contact portion between two components is located at a deep position in one of the two components.

Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).

FIGS. 1A and 1B are perspective views illustrating a print head used in an inkjet printing apparatus which is an embodiment of a liquid ejection apparatus according to the invention;

FIG. 2 is an exploded perspective view illustrating the detailed structure of a liquid supply member illustrated in FIGS. 1A and 1B ;

FIG. 3 is an exploded perspective view illustrating members forming a liquid chamber in the liquid supply member illustrated in FIGS. 1A and 1B ;

FIGS. 4A and 4B are a cross-sectional view and an enlarged view illustrating the structure of the liquid chamber in the liquid supply member illustrated in FIGS. 1A and 1B ;

FIG. 5 is a perspective view illustrating a mold according to an embodiment of the invention;

FIGS. 6A to 6C are diagrams illustrating the molding positions and shape pieces of the liquid supply member and a liquid chamber cover member H 121 in the mold according to the embodiment of the invention;

FIGS. 7A to 7C are diagrams illustrating the operation of the mold according to the embodiment of the invention;

FIGS. 8A to 8C are diagrams illustrating the operation of the mold according to the embodiment of the invention;

FIGS. 9A and 9B are cross-sectional views schematically illustrating the arrangement position of a valve gate for injecting a molding material for sealing a contact portion between two components;

FIGS. 10A and 10B are perspective views illustrating a liquid supply member according to another embodiment of the invention; and

FIGS. 11A and 11B are diagrams illustrating a case in which two components come into contact with each other at a shallow position and a case in which the two components come into contact with each other at a deep position during the molding of the two components using a mold, respectively.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIGS. 1A and 1B are perspective views illustrating a print head used in an inkjet printing apparatus which is an embodiment of a liquid ejection apparatus according to the invention, as viewed from different angles. In FIGS. 1A and 1B , a print head H 001 includes a sub-tank H 030 which is provided in an upper part in FIGS. 1A and 1B and into which a liquid supplied from a container (not illustrated) that stores ink as the liquid is introduced through, for example, a tube (not illustrated) connected to a liquid inlet H 010 . In addition, the print head H 001 includes a printing element unit H 020 which ejects the liquid onto a print medium and is provided on a surface facing downward in FIGS. 1A and 1B . The print head H 001 further includes a liquid supply member H 100 which is connected to the sub-tank H 030 and the printing element unit H 020 and forms a liquid supply path.

FIG. 2 is an exploded perspective view illustrating the detailed structure of the liquid supply member H 100 . The liquid supply path in the liquid supply member H 100 includes a filter H 101 which is provided in a portion connected to the sub-tank H 030 and removes foreign materials in the liquid introduced from the sub-tank. In the liquid supply path, a liquid chamber (flow path) H 110 which temporarily contains the liquid is provided on the downstream side of the filter H 101 . In addition, the printing element unit H 020 is connected to the downstream side of the liquid supply path.

As illustrated in FIG. 3 , the liquid chamber H 110 has an opening which is a connection portion with the filter H 101 and an opening which is a connection portion with the printing element unit H 020 . An opening which is positioned in a direction different from the directions in which the above two openings are formed is closed by a liquid chamber cover member H 121 .

FIGS. 4A and 4B are a cross-sectional view and an enlarged view illustrating the structure of the liquid chamber H 110 in the liquid supply member H 100 , respectively. FIG. 4A illustrates a cross section taken along the line S 1 -S 1 of FIG. 1B . A liquid, such as ink, is introduced from the sub-tank H 030 (not illustrated) through the filter H 101 connected to the sub-tank H 030 and is temporarily contained in the liquid chamber H 110 . The contained liquid is supplied to the printing element unit H 020 by an ejection operation in the printing element unit H 020 .

In this embodiment, the liquid supply member H 100 forming the liquid chamber H 110 is manufactured as a resin mold component by injection molding. In the injection molding, as illustrated in FIG. 4A , in the case that the positions or shapes of the opening on the side of the filter H 101 and the opening on the side of the printing element unit H 020 are different from each other and two openings are formed by combinations of complicated sides, an opening is further provided on another side. Then, after the liquid chamber H 110 is formed by injection molding, the opening is closed by the liquid chamber cover member H 121 which is another member. As such, in this embodiment, when the liquid supply member H 100 is formed by injection molding, two members, that is, the liquid supply member H 100 (a portion other than the liquid chamber cover member H 121 ) and the liquid chamber cover member H 121 are molded and come into contact with each other. Then, since the liquid chamber cover member H 121 is provided in one opening portion of the liquid chamber H 110 in the liquid supply member H 100 , it is formed in a deep portion of the structure of the liquid supply member H 100 in the injection molding.

Next, a method for manufacturing the liquid supply member H 100 using the injection molding according to an embodiment of the invention will be described.

FIG. 5 is a perspective view illustrating a mold according to an embodiment of the invention. A mold K 001 of this embodiment includes a stationary mold K 100 and a movable mold K 200 . The movable mold K 200 is provided with a die slide K 230 . The stationary mold K 100 and the movable mold K 200 are configured so as to be opened and closed for mold opening and mold clamping. The movable mold K 200 is configured so as to slide relative to the stationary mold K 100 . In the mold K 001 , a shape piece for molding the liquid supply member H 100 and a shape pieces for molding the liquid chamber cover member H 121 are arranged in the stationary mold K 100 or the movable mold K 200 . In FIG. 5 , reference numerals K 110 , K 111 , K 120 , K 130 , and K 131 indicate valve gates for injecting a resin.

FIGS. 6A to 6C are diagrams illustrating the molding positions and shape pieces of the liquid supply member H 100 and the liquid chamber cover member H 121 in the mold. FIG. 6A is a diagram as viewed along a z direction in FIG. 5 and illustrates the stationary mold K 100 in a see-through manner for ease of understanding of the inside of the mold. FIG. 6B is a diagram illustrating a cross section at a first molding position K 210 taken along the line S 3 -S 3 of FIG. 6A , and FIG. 6C is a diagram illustrating a cross section at a second molding position K 220 and a third molding position K 225 taken along the line S 4 -S 4 . FIGS. 6B and 6C illustrate the cross-sectional structures of the valve gates at each molding position.

In FIGS. 6A to 6C , the mold K 001 includes the first molding position K 210 at which the liquid supply member H 100 is molded, the second molding position K 220 at which the liquid chamber cover member H 121 is molded, and the third molding position K 225 at which the members are contacted and joined with each other. The valve gate K 110 , K 111 , K 120 , K 130 , or K 131 for injecting a molding material is provided at each molding position. The shape piece of the liquid supply member H 100 molded at the first molding position K 210 is made by the movable mold K 200 and the stationary mold K 100 . In addition, the shape piece of the liquid chamber cover member H 121 molded at the second molding position K 220 is made by a part piece K 222 and a part slide piece K 221 .

FIGS. 7A to 7C and FIGS. 8A to 8C are diagrams illustrating the operation of the mold according to an embodiment of the invention and sequentially illustrate the operation of the mold according to this embodiment for one cycle. In the drawings, the stationary mold is not illustrated for simplicity of illustration and explanation.

In the process illustrated in FIG. 7A , with the stationary mold (not illustrated) and the movable mold K 200 clamped, the liquid supply member H 100 and the liquid chamber cover member H 121 are formed at the first molding position K 210 and the second molding position K 220 by injection molding, respectively (primary molding). Two valve gates K 110 and K 111 for injection are provided at the molding position of the liquid supply member H 100 and one valve gate K 120 is provided at the molding position of the liquid chamber cover member H 121 . A portion other than the liquid chamber cover member H 121 , which is a first component of the liquid supply member H 100 , and the liquid chamber cover member H 121 , which is a second component other than the first component in the liquid supply member, are formed at different positions by injection molding. After molding is performed by this process, the mold is opened.

Then, in the process illustrated in FIG. 7B , with the molded liquid chamber cover member H 121 held by the part slide piece K 221 , the part slide piece K 221 is slid in the direction of an arrow A 2 in FIG. 7B by a part slide mechanism (not illustrated) having a driving mechanism different from a mold opening and clamping mechanism. That is, the part slide piece is slid in the direction of the arrow A 2 which intersects (in this embodiment, the direction perpendicular to) a direction in which the mold K 100 and the mold K 200 are opened and a die slide direction which will be described below. This slide allows the molded liquid chamber cover member H 121 to be evacuated from the path of die sliding performed in the subsequent process. As described above, the liquid chamber cover member H 121 is provided in a relatively deep portion of the structure of the liquid supply member H 100 . In the molding method according to this embodiment, the liquid chamber cover member H 121 is not evacuated by an operation of opening the movable mold and the stationary mold, but is evacuated by sliding in the direction of the arrow A 2 . In this way, it is not necessary to increase the stroke of the operation of opening the movable mold and the stationary mold.

Here, in order to move out the molded liquid chamber cover member H 121 with the sliding of the part slide piece K 221 , the force of the part slide piece K 221 holding the surface of the liquid chamber cover member H 121 which faces the part slide piece K 221 needs to be stronger than the force of the part piece K 222 holding the opposite surface of the liquid chamber cover member H 121 . Therefore, a plurality of sleeve structures H 122 ( FIG. 4B ) are provided on the surface of the liquid chamber cover member H 121 which faces the part slide piece K 221 in order to increase the holding force. However, when the holding force is too strong, it is difficult to perform demolding after secondary molding. As a result, there is the risk of a finished product being damaged. For this reason, the inside of the sleeve structure (convex portion) H 122 has a concave and conic shape H 123 ( FIG. 4B ) in which a peripheral surface forms a taper H 124 ( FIG. 4B ) in order to obtain strong front and rear holding forces and a high demolding performance. A mold structure forming the taper H 124 is an insert pin structure such that a material of which the holding force is to be arbitrarily adjusted according to the material used and the structure of surrounding products can be arbitrarily changed.

In the next process illustrated in FIG. 7C , with the part slide piece K 221 evacuated, the die slide K 230 provided in the movable mold K 200 is moved in the direction of an arrow A 3 in FIG. 7C (die sliding is relatively performed). In this case, the molded liquid supply member H 100 that is held by the die slide K 230 is moved in the direction of the arrow A 3 to a position where it can come into contact with the liquid chamber cover member H 121 . Similarly to the part slide mechanism, the die slide K 230 is driven by a driving mechanism different from the mold opening and closing mechanism.

Then, in the process illustrated in FIG. 8A , the molded liquid chamber cover member H 121 held by the part slide piece K 221 is moved to the third molding position K 225 in the direction of an arrows A 4 in FIG. 8A by a return operation of the part slide mechanism so as to come into contact with the opening portion of the liquid chamber H 110 in the liquid supply member H 100 . The valve gates K 130 and K 131 for injecting a material are also provided at the third molding position K 225 .

Here, the valve gates provided in the mold according to this embodiment have the same structure and have the cross-sectional size represented by a dashed line in the drawings. Therefore, when the valve gates are arranged so as to be adjacent to each other, they need to be arranged at a pitch that is equal to or greater than the diameter of the circle. The valve gate for molding the liquid chamber cover member H 121 and the valve gates K 130 and K 131 provided at the third molding position are arranged so as not to be adjacent to each other since they need to be arranged at a pitch that is equal to or greater than the diameter of the circle in the cross-sectional view of the valve gates. Therefore, in this embodiment, the molding position of the liquid chamber cover member H 121 is different from the third molding position K 225 . That is, the part slide mechanism has three stop positions, that is, the second molding position K 220 where the liquid chamber cover member H 121 is molded, an evacuation position for avoiding the die slide, and the position where the liquid supply member H 100 is contacted and joined with the liquid chamber cover member H 121 .

Then, the mold is clamped with the liquid chamber cover member H 121 coming into contact with the opening portion of the liquid chamber H 110 in the liquid supply member H 100 at the third molding position K 225 .

Then, in the process illustrated in FIG. 8B , the contact portion between the liquid chamber cover member H 121 and the opening portion of the liquid chamber H 110 in the liquid supply member H 100 is filled with a material which is compatible with the liquid supply member H 100 and the liquid chamber cover member H 121 , without any space therebetween, such that the liquid supply member H 100 and the liquid chamber cover member H 121 are hermetically joined with each other. The sealing material includes filler. In the liquid chamber H 110 , a hollow portion with a sealed structure is formed by filling with the material except for the opening which is connected to the sub-tank H 030 and is on the side of the filter H 101 and the opening on the side of the printing element unit H 020 .

Finally, in the process illustrated in FIG. 8C , the mold K 001 is opened and the part slide piece K 221 is moved in the direction of an arrow A 5 in FIG. 8C . In addition, the liquid supply member H 100 in which the sealed hollow structure has been completed is pushed out and is taken out of the mold K 001 .

The use of the mold K 001 having the structure that performs the above-mentioned operation makes it possible to suppress an increase in the opening and closing stroke of the stationary mold K 100 and the movable mold K 200 . As a result, it is possible to prevent an increase in the sizes of a mold and a molding machine and thus to manufacture an inkjet print head with a small size at a low cost.

In this embodiment, when a contact portion between two components is located at a deep position in one of the components as compared to the case illustrated in FIG. 9A , the arrangement position of a valve gate for injecting a molding material for sealing the contact portion between the two components is far away from the contact position between the two components. As illustrated in FIG. 9B , a cylindrical gate runner H 631 is provided from an outermost portion of a product after the two components are contacted and joined with each other to a contact portion H 625 between the two components and a molding material is introduced from the gate valve K 150 . This gate runner structure makes it possible to improve flexibility in the position of the contact portion between the two components and flexibility in the structure of a mold and layout, that is, to prevent an increase in the size of a mold and the size of a molding machine.

FIGS. 10A and 10B are diagrams illustrating an inkjet print head H 001 into which a sub-tank H 130 having a function of connecting a supply tube (not illustrated) that supplies a liquid, such as ink, is incorporated, with a liquid supply member H 100 and a liquid chamber cover member H 121 joined with each other. As such, when the mold structure according to the invention is applied, it is possible to complete components in the same mold through a series of operations even if the number of components increases.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No. 2015-105091 filed May 25, 2015, which is hereby incorporated by reference wherein in its entirety.