Printing apparatus

The present invention relates to a printing apparatus.

A method for supplying ink from an ink containing portion to a printhead through a flexible tube is known as an ink supply method that can be employed in an ink jet printing apparatus (for example, Japanese Patent Laid-Open No. 2006-159603). Such an ink supply method is mainly employed in relatively large printing apparatuses that print images on a large printing medium.

Since a printhead is mounted on a carriage and reciprocates, a channel that extends in a reciprocation direction of the carriage, and a channel that is diverted from the aforementioned channel toward the ink containing portion, are required as ink supply channels. A tube that causes a small pressure drop and has high gas barrier properties is advantageous as a tube that forms an ink channel. However, generally, such a tube tends to have a large diameter and be hard. Therefore, when a hard tube with a large diameter is employed in the area where a channel is to be diverted as described above, the tube needs to be bent along a large curve, which leads to an increase in the size of the apparatus because a large space needs to be secured.

The present invention provides technology for downsizing an apparatus with forming an ink channel.

According to an aspect of the present invention, there is provide a printing apparatus comprising: a printhead configured to perform printing by discharging ink onto a printing medium; a carriage, on which the printhead is mounted, configured to reciprocate; a first containing unit configured to contain ink to be supplied to the printhead; and a channel forming unit configured to form an ink supply channel for supplying ink to the printhead, wherein the channel forming unit includes: a first tube which extends in a reciprocation direction of the carriage; a second tube which is connected to the first containing unit; and a first coupling member which couples the first tube and the second tube to each other, and wherein the first coupling member is located in one end portion of the printing apparatus in the reciprocation direction, and includes a bent channel which communicates the first tube and the second tube to each other.

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

FIG. 1 is an external view of a printing apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an internal structure of the printing apparatus in FIG. 1 .

FIG. 3 is a perspective view showing a structure of an ink supply system of the printing apparatus in FIG. 1 .

FIG. 4 is an exploded perspective view of the structure of the ink supply system shown in FIG. 3 .

FIG. 5 is a perspective view of an ink supply unit.

FIG. 6 is a perspective view showing a structure around a carriage.

FIG. 7 is a diagram illustrating a coupling member.

FIG. 8 is a diagram showing a situation where a right outer cover of the printing apparatus in FIG. 1 has been removed.

FIG. 9 is a diagram illustrating a restriction structure that restricts a right coupling member from being displaced.

FIG. 10 is a diagram illustrating a restriction structure that restricts a left coupling member from being displaced.

FIG. 11 is a diagram illustrating the restriction structure that restricts the left coupling member from being displaced.

FIG. 12 is a diagram illustrating the arrangement of the left and right coupling members.

FIG. 13 is a diagram illustrating the arrangement of the right coupling member.

Following describes a printing apparatus according to embodiments of the present invention with reference to the drawings. In the drawings, arrows X, Y, and Z respectively indicate a front-rear direction (a depth direction), a left-right direction (a width direction, which is the lengthwise direction of the apparatus), and a top-bottom direction in a front view of the printing apparatus. Also, “F” indicates the front side, “B” indicates the rear side, “L” indicates the left side, and “R” indicates the right side.

Note that “print” includes not only formation of significant information such as a character or graphic pattern but also formation of an image, design, or pattern on print media in a broader sense or processing of print media regardless of whether the information is significant or insignificant or has become obvious to allow human visual perception. In this embodiment, “printing media” are assumed to be paper sheets but may be fabrics, plastic films, and the like.

Overview of Printing Apparatus

FIG. 1 is an external view of a printing apparatus 1 according to the present embodiment. FIG. 2 is a perspective view showing the internal structure of the printing apparatus 1 , and shows a situation where a cover member 10 has been removed from FIG. 1 . The cover member 10 forms an outer casing of the printing apparatus 1 , and encloses the internal structure.

The printing apparatus 1 is a serial ink jet printing apparatus, and includes a printhead 2 , a carriage 3 , ink supply units 4 A and 4 B, a feeding mechanism 5 , a conveyance mechanism 6 , and a recovery mechanism 9 . The printing apparatus 1 has a right end portion 1 a and left end portion 1 b , which are one end portion and the other end portion in the Y direction.

The feeding mechanism 5 and the conveyance mechanism 6 are mechanisms for conveying a printing medium. In the present embodiment, a printing medium is conveyed in the X direction. The feeding mechanism 5 includes a sheet attachment portion 5 a . A printing medium that is wound into a roll (a roll sheet) can be attached to the sheet attachment portion 5 a . The printing apparatus 1 is an apparatus that can print images onto a printing medium that has a large size such as the A0 size or the B0 size.

The feeding mechanism 5 includes, for example, a feeding roller that conveys a printing medium, and a guide that forms a conveyance path of a printing medium and guides the printing medium moving. In the present embodiment, the feeding mechanism 5 first conveys the printing medium, which is attached to the sheet attachment portion 5 a , rearward in the X direction, thereafter bends the printing medium upward, and then conveys the printing medium forward in the X-direction.

The conveyance mechanism 6 includes, for example, a feeding roller that conveys a printing medium, and a guide that forms a conveyance path of a printing medium and guides the printing medium moving. The conveyance mechanism 6 conveys a printing medium that has been fed by the feeding mechanism 5 , and discharges the printing medium from a discharging portion 1 c . The printhead 2 prints images onto a printing medium while the conveyance mechanism 6 conveys the printing medium.

The printhead 2 has a plurality of orifices from which ink is discharged, and prints an image by discharging ink onto a printing medium that is conveyed by the conveyance mechanism 6 . The printhead 2 is mounted on the carriage 3 .

The carriage 3 is configured to reciprocate in the Y direction by being guided by a plurality of guide shafts 11 that extend along the Y direction. A driving mechanism for moving the carriage 3 includes a motor and a belt transmission mechanism, for example. The belt transmission mechanism includes a driving pulley, a driven pulley, and a belt wound around these pulleys. The carriage 3 is fixed to a portion of the belt, and moves due to the belt running.

The recovery mechanism 9 is located on the right end portion 1 a of the printing apparatus 1 . The recovery mechanism 9 is a mechanism for maintain and recover ink discharge performance of the printhead 2 . The recovery mechanism 9 includes a cap and a wiper, for example. Operations to maintain and recover the ink discharge performance of the printhead 2 include a preliminary discharge operation and a cleaning operation, for example. The preliminary discharge operation is an operation to discharge ink from the printhead 2 . The cleaning operation is an operation to cap the printhead 2 using the cap, to suck ink from the printhead 2 under negative pressure, or to wipe the ink discharge surface of the printhead 2 using the wiper.

The ink supply units 4 A and 4 B are sources of ink that is discharged by the printhead 2 . The ink supply units 4 A and 4 B each include six attachment portions to which ink tanks 4 a are respectively attached. Therefore, twelve types of ink are available at the maximum. In the example shown in the drawing, ink tanks 4 a are respectively attached to four attachment portions in the six attachment portions.

In the present embodiment, the ink supply units 4 A and 4 B are located at the rear side of the printing apparatus 1 rather than the carriage 3 . This location makes it possible to reduce a width w of the printing apparatus 1 and downsize the apparatus compared to when the ink supply units 4 A and 4 B are located sideward of the carriage 3 in the Y direction. The ink supply unit 4 A is located in a rear portion of the right end portion 1 a of the printing apparatus 1 , and the ink supply unit 4 B is located in a rear portion of the left end portion 1 b of the printing apparatus 1 . It is possible to form the ink supply channels to the printhead 2 in a balanced manner by symmetrically arranging the ink supply units 4 A and 4 B in the Y direction.

When printing onto a printing medium is performed using the above-described configuration, the printing medium is conveyed to a predetermined printing start position by the conveyance mechanism 6 . Thereafter, an operation to discharge ink while moving the printhead 2 in the Y direction using the carriage 3 and an operation to move the printing medium forward in the X direction using the conveyance mechanism 6 are repeated, and thus printing onto the entire printing medium is performed.

Ink Supply System

The following describes an ink supply system for supplying ink from the ink supply units 4 A and 4 B to the printhead 2 with reference to FIGS. 2 and 3 to 6 . FIG. 3 is a perspective view showing a structure of an ink supply system of the printing apparatus 1 , FIG. 4 is an exploded perspective view of the structure shown in FIG. 3 , and FIG. 5 is a perspective view of the ink supply unit 4 A. FIG. 6 is a perspective view showing a structure around the carriage 3 .

The printing apparatus 1 includes a channel forming unit 7 that forms ink supply channels for supplying ink from the ink supply units 4 A and 4 B to the printhead 2 .

The channel forming unit 7 includes tubes 71 R to 74 R and a coupling member 75 R that form channels from the ink supply unit 4 A to the printhead 2 , and tubes 71 L to 74 L and a coupling member 75 L that form channels from the ink supply unit 4 B to the printhead 2 . The channel forming unit 7 also includes a coupling member 70 that is shared between these two channel systems.

Ink is supplied from the ink supply unit 4 A to the printhead 2 through the plurality of tubes 72 R, the coupling member 75 R, the plurality of tubes 71 R, the coupling member 70 , the plurality of tubes 73 R, the carriage 3 , the plurality of tubes 74 R, and the printhead 2 , in this order. The number of tubes 71 R to 74 R is greater than or equal to the number of types of ink in the ink supply unit 4 A. Ink is supplied from the ink supply unit 4 B to the printhead 2 through the plurality of tubes 72 L, the coupling member 75 L, the plurality of tubes 71 L, the coupling member 70 , the plurality of tubes 73 L, the carriage 3 , the plurality of tubes 74 L, and the printhead 2 , in this order. The number of tubes 71 L to 74 L is greater than or equal to the number of types of ink in the ink supply unit 4 B.

The tubes 71 R and 71 L extend straight in the Y direction. The printing apparatus 1 include a frame 12 that supports the tubes 71 R and 71 L. In the present embodiment, the frame 12 is a plate member that extends in the Y direction in a belt-like shape, and is made of metal, for example. The tubes 71 R and 71 L are placed on the upper surface of the frame 12 .

Restriction members 12 a that restrict the tubes 71 R and 71 L from being displaced in a direction that intersects the Y direction are respectively fixed to a plurality of positions of the frame 12 . The restriction members 12 a are members that each have an inverted U shape (or a gate shape), and gaps that allow the tubes 71 R or 71 L to pass through are formed between the frame 12 and the restriction members 12 a . The restriction members 12 a restrict the tubes 71 R or 71 L from being lifted, and from being displaced in the X direction. It is possible to prevent the tubes 71 R and 71 L from interfering with components around the tubes 71 R and 71 L by restricting the tubes 71 R and 71 L from being displaced. The tubes 71 R and 71 L may expand and contract depending on the thermal environment in which the tubes 71 R and 71 L are used. Therefore, the restriction members 12 a do not restrict the tubes 71 R and 71 L from being displaced in the Y direction.

The coupling member 70 is located in a central portion of the printing apparatus 1 in the Y direction. The ends of the tubes 71 R and 71 L on the central portion side are connected to the coupling member 70 . The tubes 71 R extend from the coupling member 70 to the end portion 1 a of the printing apparatus 1 , and the ends of the tubes 71 R are connected to the coupling member 75 R. The tubes 71 L extend from the coupling member 70 to the end portion 1 b of the printing apparatus 1 , and the ends of the tubes 71 L are connected to the coupling member 75 L.

The tubes 72 R connect the tubes 71 R and the ink supply unit 4 A to each other, and the tubes 72 L connect the tubes 71 L and the ink supply unit 4 B to each other. The ends of the tubes 72 R on one side are connected to the coupling member 75 R. The tubes 72 R extend from the coupling member 75 R in a direction that intersects the direction in which the tubes 71 R extend (in the present embodiment, rearward in the X direction), runs to the rear side of the ink supply unit 4 A, and is connected to the ink supply unit 4 A. The ends of the tubes 72 L on one side are connected to the coupling member 75 L. The tubes 72 L extend from the coupling member 75 L in a direction that intersects the direction in which the tubes 71 L extend (in the present embodiment, rearward in the X direction), runs to the rear side of the ink supply unit 4 B, and is connected to the ink supply unit 4 B.

As shown in FIG. 5 , ink containing portions 4 b that are configured to contain ink from the ink tanks 4 a are provided in a lower portion of the ink supply unit 4 A. The ink containing portions 4 b are ink containing spaces that are formed respectively corresponding to the ink tanks 4 a (the attachment portions). The ink containing portions 4 b may be storages that are configured to store a predetermined amount of ink, or substantially only relay channels between the ink tanks 4 a and the tubes 72 R. The rear ends of the tubes 72 R are connected to the ink containing portions 4 b , on the back side of the ink supply unit 4 A. The tubes 72 L and the ink supply unit 4 B have the same configurations as described above.

The tubes 73 R connect the tubes 71 R and the carriage 3 to each other, and the tubes 73 L connect the tubes 71 L and the carriage 3 to each other. Connection members 73 a and 73 b for connecting channels are provided at ends of the tubes 73 R and 73 L. The connection members 73 a are connected to the carriage 3 , and the connection members 73 b are connected to the coupling member 70 .

The tubes 73 R and 73 L are bent and protrude in the Y direction in a U shape, and deform according to the back and forth movement of the carriage 3 while changing the bending positions. The printing apparatus 1 includes tube holding members 8 R and 8 L to guide the tubes 73 R and 73 L deforming according to the back and forth movement of the carriage 3 .

In the present embodiment, the tube holding members 8 R and 8 L are chain links (cable carriers) that each include a plurality of link members 80 that are coupled to each other. The link members 80 each have a ring-like shape that allows tubes to be inserted thereinto, and adjacent link members 80 are coupled to each other so as to be rotatable relative to each other about an axis that extends in the X direction. The tube holding members 8 R and 8 L are bent and protrude in the Y direction in a U shape, and deform according to the back and forth movement of the carriage 3 while changing the bending positions. The tubes 73 R are inserted into the tube holding member 8 R, and the tubes 73 L are inserted into the tube holding member 8 L. The tube holding members 8 R and 8 L prevent the tubes 73 R and 73 L from swelling, and guide the tubes 73 R and 73 L deforming. The carriage 3 is provided with a guide portion 31 in a main body 30 on which the printhead 2 is mounted. The guide portion 31 prevents the tube holding members 8 R and 8 L from being lifted.

The tubes 74 R connect the carriage 3 and the printhead 2 to each other, and the tubes 74 L connect the carriage 3 and the printhead 2 to each other. In the present embodiment, the tubes 73 R and the tubes 74 R are connected to each other through the carriage 3 . The carriage 3 includes portions that are connected to these tubes, and channels. The same applies to the tubes 73 L and the tubes 73 R.

All of the tubes 71 R to 74 R and 71 L to 74 L are flexible resin tubes. All of the tubes may be the same or different. Generally, a tube that causes a small pressure drop and has high gas barrier properties is advantageous as a tube that forms an ink channel. However, generally, such a tube tends to have a large diameter, to be hard, and to be expensive. Therefore, a different type of tube may be used depending on the position.

For example, the tubes 71 R and 71 L extend straight, and do not move when the carriage 3 moves. Therefore, it is possible to use tubes that are thick (have a large channel diameter) and hard (have high gas barrier properties). The tubes 73 R and 73 L are repeatedly bent according to the movement of the carriage 3 . Therefore, highly flexible tubes are advantageous. The tubes 72 R, 72 L, 74 R, and 74 L need to be statically bent, but need not to be dynamically bent. Therefore, a certain degree of flexibility suffices. From the above-described point of view, the tubes may have, for example, the following relationship in terms of thickness: the tubes 71 R (thick)>the tubes 72 R and 74 R≥the tubes 73 R (thin), or the tubes 71 R (thick)>the tubes 72 R and 74 R>the tubes 73 R (thin). Also, the following relationship in terms of the gas barrier properties (hardness) may be satisfied: the tubes 71 R (hard)>the tubes 72 R and 74 R≥the tubes 73 R (soft), or the tubes 71 R (hard)>the tubes 72 R and 74 R>the tubes 73 R (soft). The same applies to the tubes 71 L to 74 L. Alternatively, the tubes 71 R and the tubes 71 L, the tubes 72 R and the tubes 72 L, the tubes 73 R and the tubes 73 L, the tubes 74 R and the tubes 74 L respectively have the same thickness and hardness.

The coupling members 70 , 75 R, and 75 L are relay members that connect tubes. These coupling members can be formed using block-shaped hard synthetic resins in which ink channels are formed, for example. In the present embodiment, the coupling member 70 is fixed to the frame 12 , whereas the coupling members 75 R and 75 L are not fixed and are placed on the frame 12 .

The following describes the configuration of the coupling member 75 L with reference to FIG. 7 . FIG. 7 illustrates the coupling member 75 L, and shows a disassemble state and an assembled state. The coupling member 75 R have the same configuration as the coupling member 75 L (reversed in the left-right direction).

The coupling member 75 L includes a main member 76 , a cover sheet 77 , a connection member 78 , and an elastic member 79 . The main member 76 is a member in which a plurality of grooves 76 c that serve as internal channels are formed, and is formed using a hard synthetic resin (e.g. a polypropylene resin). The main member 76 includes a plurality of cylindrical connection portions 76 a to which the tubes 72 L are connected, and a plurality of cylindrical connection portions 76 b on the tubes 71 L side. The axial direction of the connection portions 76 a is the X direction, and the direction in which the connection portions 76 a and the tubes 72 L are connected is the X direction. The grooves 76 c are formed such that connection portions 76 a and the connection portions 76 b communicate with each other, and are open in the upper surface of the main member 76 .

The cover sheet 77 is a film that closes the openings of the grooves 76 c , and is, for example, a thin film that is made of a synthetic resin on which aluminum has been deposited using vapor deposition, and is welded to the upper surface of the main member 76 . To form the internal channels, it is possible to form closed holes in the main member 76 instead of the grooves 76 c . However, it is possible to more easily manufacture the main member 76 by combining the grooves 76 c with the cover sheet 77 as in the present embodiment.

In the present embodiment, the axial direction of the connection portions 76 a and the axial direction of the connection portions 76 b are orthogonal to each other, and the external shape of each of the grooves 76 c is the shape of a 90 degree arc that curves from one end to the other end. In the present embodiment, channels that are bent by 90 degrees are formed by the grooves 76 c and the cover sheet 77 . The degree of curvature of the channels can be determined according to the angle of intersection of the tubes 71 L and the tubes 72 L. If a sharp curve is required, the degree of curvature of the channels may be selected from the range of 70 degrees to 110 degrees, or the range of 80 degrees to 100 degrees, for example.

A configuration in which the tubes 71 L are directly connected to the connection portions 76 b may be employed. However, in the present embodiment, the elastic member 79 and the connection member 78 are intervened therebetween. This configuration makes it easier to separate the tubes 71 L and the tubes 72 L from each other at the time of maintenance.

The connection member 78 includes a plurality of cylindrical connection portions 78 b to which the tubes 71 L are connected, and is formed using a hard synthetic resin (e.g. a polyacetal resin). The axial direction of the connection portions 78 b is the Y direction, and the direction in which the connection portions 78 b and the tubes 71 L are connected is the Y direction. The connection member 78 includes engagement portions 78 a that engage with engagement portions 76 d of the main member 76 . The engagement portions 76 d are claw-shaped protruding pieces, and the engagement portions 78 a are openings into which the engagement portions 76 d are inserted. The engagement portions 78 a are slits that extend in the Y direction, and the connection member 78 are engaged with the main member 76 so as to be displaceable in the Y direction.

The elastic member 79 is a rubber member that includes cylindrical connection portions that respectively connect the connection portions 78 b and the connection portions 76 b to each other. Due to the elastic member 79 being intervened between the connection member 78 and the main member 76 , the connection member 78 and the main member 76 are biased by the elastic member 79 in directions away from each other. Thus, the connection member 78 and the main member 76 are locked to each other. The elastic member 79 also secure the sealing properties of the channels.

Next, displacement restriction structures for the coupling members 75 R and 75 L will be described. The coupling members 75 R and 75 L are basically placed on the frame 12 without being fixed, and are configured to be displaceable in the Y direction according to thermal contraction of the tubes 71 R and 71 L. However, if the coupling members 75 R and 75 L are unnecessary displaced, the tubes may become detached or interfere with components around the tubes. Therefore, in the present embodiment, the coupling members 75 R and 75 L are configured to be displaceable in the Y direction and restricted from being displaced in the X direction that intersects the Y direction.

The following describes the displacement restriction structure for the coupling member 75 R with reference to FIGS. 8 and 9 . FIG. 8 is a perspective view showing a situation where a cover member 10 a has been removed, and FIG. 9 is a perspective view showing a structure around the coupling member 75 R.

Note that the cover member 10 a is a portion of the cover member 10 , and forms an outer casing for a right portion of the printing apparatus 1 . In the present embodiment, the coupling member 75 R is located at the rightmost end of the internal structure of the printing apparatus 1 . The coupling member 75 R is located so as to face the inner surface of the cover member 10 a , and so as to be exposed when the cover member 10 a is removed. Thus, a configuration that makes it easier to access the coupling member 75 R at the time of maintenance is employed.

Also, as with the coupling member 75 L described with reference to FIG. 7 , the coupling member 75 R is also configured such that the main member 76 thereof can be separated from the connection member 78 in the Y direction. Therefore, at the time of maintenance, it is possible to separate the tubes 71 R and the tubes 72 R from each other by separating the main member 76 of the coupling member 75 R from the connection member 78 to, for example, replace the tubes 72 R. Note that a left portion of the printing apparatus 1 has the same configuration, and the coupling member 75 L is exposed when the cover member for the left portion is removed.

A component part 13 that forms the recovery mechanism 9 is located forward of the coupling member 75 R in the X direction. The component part 13 has a rear surface that faces the front surface of the coupling member 75 R, and restricts the coupling member 75 R from being displaced forward. That is, the component part 13 also serves as a restriction member that restricts the coupling member 75 R from being displaced forward. In this way, by using the component part 13 , which has another purpose, as the restriction member, it is possible to restrict the coupling member 75 R from being displaced, without increasing the number of parts. Note that the coupling member 75 R is not restricted from being displaced rearward because the tubes 72 R are located rearward of the coupling member 75 R.

The following describes the displacement restriction structure for the coupling member 75 L with reference to FIGS. 10 and 11 . FIG. 10 illustrates a mode of separation of the coupling member 75 L is separated, and FIG. 11 is a perspective view showing the displacement restriction structure for the coupling member 75 L.

The frame 12 has a rectangular cutout 12 b at the left end thereof. A rib 76 e is provided on the bottom surface of the main member 76 of the coupling member 75 L. Note that the coupling member 75 R does not have the rib 76 e . The rib 76 e is inserted into the cutout 12 b , and the peripheral edge of the cutout 12 b and the rib 76 e interfere with each other. Thus, the coupling member 75 L is restricted from being displaced in the X direction (particularly in the forward direction).

Next, the positions of the coupling members 75 R and 75 L will be described with reference to FIGS. 12 and 13 . FIG. 12 schematically shows the positions of the coupling members 75 R and 75 L, and FIG. 13 shows the position of the coupling member 75 R.

The coupling member 75 R is located in the right end portion 1 a (see FIG. 1 ) of the printing apparatus 1 , and the coupling member 75 L is located in the left end portion 1 b (see FIG. 1 ) of the printing apparatus 1 . Both the coupling member 75 R and the coupling member 75 L are located outside a width WP of the conveyance system of the printing apparatus 1 (the maximum width of available printing media) in the Y direction. Note that the coupling member 75 R may be located within the range of ⅛, 1/16, or 1/32 the apparatus's width W, from the right end of the printing apparatus 1 , for example. Similarly, the coupling member 75 L may be located within the range of ⅛, 1/16, or 1/32 the apparatus's width W, from the left end of the printing apparatus 1 , for example.

The coupling members 75 R and 75 L allow the tubes to change their orientation by a sharp angle at the positions where the coupling members 75 R and the 75 L are located, which makes it possible to downsize the printing apparatus 1 in the Y direction.

Specifically, in the present embodiment, the tubes 71 R extend in the Y direction, whereas the tubes 72 R extend from the tubes 71 R in a direction that is substantially orthogonal to the tubes 71 R. If the coupling member 75 R is not intervened and the tubes 71 R and the tubes 72 R are replaced with tubes 71 R′, the tubes 71 R′ need to be looped so as to protrude outward in the Y direction as indicated by dotted lines in FIG. 12 . If thick and hard tubes are used as the tubes 71 R′, the amount of this loop will be large. Similarly, if the coupling member 75 L is not intervened and the tubes 71 L and the tubes 72 L are replaced with tubes 71 L′, the tubes 71 L′ need to be looped so as to protrude outward in the Y direction as indicated by dotted lines in FIG. 12 .

When the coupling members 75 R and 75 L are used, the width of the apparatus excluding the outer casing is the width W 1 . On the other hand, when the coupling members 75 R and 75 L are not used, the width of the apparatus is the width W 2 (>W 1 ). In this way, using the coupling members 75 R an 75 L makes it possible to employ thick hard tubes, and to downsize the printing apparatus 1 .

Next, in FIG. 12 , a range R 1 indicates the range of movement of the carriage 3 , and a range R 2 indicates the range of movement of the tube holding members 8 R and 8 L. In the present embodiment, the positions of the coupling members 75 R and 75 L in the Y direction overlap the range R 1 and the range R 2 . FIG. 13 more specifically shows the position of the coupling member 75 R. In the example shown in the drawing, the carriage 3 is located at the right end of the range R 1 . The tube holding member 8 R is also located at the right end of the range R 2 . The position of the right end of the guide portion 31 of the carriage 3 is the position of the rightmost end of the carriage 3 . It can be understood that a portion of the coupling member 75 R and the guide portion 31 overlap each other when viewed in the Z direction. That is, the position (Y 1 ) of the coupling member 75 R in the Y direction overlaps the range R 1 . Also, the position of the right end of the curve of the tube holding member 8 R is the position of the rightmost end of the tube holding member 8 R. It can be understood that a portion of the coupling member 75 R and the tube holding member 8 R overlap each other when viewed in the Z direction. That is, the position (Y 1 ) of the coupling member 75 R in the Y direction overlaps the range R 2 . The same applies to the positional relationship between the coupling member 75 L and the ranges R 1 and R 2 .

With such a configuration, in the present embodiment, it is possible to approximate the range of movement R 1 of the carriage 3 and the range of movement R 2 of the tube holding members 8 R and 8 L to the width W of the printing apparatus 1 . The range of movement of the carriage 3 or the like within the apparatus's width corresponds to the width of an available printing medium, and cannot be reduced. However, this range of movement approximates to the apparatus's width, and this means that there is no wasted space in the width direction of the printing apparatus 1 . That is, it is possible to provide a user with the printing apparatus 1 that is downsized in the width direction.

Other Embodiments

In the above-described embodiment, the ink supply units 4 A and 4 B are located rearward of the carriage 3 . However, such a configuration is not essential, and the ink supply units 4 A and 4 B may be located downward or forward of the carriage 3 . Although the tubes 72 R and 72 L extend rearward from the corresponding coupling members 75 R and 75 L, the tubes 72 R and 72 L may extend downward or forward depending on the positions of the ink supply units 4 A and 4 B.

The method employed to supply ink from the ink supply units 4 A and 4 B to the printhead 2 may be a method utilizing a difference between hydraulic heads, or another method (e.g. a pressurizing method).

In the above-described embodiment, chain links are used as the tube holding members 8 R and 8 L. However, other holding members (e.g. resin sheets or leaf springs) may be used. Also, it is possible to employ a configuration in which no tube holding member is used.

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 benefits of Japanese Patent Application No. 2017-114552, filed Jun. 9, 2017, which is hereby incorporated by reference herein in its entirety.