Recording apparatus

An apparatus includes a gap adjuster that adjusts a gap in a vertical direction between a recording head and a supporting surface for supporting a medium. The gap adjuster adjusts the gap by engagement of a carriage, a slide member, and a cam member that is provided therebetween and has a stepped portion with an alternate-arrangement structure in a width direction. The gap adjuster includes a coil spring that urges the carriage with respect to the slide member in the direction that is the opposite of the transportation direction. A slide contact member is provided on an end of the coil spring.

The present application is based on, and claims priority from JP Application Serial Number 2020-070870, filed Apr. 10, 2020, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

Embodiments of the present disclosure relate to a recording apparatus.

2. Related Art

In related art, a recording apparatus that includes a mechanism for adjusting in multiple steps a gap between a recording head and a supporting surface for supporting a medium is known. For example, a gap adjuster of a recording apparatus disclosed in JP-A-2014-14938 includes a slide member configured to move in a width direction together with a carriage and includes a cam member configured to cause the carriage to move in a vertical direction, and switches a gap in multiple steps by means of the slide member and the cam member.

The recording apparatus disclosed in JP-A-2014-14938 includes coil springs that urge the carriage with respect to the slide member in a predetermined direction. Slide operation of the end surface of the coil spring and the carriage is performed when the gap is switched. However, in related art, there is a possibility that print quality might decrease because a desired gap cannot be obtained due to obstruction of the slide operation of the end surface of the coil spring by the spring end.

SUMMARY

A recording apparatus according to a certain aspect of the present disclosure includes: a recording head that performs recording on a medium that is transported; a carriage on which the recording head is mounted and which is configured to move in a width direction intersecting with a transportation direction of the medium; a guide member that extends in the width direction and guides the carriage in the width direction; and a gap adjuster that causes the carriage to change in position in a first direction in which a gap between the recording head and a supporting surface for supporting the medium at a position facing the recording head changes, the gap adjuster including a slide member that moves in the width direction together with the carriage while sliding on the guide member; a cam member provided between the carriage and the slide member and having a stepped portion in which keeping surfaces for keeping the position of the carriage in the first direction and adjustment surfaces for changing the position of the carriage in the first direction are arranged alternately in the width direction; and a first urging member that urges the carriage with respect to the slide member in a direction that is opposite of the transportation direction; wherein the first urging member is equipped with a slide contact member that slides on the carriage.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

First, the outline of a recording apparatus according to an exemplary embodiment of the present disclosure will now be described. In the present embodiment, a serial-type ink-jet multifunction printer1is taken as an example of a recording apparatus. In the X-Y-Z coordinate system illustrated in each drawing, the X direction represents a width direction or a scan direction, the Y direction represents a depth direction or a direction parallel to a sheet-transportation direction, and the Z direction represents a height direction or a vertical direction or a first direction. The direction indicated by the head of the Y-directional arrow will be referred to as “frontward” or “downstream”. The direction indicated by the tail of the Y-directional arrow will be referred to as “rearward” or “upstream”. As viewed from the front of the apparatus, “left” is defined as the side indicated by the head of the X-directional arrow, and “right” is defined as the side indicated by the tail of the X-directional arrow. The direction indicated by the head of the Z-directional arrow will be referred to as “vertically upward”, and the direction indicated by the tail of the Z-directional arrow will be referred to as “vertically downward” or the direction of gravity. The sheet-transportation direction is the direction from the tail toward the head of the Y-directional arrow.

The ink-jet multifunction printer1illustrated inFIG. 1includes a printer unit3and a scanner unit4. The printer unit3includes a recording unit8housed inside a box-shaped housing2and configured to perform recording on a medium P. The scanner unit4is mounted over the printer unit3and reads a document image.

The scanner unit4is provided over the printer unit3rotatably. As illustrated inFIG. 2, the scanner unit4has a pivot shaft4aat the rear of the housing2along the X direction and is able to pivot such that the front of the housing2turns as a free end4b. By rotating, the scanner unit4fulfills a function of an openable-and-closable cover for opening the top of the printer unit3.

As illustrated inFIG. 3, the scanner unit4includes a scanner mainframe40, which is equipped with a non-illustrated reader inside, and a document table cover42, which can be opened and closed for a document table41provided at the top of the scanner mainframe40. The document table cover42can be opened and closed alone. The document table41becomes exposed when the document table cover42is opened. The reader reads a document placed on the document table41. The document is placed on the document table41, with its reading target surface facing the document table41.

An operation unit6for operating the scanner unit4is provided at the front of the apparatus. The operation unit6has a liquid crystal touch panel display function. The operation unit6can be used for performing various setting operations and execution operations for recording and image reading. In addition, the operation unit6is able to perform setting content display and image preview display, etc. Although the operation unit6is provided on the scanner unit4, the operation unit6can be used also for, for example, paper type setting and ink replacement, which are functions of the printer unit3.

The printer unit3includes the recording unit8, a medium feeding unit32, and a transportation unit33. The recording unit8includes a recording head10, which performs recording by ejecting ink toward the medium P that is transported, and a carriage20, on which the recording head10is mounted and which reciprocates in the width direction intersecting with the transportation direction of the medium P. The medium feeding unit32includes a lower tray30, which is able to accommodate a plurality of sheets of the medium P, and an upper tray31. The transportation unit33transports the medium P fed from the medium feeding unit32to the recording unit8and ejects the medium P.

The printer unit3is configured to be refillable for replenishment of ink whose amount has decreased due to recording. As illustrated inFIG. 1, the printer unit3according to the present embodiment has a liquid container unit24provided at the front inside the housing2. Refilling of the liquid container unit24with ink is performed with the scanner unit4opened. A cap5for closing an ink supply opening is provided on the top of each of the liquid containers24. After opening the cap5, a user is able to pour ink into the liquid container24from a separate ink bottle. Slits are provided at a part of the front2aof the housing2. Each of the liquid containers24has a window3athat makes it possible to visually confirm the amount of ink contained in the liquid container24through the slit. The user is able to refill the liquid container24with ink properly while visually checking the amount of ink contained in the liquid container24.

As illustrated inFIG. 4, ink supply tubes25are provided along the width direction at a space in front of the carriage20and behind the liquid container unit24. For each color, one end of the ink supply tube25is connected to the liquid container24. The ink supply tubes25are arranged to extend in the X direction toward the opposite side in the width direction in relation to the position where the liquid container unit24is provided. The ink supply tubes25are fastened by being bound with binding bands together with the frame of the apparatus in a binding direction intersecting with the ink supply tubes25up to a halfway point in the scan width of the carriage20. The ink supply tubes25bound with binding bands are bent back gently upward from the halfway-point one of the binding bands in such a way as to form a U-like curve and then extend approximately up to a position for connection to the liquid containers24. The other end of each of the ink supply tubes25is inserted through the front of the housing of the carriage20to be connected to the recording head10of the corresponding color. A thin FPC restriction member27is provided on the ink supply tubes25bent upward in the U shape. The FPC restriction member27binds the ink supply tubes25in a binding direction intersecting with the ink supply tubes25and extends vertically down at the front side of the ink supply tubes25. The FPC restriction member27is provided almost at a halfway point in the scan width of the carriage20. However, the FPC restriction member27may be provided at any other arbitrary position in the X direction, or at a plurality of positions, on the ink supply tubes25bent upward in the U shape.

Flexible printed boards26, each for communicating an ink ejection signal to the recording head10, are provided in front of the FPC restriction member27substantially in parallel with a virtual extension line of the ink supply tubes25. One flexible printed board26is needed for each color. The flexible printed boards26are stacked by taking advantage of their thin and flat shape and are bundled into one. With their flat surface oriented in the Y direction, the flexible printed boards26bundled into one are disposed to extend in the X direction from a position that is the opposite of the position where the liquid container unit24is provided. The flexible printed board26extending in this way is connected to the recording head10of each color from a far side with respect to the housing of the carriage20. As explained above, in the printer unit3equipped with the serial-type recording head10, the ink supply tubes25and the flexible printed boards26are provided adjacently at the space in front of the carriage20and behind the liquid container unit24, which is space saving.

Assume that the carriage20located at the right-side position as illustrated inFIG. 4travels leftward for scanning, and recording with this leftward scan is performed on the medium P that is transported. As the carriage20travels, the ink supply tubes25extending from the right moves while stretching out its upward-bent U-shaped portion leftward. Conversely, since the flexible printed boards26extend from the left, the slack of the flexible printed boards26becomes greater in the depth direction of the apparatus as the carriage20travels. When the slackening occurs, there is a risk that the flexible printed boards26with the slack might be run over by the carriage20coming from the right, resulting in damage. To avoid this from happening, the FPC restriction member27, which has a plate-like portion extending vertically down with respect to the ink supply tubes25, prevents the flexible printed boards26with increasing slackness from getting into the scan space of the carriage20while the carriage20travels.

As illustrated inFIG. 3, the printer unit3has a lower cover7at the lower portion of the front of the housing2. The lower cover7has a pivot shaft7aalong the X direction at the lower-end portion of the lower cover7. The upper-end portion of the lower cover7is a free end7b. The lower tray30containing the medium P before recording is drawn out when the free end7bof the lower cover7is pulled while being opened frontward. With the lower cover7opened, the user is able to access the upper tray31located at a rear position inside the apparatus.

In the printer unit3, the lower tray30and the upper tray31of the medium feeding unit32are able to accommodate a plurality of sheets of the medium P and are detachable from the housing2. The lower tray30and the upper tray31can be used selectively depending on the size of the medium P. In the ink-jet multifunction printer1according to the present embodiment, the lower tray30is able to contain, for example, A4-sized plain paper, glossy paper for photo use, thick paper such as cardboard paper, thin paper thinner than plain paper, and recording can be performed thereon. The upper tray31is able to contain, for example, thick paper such as postcards or envelopes, L-sized glossy paper for photo use, and recording can be performed thereon. Moreover, if a non-illustrated CD tray that comes as an accessory of the apparatus is inserted from the front of the opened lower cover7, it is possible to perform recording on a label surface of a disc-type medium such as CD or DVD.

A sheet ejection tray12for receiving the medium P ejected after recording can be opened when the lower cover7is in an open state. The sheet ejection tray12is switchable between a housed state, namely, a state of being housed inside the housing2, and a protruding state, namely, a state of protruding from the front of the housing2. In the protruding state, the sheet ejection tray12is able to receive the medium P after recording. The sheet ejection tray12is able to be switched between the housed state and the protruding state by a driving source that is not illustrated.

A pickup roller28a, which is driven to rotate by a non-illustrated motor that is a component of the medium feeding unit32, is provided. The pickup roller28ais provided on a pivot movement member28configured to pivot on a pivot shaft28b. When the upper tray31is located at a position where sheet feeding can be performed, the pickup roller28arotates while being in contact with the top one of sheets of the medium P contained in the upper tray31, thereby picking up the top one of sheets of the medium P out of the upper tray31and feeding it out onto a sheet feeding path. If, for example, the upper tray31is not attached, the pickup roller28arotates while being in contact with the top one of sheets of the medium P contained in the lower tray30, thereby picking up the top one of sheets of the medium P out of the lower tray30.

The medium P picked up is not always in a single-sheet separated state. To provide a solution for a case where multiple sheets of the medium P are picked up, a sheet separator11is provided at a position facing the leading edge of the medium P contained in the lower tray30and facing the leading edge of the medium P contained in the upper tray31. The leading edge of the medium P picked up from the lower tray30or the upper tray31due to rotation of the pickup roller28acomes into contact with the sheet separator11, and the medium P is fed downstream along the sheet feeding path while being in contact with the sheet separator11. As a result, the top sheet of the medium P is separated from the rest by the sheet separator11. The medium P goes around a feeding roller13to pass through a nip between a first feeding driven roller14aand the feeding roller13and next through a nip between a second feeding driven roller14band the feeding roller13. Then, the medium P is fed to the transportation unit33.

The transportation unit33includes a transportation drive roller15, which is driven by a non-illustrated motor, and a transportation driven roller16, which is in pressed contact with the transportation drive roller15and rotates together therewith by receiving a rotation force. The transportation unit33transports the medium P to the recording unit8located downstream thereof.

The carriage20of the recording unit8includes a gap adjuster94configured to change a gap between the recording head10and a supporting surface17for supporting the medium P at a position facing the recording head10. As will be described in detail later, the gap adjuster94is a mechanism for adjustment into an optimum gap that is the best for reducing the scratching of the medium P with the recording head10and outputting a high-quality image, which is achieved by changing the position of the carriage20in the vertical direction depending on a different thickness of the medium P.

As illustrated inFIG. 4, the carriage20of the recording unit8is provided slidably on a guide member66, which extends in the width direction and guides the carriage20in the width direction. Driven by a drive motor55, the carriage20is able to scan the recording head10in the width direction of the medium P. The medium P is fed to the supporting surface17for supporting the medium P, and the carriage20is scanned in one direction while ejecting ink from the recording head10. The medium P is fed forward, and the carriage20is scanned in the other direction while ejecting ink from the recording head10. Recording is performed by repeating these operations.

As illustrated inFIG. 3, the medium P after recording by the recording unit8is nipped between a first roller52and a second roller54and is ejected onto the sheet ejection tray12that is in a state of protruding from the front of the housing2. If double-sided printing is performed on the medium P, after completion of recording on the first side of the medium P by the recording unit8, the medium P is transported in the opposite direction by the transportation unit33. That is, before the sheet ejection tray12is completely ejected, the medium P is transported in the direction that is the opposite of the transportation direction while being nipped between the first roller52and the second roller54. When this reverse transportation is performed, the trailing edge of the medium P turns into the leading edge, and the medium P is transported toward the medium feeding unit32, which is located at the side that is the opposite of the side in the transportation direction.

The medium P is fed again while being nipped between a refeeding roller18and the feeding roller13of the medium feeding unit32. The medium P goes around the feeding roller13while being nipped by rollers arranged around the feeding roller13, specifically, first by the refeeding roller18, next by the first feeding driven roller14a, and next by the second feeding driven roller14b. By going around the feeding roller13in this way, the medium P is turned over, meaning that the second side that is the back of the first side faces up. Then, the medium P is transported to the recording unit8by the transportation unit33. Recording is performed on the second side by the recording head10. After the recording, the medium P is ejected onto the sheet ejection tray12provided at the front portion of the apparatus.

Gap Adjuster

An overview explanation of a gap adjuster is given first with reference toFIG. 5. The gap adjuster94is provided at an engagement portion where a portion protruding rearward from the back88of the housing of the carriage20is engaged with the guide member66provided behind this portion. The carriage20on which the recording head10is mounted is supported by the guide member66via the gap adjuster94. The guide member66is fastened with screws to a non-illustrated apparatus frame provided behind it. The guide member66includes a guide slide surface70, which extends in the width direction and forms the bottom surface of the guide member66, a guide supporting surface72rising in the Z direction from the rear end of the guide slide surface70, a guide surface74arising in the Z direction from the front end of the guide slide surface70, and a restriction surface76extending rearward from the upper end of the guide surface74a.

A plate-shaped back member74, as a part of the guide member66, is in contact with the back88of the housing of the carriage20and has the guide surface74aon its back. The place where the gap adjuster94is provided has a structure of protruding rearward from the back88of the housing of the carriage20to cover the back member74and extending to a position near the guide slide surface70, thereby being surrounded by walls in the Y direction and the Z direction. This engagement portion surrounded by walls on four sides between the back88of the housing of the carriage20and the guide member66will be hereinafter referred to as a house portion89. The gap adjuster94is built in the house portion89.

The gap adjuster94includes a slide member114that slides while being in contact with the guide slide surface70. The gap adjuster94further includes a receiving surface90that is an inner wall facing the back88of the housing of the carriage20in the house portion89, in addition to the slide member114. As illustrated inFIG. 7, the gap adjuster94includes a coil spring150sandwiched between the slide member114and the receiving surface90. The coil spring150is an example of a first urging member. Therefore, the receiving surface90that is the inner wall of the house portion89as a part of the carriage20is able to reciprocate the gap adjuster94together with the carriage20in the width direction while being urged with respect to the slide member114by the coil spring150in the direction that is the opposite of the transportation direction.

FIG. 6is an overall perspective view of the gap adjuster94taken out of the house portion89.FIG. 7is an exploded perspective view of the gap adjuster94illustrated inFIG. 6, shown with parts taken apart.FIG. 8is a plan view of a cam member116described later, viewed in the direction that is the opposite of the transportation direction. With reference toFIGS. 5 to 8, the structure and operation of the gap adjuster94will now be explained. As illustrated inFIG. 7, the gap adjuster94includes the slide member114, the receiving surface90, the coil spring150, the cam member116, and an engagement member118. The cam member116is in engagement between the slide member114and the receiving surface90. The engagement member118is engaged with the cam member116. The front of the slide member114is in contact with the guide surface74athat is the back of the back member74that is a part of the guide member66. The slide member114has two engagement portions124like two flights of steps at its back next to each other in the width direction. A first engagement pin126to be inserted through a cutout portion126aof the cam member116, which is located behind the slide member114, is provided at a position between the two stairway-like engagement portions124. The slide member114has a contact portion130on its top extending further up from the end face of the top one of the steps of each of the two stairway-like engagement portions124.

The slide member114has a pair of protrusions120at its left and right ends in its rear portion. The protrusion120protrudes in the direction that is the opposite of the transportation direction. The protrusion120is inserted into the coil spring150. The end of the pair of coil springs150is capped with a left-and-right pair of slide contact members115each having a shape of a cap. The head of the slide contact member115has a sliding surface91for sliding on the receiving surface90of the carriage20. As illustrated inFIG. 5, the receiving surface90of the carriage20slides on the slide contact member115smoothly in the Z direction at the time of adjusting the gap between the supporting surface17, which supports the medium P, and the recording head10. Such smooth Z-directional sliding prevents the coil spring150from buckling.

A tension spring128that is an example of a second urging member is provided over each of portions protruding up from the left and right ends of the slide member114. The tension spring128urges the slide member114with respect to the carriage20in the vertical direction that is an example of a first direction. A first hook portion132for providing a hook for the tension spring128is provided on each of the portions protruding up from the left and right ends of the slide member114. The first hook portion132is an example of a first connection portion. As illustrated inFIG. 5, one end of the tension spring128is hooked on the first hook portion132on the top end portion of the slide member114. Second hook portions133are provided on left and right outer walls of the house portion89of the carriage20. The other end of the tension spring128is hooked on the second hook portion133. The second hook portion133is an example of a second connection portion. Since the coil spring150provided on the slide member114always urges the receiving surface90of the carriage20, there is possibility that a smooth change in position of the carriage20in the Z direction is obstructed when the gap is adjusted into a certain gap value. To prevent this state, the tension spring128is provided on the first hook portion132, which is connected to the slide member114, and on the second hook portion133. The tension spring128always urges the carriage20anchored to the slide member114upward. Therefore, the carriage20is able to change its position in the Z direction smoothly on the slide contact member115provided on the slide member114.

The slide member114is pressed against the guide slide surface70of the guide member66due to the own weight of the carriage20. This prevents the carriage20from becoming ungrounded from the guide slide surface70when the carriage20reciprocates in the X direction. As illustrated inFIG. 5, in a default state, the second hook portions133provided on the left and right outer walls of the house portion89of the carriage20are configured to enable hooking thereon along the vertical direction with respect to the first hook portions132of the slide member114. However, as indicated by the broken-line illustration inFIG. 5, the second hook portions133provided on the left and right outer walls of the house portion89of the carriage20may be configured to enable hooking thereon at comparatively rear position with respect to the first hook portions132of the slide member114. That is, the tension springs128are inclined upstream in the transportation direction from the first hook portions132of the slide member114and are hooked on the second hook portions133provided on the left and right outer walls of the house portion89of the carriage20. Due to the resilience of the tension spring128hooked on the second hook portion133at the comparatively rear position of the carriage20, this produces an urging force in the direction that is the opposite of the transportation direction via the first hook portion132of the slide member114. That is, the tension spring128is able to assist in urging the receiving surface90of the carriage20in the direction that is the opposite of the transportation direction by the coil spring150provided on the slide member114.

A lubricant may be applied to the sliding surface91in order to improve the ease of sliding. As illustrated inFIG. 14, the sliding surface91may have a groove91afor retaining a lubricant as an example of a structure for always supplying a lubricant to the sliding surface91. As another example of a structure, though not illustrated in the drawing, one or more recessed pit portions may be provided in the sliding surface91so as to improve the ease of sliding.

As still another example of a structure, the ease of sliding may be improved by providing a concave portion91bextending in the vertical direction in the sliding surface91as an example of one surface and by providing a convex portion90bon the receiving surface90as an example of the other surface for mating with the concave portion91bas illustrated inFIG. 15. The opposite pattern is also possible. Though not illustrated, the ease of sliding may be improved by providing a concave portion extending in the vertical direction in the receiving surface90as an example of one surface and by providing a convex portion on the sliding surface91as an example of the other surface for mating with the concave portion. As still another example of a structure, the ease of sliding may be improved by forming an arc-curved convex sliding surface91as an example of one surface and by forming an arc-curved concave receiving surface90as an example of the other surface for mating with the sliding surface91as illustrated inFIG. 16. The opposite pattern is also possible. Though not illustrated, the ease of sliding may be improved by forming an arc-curved convex receiving surface90as an example of one surface and by forming an arc-curved concave sliding surface91as an example of the other surface for mating with the receiving surface90.

In the present embodiment, the load of the left one of the coil springs150is the same as the load of the right one. However, springs with spring constants different from each other may be used for the coil springs150. If the load of the left one of the coil springs150is the same as the load of the right one as in the present embodiment, operating noise produced at the time of gap adjustment tends to be large. Specifically, the urging force of the left one of the coil springs150and the urging force of the right one of the coil springs150provide support for maintaining the gap between the supporting surface17, which supports the medium P, and the recording head10by a left-and-right pair of stepped portions138of the cam member116, which will be described later, and by two contact portions130of the slide member114, which are engaged with the stepped portions138. Therefore, if the load of the left one of the coil springs150is the same as the load of the right one, falling from a step on the left side and from a step on the right side occurs simultaneously at the two contact portions130engaged with the stepped portions138, resulting in large falling noise. By contrast, if the urging forces applied by the coil springs150at the respective ends of the slide member114in the width direction are different from each other, falling at the contact portions130occurs non-simultaneously for the left one and the right one of the pair of stepped portions138of the cam member116. Since the left fall and the right fall do not occur simultaneously, it is possible to make the timing of generation of falling noise asynchronous. Therefore, it is possible to make falling noise generated during the operation of the gap adjuster94smaller.

As illustrated inFIGS. 5, 6, and 7, the cam member116arranged behind the slide member114is located between the receiving surface90of the carriage20and the slide member114. As illustrated inFIG. 8, the cam member116has the left-and-right pair of stepped portions138with alternate-arrangement structure in the width direction on its side of contact with the slide member114. A second engagement pin136is provided on a lowest end portion extending further down from the end face of the lowest one of the steps of each of the two the stepped portions138. As illustrated inFIG. 7, the second engagement pin136is engaged with the stairway-like engagement portion124of the slide member114and enables the cam member116to slide in the X direction. The cam member116further has a pair of upper engagement portions142on the left and right ends of its top. As illustrated inFIG. 9, the upper engagement portion142is engaged with a guide groove89a, which is provided at the top portion of the house portion89of the carriage20along the X direction, so as to prevent the cam member116from coming off from the house portion89of the carriage20.

As illustrated inFIG. 7, the engagement member118arranged behind the cam member116has a guide groove144, which extends in the X direction, and an elongated hole146, which extends in the Z direction with X-directional inclination. As illustrated inFIG. 6, the first engagement pin126of the slide member114is engaged with the guide groove144of the engagement member118through the cutout portion126aof the cam member116. As illustrated inFIG. 7, the cam member116has a third engagement pin140on its side that is the opposite of the side of contact with the slide member114. The third engagement pin140of the cam member116is engaged with the elongated hole146of the engagement member118.

Since the first engagement pin126of the slide member114is engaged with the guide groove144of the engagement member118as illustrated inFIG. 6, the position of the engagement member118and the slide member114does not change in the Z direction when the engagement member118is slid in the X direction. However, the cam member116moves in the Z direction with X-directionally-inclined operation of the third engagement pin140along the elongated hole146of the engagement member118. Namely, the sliding of the engagement member118causes the movement of the cam member116and the engagement member118together in the X direction and causes a change in position of the cam member116only in the Z direction by an amount corresponding to the height of the elongated hole146approximately. The change in position in the Z direction is a change in height level of the second engagement pin136of the cam member116from the lowest one to the top one of the steps of the stairway-like engagement portion124of the slide member114.

As illustrated inFIGS. 6 and 7, the gap adjuster94fulfills its function by combination of the slide member114, the cam member116, and the engagement member118. The power of a motor is transmitted via a non-illustrated pinion gear engaged with a rack100provided on the top surface of the cam member116. Gap adjustment is performed by receiving this motor power. A case where, for example, the gap between the supporting surface17, which supports the medium P, and the recording head10is increased by moving the cam member116in the direction from the tail toward the head of the X-directional arrow will now be described.

The motor power transmitted via the pinion gear to the rack100causes the cam member116to move in the X direction. The cam member116is able to move in the X direction by a movement distance corresponding to the length of the guide groove89a, which is provided at the top portion of the house portion89of the carriage20along the X direction. When the cam member116moves in the X direction, the cam member116causes its second engagement pin136to change in position upward while being in engagement with the stairway-like engagement portion124of the slide member114. As mentioned earlier, the upper engagement portion142of the cam member116is engaged with the house portion89of the carriage20. Therefore, the carriage20changes in position upward together with the cam member116.

With reference toFIGS. 8 to 13, the gap adjusted by operation of the gap adjuster94between the supporting surface17, which supports the medium P, and the recording head10will now be explained. The gap adjuster94has the same stepped structure on its left portion and right portion as described above and causes these two sets of the structure to perform the same operation abreast with each other. Therefore, an explanation is given below for one set only. The gap adjuster94illustrated inFIGS. 9 to 13are shown at a cross section taken along the X-directional line IX-IX to XIII-XIII ofFIG. 6.

As illustrated inFIG. 8, the cam member116has a cam portion on its side of contact with the slide member114, wherein the cam portion includes the stepped portion138with level differences in the vertical direction, with alternate slope and non-slope arrangement in the width direction. The stepped portion138of the cam member116is made up of keeping surfaces for keeping the carriage position in the vertical direction and adjustment surfaces for sloped connection between these keeping surfaces and for changing the carriage position in the vertical direction. More specifically, the stepped portion138includes a first level portion138a, a second level portion138c, a third level portion138e, a fourth level portion138g, and a fifth level portion138ias surfaces for keeping the gap, and includes a first sloped portion138b, a second sloped portion138d, a third sloped portion138f, and a fourth sloped portion138has surfaces for adjusting the gap. The level portions138a,138c,138e,138g, and138iand the sloped portions138b,138d,138f, and138hare arranged alternately in the width direction to constitute the stepped structure.

Any one of the first level portion138a, the second level portion138c, the third level portion138e, the fourth level portion138g, and the fifth level portion138iengages with the contact portion130of the slide member114to define the gap and keep the gap. The first sloped portion138b, the second sloped portion138d, the third sloped portion138f, and the fourth sloped portion138hchange the gap when the cam member116slides with respect to the slide member114.

The contact portion130comes into engagement with the level portions138a,138c,138e,138g, and138iin this order when the cam member116slides with respect to the slide member114in the X direction. The contact portion130comes into engagement with the level portions138i,138g,138e,138c, and138ain this order when the cam member116slides with respect to the slide member114in the opposite direction along the X direction. By this means, it is possible to change the gap distance.

Next, each gap will now be explained.FIG. 9illustrates a state in which the first level portion138aof the stepped portion138of the cam member116is in contact with the contact portion130of the slide member114. When in this state, the height of the first level portion138ain the Z direction specifies the minimum setting of the gap between the recording head10and the supporting surface17for supporting the medium P. This gap is set when, for example, recording is performed on glossy paper for photo use.

Next,FIG. 10illustrates a state in which the second level portion138cof the stepped portion138of the cam member116is in contact with the contact portion130of the slide member114. When in this state, the height of the second level portion138cin the Z direction specifies that the position of the carriage20is changed up by one step from the minimum setting of the gap between the recording head10and the supporting surface17for supporting the medium P. This gap is set when, for example, recording is performed on plain paper. In addition, this gap is set in order to avoid so-called scratching if the scratching contact of the recording head10has occurred in recording performed on glossy paper for photo use with the minimum setting.

Next,FIG. 11illustrates a state in which the third level portion138eof the stepped portion138of the cam member116is in contact with the contact portion130of the slide member114. When in this state, the height of the third level portion138ein the Z direction specifies that the position of the carriage20is changed up by two steps from the minimum setting of the gap between the recording head10and the supporting surface17for supporting the medium P. For example, this gap is set in order to avoid scratching if scratching contact has occurred in recording performed on plain paper with the one-step-raised setting described above.

Next,FIG. 12illustrates a state in which the fourth level portion138gof the stepped portion138of the cam member116is in contact with the contact portion130of the slide member114. When in this state, the height of the fourth level portion138gin the Z direction specifies that the position of the carriage20is changed up by three steps from the minimum setting of the gap between the recording head10and the supporting surface17for supporting the medium P. This gap is set when, for example, recording is performed on thick paper such as cardboard paper.

Next,FIG. 13illustrates a state in which the fifth level portion138iof the stepped portion138of the cam member116is in contact with the contact portion130of the slide member114. When in this state, the height of the fifth level portion138iin the Z direction specifies the maximum setting of the gap between the recording head10and the supporting surface17for supporting the medium P. This gap is set when, for example, label recording is performed on CD, etc.

As illustrated inFIG. 17, in the gap adjuster94according to the present embodiment, moment that is applied to an upper supporting surface66aextending vertically down in the direction of gravity from the upper portion of the guide member66and applied to an upper slide surface20aof the carriage20that is in contact with the upper supporting surface66achanges due to the change in position of the carriage20in the Z direction. For example, suppose that the position of the carriage20changes in the Z direction from the position indicated by solid-line illustration to broken-line illustration inFIG. 17due to gap adjustment. The center of gravity MG1of the carriage20changes to the center of gravity MG2. Since the fulcrum of rotation, on the upper slide surface20a, remains the same, the length of the line segment connecting the upper slide surface20ato the center of gravity MG2is greater than the length of the line segment connecting the upper slide surface20ato the center of gravity MG1. This means that the moment changes as a result of the change in position of the carriage20in the Z direction. For this reason, if the urging force of the coil spring150applied to the receiving surface90of the carriage20does not change, the moment applied to the carriage20changes. In order to keep the moment applied to the carriage20by the gap adjuster94constant, steps in the Z direction, which is an example of a first direction, are provided in the receiving surface90of the house portion89of the carriage20. By this means, the gap adjuster94is able to balance the moment applied to the carriage20by increasing or decreasing the urging force of the coil spring150in relation to the change in position of the carriage20in the Z direction.

As explained above, the following effects can be obtained from the ink-jet multifunction printer1according to an exemplary embodiment of the present disclosure. In the ink-jet multifunction printer1, the guide member66extending in the width direction is provided, and the recording head10mounted on the carriage20performs recording on the medium P supported on the supporting surface17while the carriage20is scanned in the width direction. The ink-jet multifunction printer1includes the gap adjuster94. The gap adjuster94changes in the vertical direction a gap between the recording head10and the supporting surface17, which is a surface for supporting the medium P at a position facing the recording head10. The gap adjuster94includes the slide member114and the cam member116. The slide member114moves in the width direction together with the carriage20. The cam member116is provided between the carriage20and the slide member114and has the stepped portion138in which keeping surfaces and adjustment surfaces are arranged alternately in the width direction. The slide member114of the gap adjuster94has the pair of protrusions120at its left and right ends in its rear portion. The coil springs150are provided around the protrusions120. The coil springs150urge the carriage20with respect to the slide member114in the direction that is the opposite of the transportation direction.

In the ink-jet multifunction printer1, the slide contact member115is provided between the end of each coil spring150of the slide member114and the receiving surface90of the carriage20. This structure prevents the end of the coil spring150from getting caught on the receiving surface90of the carriage20. Therefore, the gap between the recording head10and the supporting surface17for supporting the medium P is made stable, resulting in improved print quality.

In the ink-jet multifunction printer1, the protrusions120provided on the slide member114protrude into the coil springs150respectively. This structure reduces a relative deviation of the central axes of the slide contact member115and the coil spring150. Furthermore, this structure makes the coil spring150unlikely to buckle when gap adjustment is performed, and makes the gap between the recording head10and the supporting surface17for supporting the medium P stable, resulting in improved print quality.

In the ink-jet multifunction printer1, the slide contact member115is provided between the end of each coil spring150of the slide member114and the receiving surface90of the carriage20. A groove for retaining a lubricant is provided in the sliding surface91of the slide contact member115that is in sliding contact with the receiving surface90of the carriage20. Since the groove is provided, in the ink-jet multifunction printer1, a lubricant is applied between the receiving surface90of the carriage20and the sliding surface91of the slide contact member115, and the lubricant reduces a friction coefficient and thus makes it possible to perform smooth sliding. Therefore, the gap between the recording head10and the supporting surface17for supporting the medium P is made stable, resulting in improved print quality.

In the ink-jet multifunction printer1, the center of gravity of the carriage20changes as a result of changing the position of the carriage20by the gap adjuster94. However, the fulcrum of rotation, on the upper slide surface20a, remains the same. Therefore, a moment expressed as a line segment connecting the fulcrum of rotation, on the upper slide surface20a, to the center of gravity of the carriage20changes. If there were no change in the urging force of the coil spring150applied to the receiving surface90of the carriage20despite the fact that the moment changes due to the change in the position of the carriage20in the Z direction, the moment applied to the carriage20would not be constant. For a solution, steps in the Z direction are provided in the receiving surface90of the carriage20. By this means, the ink-jet multifunction printer1is able to balance the moment applied to the carriage20by increasing or decreasing the urging force of the coil spring150in relation to the change in position of the carriage20in the Z direction. Therefore, the gap between the recording head10and the supporting surface17for supporting the medium P is made stable, resulting in improved print quality.

In the ink-jet multifunction printer1, either a concave portion extending in the vertical direction or a convex portion extending in the vertical direction is provided in or on one of the sliding surface91of the slide contact member115and the receiving surface90of the carriage20, and the concave portion and the convex portion mate with each other. This structure prevents the slide contact member115from getting caught on the receiving surface90of the carriage20. Therefore, the gap between the recording head10and the supporting surface17for supporting the medium P is made stable, resulting in improved print quality.

In the ink-jet multifunction printer1, the slide contact member115is provided between the end of each coil spring150of the slide member114and the receiving surface90of the carriage20. The ink-jet multifunction printer1has a shape for reducing a friction coefficient between the sliding surface91of the slide contact member115and the receiving surface90. In the ink-jet multifunction printer1, either an arc-curved convex surface or an arc-curved concave surface is provided on or in one of the sliding surface91of the slide contact member115and the receiving surface90of the carriage20, and the arc-curved convex surface and the arc-curved concave surface mate with each other. This structure prevents the sliding surface91of the slide contact member115from getting caught on the receiving surface90of the carriage20. Therefore, the gap between the recording head10and the supporting surface17for supporting the medium P is made stable, resulting in improved print quality.

In the ink-jet multifunction printer1, the tension spring128, which urges the slide member114with respect to the carriage20in the vertical direction, is provided as an example of a second urging member over each of portions protruding up from the left and right ends of the slide member114of the gap adjuster94. However, if an urging force of urging the carriage20is insufficient, in the ink-jet multifunction printer1, the second hook portion133provided on the outer wall of the house portion89of the carriage20may be provided at such a position that the tension spring128is hooked thereon with upstream inclination in the transportation direction with respect to the vertical direction. Due to the resilience of the tension spring128hooked on the second hook portion133at the comparatively rear position of the carriage20, this produces an urging force in the direction that is the opposite of the transportation direction via the first hook portion132of the slide member114. That is, the tension spring128is able to assist in urging the receiving surface90of the carriage20in the direction that is the opposite of the transportation direction by the coil spring150provided on the slide member114. Therefore, the gap between the recording head10and the supporting surface17for supporting the medium P is made stable, resulting in improved print quality.

In the ink-jet multifunction printer1, normally, the carriage20is supported by means of urging forces applied by the left-and-right pair of coil springs150, and the urging force of the left one of the coil springs150and the urging force of the right one of the coil springs150provide support for maintaining the gap between the supporting surface17, which supports the medium P, and the recording head10by the left-and-right pair of stepped portions138of the cam member116and by the two contact portions130of the slide member114, which are engaged with the stepped portions138. Therefore, if the load of the left one of the coil springs150is the same as the load of the right one, large falling noise will be produced when falling from a step on the left side and from a step on the right side occurs simultaneously at the two contact portions130engaged with the stepped portions138.

In the ink-jet multifunction printer1, spring constants, etc. are made different from each other so that the urging forces applied by the coil springs150at the respective ends of the slide member114in the width direction will be different from each other, and, accordingly, falling at the contact portions130occurs non-simultaneously for the left one and the right one of the pair of stepped portions138of the cam member116. Since the left fall and the right fall do not occur simultaneously, it is possible to make the timing of generation of falling noise asynchronous. For this reason, the ink-jet multifunction printer1makes it possible to make falling noise that is generated during the operation of the gap adjuster94smaller. Therefore, the ink-jet multifunction printer1realizes a reduction in noise that will make the user feel uncomfortable.