Linear motion telescopic device, maintenance device and image forming device

Abstract

The linear motion telescopic device (21) has a plurality of rod-shaped parts (31) arranged in a row to form a support arm (30); and a rotating plate (42) which rotates in a winding direction to rotate the plurality of rod-shaped parts (31) through a connecting rotating shaft (32) while winding them, and rotates in a delivery direction to push the plurality of rod-shaped parts (31) in a row, wherein the rod-shaped parts (31) have an intermediate shaft (33) and an angle limiting portion (34) which limits the expansion from the winding state to a predetermined angle or more, and the rotating plate (42) has a plurality of engaging grooves (44) for engaging the connecting rotating shaft (32) and the intermediate shaft (33), and when the rotating plate (42) rotates in the delivery direction, the connecting rotating shaft (32) and the intermediate shaft (33) are pushed toward the downstream side of the forward and backward direction by contacting the inner surface (45) of the engaging groove (44), thereby disengaging from the engaging groove (44).

Description

Technical Field

[0001] The invention relates to a linear motion telescopic device, a maintenance device and an image forming device. Background Art

[0002] A conveyor chain is disclosed (Patent Document 1) which is composed of a plurality of inner link plates and a pair of outer link plates connected by connecting pins and is used to convey a conveyance object in a conveying direction.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-189404 Summary of the Invention

[0006] [Technical problem to be solved by the invention]

[0007] In conveyor chains, because multiple inner and outer links are connected, minute play at the connecting parts can accumulate, potentially leading to significant errors overall. Consequently, conveyed items may not be accurately delivered to the desired position.

[0008] In order to solve the above-mentioned problems, the present invention provides a linear motion telescopic device, a maintenance device, and an image forming apparatus capable of improving positional accuracy in the forward and backward directions.

[0009] [Technical solutions for solving technical problems]

[0010] The linear motion telescopic device of the present invention is characterized in that it comprises a plurality of rod-like components and a rotating plate, wherein the rod-like components are rotatably connected via a connecting rotating shaft and are arranged in a row in a direction orthogonal to the connecting rotating shaft to form a supporting arm; the rotating plate is arranged in a manner capable of rotating around a main rotating shaft, and the rod-like component located at the first end of the supporting arm is connected to the radially outer side of the main rotating shaft via a base end pin, and the plurality of rod-like components are wound while being rotated by the connecting rotating shaft by the rotating plate, and the plurality of rod-like components are wound while being rotated by the rotating plate in a sending direction which is a direction opposite to the winding direction. The rod-shaped component is pushed out in a row, and the rod-shaped component has an intermediate shaft and an angle limiting portion, wherein the intermediate shaft is set in a manner parallel to the connecting rotating shaft; the angle limiting portion limits the expansion from the wound state to above a specified angle by abutting against the adjacent rod-shaped component when the support arm is formed, and the rotating plate has a plurality of engaging grooves, which are cut from the radial outside to the inside, and engage with the connecting rotating shafts and the intermediate shaft of the plurality of rod-shaped components wound. When the rotating plate rotates in the sending direction, the connecting rotating shaft and the intermediate shaft are pushed out of the engaging groove by contacting the inner surface of the engaging groove, thereby disengaging from the engaging groove.

[0011] The maintenance device of the present invention includes the above-mentioned linear motion telescopic device and a maintenance unit, wherein the maintenance unit is moved in the forward and backward directions by the linear motion telescopic device to prevent or repair clogging of the discharge nozzle that discharges liquid from the discharge nozzle.

[0012] The image forming apparatus of the present invention includes the above-mentioned maintenance device.

[0013] [Effects of the Invention]

[0014] According to the present invention, the position accuracy in the forward and backward directions can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram (front view) showing the internal structure of an image forming apparatus according to one embodiment of the present invention.

[0016] Figure 2 It is a perspective view showing a maintenance device according to one embodiment of the present invention.

[0017] Figure 3 It is a perspective view showing the maintenance device (at the push-out position) according to one embodiment of the present invention.

[0018] Figure 4 It is a perspective view showing a linear motion expansion and contraction device according to one embodiment of the present invention.

[0019] Figure 5 This is a perspective view showing the bottom side of the linear motion telescopic device (in a state where a support arm is formed) according to one embodiment of the present invention.

[0020] Figure 6 It is a perspective view showing the upper side of the linear motion expansion and contraction device according to one embodiment of the present invention.

[0021] Figure 7 It is a perspective view showing the bottom side of the linear motion expansion and contraction device according to one embodiment of the present invention.

[0022] Figure 8 This is a perspective view showing a state in which the intermediate shaft at the top end of the linear motion expansion and contraction device according to one embodiment of the present invention is pushed out.

[0023] Figure 9 This is a perspective view showing a state in which the second intermediate shaft is pushed out of the linear motion expansion and contraction device according to one embodiment of the present invention.

[0024] Figure 10 This is a perspective view showing a state in which the connected rotating shaft of the linear motion expansion and contraction device according to one embodiment of the present invention is pushed out.

[0025] Figure 11 This is a perspective view showing a state where a support arm of a linear motion expansion and contraction device according to an embodiment of the present invention is formed.

[0026] Figure 12 This is a perspective view illustrating the action of the elastic member in a state where the support arm of the linear motion expansion and contraction device according to one embodiment of the present invention is formed. DETAILED DESCRIPTION

[0027] Preferred embodiments of the present invention are described below with reference to the accompanying drawings. In the accompanying drawings, Fr, Rr, L, R, U, and D represent front, rear, left, right, up, and down. Terms indicating directions and positions are used in this specification for convenience only and do not limit the technical scope of the present invention.

[0028] [Overview of Image Forming Apparatus]

[0029] Reference Figure 1 The image forming apparatus 1 will be described. Figure 1 It is a schematic diagram (front view) showing the internal structure of the image forming apparatus 1 .

[0030] Image forming apparatus 1 is an inkjet printer that forms an image on a sheet S by ejecting ink droplets. Image forming apparatus 1 includes a box-shaped housing 2 that houses various components. A paper feed cassette 3A for placing sheets S is located at the bottom of housing 2. A manual feed tray 3B for manually placing sheets S is located on the right side of housing 2. A paper output tray 4 is located on the upper left side of housing 2, where sheets S on which image formation has been completed are loaded.

[0031] A first conveyance path 5 is formed on the right side of the housing 2 for conveying sheets S from the paper feed cassette 3A to the image forming unit 12 located approximately in the center of the housing 2. A paper feed unit 10A is provided upstream of the first conveyance path 5, and a resist roller 11 is provided downstream of the first conveyance path 5. Furthermore, the downstream portion of the first conveyance path 5 is connected to a paper feed path 6 for the manual paper feed tray 3B, and a paper feed unit 10B is provided on the paper feed path 6. The paper feed unit 10A has the function of removing sheets S from the stack of sheets in the paper feed cassette 3A, while the paper feed unit 10B has the function of removing sheets S from the stack of sheets in the manual paper feed tray 3B.

[0032] The image forming unit 12 is equipped with multiple (e.g., four) line heads 13 that eject ink droplets. Each line head 13 is equipped with multiple ejection heads 13A corresponding to four colors of ink: black, cyan, magenta, and yellow. Each ejection head 13A has a nozzle face (not shown) formed by multiple ejection nozzles (not shown), and ejects ink (liquid) from the ejection nozzles. Furthermore, each ejection head 13A is connected to an ink pack (not shown) containing each color of ink via a hose (not shown), and ink is supplied from the ink pack to the ejection head 13A.

[0033] The conveyor belt 14 is suspended on a plurality of suspension rollers 14A disposed below the image forming section 12. The conveyor belt 14 has a plurality of through-holes (not shown). A suction portion 14B is provided on the inner side of the conveyor belt 14, facing the image forming section 12, to generate negative pressure in the through-holes of the conveyor belt 14. A decurling device 15 is provided on the left side (downstream in the conveyance direction) of the image forming section 12 to correct curl in the sheet S by clamping the sheet S while conveying it.

[0034] A second conveyance path 7 is formed on the left side of the housing 2 to convey sheets S from the decurling device 15 to the paper discharge tray 4. A branching member 9 is provided in the middle of the second conveyance path 7, and a paper discharge unit 16 is provided downstream of the second conveyance path 7. The branching member 9 switches the discharge destination of the sheets S between the paper discharge tray 4 and the third conveyance path 8 (described later). The paper discharge unit 16 discharges the sheets S on which image formation has been completed to the paper discharge tray 4.

[0035] A third conveying path 8 for conveying the sheet S from the branch member 9 midway in the second conveying path 7 to the registration roller 11 is formed in the upper portion of the housing 2. A reversing section 17 for reversing the sheet S is provided midway in the third conveying path 8.

[0036] The image forming apparatus 1 (inside the housing 2) is provided with a control unit 18 for appropriately controlling various controlled devices. The control unit 18 includes a processor that executes various calculations based on programs and parameters stored in a memory. Alternatively, the control unit 18 may be implemented as a logic circuit (hardware) formed on an integrated circuit or the like, instead of a processor that executes programs.

[0037] [Image Formation Process]

[0038] Here, refer to Figure 1 The image forming process implemented by the image forming apparatus 1 will be described. The control unit 18 appropriately controls various control target devices to execute the image forming process as follows.

[0039] The paper feed units 10A and 10B feed the sheet S taken out from the paper feed cassette 3A or the manual paper feed tray 3B to the first conveying path 5 or the paper feed path 6. The registration roller 11 temporarily blocks the sheet S before printing (for single-sided printing) and performs skew correction, and feeds the sheet S before printing to the conveyor belt 14 in a manner that aligns the ejection timing of the ink droplets ejected from the line head 13. The sheet S is adsorbed on the conveyor belt 14 and is conveyed to the downstream side by the moving conveyor belt 14. The image forming unit 12 (line head 13) ejects ink droplets onto the sheet S on the conveyor belt 14 to form (print) a full-color image. The sheet S passing from under the image forming unit 12 is released from the adsorption relative to the conveyor belt 14 and is conveyed to the decurling device 15. The decurling device 15 corrects the curl generated on the sheet S.

[0040] When single-sided printing is performed, the branching member 9 opens the second conveying path 7 and closes the third conveying path 8. The sheet S after single-sided printing is discharged to the paper output tray 4 through the second conveying path 7.

[0041] When performing duplex printing, the branching member 9 closes the second conveyance path 7 and opens the third conveyance path 8. The sheet S, which has been printed on one side, enters the third conveyance path 8, is reversed by the reversing unit 17, and is conveyed again toward the registration roller 11. An image is then formed on the back side of the sheet S in the same sequence as for single-sided printing. The curl of the duplex-printed sheet S is corrected and the sheet is discharged to the paper output tray 4.

[0042] [Maintenance device]

[0043] The inkjet image forming apparatus 1 also includes a plurality (e.g., four) of maintenance devices 20 for performing maintenance on the ejection heads 13A, for example, during a stoppage. The four maintenance devices 20 are provided to correspond to the four line heads 13. For example, each maintenance device 20 is located on the lower right side of the line head 13.

[0044] Reference Figures 1 to 3 The maintenance device 20 will be described in detail. Figure 2 and Figure 3 2 is a perspective view showing the maintenance device 20. Since the four maintenance devices 20 have substantially the same structure, one maintenance device 20 will be described below.

[0045] The maintenance device 20 has a linear motion telescopic device 21 (see Figure 3 ), the conveying structure 22 and the maintenance part 23 (refer to Figure 1 The linear motion expansion and contraction device 21 has the function of moving the maintenance unit 23 supported by the conveying structure 22 in the left-right direction (advance and retreat direction). The maintenance unit 23 has the function of preventing or repairing blockage of the ejection nozzle 13A. In addition, the linear motion expansion and contraction device 21 and the maintenance unit 23 are electrically connected to the control unit 18 and are controlled by the control unit 18.

[0046] Next, the conveying structure 22 and the maintenance unit 23 will be described before describing the linear motion expansion and contraction device 21 .

[0047] <Conveying structure>

[0048] like Figure 2 and Figure 3 As shown, the conveying structure 22 includes a frame 24 and a conveying body 25. The frame 24 is made of, for example, a metal plate and is formed into a generally box-like shape. The conveying body 25 is made of, for example, a metal plate and is formed into a generally disc-like shape (generally a flat plate). The conveying body 25 is supported so as to be slidable relative to the frame 24 via a pair of front and rear slide rails 26.

[0049] like Figure 3 As shown, the slide guide 26 includes a first guide rail 26A fixed to the inner side surface of the frame 24, a second guide rail 26B slidably supported by the first guide rail 26A, and a third guide rail 26C slidably supported by the second guide rail 26B. The third guide rail 26C is fixed to the outer side surface of the conveying body 25. The conveying body 25 is arranged in the storage position P1 set inside the frame 24 by pulling the first guide rail 26A to the third guide rail 26C to the maximum extent (see FIG. 1 ). Figure 2 On the other hand, the conveyor 25 is arranged at the push-out position P2 set outside the frame 24 by pulling out the first to third guide rails 26A to 26C to the maximum extent (see Figure 3 ).

[0050] <Maintenance Department>

[0051] like Figure 1 As shown, the maintenance unit 23 is supported on the conveying structure 22 (on the conveying body 25). The maintenance unit 23 includes, for example, an end cap unit and a wiping unit (both not shown). The end cap unit has an end cap that covers the nozzle surface of the ejection nozzle 13A. The end cap unit can prevent the dried ink or thickened ink from clogging the ejection nozzle by covering the nozzle surface with the end cap. The wiping unit has a wiper that wipes the nozzle surface of the ejection nozzle 13A. In addition to removing ink attached to the nozzle surface with the wiper, the wiping unit also removes ink clogged in the ejection nozzle, thereby repairing the clogging of the ejection nozzle 13A. In addition, the end cap unit may also include a suction mechanism (not shown) for forcibly sucking out the ink clogged in the ejection nozzle.

[0052] The conveying body 25 moves to the ejection position P2 (see Figure 3 ), the maintenance unit 23 is arranged directly below each ejection nozzle 13A constituting the line head 13. In this state, the maintenance unit 23 performs maintenance such as preventing or repairing blockage of each ejection nozzle 13A. After the maintenance operation is completed, the transport body 25 moves to the storage position P1, and the maintenance unit 23 retreats from directly below the line head 13 (ejection nozzle 13A) and is stored inside the frame 24 together with the transport body 25 (refer to Figure 1 and Figure 2 ).

[0053] <Linear Motion Telescopic Device>

[0054] Next, refer to Figures 3 to 7 The linear motion telescopic device 21 will be described. Figure 4 It is a perspective view showing the linear motion expansion and contraction device 21 . Figure 5 It is a perspective view showing the lower side of the linear motion telescopic device 21 (in a state where the support arm 30 is formed). Figure 6 It is a perspective view showing the upper side of the linear motion expansion and contraction device 21 . Figure 7 It is a perspective view showing the bottom side of the linear motion expansion and contraction device 21 .

[0055] like Figure 3 and Figure 4 As shown, the linear motion expansion and contraction device 21 includes a plurality (eg, three) of rod-shaped members 31A, 31B, and 31C, a biasing member 40 , an elastic member 41 , a rotating plate 42 , a guide member 46 , and a driving portion 51 .

[0056] (Rod-shaped parts)

[0057] like Figure 3 and Figure 5As shown, three rod-shaped members 31A, 31B, and 31C are rotatably connected via connecting rotating shafts 32A and 32B, and are arranged in a row in the left-right direction (the forward and backward direction orthogonal to the connecting rotating shaft 32) to form the support arm 30. The base end of the rod-shaped member 31A located at the most base end side of the support arm 30 is connected to the rotating plate 42 via a base end pin 30A (see also Figure 4 The distal end of the rod-shaped member 31C (top rod-shaped member) located at the distal end side of the support arm 30 (the second end opposite to the first end of the two ends of the support arm 30) is connected to the conveying body 25 via the distal end pin 30B (see Figure 3 The base pin 30A is fixed to the rotating plate 42, and the tip pin 30B is fixed to the conveying body 25. The support arm 30 (three rod-shaped members 31A, 31B, 31C) is formed to a length that allows the conveying body 25 to move from the storage position P1 to the push-out position P2.

[0058] In addition, below, in the common description of the three rod-shaped parts 31A to 31C, they are simply referred to as "rod-shaped parts 31", and the reference numerals are marked only with Arabic numerals. Similarly, in the common description of the two connecting rotating shafts 32A and 32B, they are simply referred to as "connecting rotating shafts 32", and the reference numerals are marked only with Arabic numerals. In addition, in this specification, the term "top end / base end" refers to the top end / base end in the forward and backward direction. Moreover, the downstream direction of the forward and backward direction is sometimes referred to as the "pull-out direction (left)", and the upstream direction of the forward and backward direction is sometimes referred to as the "pull-back direction (right)". In addition, in this specification, the term "clockwise / counterclockwise" is based on the rotation direction when viewed from above.

[0059] like Figure 5 and Figure 6 As shown, the rod-shaped member 31 is made of metal, for example, and has a roughly rectangular cross-section, and is formed into a rod shape extending in one direction. The ends of the rod-shaped member 31 in the longitudinal direction are formed to be thinner than the middle portion, and the ends of a pair of adjacent rod-shaped members 31 overlap with each other. Moreover, the ends (overlapping portions) of the pair of adjacent rod-shaped members 31 are connected by a connecting rotating shaft 32 that passes through in the vertical direction. The connecting rotating shaft 32 is formed into a roughly cylindrical shape, passes through the connecting portion of the rod-shaped member 31 in the vertical direction, and extends downward. The rod-shaped member 31 rotates (sways) within a predetermined range around the connecting rotating shaft 32.

[0060] like Figure 5As shown, an intermediate shaft 33A is provided approximately in the longitudinal center of the rod-shaped member 31A, parallel to the connecting rotation axis 32. Similarly, two intermediate shafts 33B and 33C are provided on the rod-shaped members 31B and 31C. Intermediate shafts 33A, 33B, and 33C are formed into a substantially cylindrical shape with approximately the same diameter as the connecting rotation axis 32. They vertically penetrate the rod-shaped member 31 and extend downward. The four intermediate shafts 33B and 33C and the connecting rotation axes 32A and 32B are arranged at approximately equal intervals in the longitudinal direction. In the following description of the intermediate shafts 33A, 33B, and 33C provided on the three rod-shaped members 31A to 31C, they will be simply referred to as "intermediate shafts 33," and reference numerals will be used.

[0061] The rod-shaped member 31 has an angle limiting portion 34, which limits the angle between the adjacent rod-shaped members 31 from the winding state (see FIG. 1 ) by contacting the adjacent rod-shaped members 31 in the state of forming the support arm 30. Figure 6 ) to a predetermined angle (rotation in the direction opposite to the rotational direction). Angle limiters 34 are formed on the lower sides of both ends of the rod-shaped member 31. The angle limiters 34 are formed into a hook shape that avoids the connecting rotation axis 32 in the direction opposite to the rotational direction. A pair of adjacent rod-shaped members 31 are restricted in rotation about the connecting rotation axis 32 by abutting each other's angle limiters 34. The angle limiters 34 limit the angle between adjacent rod-shaped members 31 so that the angle does not extend beyond a straight line. Furthermore, a straight line refers to a state where the angle is substantially 180 degrees, sufficiently close to 180 degrees within the accuracy required by the linear motion telescopic device 21. Substantially 180 degrees means, for example, 170 degrees or more and 190 degrees or less, further 175 degrees or more and 185 degrees or less, and particularly 179 degrees or more and 181 degrees or less. Specifically, the angle limiters 34 are not formed on the ends of the rod-shaped members 31A and 31C, which constitute the top and base ends of the support arm 30. In addition, in this specification, the rotation of the rod-shaped member 31 in the direction opposite to the rotation direction in the wound state is also referred to as "reverse bending" or the like.

[0062] (Force applying component)

[0063] like Figure 3 and Figure 4As shown, the force-applying member 40 is disposed between (the distal end of) the rod-shaped member 31C located at the distal end of the support arm 30 and the conveying body 25. Specifically, the force-applying member 40 is, for example, a torsion coil spring, wound around the distal pin 30B that connects the distal end of the rod-shaped member 31C to the conveying body 25. One arm of the force-applying member 40 engages with the rod-shaped member 31C, while the other arm of the force-applying member 40 engages with the cutout portion of the conveying body 25. The force-applying member 40 applies force to the rod-shaped member 31C (the distal rod-shaped member) in the reflexing direction (the direction opposite to the rotational direction in the wound state). Furthermore, the force of the force-applying member 40 is also transmitted to the other rod-shaped members 31A and 31B via the rod-shaped member 31C.

[0064] (Elastic component)

[0065] like Figure 6 As shown, the elastic member 41 is provided between the rod-shaped member 31A located at the most proximal end (first end) of the support arm 30 and the proximal end pin 30A. Specifically, the elastic member 41 is, for example, a coil spring (compression spring), and is disposed inside the long hole 35 opened at the proximal end of the rod-shaped member 31A. The long hole 35 is formed long along the longitudinal direction of the rod-shaped member 31A (see also Figure 5 A pair of protrusions 36 are provided on the upper surface of the rod-shaped member 31A so as to protrude upward along the elongated hole 35. Furthermore, a pressing plate 37 is fixed to the upper surface of the rod-shaped member 31A, closer to the distal end of the protrusions 36, to partially block the elongated hole 35. A contact portion 37A is formed on the pressing plate 37 to block the pair of protrusions 36.

[0066] The base pin 30A is inserted into the elongated hole 35 at the base end of the pair of protrusions 36. The base pin 30A moves between the pair of protrusions 36 (the contact portion 37A) and the inner surface of the base end of the elongated hole 35. The base end of the elastic member 41 contacts the base pin 30A inserted into the elongated hole 35, while the tip of the elastic member 41 contacts the inner surface of the tip end of the elongated hole 35. The rod-shaped member 31A (support arm 30) is pushed outward from the base pin 30A by the force of the elastic member 41, contacting the inner surface of the base end of the elongated hole 35. When the rod-shaped member 31A (support arm 30) is pushed inward against the force of the elastic member 41, the elastic member 41 elastically deforms (contracts), causing the base pin 30A to contact the pair of protrusions 36 and the contact portion 37A. The elastic member 41 has the function of absorbing displacement in the forward and backward directions of the support arm 30 through elastic deformation.

[0067] (rotating plate)

[0068] like Figures 5 to 7 As shown, the rotating plate 42 is made of metal and is formed into a substantially circular plate shape. The rotating plate 42 is arranged between a pair of upper and lower metal plate frames 50 (see Figure 3 and Figure 4 ) is provided in a manner that it can rotate around the main rotating shaft 43. The main rotating shaft 43 is provided in a manner parallel to the connecting rotating shaft 32, and the upper and lower ends of the main rotating shaft 43 are supported by a pair of upper and lower metal plate frames 50 (see Figure 4 ). On the rotating plate 42, a rod-shaped member 31A is connected (located at the first end) via a base end pin 30A on the radially outer side of the main rotating shaft 43. The details will be described later. When the rotating plate 42 rotates in the winding direction (clockwise), the three rod-shaped members 31 forming the support arm 30 are wound in the pulling direction while rotating through the connecting rotating shaft 32 (see Figure 6 and Figure 7 ), by rotating in the delivery direction (counterclockwise) which is the opposite direction to the winding direction, the three rod-shaped members 31 are pushed out in a row in the pushing direction (refer to Figure 5 ).

[0069] The rotating plate 42 has a plurality of (e.g., seven) engaging grooves 44 cut from the radially outer side to the inner side. The engaging grooves 44 are cut into a substantially U-shaped shape with a width slightly wider than the outer diameter of the connecting rotating shaft 32. The connecting rotating shaft 32 and the intermediate shaft 33 (see FIG. 3 ) of the three rod-shaped members 31 in a wound state are engaged in the seven engaging grooves 44. Figure 6 and Figure 7 Except for the engagement groove 44 that engages with the frontmost intermediate shaft 33C and the connecting rotating shafts 32A and 32B, a cutout portion 44A is formed radially outwardly of the other engagement grooves 44, which is cut obliquely counterclockwise downstream. Furthermore, the engagement groove 44 that engages with the frontmost intermediate shaft 33 is cutout in a substantially triangular shape.

[0070] like Figure 5 and Figure 7As shown, the inner surface 45 of each engagement groove 44 (except for the substantially triangular engagement groove 44 at the very front end) is formed into a generally U-shaped shape when viewed from above. Each engagement groove 44 (inner surface 45) curves clockwise from the radially inner side to the radially outer side. Specifically, in the rod-shaped member 31, the upstream connecting rotation axis 32 in the forward / retractable direction is defined as the first connecting rotation axis 32, and the downstream connecting rotation axis 32 in the forward / retractable direction is defined as the second connecting rotation axis 32. In this case, the inner surface 45 of each engagement groove 44, where the second connecting rotation axis 32 of each rod-shaped member 31 engages with the intermediate shaft 33, is formed into an arc shape centered on the first connecting rotation axis 32 of each rod-shaped member 31 or the base end pin 30A. For example, the engagement groove 44 that engages the intermediate shaft 33A of the rod-shaped member 31A and the engagement groove 44 that engages the connecting rotational shaft 32A that connects the adjacent pair of rod-shaped members 31A and 31B are formed along concentric circles centered on the base end pin 30A. Furthermore, the engagement groove 44 that engages the intermediate shaft 33B and the connecting rotational shaft 32B of the rod-shaped member 31B are formed along concentric circles centered on the connecting rotational shaft 32A. Furthermore, the engagement groove 44 that engages the intermediate shaft 33C of the rod-shaped member 31C is formed along concentric circles centered on the connecting rotational shaft 32B.

[0071] As a result, the inner surface 45 of the engagement groove 44 is formed into an arc shape along this concentric circle. In each engagement groove 44, the arc-shaped inner surface 45 on the counterclockwise downstream side is shorter than the arc-shaped inner surface 45 on the counterclockwise upstream side. Furthermore, as described above, the engagement groove 44 that engages the forward intermediate shaft 33 is formed as a substantially triangular cutout, so the arc-shaped inner surface 45 is formed only on the counterclockwise upstream side.

[0072] (Guide component)

[0073] like Figure 5 and Figure 6 As shown, the guide member 46 is made of metal, for example, and is formed into a block shape having a guide surface 46A bent along the rotating plate 42. The guide member 46 is arranged on the rear side of the rotating plate 42 (the side where the rod-shaped member 31 is pushed out to form the support arm 30), facing the rotating plate 42 from the radial outside, and is fixed to a pair of upper and lower metal plate frames 50 (see FIG. Figure 4The guide surface 46A of the guide member 46 faces the outer end surface of the rotating plate 42 at a predetermined distance from the outer end surface of the rotating plate 42. The guide member 46 is configured so that it can contact the rod-shaped members 31 when the plurality of rod-shaped members 31 in the wound state expand radially, and has the function of preventing the rod-shaped members 31 from falling off the rotating plate 42. The "predetermined distance" refers to a distance that does not hinder the rotation of the rotating plate 42 supporting the rod-shaped members 31, and that prevents the connecting rotating shaft 32 and the like from falling out of the engaging groove 44 even if the rod-shaped members 31 expand radially outward and come into contact with the guide surface 46A.

[0074] (Drive unit)

[0075] like Figure 4 As shown, the driving unit 51 is provided to drive the rotating plate 42 to rotate about the main rotating shaft 43. The driving unit 51 includes a driving motor 52, an output gear 53, and an intermediate gear 54.

[0076] The drive motor 52 is arranged on the front side of the rotating plate 42 and is fixed to the lower surface of the upper metal plate frame 50. The drive motor 52 is, for example, an electric motor such as a stepping motor that can perform positioning control. The drive motor 52 is electrically connected to the control unit 18 and is driven and controlled by the control unit 18. The output gear 53 is a spur gear, which is fixed to the main rotating shaft 43 on the upper surface of the metal plate frame 50 on the upper side and is arranged on the same axis as the rotating plate 42. The intermediate gear 54 is a so-called stepped gear, which is rotatably supported on the upper metal plate frame 50. The intermediate gear 54 meshes with the pinion 52A fixed to the output shaft of the drive motor 52 and the output gear 53. The driving force (rotational force) of the drive motor 52 rotates the output gear 53 via the intermediate gear 54, and the rotating plate 42 rotates integrally with the output gear 53.

[0077] [Function of linear motion telescopic device]

[0078] Next, refer to Figures 6 to 12 The function (action) of the linear motion expansion and contraction device 21 will be described. Figure 8 It is a perspective view showing a state where the intermediate shaft 33C at the front end is pushed out. Figure 9 It is a perspective view showing a state where the second intermediate shaft 33C is pushed out. Figure 10 It is a perspective view showing a state where the connecting rotation shaft 32B is pushed out. Figure 11 It is a perspective view showing a state where the support arm 30 is formed. Figure 12 3D is a perspective view illustrating the function of the elastic member 41 in the state where the support arm 30 is formed. In addition, for the sake of convenience, the three rod-shaped members 31 are supported on the rotating plate 42 in a wound state and the connecting rotating shaft 32 and the intermediate shaft 33 are engaged with the engaging groove 44 (see FIG. Figure 6 and Figure 7 ) is set to the initial state. In the initial state, the conveyor 25 is arranged at the storage position P1 (refer to Figure 2 ).

[0079] For example, when the output shaft (pinion 52A) of the drive motor 52 controlled by the control unit 18 rotates counterclockwise, its rotational force is transmitted to the main rotating shaft 43 via the two gears 53 and 54, and the rotating plate 42 rotates counterclockwise around the main rotating shaft 43.

[0080] like Figure 8 As shown, as the rotating plate 42 rotates counterclockwise, the intermediate shaft 33C at the front end of the rod-shaped member 31C contacts the inner surface 45 on the counterclockwise upstream side of the engagement groove 44 and is pushed out in the pushing direction (leftward) (see FIG. Figure 8 In addition, when the rotating plate 42 rotates counterclockwise, the intermediate shaft 33C pushed out in the pushing direction moves radially outward while contacting the inner surface 45 of the engaging groove 44 (see FIG. Figure 8 ), and finally disengages from the engaging groove 44.

[0081] like Figure 9 and Figure 10 As shown, when the counterclockwise rotation of the rotating plate 42 is further progressed, the second intermediate shaft 33C and the connecting rotating shaft 32B from the front end of the rod-shaped member 31C are sequentially pushed outward in the pushing direction by the same action as described above. As a result, the rod-shaped member 31C is pushed out from the rotating plate 42 in the pushing direction (see FIG. Figure 10 ).

[0082] like Figure 10 As shown, after being pushed out, rod-shaped member 31C is biased clockwise about tip pin 30B by the biasing member 40. Specifically, biasing member 40 biases rod-shaped member 31C so that it folds back relative to rod-shaped member 31B. The angle limiting portion 34 of rod-shaped member 31C abuts against the angle limiting portion 34 of rod-shaped member 31B, thereby limiting the folding of rod-shaped member 31C. This maintains rod-shaped member 31C aligned with rod-shaped member 31B in the forward and backward directions.

[0083] Subsequently, similarly to the above, as the counterclockwise rotation of the rotating plate 42 proceeds, the rod-shaped member 31B (intermediate shaft 33B, connecting rotating shaft 32A) and the rod-shaped member 31A (intermediate shaft 33A) are sequentially pushed out in the pushing direction. The control unit 18 rotates the drive motor 52 by a predetermined angle and then stops the drive motor 52.

[0084] like Figure 5 and Figure 11As shown, rod-shaped member 31B receives a force from force-applying member 40 via rod-shaped member 31C, while rod-shaped member 31A receives a force from force-applying member 40 via rod-shaped members 31B and 31C. The angle limiting portion 34 of rod-shaped member 31B abuts against the angle limiting portion 34 of rod-shaped member 31A, thereby limiting the folding of rod-shaped member 31B. Thus, the three rod-shaped members 31A, 31B, and 31C form support arm 30, which is aligned in a row in the forward and backward directions (left-right direction). Support arm 30 extends linearly in the pushing direction (leftward) from base end pin 30A fixed to rotating plate 42.

[0085] <Function of elastic components>

[0086] like Figure 3 As shown, in the state where the support arm 30 is formed, the conveyor 25 is arranged from the storage position P1 to the push-out position P2. At this time, the first guide rail 26A to the third guide rail 26C are in a state of being pulled out to the maximum extent and cannot be pulled out further. In this state, sometimes the rotating plate 42 (drive motor 52) rotates slightly counterclockwise to push the support arm 30 slightly in the push-out direction. In such a case, Figure 12 As shown, the base end pin 30A fixed to the rotating plate 42 compresses the elastic member 41 (see Figure 11 ) moves in the pushing direction along the long hole 35 (the long hole 35 on the base end side of the convex portion 36 (the contact portion 37A)). That is, the elastic member 41 elastically deforms to absorb the movement of the base end pin 30A, so that the support arm 30 does not move (refer to Figure 11 and Figure 12 ).

[0087] As described above, the support arm 30 formed by the pushed-out rod-shaped members 31A, 31B, and 31C pushes out the transport body 25 to the push-out position P2 , and the maintenance unit 23 performs maintenance on each ejection head 13A.

[0088] Furthermore, the output shaft (pinion 52A) of the drive motor 52 is rotated clockwise by the control unit 18, and the three rod-shaped members 31A, 31B, and 31C forming the support arm 30 are wound around the rotating plate 42 and return to the initial state (see FIG. Figure 6 and Figure 7 At this time, the connecting shaft 32 and the intermediate shaft 33 come into contact with the inner surface 45 on the clockwise upstream side of the engagement groove 44 and are pulled in the retraction direction (rightward). Furthermore, since the engagement groove 44 has a chamfered portion 44A, the connecting shaft 32 and the intermediate shaft 33 smoothly engage (enter) the engagement groove 44 while being guided by the chamfered portion 44A.

[0089] In the linear motion telescopic device 21 according to the embodiment described above, the support arm 30 is formed by connecting three rod-shaped members 31. Since an intermediate shaft 33 is provided in the middle of the rod-shaped members 31 in the longitudinal direction, the rod-shaped members 31 can be formed longer in the forward and backward directions, compared to, for example, the chain plates that constitute a conveyor chain. While multiple chain plates would be required to form a support arm 30 of a predetermined length, a rod-shaped member 31 having an intermediate shaft 33 can form a support arm 30 of a predetermined length with a smaller number of rod-shaped members 31. This reduces the number of connecting portions between the rod-shaped members 31, improving the positional accuracy of each rod-shaped member 31 (the tip of the support arm 30) in the forward and backward directions.

[0090] Furthermore, when the rotating plate 42 rotates counterclockwise, the connecting rotating shaft 32 and the intermediate shaft 33 come into contact with the inner surface 45 of the engaging groove 44, thereby being pushed out in the pushing direction (downstream in the forward and backward directions). As the rotating plate 42 is pushed out, the connecting shaft 32 and the intermediate shaft 33 move radially outward, thereby disengaging from the engaging groove 44. With this configuration, the rod-shaped member 31 can be smoothly pushed out by rotating the rotating plate 42.

[0091] Furthermore, according to the linear motion expansion and contraction device 21 of this embodiment, by forming the inner surface 45 of the engagement groove 44 into a predetermined arcuate shape, the connecting rotating shaft 32 and the intermediate shaft 33 can be pushed out and simultaneously moved radially outward by the rotation of the rotating plate 42. This allows each rod-shaped member 31 to be smoothly advanced and retracted.

[0092] Furthermore, according to the linear motion expansion and contraction device 21 of this embodiment, the force applying member 40 applies force to the rod-shaped members 31 to bend them in reverse, thereby maintaining the plurality of rod-shaped members 31 in a straight line. This maintains the length of the support arm 30 in the forward and backward directions substantially constant, allowing the transport body 25 (maintenance unit 23) to be positioned at a predetermined position.

[0093] Furthermore, according to the linear motion expansion and contraction device 21 according to the present embodiment, the position of the support arm 30 in the forward and backward directions can be finely adjusted by elastically deforming the elastic member 41 .

[0094] In addition, according to the linear motion expansion and contraction device 21 involved in this embodiment, for example, through the rotation of the rotating plate 42, when the multiple rod-shaped components 31 in the wound state expand radially, they will contact the guide component 46 (guide surface 46A), thereby preventing the rod-shaped components 31 from falling off the rotating plate 42.

[0095] In the linear motion expansion and contraction device 21 according to this embodiment, one or two intermediate shafts 33 are provided on each rod-shaped member 31 , but the present invention is not limited thereto.

[0096] Furthermore, in the linear motion expansion and contraction device 21 according to this embodiment, the angle limiting portions 34 of a pair of adjacent rod-shaped members 31 are brought into contact with each other by the force exerted by the force applying member 40, thereby limiting the folding of the three rod-shaped members 31. However, the present invention is not limited to this configuration. For example, the linear motion expansion and contraction device 21 may be configured such that the main rotation axis 43 is horizontal, and the rod-shaped members 31 are caused to rotate downward under their own weight, thereby causing the adjacent pair of angle limiting portions 34 to come into contact with each other (not shown). In this case, the force applying member 40 can be omitted.

[0097] In the linear motion expansion and contraction device 21 according to this embodiment, the inner surface 45 of the engagement groove 44 is formed into a predetermined arc shape, but the present invention is not limited thereto. For example, the inner surface 45 may be formed into a broken line shape (not shown).

[0098] Furthermore, while the linear motion expansion and contraction device 21 of this embodiment includes an elastic member 41 for absorbing displacement of the support arm 30 in the forward and backward directions, the present invention is not limited thereto. The elastic member 41 may be omitted if the displacement of the support arm 30 in the forward and backward directions is negligible.

[0099] In the linear motion expansion and contraction device 21 according to the present embodiment, the urging member 40 is a torsion coil spring and the elastic member 41 is a coil spring. However, an elastic body such as rubber (not shown) may be used instead of these springs.

[0100] The image forming apparatus 1 according to this embodiment is a color printer, but is not limited to this and may also be a monochrome printer, copier, facsimile machine, etc. The image forming apparatus 1 is an inkjet printer, but is not limited to this and may also be an electrophotographic image forming apparatus (printer, copier, facsimile machine, etc.).

[0101] The above-described embodiment represents only one aspect of the linear motion telescopic device, maintenance device, and image forming apparatus according to the present invention. The technical scope of the present invention is not limited to the above-described embodiment. Various changes, substitutions, and modifications may be made to the present invention without departing from the spirit of the technical concept, and the technical solution includes all possible embodiments within the scope of the technical concept.

Claims

1. A linear motion telescopic device, characterized in that: It has a rod-shaped component and a rotating plate, wherein The rod-shaped members are plural and rotatably connected via a connecting rotation axis and arranged in a row in a direction orthogonal to the connecting rotation axis to form a support arm; The rotating plate is provided in a manner capable of rotating about a main rotating shaft, and the rod-shaped member located at the first end of the supporting arm is connected to the radially outer side of the main rotating shaft via a base end pin. The rotating plate rotates in a winding direction, and the plurality of rod-shaped members are wound while rotating about the connecting rotating shaft. The rotating plate rotates in a delivery direction, which is a direction opposite to the winding direction, to push out the plurality of rod-shaped members in a row. The rod-shaped member has an intermediate shaft and an angle limiting portion, wherein The intermediate shaft is arranged in parallel with the connecting rotation shaft; The angle limiting portion abuts against the adjacent rod-shaped members in the state of forming the support arm, thereby limiting the angle between the adjacent rod-shaped members from expanding from the wound state to a predetermined angle or more. The rotating plate has a plurality of engaging grooves cut out from the outer peripheral edge toward the radial inner side, and engages with the connecting rotating shafts of the wound plurality of rod-shaped members and the intermediate shaft. When the rotary plate rotates in the delivery direction, the connecting rotary shaft and the intermediate shaft come into contact with the inner surface of the engagement groove and are pushed out of the engagement groove, thereby being disengaged from the engagement groove.

2. The linear motion telescopic device according to claim 1, characterized in that: In the rod-shaped member, when the connecting rotation axis on the side closer to the first end is set as the first connecting rotation axis, and the connecting rotation axis adjacent to the first connecting rotation axis is set as the second connecting rotation axis, the inner surface of each of the engaging grooves in which the second connecting rotation axis of each of the rod-shaped members and the intermediate shaft are engaged is formed in an arc shape centered on the first connecting rotation axis or the base end pin of each of the rod-shaped members.

3. The linear motion telescopic device according to claim 1, characterized in that: A force applying member is further provided. When the rod-shaped member located at the second end opposite to the first end of the support arm is set as the top rod-shaped member, the force applying member is arranged between the top rod-shaped member and the conveying body connected via the top pin, and applies force to the top rod-shaped member in a direction opposite to the rotation direction of the wound state.

4. The linear motion telescopic device according to claim 1, characterized in that: An elastic member is further provided between the rod-shaped member located at the first end of the support arm and the base end pin, and absorbs displacement of the support arm in the direction along the row by elastic deformation.

5. The linear motion telescopic device according to claim 1, characterized in that: A guide member is further provided, the guide member being opposed to the rotating plate from the radially outer side and being arranged so as to be contactable with the wound plurality of rod-shaped members.

6. The linear motion telescopic device according to claim 1, characterized in that: The angle restricting portion restricts the angle between the adjacent rod-shaped members so as not to expand beyond a straight line.

7. The linear motion telescopic device according to claim 1, characterized in that: The rod-shaped member located at the first end has one intermediate shaft, and the rod-shaped members other than the rod-shaped member located at the first end have two intermediate shafts.

8. The linear motion telescopic device according to claim 2, characterized in that: The inner surface includes an inner surface on the upstream side and an inner surface on the downstream side in the delivery direction, and the inner surface on the downstream side is shorter than the inner surface on the upstream side.

9. A maintenance device, characterized in that: A linear motion telescopic device according to claim 1; and The maintenance unit is moved in the row direction by the linear motion expansion and contraction device to prevent or repair clogging of a discharge head that discharges liquid from a discharge nozzle.

10. An image forming apparatus, characterized in that: A maintenance device according to claim 9 is provided.

Images