Caster device and image formation apparatus including the caster device

Abstract

To provide a caster device having a simple structure that allows height change of a housing and is attachable to and detachable from the housing.SOLUTION: A caster unit 2600, which is attachable to and detachable from an electric module bottom plate 2501, is provided with a height change shaft 2611 that comes into contact with the electric module bottom plate 2501 and moves an electric module 2500 vertically. When the caster unit 2600 is attached, the height change shaft 2611 is positioned between an upper surface of a caster base 2612 and the electric module bottom plate 2501. The height change shaft 2611 has a first outer peripheral surface and a second outer peripheral surface having different radii. A pair of caster unit guides 2505A for supporting the caster base 2612 from below are arranged on the electric module bottom plate 2501. In order to allow a user to attach and detach the caster unit 2600 to and from the electric module bottom plate 2501 without resistance, the height change shaft 2611 can be easily rotated to a state in which it does not contact the electric module bottom plate 2501.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a caster device suitable for use in an image forming apparatus such as a printer, a copier, a facsimile, or a multifunction peripheral, and to an image forming apparatus equipped with a caster device. [Background technology]

[0002] In the past, in an image forming apparatus that forms an image on a recording material, a height change mechanism has been proposed on casters arranged on a housing, and the height of the housing is changed by moving the casters up and down using the height change mechanism (Patent Document 1). In the case of a large image forming apparatus in which multiple housings are connected, by providing casters with height change mechanisms on the housings, the height of the housings can be adjusted and the housings can be connected together. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-169979 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, casters with high strength capable of withstanding the weight of the entire module, including various image formation devices and components attached to the housing, as well as exterior covers, have been used. However, depending on the type and number of devices attached to the housing, the weight of the entire module may be relatively small. Even in such cases, using high-strength casters increases costs, making it preferable to use low-strength, inexpensive casters. When low-strength, inexpensive casters are used, there is no problem even if a load is applied to the casters when the module is in a standalone state where the overall weight is small. However, if the module is connected to another housing where the overall weight of the module is large, there is a risk of the casters being damaged. Therefore, it is desirable to make casters with height-adjusting mechanisms detachable from the housing, but this creates other problems, such as the casters becoming complex and large, requiring a large installation space and increasing costs.

[0005] The present invention has been made in view of the above-mentioned problems, and aims to provide a caster device with a simple configuration that allows the height of the housing to be changed and is detachable from the housing, and an image forming apparatus equipped with the caster device. [Means for solving the problem]

[0006] A caster device according to one embodiment of the present invention is a caster device attached to a housing of an image forming apparatus, and includes: a caster for moving the housing; a base portion to which the caster is fixed on an underside; a holder portion disposed on a bottom plate of the housing and holding the base portion on an upper surface; and a shaft-shaped member disposed between the bottom plate and the base portion held on the upper surface of the holder and supported rotatably around an axial direction, wherein an outer circumferential surface of the shaft-shaped member is along a first direction intersecting the axial direction and includes a pair of first outer circumferential surfaces at both ends of a first line passing through the rotation center, and a distance from one of the pair of first outer circumferential surfaces in the first direction is a first distance, and the outer circumferential surface of the shaft-shaped member is aligned along the axial direction and a front The device includes a second pair of outer peripheral surfaces along a second direction intersecting the first direction and at a position where a second line passing through the rotation center passes, the distance from one of the pair of second outer peripheral surfaces in the second direction to the other is a second distance shorter than the first distance, in a first state where one of the pair of first outer peripheral surfaces is in contact with the bottom plate of the housing and the other of the pair of first outer peripheral surfaces is in contact with the base portion, the base portion is held so that the base portion is in contact with the upper surface of the holding portion, and in a second state where one of the pair of second outer peripheral surfaces is in contact with the bottom plate of the housing or the base portion, the base portion is movable away from the upper surface of the holding portion and is slidable in a sliding direction intersecting the vertical direction. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a caster device having a simple configuration that allows the height of the housing to be changed and that is detachable from the housing, and an image forming apparatus equipped with the caster device. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram illustrating an inkjet recording apparatus. [Figure 2] FIG. 2 is a schematic diagram showing a print module and an electrical module. [Figure 3] (a) is a perspective view showing a caster unit, (b) is a cross-sectional view showing an example of a height-adjusting shaft, and (c) is a cross-sectional view showing another example of a height-adjusting shaft. [Figure 4] FIG. 10 is a perspective view showing the electrical module bottom plate and the caster unit as viewed from the underside. [Figure 5] Schematic diagrams showing the caster unit viewed from the mounting direction, in which (a) the electrical module is connected to the print module, and (b) the electrical module is not connected to the print module. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Inkjet recording device> An embodiment of the present invention will now be described with reference to the drawings. First, an inkjet recording apparatus will be taken as an example of an image forming apparatus according to this embodiment and will be described with reference to FIGS. 1 and 2. The inkjet recording apparatus 100 shown in FIG. 1 is a so-called sheet-fed inkjet recording apparatus that forms an image on a recording material using ink and a reaction liquid based on image information input from an external device such as a computer or document reader. The recording material may be any ink-receiving material, such as paper, such as plain paper or cardboard, plastic film, such as a recording material for overhead projectors, specially shaped recording materials, such as envelopes or index paper, or cloth.

[0010] In this specification, the side on which a user stands when operating the inkjet recording apparatus 100 is referred to as the "front (or front)," and the opposite side is referred to as the "rear (or rear)." Furthermore, the left side when viewed from the front is referred to as the "left," and the right side when viewed from the front is referred to as the "right." Figure 1 shows the inkjet recording apparatus 100 as viewed from the front.

[0011] 1, the inkjet recording apparatus 100 includes a feeding module 1000, a print module 2000, a drying module 3000, a fixing module 4000, a cooling module 5000, an inverting module 6000, and a stacking module 7000. These modules are connected so that the recording material S can be transferred between adjacent modules, and the recording material S supplied from the feeding module 1000 undergoes various processes as it is transported along a transport path within each module, and is finally discharged to the stacking module 7000. Note that although some modules are not directly involved in image formation, each module is a part of the image forming apparatus.

[0012] A housing 1010 of the feeding module 1000 is provided with casters for moving the feeding module 1000. The feeding module 1000 is provided with cassettes 1500a, 1500b, and 1500c for storing recording materials S, and the cassettes 1500a to 1500c are provided so as to be able to be pulled out toward the front side to store the recording materials S. The recording materials S are fed one by one in each of the cassettes 1500a to 1500c by a separation belt and a conveying roller, and are conveyed to the print module 2000. The number of cassettes 1500a to 1500c is not limited to three, and a configuration having one, two, four or more cassettes is also possible.

[0013] A housing 2010 of the print module 2000 is provided with casters for moving the print module 2000. The print module 2000 has a pre-imaging transport unit (not shown), a print belt unit 2200, and a recording unit 2300 as image forming units that form an image on the recording material S, and these image forming units are supported by the housing 2010. The recording material S transported from the feeding module 1000 is transported to the print belt unit 2200 after the pre-imaging transport unit corrects the inclination and position of the recording material S. The recording unit 2300 is disposed at a position facing the print belt unit 2200 with respect to the transport path of the recording material S. The recording unit 2300 as an image forming unit forms an image by ejecting ink onto the recording material S from above using multiple recording heads as the recording material S is transported by the print belt unit 2200. The recording material S is transported by suction, ensuring clearance between the recording material S and the recording heads. In this embodiment, a total of five line-type recording heads corresponding to four colors, Y (yellow), M (magenta), C (cyan), and Bk (black), and the reaction liquid are arranged in the transport direction.

[0014] The number of ink colors and recording heads is not limited to five. The inkjet method for ejecting ink can be a method using a heat generating element, a method using a piezoelectric element, a method using an electrostatic element, a method using a MEMS element, or the like. Each color of ink is supplied to the recording head from an ink tank (not shown) via an ink tube.

[0015] The recording material S on which an image has been formed in the recording section 2300 is conveyed by the print belt unit 2200 to an inline scanner (not shown), which reads the image formed on the recording material S. Here, the misalignment and color density of the image formed on the recording material S are detected, and based on this image misalignment and color density, the image to be formed on the recording material S, its density, etc. are corrected.

[0016] The print module 2000 is provided with an operation unit 200. For example, the operation unit 200 has a liquid crystal display unit 210 capable of displaying various information, and various displays such as various programs and data, or the completion of an image formation job or the occurrence of an error, can be displayed on the liquid crystal display unit 210. The operation unit 200 may be, for example, a touch panel capable of receiving inputs for starting various programs such as an image formation job and inputting various data in response to touch operations by the user. Note that the above-mentioned inputs for starting various programs and inputting various data may be input not only from the operation unit 200 but also from an external device such as a computer.

[0017] A housing 3010 of the drying module 3000 is provided with casters for moving the drying module 3000. The drying module 3000 has an outside air blowing unit 3100, a decoupling section 3200, a drying belt unit 3300, and a warm air blowing unit 3400. The drying module 3000 reduces the liquid content of the ink applied to the recording material S in order to improve the fixation of the ink to the recording material S by the subsequent fixing module 4000.

[0018] The recording material S on which the image has been formed is transported to a decoupling section 3200 arranged in the drying module 3000. In the decoupling section 3200, a frictional force is generated between the recording material S and the belt by the wind pressure of air blown from an outside air blowing unit 3100 arranged above the decoupling section 3200, causing the belt to transport the recording material S. In this way, the recording material S placed on the belt is transported by frictional force, thereby preventing the recording material S from shifting as it is transported between the print belt unit 2200 and the decoupling section 3200.

[0019] The recording material S conveyed from the decoupling section 3200 is attracted and conveyed by the drying belt unit 3300. A warm air blowing unit 3400 is disposed above the drying belt unit 3300, and hot air heated by a heater is blown from the warm air blowing unit 3400 onto the recording material S conveyed by the drying belt unit 3300. This dries the ink applied to the recording material S.

[0020] A housing 4010 of the fixing module 4000 is provided with casters for moving the fixing module 4000. The fixing module 4000 has a fixing belt unit 4100. The fixing belt unit 4100 fixes ink to the recording material S by passing the recording material S conveyed from the drying module 3000 between a heated upper belt unit and a lower belt unit.

[0021] A housing 5010 of the cooling module 5000 is provided with casters for moving the cooling module 5000. The cooling module 5000 has a plurality of cooling sections 5001, which cool the high-temperature recording material S transported from the fixing module 4000. Although not shown, the cooling sections 5001 use a fan to draw air (outside air) from outside the housing 5010 into a cooling box to increase the pressure inside the cooling box, and the air sprayed from the cooling box through a nozzle due to the pressure hits the recording material S to cool the recording material S. The cooling sections 5001 are arranged on both sides of the transport path of the recording material S and cool both sides of the recording material S.

[0022] The cooling module 5000 is also provided with a conveying path switching unit 5002. The conveying path switching unit 5002 switches the conveying path of the recording material S depending on whether the recording material S is conveyed to the reversing module 6000 or conveyed to a double-sided conveying path for double-sided printing, in which images are formed on both sides of the recording material S.

[0023] A housing 6010 of the reversing module 6000 is provided with casters for moving the reversing module 6000. Furthermore, a housing 7010 of the stacking module 7000 is provided with casters for moving the stacking module 7000. The reversing module 6000 has a reversing section 6400. The reversing section 6400 reverses the recording material S being conveyed, changing the front and back orientation of the recording material S when it is discharged to the stacking module 7000. The stacking module 7000 has a top tray 7200 and a stacking section 7500, and stacks the recording material S conveyed from the reversing module 6000.

[0024] During double-sided printing, the recording material S is conveyed to a conveyance path below the cooling module 5000 by the conveyance path switching unit 5002. The recording material S then passes through a double-sided conveyance path including the fixing module 4000, drying module 3000, print module 2000, and feeding module 1000, before being returned to the print module 2000. The double-sided conveyance section of the fixing module 4000 is provided with an inverting unit 4200 that inverts the recording material S. After the recording material S is returned to the print module 2000, an image is formed on the other side with ink, and the recording material S passes through the drying module 3000, fixing module 4000, cooling module 5000, and inverting module 6000 before being ejected to the stacking module 7000. The stacking module 7000 has a top tray 7200 and a stacking unit 7500, and is used to stack the recording material S conveyed from the inverting module 6000.

[0025] <Electrical module> 2, in this embodiment, an electrical module 2500 is connected to the rear surface of a housing 2010 (second housing) of the print module 2000. The housing 2510 (first housing) of the electrical module 2500 is composed of an electrical module bottom plate 2501, electrical module columns 2502, and an electrical module top plate 2503. Although not shown in FIG. 2, an exterior cover is attached to the housing 2510.

[0026] A plurality of electrical module columns 2502 are arranged in the left-right direction and extend upward from the electrical module bottom plate 2501. An electrical module top plate 2503 is connected to the plurality of electrical module columns 2502 on the opposite side of the electrical module bottom plate 2501. An electrical unit 2700 is fixed to the electrical module columns 2502. In the example shown in FIG. 2, the electrical unit 2700 is fixed to two electrical module columns 2502, one located at the left end and one located toward the center of the electrical module bottom plate 2501. In this way, the electrical unit 2700 is supported by the housing 2510 of the electrical module 2500.

[0027] In the inkjet recording apparatus 100, user operation systems such as the operation unit 200 (see FIG. 1) are all located on the front side, eliminating the need for a user to go around to the rear of the inkjet recording apparatus 100 to remove paper from the rear side when a paper jam occurs. On the other hand, because the user operation systems are all located on the front side, the drive system that applies drive force to each component of the apparatus and the electrical system that performs electrical control are all located on the rear side. The electrical system here includes electrical boards that perform electrical control, such as high-voltage boards, control boards, drive boards, and communication boards, as well as bundled cables that electrically connect these boards. The electrical boards are boards on which, for example, a CPU, memory, electronic components, electrical components, connectors, etc. are mounted. The electrical unit 2700 holds these electrical boards and bundled cables.

[0028] The weight of the electrical unit 2700 is smaller than, for example, the print belt unit 2200 and the recording unit 2300 of the print module 2000. Therefore, the weight of the entire electrical module 2500, including the housing 2510 and the electrical unit 2700, is smaller than the weight of the entire print module 2000, including the housing 2010, the print belt unit 2200, and the recording unit 2300.

[0029] Furthermore, two electrical module posts 2502 disposed on both the left and right ends of the electrical module bottom plate 2501 are provided with electrical module hooks 2504 that protrude toward the print module 2000. The electrical module hooks 2504, which serve as locking portions, enter and become hooked into hook hook grooves (not shown) provided in the print module 2000, thereby locking the electrical module 2500 to the print module 2000. With the electrical module 2500 hanging from the print module 2000 via the electrical module hooks 2504, the electrical module 2500 is fixed to the print module 2000 with fixing screws (not shown). In this manner, the electrical module 2500 is connected to the print module 2000. The amount by which the electrical module hooks 2504 engage the hook hook grooves is, for example, 3 mm. In this case, the user can insert the electrical module hook 2504 into the hook groove, and then move the electrical module 2500 from top to bottom relative to the print module 2000 by 3 mm or more to hook the electrical module hook 2504 into the hook groove.

[0030] The print module 2000 has casters 2050 arranged at the four corners of the bottom surface of the housing 2010 to enable movement of the print module 2000. Furthermore, near the casters 2050 arranged at the four corners, an installation mechanism 2051 is provided to lift the housing 2010 upward to a position where the casters 2050 do not come into contact with the installation surface when installing the print module 2000. The installation mechanism 2051 raises the casters 2050 so that they do not come into contact with the installation surface, thereby preventing the print module 2000 from moving unintentionally after installation by the user. The installation mechanism 2051 may be provided in the feed module 1000, drying module 3000, fixing module 4000, cooling module 5000, reversing module 6000, and stacking module 7000 in addition to the print module 2000.

[0031] In the electrical module 2500, caster units 2600 are disposed on the bottom surface of the housing 2510 so that the electrical module 2500 can be moved independently. Specifically, the caster units 2600 are detachably attached to the electrical module bottom plate 2501. Furthermore, the caster units 2600 have a function of moving the electrical module 2500 and a function of changing the height of the housing 2510 by moving the housing 2510 in the vertical direction, in addition to a function of moving the electrical module 2500. Note that, although one caster unit 2600 is disposed on each of the left and right ends of the electrical module bottom plate 2501 here, this is not limiting. For example, three or more caster units 2600 may be disposed on the bottom surface of the housing 2510.

[0032] <Caster unit> The above-described caster unit 2600 will be described with reference to FIGS. 3(a) to 5(b). As shown in FIG. 3(a), the caster unit 2600 of this embodiment includes a caster 2613, a caster base 2612 as a base portion to which the caster 2613 is attached, and a height adjustment shaft 2611. One or more freely swivelable casters 2613 are fixed to the underside of the caster base 2612. Here, two casters 2613 are arranged on one caster base 2612 side by side in the mounting direction of the caster unit 2600 to the housing 2510 (the direction of arrow V). This is not a limitation, and one or more casters 2613 may be arranged on one caster base 2612. However, from the viewpoint of stability of the electrical module 2500, it is preferable that the caster unit 2600 be configured so that at least four casters 2613 are arranged at the four corners of the electrical module bottom plate 2501.

[0033] <Height change axis> A height adjustment shaft 2611, which is elongated in the mounting direction (sliding direction) that intersects the vertical direction, is disposed on the upper surface of the caster base 2612 opposite the lower surface. More specifically, the height adjustment shaft 2611 is disposed between the electrical module bottom plate 2501 and the caster base 2612, which is held on the upper surface of the lower tip portion 25051 of the caster unit guides (2505A, 2505B) described below, and is supported so as to be rotatable around the axial direction (see FIG. 4). When the caster unit 2600 is mounted in the housing 2510, the height adjustment shaft 2611 is located between the upper surface of the caster base 2612 and the electrical module bottom plate 2501.

[0034] The height adjustment shaft 2611, which serves as a shaft-shaped member, is rotatably supported by a height adjustment shaft support portion 2614 of the caster base 2612. The height adjustment shaft support portion 2614 is formed, for example, by bending upward the upstream end portion of the caster base 2612 in the installation direction of the caster unit 2600. A through-hole 2614a is formed in this height adjustment shaft support portion 2614, and the shaft portion of the height adjustment shaft 2611 passes through the through-hole 2614a and is supported by the height adjustment shaft support portion 2614. A user can rotate the height adjustment shaft 2611 by using the portion of the height adjustment shaft 2611 that protrudes from the through-hole 2614a toward the upstream side in the installation direction.

[0035] As shown in Fig. 3(b), the height-changing shaft 2611 has a first outer peripheral surface 2611a and a second outer peripheral surface 2611b with different radii. That is, the outer peripheral surface of the height-changing shaft 2611 includes a pair of first outer peripheral surfaces 2611a at both ends of a first line along a first direction intersecting the axial direction and passing through the rotation center, and a pair of second outer peripheral surfaces 2611b at positions where a second line along a second direction intersecting the axial direction and the first direction and passing through the rotation center passes. Also, the outer peripheral surface of the height-changing shaft 2611 includes a circular portion that is circular in a cross-section intersecting the axial direction, and a first linear portion corresponding to an arc of the circle. Both pairs of the first outer peripheral surfaces 2611a are included in the circular portion, one of the pair of the second outer peripheral surfaces 2611b is included in the circular portion, and the other of the pair of the second outer peripheral surfaces 2611b is included in the first linear portion. In the present embodiment, the contact position between the height-changing shaft 2611 and the electrical equipment module bottom plate 2501 shifts between the first outer peripheral surface 2611a and the second outer peripheral surface 2611b due to rotation. Accordingly, since the housing 2510 is moved in the vertical direction, the distance between the electrical equipment module bottom plate 2501 and the caster pedestal 2612 can be changed.

[0036] In the present embodiment, the distance from one to the other of the pair of the first outer peripheral surfaces 2611a in the first direction is a first distance (R), and the distance from one to the other of the pair of the second outer peripheral surfaces 2611b in the second direction is a second distance (r) shorter than the first distance. In other words, the second outer peripheral surface 2611b has a smaller radius than the first outer peripheral surface 2611a (r < R). For example, the height-changing shaft 2611 is a D-cut shaft having a cross-sectional D shape with a diameter of "13 mm", and the second outer peripheral surface 2611b is formed on the D-cut surface at a position where it enters the rotation center side by a length of "5.5 mm" from the original outer periphery (shown by a dotted line). Note that the height-changing shaft 2611 is not limited to the D-cut shaft, and may be a two-sided cut-shaped shaft in which the second outer peripheral surface 2611b is formed on a two-sided cut surface as shown in Fig. 3(c). In this case, the outer peripheral surface of the height-changing shaft 2611 includes a circular portion that is circular in a cross-section intersecting the axial direction, and a first linear portion and a second linear portion corresponding to an arc of the circle. Both pairs of the first outer peripheral surfaces 2611a are included in the circular portion, one of the pair of the second outer peripheral surfaces 2611b is included in the first linear portion, and the other of the pair of the second outer peripheral surfaces 2611b is included in the second linear portion.

[0037] 4, the electrical module bottom plate 2501 has a pair of caster unit guides 2505A, 2505B arranged side by side as retainers on the upstream and downstream sides of the installation direction of the caster unit 2600. Each of the caster unit guides (2505A, 2505B) protrudes downward from the electrical module bottom plate 2501, with a lower tip 25051 bent inward so that the upper surface of the lower tip 25051 supports the caster base 2612 from below in a slidable manner. In this embodiment, the caster unit guides 2505A, 2505B and the caster unit 2600 each constitute a part of the caster device.

[0038] The caster unit 2600 is inserted in this order from the pair of caster unit guides 2505A on the rear side (upstream side in the installation direction) to the pair of caster unit guides 2505B on the front side (downstream side in the installation direction), and is installed on the electrical module bottom plate 2501. At this time, the caster pedestal 2612 slides between the lower tip 25051 and the electrical module bottom plate 2501 and is held between the lower tip 25051 and the electrical module bottom plate 2501 so as to be able to fit loosely in the up-and-down direction. In addition, the pair of caster unit guides 2505A, 2505B are arranged opposite each other in the left-right direction, and the distance between one and the other is approximately the same as the left-right width of the caster pedestal 2612, thereby restricting left-right movement of the caster pedestal 2612.

[0039] The changeable shaft support portion 2614 of the caster base 2612 abuts from the outside against an abutment portion 2501a formed on the upstream side in the installation direction of the electrical module bottom plate 2501, thereby restricting movement of the caster unit 2600 in the installation direction. The abutment portion 2501a is formed, for example, by bending the upstream end of the electrical module bottom plate 2501 in the installation direction upward.

[0040] As a result, in a first state in which one of the pair of first outer peripheral surfaces 2611a of the height adjustment shaft 2611 is in contact with the electrical module bottom plate 2501 and the other of the pair of first outer peripheral surfaces 2611a is in contact with the caster base 2612, the caster base 2612 is held so as to be in contact with the upper surfaces of the lower tip portions 25051 of the caster unit guides 2505A and 2505B. On the other hand, in a second state in which one of the pair of second outer peripheral surfaces 2611b of the height adjustment shaft 2611 is in contact with the electrical module bottom plate 2501 or the caster base 2612, the caster base 2612 is able to move away from the upper surfaces of the lower tip portions 25051 of the caster unit guides 2505A and 2505B and is able to slide in a sliding direction that intersects the up-and-down direction.

[0041] The user can move the electrical module 2500 with the caster units 2600 attached by itself. When connecting the electrical module 2500 to the print module 2000, the user moves the electrical module 2500 with the caster units 2600 attached to a position adjacent to the rear of the print module 2000. Thereafter, as described above, the electrical module 2500 is connected to the print module 2000 while hanging from the print module 2000 by the electrical module hooks 2504 (see FIG. 2). Then, when the electrical module 2500 is hanging from the print module 2000, the user can easily attach and detach the caster units 2600 to and from the electrical module bottom plate 2501. This will be described below with reference to FIGS. 5(a) and 5(b). 5A shows a state in which the electrical module 2500 is connected to the print module 2000, and FIG. 5B shows a state in which the electrical module 2500 is not connected to the print module 2000.

[0042] In this embodiment, the height H from the floor F (installation surface) to the electrical module bottom plate 2501 shown in FIG. 5A is, for example, 75 mm. When the electrical module 2500 is connected to the print module 2000, the D-cut surface (second outer peripheral surface 2611b, see FIG. 3B) of the height adjustment shaft 2611 faces the upper electrical module bottom plate 2501, and the distance h from the floor F (installation surface) to the D-cut surface is 74.5 mm. Therefore, when the electrical module 2500 is suspended from the print module 2000, the user rotates the height adjustment shaft 2611 so that the D-cut surface faces the electrical module bottom plate 2501. In this manner, the caster unit guides 2505A and 2505B can hold the caster base 2612 without the height adjustment shaft 2611 coming into contact with the electrical module bottom plate 2501. Since the height adjustment shaft 2611 is not in contact with the electrical module bottom plate 2501, the user can attach and detach the caster unit 2600 to and from the electrical module bottom plate 2501 without resistance.

[0043] To remove the electrical module 2500 from the print module 2000, the user removes the fixing screws that secure the electrical module 2500 to the print module 2000 and then releases the electrical module hook 2504 from its engagement with the print module 2000. The user rotates the height adjustment shaft 2611 from the state shown in FIG. 5(a) until the angle at which the vertical length of the height adjustment shaft 2611 becomes equal to its diameter, as shown in FIG. 5(b). This causes the distance h' from the vertical upper surface of the height adjustment shaft 2611 to the floor F (installation surface) to become 80 mm, and the caster unit 2600 lifts the electrical module 2500. The lift amount "h'-H" at this time is 5 mm, which is larger than the 3 mm of engagement amount of the electrical module hook 2504. Therefore, a separate lifting operation to release the engagement of the electrical module hook 2504 is not required. In this way, when one of the pair of first outer peripheral surfaces 2611a of the height adjustment shaft 2611 is in contact with the electrical module bottom plate 2501, the other of the pair of first outer peripheral surfaces 2611a is in contact with the caster base 2612, and the caster base 2612 is in contact with the upper surface of the lower tip 25051 of the caster unit guide (2505A, 2505B), the engagement between the electrical module 2500 and the print module 2000 is released.

[0044] The user can connect the electrical module 2500 to the print module 2000 by reversing the above steps. After connecting the electrical module 2500 to the print module 2000, the user rotates the height adjustment shaft 2611 from the state shown in FIG. 5(b) to an angle where the D-cut surface of the height adjustment shaft 2611 faces the electrical module bottom plate 2501, as shown in FIG. 5(a). As described above, in this state, the height adjustment shaft 2611 is not in contact with the electrical module bottom plate 2501. Therefore, the user can easily remove the caster unit 2600 from the caster unit guide 2505A. Therefore, the caster 2613 is not subjected to the load of the print module 2000, which is heavier than the electrical module 2500. This means that the load-bearing capacity of the caster 2613 of the caster unit 2600 only needs to be considered based on the load of the electrical module 2500, allowing the use of small, inexpensive casters 2613.

[0045] As described above, in this embodiment, the height adjustment shaft 2611, which comes into contact with the electrical module bottom plate 2501 and moves the electrical module 2500 up and down, is rotatably provided on the caster unit 2600 that is detachable from the electrical module bottom plate 2501. To enable the user to attach or detach the caster unit 2600 to or from the electrical module bottom plate 2501 without resistance, the user can easily rotate the height adjustment shaft 2611 to a state where it is not in contact with the electrical module bottom plate 2501. The caster unit 2600 having such a height adjustment shaft 2611 has a simple configuration and can be easily made compact, so it does not require a large installation space and costs can be reduced. [Explanation of symbols]

[0046] 100...image forming apparatus (inkjet recording apparatus), 2010...second housing (housing), 2200...image forming unit (print belt unit), 2300...image forming unit (recording unit), 2501...bottom plate (electrical module bottom plate), 2504...engaging portion (electrical module hook), 2505A, 2505B...caster device (holding portion, caster unit guide), 2510...housing (first housing), 2600...caster device (caster unit), 2611...shaft-shaped member (height-adjusting shaft), 2611a...first outer peripheral surface, 2611b...second outer peripheral surface, 2612...base portion (caster base), 2613...caster, 2700...electrical unit, S...recording material

Claims

1. A caster device attached to a housing of an image forming apparatus, Casters for moving the housing; a base portion having the casters fixed to its underside; a holding portion disposed on a bottom plate of the housing and configured to hold the base portion on an upper surface thereof; a shaft-shaped member disposed between the bottom plate and the base portion held on the upper surface of the holding portion, and supported rotatably around an axial direction, the outer peripheral surface of the shaft-shaped member includes a pair of first outer peripheral surfaces at both ends of a first line that is along a first direction intersecting the axial direction and that passes through the rotation center, a first distance is a distance from one of the pair of first outer peripheral surfaces to the other in the first direction; the outer circumferential surface of the shaft-shaped member includes a pair of second outer circumferential surfaces along a second direction intersecting the axial direction and the first direction and at a position on a second line passing through the rotation center, a distance from one of the pair of second outer peripheral surfaces in the second direction to the other of the pair of second outer peripheral surfaces is a second distance shorter than the first distance, In a first state in which one of the pair of first outer peripheral surfaces is in contact with the bottom plate of the housing and the other of the pair of first outer peripheral surfaces is in contact with the pedestal portion, the pedestal portion is held so that the pedestal portion is in contact with the upper surface of the holding portion, In a second state in which one of the pair of second outer peripheral surfaces is in contact with the bottom plate of the housing or the base portion, the base portion is separable from the upper surface of the holding portion, and the base portion is slidable in a sliding direction intersecting the up-down direction. A caster device characterized by:

2. the outer circumferential surface of the shaft-shaped member includes a circular portion that is circular in a cross section intersecting the axial direction, and a first straight line portion that corresponds to an arc of the circle, The pair of first outer peripheral surfaces are both included in the circular portion, one of the pair of second outer peripheral surfaces is included in the circular portion, and the other of the pair of second outer peripheral surfaces is included in the first linear portion; The caster device according to claim 1 .

3. the outer circumferential surface of the shaft-shaped member includes a circular portion that is circular in a cross section intersecting the axial direction, and a first straight line portion and a second straight line portion that respectively correspond to the circular arc, The pair of first outer peripheral surfaces are both included in the circular portion, one of the pair of second outer peripheral surfaces is included in the first linear portion, and the other of the pair of second outer peripheral surfaces is included in the second linear portion; The caster device according to claim 2 .

4. A plurality of the casters are fixed to the base portion in a line in the sliding direction. The caster device according to claim 1 .

5. An image forming apparatus for forming an image on a recording material, a first housing; a second housing disposed adjacent to the first housing; The caster device according to any one of claims 1 to 4, attached to the first housing; a locking portion for locking the first housing to the second housing, When the first housing is locked to the second housing, the base is slidable in the sliding direction. An image forming apparatus characterized by:

6. the first housing and the second housing are released from engagement with each other when one of the pair of first outer peripheral surfaces is in contact with the bottom plate of the first housing, the other of the pair of first outer peripheral surfaces is in contact with the base portion, and the base portion is in contact with the upper surface of the holding portion.

6. The image forming apparatus according to claim 5,

7. the holding portion is capable of holding the base portion without causing the pair of first outer peripheral surfaces and the pair of second outer peripheral surfaces of the shaft-shaped member to come into contact with the bottom plate when the first housing is locked to the second housing by the locking portion.

6. The image forming apparatus according to claim 5,

8. an image forming unit that forms an image on a recording material; an electrical unit having a board for controlling the image forming unit; The electrical unit is supported by the first housing. the image forming unit is supported by the second housing; 6. The image forming apparatus according to claim 5,

Images