Assist device

Abstract

To ensure that the transport of rolling carts can be carried out properly. [Solution] An assist device used for transporting a wheeled cart, comprising: a main body inserted from one side of the cart into the gap formed between the wheel and the ground surface; a drive wheel driven by a drive source; an auxiliary wheel fixed to the main body and having a smaller diameter than the drive wheel; and a displacement mechanism that displaces the drive wheel and the main body relative to each other in the vertical direction with respect to the ground surface, wherein the displacement mechanism displaces the drive wheel between a self-supporting position in which the drive wheel and the auxiliary wheel are in contact with the ground surface and a transport position in which the drive wheel is in contact with the ground surface and the auxiliary wheel is lifted off the ground surface.

Description

Technical Field

[0001] The present invention relates to an assist device.

Background Art

[0002] Patent Document 1 discloses a lifting transporter that assists the movement of a basket cart for carrying luggage.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

[0004] The lifting transporter of this Patent Document 1 has a engaging body that engages with the lower part of one side of the basket cart, a lifting mechanism that raises and lowers the engaging body, and drive wheels. The basket cart has free wheels at its four corners. The lifting transporter floats a pair of free wheels on one side of the basket cart by the lifting mechanism, and after grounding only the pair of free wheels on the other side, transports the basket cart with one side floating by the driving force of the drive wheels.

[0005] In the lifting transporter, a pair of free wheels (auxiliary wheels) for preventing the tipping of the lifting transporter are provided on both sides of the drive wheels. The pair of free wheels are grounded together with the drive wheels while the drive wheels are transporting the basket cart.

Problems to be Solved by the Invention

[0006] Since the free wheels for preventing tipping are for the purpose of preventing tipping, there is no need to use large-diameter wheels. Therefore, free wheels with a smaller diameter than the drive wheels are adopted, and the entire device is designed to be compact. Here, when transporting the basket cart, in the lifting transporter, the free wheels also rotate in a grounded state together with the drive wheels.

[0007] However, depending on the environment in which the cage cart is used, small steps or grooves may be present along the transport route. For example, if a small-diameter free wheel gets stuck in a groove or cannot overcome a step, it will hinder the transport of the cage cart by the lifting and transporting equipment. To avoid such situations, it is conceivable to increase the diameter of the free wheel, but depending on the placement of the enlarged free wheel on the cage cart, it may interfere with the drive wheel.

[0008] Therefore, there is a need to use a device equipped with auxiliary wheels that are smaller in diameter than the drive wheels to enable proper transport of the cart. [Means for solving the problem]

[0009] One aspect of the present invention is An assist device used for transporting wheeled carts, The main body portion is inserted from one side of the cart into the gap formed between the wheel and the ground surface, Driven wheels driven by a power source, Auxiliary wheels, which are fixed to the main body and have a smaller diameter than the drive wheels, It has a displacement mechanism that causes relative displacement between the drive wheel and the main body in the vertical direction with respect to the ground surface, The displacement mechanism is an assist device that displaces the main body between a self-supporting position in which the drive wheel and the auxiliary wheel are in contact with the ground surface, and a transport position in which the drive wheel is in contact with the ground surface and the auxiliary wheel is lifted off the ground surface. [Effects of the Invention]

[0010] According to one aspect of the present invention, the transport of the cart can be carried out appropriately. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a diagram illustrating a trolley and an assist device. [Figure 2] Figure 2 is a diagram illustrating the assist device. [Figure 3]FIG. 3 is a diagram for explaining the assist device. [Figure 4] FIG. 4 is a diagram for explaining the assist device. [Figure 5] FIG. 5 is a diagram for explaining the assist device. [Figure 6] FIG. 6 is a diagram for explaining the assist device. [Figure 7] FIG. 7 is a diagram for explaining around the gripping part of the assist device. [Figure 8] FIG. 8 is a diagram for explaining around the gripping part of the assist device. [Figure 9] FIG. 9 is a diagram for explaining the displacement mechanism and the link mechanism. [Figure 10] FIG. 10 is a diagram for explaining the displacement mechanism and the link mechanism. [Figure 11] FIG. 11 is a diagram for explaining the operations of the displacement mechanism and the link mechanism and the conveyance of the cage car. [Figure 12] FIG. 12 is a diagram for explaining the engagement / disengagement mechanism. [Figure 13] FIG. 13 is a diagram for explaining the engagement / disengagement mechanism. [Figure 14] FIG. 14 is a diagram for explaining the assist device according to a modification. [Figure 15] FIG. 15 is a diagram for explaining the assist device according to another embodiment. [Figure 16] FIG. 16 is a diagram for explaining the assist device according to another embodiment. [Figure 17] FIG. 17 is a diagram for explaining the assist device according to another embodiment. [Figure 18] FIG. 18 is a diagram for explaining the assist device according to another embodiment. [Figure 19] FIG. 19 is a diagram for explaining the assist device according to another embodiment. [Figure 20] FIG. 20 is a diagram for explaining the assist device according to another embodiment.

Mode for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described using the example of an assist device 2 used for transporting a cart 1 loaded with workpieces such as parts. Figure 1 is a diagram illustrating the cart 1 and the assist device 2. Figures 2 to 6 are diagrams illustrating the assist device 2. Figure 2 shows an enlarged perspective view of only the main body 20 side of the assist device 2. Figure 3 shows a view of the assist device 2 from the direction of arrow AA in Figure 1. Figure 4 shows an enlarged view of region E in Figure 3. Figure 5 schematically shows a front view of the assist device 2 cut along line BB in Figure 1. Figure 6 schematically shows a cross-section of the assist device 2 cut along line AA in Figure 3.

[0013] In the following explanation, the symbols X, Y, and Z in Figure 1, along with the terms "upper" and "lower," may be used to describe the positional relationships of the components of the cart 1 and the assist device 2. "X direction" refers to the width direction of the assist device 2. "Y direction" refers to the insertion direction of the main body 20 of the assist device 2 into the cart 1. "Z direction" refers to the vertical direction relative to the ground contact surface FR of the assist device 2. "Upper side" and "lower side" refer to the upper and lower sides in the vertical direction relative to the ground contact surface FR.

[0014] [Cage cart] The cage cart 1 is a trolley with wheels. In the cage cart 1, a grid-like fence 11 is installed along the outer circumference of the rectangular bottom wall 10. The cage cart 1 is surrounded by the fence 11 on at least three sides. On the underside of the bottom wall 10, free wheels 12 are provided at the four corners. In the cage cart 1, there is a gap S between the bottom wall 10 and the ground surface FR that corresponds to the height of the free wheels 12.

[0015] The cart 1, equipped with free-rotating wheels 12 at each of its four corners, can change direction to any desired direction because the rotation direction of each free-rotating wheel 12 can be freely switched. However, the rotation direction may suddenly change due to the influence of the condition of the ground surface FR while the cart 1 is being moved, which presents challenges to its ability to travel in a straight line.

[0016] [Assist device] The assist device 2 lifts one side of the cart 1 by inserting its main body 20 into the gap S, leaving only the pair of free wheels 12, 12 on the other side in contact with the ground. The cart 1 is then moved by the driving force of the drive wheels W, W provided by the assist device 2. In the case of cart 1, only the pair of free wheels 12, 12 on the other side are in contact with the ground, so cart 1 can be transported more stably than when all four free wheels 12, 12, 12, 12 are in contact with the ground.

[0017] As shown in Figure 2, the main body 20 of the assist device 2 is formed in a substantially rectangular shape from a pair of side frames 21, 21 arranged parallel to each other with a gap between them, and a pair of reinforcing frames 22, 23 connecting the ends of the pair of side frames 21, 21. Between the reinforcing frames 22 and 23, a fixing frame 48 is provided at a position closer to the reinforcing frame 22 on the front end 20a side. One end and the other end of the fixing frame 48 in the longitudinal direction are fixed to the side frames 21, 21, respectively.

[0018] As shown in Figure 1, the main body portion 20 is the part that is inserted into the gap S between the trolley 1 and the ground surface FR. The upper surface 20c of the main body portion 20 is the contact surface that comes into contact with the bottom wall portion 10 of the trolley 1 when the trolley 1 is tilted. As shown in Figure 6, a plate member 25 is provided at the base end 20b on the reinforcing frame 23 side of the main body 20. As shown in Figure 5, the plate member 25 is provided along the entire length of the main body 20 in the width direction (X direction: left and right direction in the figure). The side edges 25a and 25b of the plate member 25 are flush with the side edges 20e and 20f of the main body 20 in the width direction (X direction).

[0019] As shown in Figure 6, a support column 27 is provided on the side of the plate member 25 opposite to the main body 20 (right side in the figure). As shown in Figure 5, when viewed from the Z direction, the support columns 27 are provided at positions that overlap one side frame 21 (left side in the figure) and the other side frame 21 (right side in the figure) in the X direction. The assist device 2 is equipped with a pair of support columns 27, 27 on both sides of the plate member 25 in the X direction.

[0020] Figures 7 and 8 illustrate the area around the gripping portion 30 (first gripping portion 31, second gripping portion 32) of the assist device 2. In Figure 7, the area on the upper end side of the support column 27 is schematically shown in an enlarged view when the assist device 2 is viewed from the X direction. In Figure 8, a schematic cross-section along line AA in Figure 7 is shown. In Figure 8, the area of ​​the gripping portion 30 is shown in cross-section, and a part of the area of ​​the cart 1 is shown by dashed lines. Note that the housing portion 28 (see Figure 1) is not shown in Figure 8.

[0021] As shown in Figure 1, the upper ends of the support columns 27, 27 are provided with a housing section 28 for housing the control board and battery of the assist device 2, and a gripping section 30 for the operator to hold when operating the assist device 2. The housing section 28 is provided sandwiched between the support columns 27, 27.

[0022] As shown in Figure 8, reinforcing beams 29 are provided at the upper ends of the support columns 27, 27. The reinforcing beams 29 connect the upper ends of the support columns 27, 27. The reinforcing beams 29 are oriented along the X direction. On the reinforcing beams 29, a gripping portion 30 is provided on the side opposite to the cart 1 in the Y direction (left-right direction in the figure) (right side in the figure).

[0023] The gripping portion 30 comprises a first gripping portion 31, a second gripping portion 32, and a support cylinder 33. Viewed from the Z direction, the first gripping portion 31, the second gripping portion 32, and the support cylinder 33 are concentrically arranged on a common axis X30. The axis X30 is a straight line parallel to the ground surface FR (see Figure 1) and along the X direction. The axis X30 is located on the opposite side from the main body portion 20 when viewed from the support columns 27, 27. The first gripping portion 31 is a cylindrical member with an insertion hole 311 formed inside. In the first gripping portion 31, the insertion hole 311 opens at one end 31a in the longitudinal direction. The first gripping portion 31 is fixed to the side surface of the reinforcing beam 29 via a connecting member 34.

[0024] The support cylinder 33 is a cylindrical member having a through hole 331 inside. The inner diameter D331 of the through hole 331 is the same as the inner diameter of the insertion hole 311 of the first gripping portion 31. The support cylinder 33 is provided with the through hole 331 oriented along the axis X30. The other end 33b of the support cylinder 33 is positioned between it and one end 31a of the first gripping portion 31 at a distance in the direction of the axis X30. The support cylinder 33 is fixed to the side surface of the reinforcing beam 29 via a connecting member 34.

[0025] The second gripping portion 32 has a first shaft portion 321, a second shaft portion 322, and a third shaft portion 323. The first shaft portion 321, the second shaft portion 322, and the third shaft portion 323 are arranged concentrically on a common axis X30. The first shaft portion 321 is formed with an outer diameter that matches the inner diameter D331 of the through hole 331 of the support cylinder 33. The first shaft portion 321 passes through the through hole 331 of the support cylinder 33 and is inserted into the insertion hole 311 of the first gripping portion 31. The second shaft portion 322 is larger than the first shaft portion 321 and has an outer diameter D322 that matches the support cylinder 33. The outer diameter of the third shaft portion 323 is larger than the outer diameter D322 of the second shaft portion 322.

[0026] In the first shaft portion 321, a stopper 35 is provided in the region located between the first gripping portion 31 and the support cylinder 33. The stopper 35 is fixed to the outer circumference of the first shaft portion 321 in a state where its movement in the direction of axis X30 is restricted. One end of the spring Sp, which is externally fitted onto the first shaft portion 321, is locked to the stopper 35. The other end of the spring Sp is locked to the support cylinder 33. The spring Sp applies a tensile force to the first shaft portion 321. As a result, the second gripping portion 32 is held in a position where the second shaft portion 322 is in contact with one end 33a of the support cylinder 33 from the direction of axis X30 due to the tensile force of the spring Sp. In the direction of axis X30, the second gripping portion 32 is displaceable relative to the first gripping portion 31.

[0027] A hook 36 is attached to the end 323a of the third shaft portion 323. The hook 36 has a base portion 361 and a locking portion 362. The hook 36 is formed by curving one end 36a of a strip-shaped member. The base portion 361 and the locking portion 362 are approximately perpendicular to each other. The boundary portion between the base portion 361 and the locking portion 362 has an arc shape with its vertex P pointing outward. In this embodiment, the arc-shaped boundary between the base portion 361 and the locking portion 362 is locked to the cylindrical frame 111 of the cart 1, thereby restricting the positional misalignment in the Y direction between the cart 1 and the assist device 2.

[0028] When inserting the main body 20 of the assist device 2 into the gap S (see Figure 1) between the cart 1 and the ground surface FR, the operator moves the assist device 2 by gripping the first gripping part 31 and the second gripping part 32. In this process, the second gripping part 32 is displaced away from the first gripping part 31 (downward in Figure 8), and after positioning the assist device 2 relative to the cart 1, the operator releases their hand from the second gripping part 32, causing the hook 36 to engage with the frame 111 of the cart 1 from the X direction due to the tensile force of the spring Sp. Therefore, the operator moving the assist device 2 can engage and disengage the hook 36 from the frame 111 of the cart 1 while still gripping the second gripping part 32 of the gripping parts 30 (first gripping part 31 and second gripping part 32) that they are gripping.

[0029] As shown in Figure 7, the support column 27 is provided with a support portion 37 for the switch button ST on the lower side of the reinforcing beam 29 in the Z direction. The support portion 37 has a first support portion 371 extending in the X direction from the side surface of the support column 27 (see Figure 8), and a second support portion 372 extending upward in the Z direction from the tip of the first support portion 371 (see Figure 7). The second support portion 372 is located outside the range of motion of the hook 36 (see dashed line in Figure 8). As shown in Figure 7, a switch button ST is installed at the upper end of the second support portion 372. The switch button ST is assigned functions such as switching the assist device 2 to travel, stop, forward, or reverse.

[0030] As shown in Figure 3, the support shafts 38 of the auxiliary wheels SW are provided in the lower regions of the support columns 27, 27. The assist device 2 is equipped with a pair of support shafts 38, 38 on both sides in the X direction. As shown in Figure 6, the support shaft 38 in the support column 27 is fixed to the side opposite to the plate member 25 via a pair of connecting members 39, 39. The support shaft 38 is positioned along the support column 27 in the Z-direction. The lower end 38a of the support shaft 38 is located below the main body 20. The auxiliary wheel SW is a fixed wheel with a defined direction of rotation. The auxiliary wheel SW is fixed to the lower end 38a of the support shaft 38. The direction of rotation of the auxiliary wheel SW coincides with the insertion direction (front-to-back direction in Figure 3) when inserting the main body 20 into the gap S between the cart 1 and the ground surface FR.

[0031] The connecting members 39, 39 of the support shaft 38 are positioned on the rear side of the support column 27 at a predetermined distance L39 away. The pair of connecting members 39, 39 are spaced apart in the vertical direction (Z direction), which enhances the support stability of the support shaft 38. As a result, the height h39 in the Z direction from the lower edge 20d of the main body 20 to the ground surface FR is always maintained at the same height.

[0032] Figures 9 and 10 illustrate the displacement mechanism 4 and the link mechanism 5. Figure 9 schematically shows a cross-section along line BB in Figure 3. Figure 10 schematically shows a cross-section along line CC in Figure 3. Figure 11 illustrates the operation of the displacement mechanism 4 and the link mechanism 5, and the transport of the cage cart 1.

[0033] As shown in Figure 5, a pair of drive wheels W, W are provided below the main body 20. The drive wheels W, W are connected to one end and the other end of the axle 41. On the axle 41, support frames 42, 42 are provided between the drive wheels W, W. As shown in Figure 9, the support frame 42 is a plate-shaped member provided below the main body 20, oriented along the Y direction (the insertion direction of the main body 20). The drive wheels W, W (axle 41: rotation axis Xw) are located approximately in the middle of the support frame 42 in the longitudinal direction (Y direction). As shown in Figure 5, the axles 41 of the drive wheels W, W pass through the support frames 42, 42 in the X direction. The axles 41 of the drive wheels W, W are rotatably supported by the support frames 42, 42. Between the support frames 42, 42, there is a drive motor (not shown) and a power transmission mechanism (not shown) that transmits the output rotation of the motor to the axles 41.

[0034] As shown in Figure 9, when viewed from the X direction, one end 42a (left side in the figure) of the support frame 42 is rotatably supported by a support shaft 43 provided on the support portion 481 of the fixed frame 48. The other end 42b (right side in the figure) of the support frame 42 is fixed to a support shaft 44 supported by a rod end 46. The support shafts 43 and 44 are provided parallel to the axle 41 (rotation axis Xw) of the drive wheel W. In the Y direction, the support shafts 43 and 44 are located on one side (left side in the figure) and the other side (right side in the figure) of the axle 41.

[0035] As shown in Figure 3, the support shaft 44 is oriented along the X direction. One end and the other end of the support shaft 44 are rotatably supported by rod ends 46, 46 fixed to the lower ends of the movable frames 45, 45. The movable frames 45, 45 are oriented along the Z direction. In the assist device 2, a pair of movable frames 45, 45 are provided in a symmetrical positional relationship with respect to the center line C2. As shown in Figure 9, a holder 47 is fixed to the plate member 25 on the side opposite to the main body 20. Viewed from the X direction, the holder 47 is provided in a range that crosses the support column 27 in the Y direction. A through hole 471 is provided in the region of the holder 47 on the tip 47a side of the support column 27, penetrating in the Z direction. The through hole 471 is formed with an inner diameter that matches the outer diameter D45 of the movable frame 45. The movable frame 45 passes through the through hole 471. The movable frame 45 is supported by the holder 47 so as to be movable in the Z direction.

[0036] As shown in Figure 9, in the assist device 2, when the movable frame 45 moves up and down in the Z direction, the support shaft 44 that supports the other end 42b of the support frame 42 moves up and down in conjunction with the movement of the movable frame 45, 45. Here, since one end 42a of the support frame 42 that supports the drive wheel W is rotatably supported by the support shaft 43 of the fixed frame 48, the other end 42b of the support frame 42 is displaced vertically around the support shaft 43. Therefore, when the movable frames 45, 45 are displaced downward on the ground surface FR side, the drive wheel W and the main body 20 are displaced relative to each other in the direction away from each other, as shown in Figures 11(a) to (c). Here, the drive wheel W is in contact with the ground surface FR. Therefore, the main body 20 is displaced upward in the direction away from the ground surface FR. At this time, the auxiliary wheels SW fixed to the main body 20 move upward away from the ground surface FR, so that ultimately only the drive wheels W are in contact with the ground.

[0037] As shown in Figure 9, the displacement mechanism 4 of the assist device 2 includes a support frame 42 that supports the axle 41 of the drive wheel W, a fixed frame 48 that rotatably supports one end 42a of the support frame 42, and a movable frame 45 that rotatably supports the other end 42b of the support frame 42. Here, the state shown in Figure 11(a) is the state in which the main body 20 is positioned in a self-supporting position where the drive wheels W and auxiliary wheels SW are in contact with the ground surface FR. The state shown in Figure 11(c) is the state in which the main body 20 is positioned in a transport position where the drive wheels W are in contact with the ground surface FR and the auxiliary wheels SW are lifted off the ground surface FR.

[0038] [Link mechanism] As shown in Figure 3, the assist device 2 is provided with a link mechanism 5 that links the raising and lowering of the movable frames 45, 45 to the operation of the control knob 55. As shown in Figure 10, the link mechanism 5 includes a fixing member 50 fixed to the main body 20, a first connecting member 51 connecting the operating knob 55 and the fixing member 50, and a second connecting member 52 connecting the first connecting member 51 and the movable frame 45.

[0039] As shown in Figure 10, the fixing member 50 is fixed to the plate member 25 on the side opposite to the main body 20 (the right side in the figure). The fixing member 50 is a plate-shaped member having a base portion 500 that extends in the Z direction along the plate member 25 and a connecting portion 501 that extends diagonally upward from the upper end of the base portion 500. As shown in Figure 4, the fixing members 50 are provided in pairs with a gap between them in the X direction. In the assist device 2, a pair of fixing members 50 are provided as a set with a gap between them in the X direction.

[0040] The tip 51a portion of the first connecting member 51 is inserted between the connecting portions 501, 501 of adjacent fixing members 50, 50. A connecting pin P1, supported by the connecting portions 501, 501 of the fixing members 50, 50, penetrates the region of the first connecting member 51 on the tip side 51a in the thickness direction. The region of the first connecting member 51 on the tip side 51a is rotatably supported by the connecting pin P1. As shown in Figure 9, when viewed from the X direction, the connecting pin P1 is connected to the first connecting member 51 on the central axis Za of the movable frame 45. The first connecting member 51 and the fixed member 50 are relatively displaceable in the circumferential direction about the axis (rotation axis X1) passing through the center of the connecting pin P1.

[0041] The first connecting member 51 is a plate-shaped member having a bent portion 511 on the tip 51a side. It also has a bent portion 512 between the bent portion 511 and the base end 51b. The first connecting member 51 is positioned with the outer vertex P of the bent portion 511 facing downwards and the outer vertex P of the bent portion 512 facing upwards. An operating knob 55 is fixed to the base end 51b of the first connecting member 51. As shown in Figure 3, the operating knob 55 connects the base ends 51b, 51b of one first connecting member 51 to the base end 51b of the other first connecting member 51.

[0042] As shown in Figure 9, the region of the bent portion 511 is connected to the region on the side of one end 52a of the second connecting member 52 via the connecting pin P2. As shown in Figure 4, the second connecting members 52 are provided in pairs, spaced apart in the X direction. The bent portion 511 of the first connecting member 51 is inserted between adjacent second connecting members 52, 52. A connecting pin P2, supported by the end portions 52a, 52a of the second connecting members 52, 52, penetrates the region of the bent portion 511 of the first connecting member 51 in the thickness direction. The first connecting member 51 and the second connecting members 52, 52 are rotatably connected by the connecting pin P2. The first connecting member 51 and the second connecting member 52 are relatively displaceable in the circumferential direction about the axis (rotation axis X2) passing through the center of the connecting pin P2.

[0043] As shown in Figure 4, a connecting piece 451 is provided at the upper end of the movable frame 45. At the upper end of the movable frame 45, the connecting piece 451 extends upward from the central part in the X direction. The other end 52b, 52b of the second connecting member 52 is located on both sides of the connecting piece 451. A connecting pin P3, supported in the region on the other end 52b, 52b of the second connecting member 52, penetrates the connecting piece 451 of the movable frame 45 in the thickness direction. The movable frame 45 and the second connecting members 52, 52 are rotatably connected by the connecting pin P3. As shown in Figure 9, when viewed from the X direction, the connecting pin P3 is connected to the second connecting member 52 on the central axis Za of the movable frame 45. The second connecting member 52 and the movable frame 45 (connecting piece 451) are relatively displaceable in the circumferential direction about the axis (rotation axis X3) passing through the center of the connecting pin P3.

[0044] In the link mechanism 5, the connecting pins P1, P2, and P3 are arranged parallel to each other. As a result, the rotation axis X1 when the fixed member 50 and the first connecting member 51 are displaced relative to each other, the rotation axis X2 when the bent portion 511 of the first connecting member 51 and the region on the end 52a side of the second connecting member 52 are displaced relative to each other, and the rotation axis X3 when the region on the end 52b side of the second connecting member 52 and the connecting piece 451 of the movable frame 45 are displaced relative to each other. Furthermore, the connecting pins P1, P2, and P3 are provided parallel to the axle 41 (rotation axis Xw) of the drive wheel W and the support axes 43 and 44 of the support frame 42. As shown in Figure 9, when viewed from the X direction, connecting pins P1 (rotation axis X1) and P3 (rotation axis X3) are located on the central axis Za of the movable frame 45. Connecting pin P2 (rotation axis X2) can be displaced between the central axis Za and one side of the central axis Za (right side in the figure) during the operation of the operating knob 55 (see Figures 11(a) to (c)).

[0045] As shown in Figures 11(a) to 11(c), when the operating knob 55 of the first connecting member 51 is operated to displace the first connecting member 51 downward in the circumferential direction around the pivot axis X1, the connection point (pivot axis X2) between the bent portion 511 of the first connecting member 51 and the second connecting member 52 is displaced in the circumferential direction around the connection point (pivot axis X1) between the fixed member 50 and the first connecting member 51, and the position of the connection point (pivot axis X2) moves downward in the Z direction. As a result, the connection point (rotation axis X3) between the second connecting member 52 and the connecting piece 451 of the movable frame 45 moves downward in the Z direction. This causes the movable frame 45 to move downward in the Z direction. As a result, in the displacement mechanism 4 of the assist device 2, the other end 42b of the support frame 42 that supports the axle 41 of the drive wheel W rotates around the support shaft 43 on the one end 42a, causing the drive wheel W and the main body 20 to be displaced relative to each other in a direction away from each other. Here, the drive wheel W is in contact with the ground surface FR. Therefore, the main body 20 is displaced upward in a direction away from the ground surface FR. At this time, the auxiliary wheel SW, which is supported by the main body 20 via the support shaft 38, also moves together with the main body 20 in a direction away from the ground surface FR, and is lifted off the ground.

[0046] In this way, the assist device 2 is equipped with a link mechanism 5, which allows the movable frames 45, 45 to be raised and lowered in conjunction with the operation of the operating knob 55, thereby relatively displacing the drive wheel W and the main body 20 in a direction away from each other.

[0047] [Engagement / Disengagement Mechanism] Figures 12 and 13 illustrate the engagement / disengagement mechanism 6. Figure 12 schematically shows a cross-section along the DD line in Figure 3. Figure 13 shows a perspective view of the engagement / disengagement mechanism 6 from diagonally above.

[0048] As shown in Figures 12 and 13, the assist device 2 is provided with a locking / unlocking mechanism 6 that engages and disengages the locking claw 611 with the cart 1 in conjunction with the raising and lowering of the movable frames 45, 45. The engagement / disengagement mechanism 6 includes an interlocking frame 60 that moves up and down in conjunction with the raising and lowering of the movable frames 45, 45, a movable plate 61 equipped with a locking claw 611, connecting members 62, 62 that connect the interlocking frame 60 and the movable plate 61, and a guide holder 64 that movably supports the guide shafts 63, 63 connected to the movable plate 61.

[0049] As shown in Figure 3, an interlocking frame 60 is provided between the movable frame 45 on one side (left side in the figure) and the movable frame 45 on the other side (right side in the figure), oriented along the X direction. The interlocking frame 60 is provided coaxially with respect to the aforementioned connecting pin P3. Connecting pins P3, which pass through the connecting pieces 451 and the second connecting members 52, 52, are press-fitted into both ends of the interlocking frame 60. The connecting pins P3, P3 and the interlocking frame 60 are connected in a way that prevents relative rotation. Therefore, the interlocking frame 60 moves up and down in conjunction with the raising and lowering of the movable frame 45.

[0050] As shown in Figure 12, a screw hole 601 is open at the top of the interlocking frame 60. The lower end 62b of the connecting member 62 is screwed into the screw hole 601. The lower end 62b of the connecting member 62 is restricted from moving away from the interlocking frame 60 by a nut N. As shown in Figure 3, the connecting member 62 is positioned symmetrically with respect to the center line C2 in the width direction (center line C2 in the X direction) of the assist device 2.

[0051] As shown in Figure 12, the upper end 62a of the connecting member 62 is screwed into a screw hole 612 provided in the base 610 of the movable plate 61. A nut N is screwed into the upper end 62a of the connecting member 62. The movement of the connecting member 62 in the Z direction is restricted by the nut N. At the base 610 of the movable plate 61, a screw hole 613 is provided at a position offset in the Y direction from the screw hole 612. The upper end 63a of the guide shaft 63 is screwed into the screw hole 613. A nut N is screwed into the upper end 63a of the guide shaft 63. The movement of the guide shaft 63 in the Z direction is restricted by the screw hole 613 and the nut N.

[0052] As shown in Figure 5, the guide shaft 63 is also positioned symmetrically with respect to the center line C2 in the width direction (center line C2 in the X direction) of the assist device 2. As shown in Figure 3, when viewed from the Y direction, the guide shaft 63 overlaps with the aforementioned connecting members 62, 62. As shown in Figure 12, the lower end 63b of the guide shaft 63 is supported by a guide holder 64 located below the movable plate 61, allowing it to move in the vertical direction.

[0053] The guide holder 64 is fixed to the plate member 25 on the side opposite to the main body 20. When viewed from the X direction, the guide holder 64 is positioned to overlap with the aforementioned support columns 27, 27. As shown in Figure 3, the guide holder 64 is located between the holders 47, 47 of the displacement mechanism 4. As shown in Figure 12, the guide holder 64 is provided with a through hole 641 that penetrates vertically. The guide shaft 63 passes through the through hole 641 vertically. The vertical movement of the guide shaft 63 is guided by the through hole 641 of the guide holder 64.

[0054] As described above, the interlocking frame 60 moves up and down in conjunction with the raising and lowering of the movable frames 45, 45. The movable plate 61 is fixed to the interlocking frame 60 via a connecting member 62 so that it cannot be displaced relative to it. Therefore, when the movable frames 45, 45 move up and down, the movable plate 61 also moves up and down. The movable plate 61 has a base portion 610 oriented along the Y direction. The base portion 610 is provided from above the movable frame 45, crossing the guide holder 64 and the plate member 25. The tip 610a of the base portion 610 is located above the main body portion 20. The tip 610a of the base portion 610 is provided with a locking claw 611 that extends downward toward the main body portion 20.

[0055] As shown in Figure 5, the plate member 25 is provided with a recess 251 in the center in the X direction. The recess 251 is formed as a recess below the main body 20 side. The recess 251 opens to the upper part 25c of the plate member 25. The recess 251 is formed with a width W251 in the X direction, which is wider than the width W611 of the locking claw 611. The recess 251 is provided to avoid interference with the movable plate 61 which moves up and down.

[0056] In the assist device 2, when the drive wheels W, W are positioned in a self-supporting position (see Figure 11(a)), the drive wheels W, W and the auxiliary wheels SW, SW come into contact with the ground surface FR. As a result, the assist device 2 is supported at a total of four points, effectively preventing it from tipping over. When moving the assist device 2, the assist device can be easily moved by gripping the gripping part 30 (see Figure 8) and tilting the assist device so that only the auxiliary wheels SW, SW touch the ground (see Figure 1). After inserting the main body 20 into the gap S between the cart 1 and the ground surface FR (floor surface) (see Figure 11(d)), the operating knob 55 is operated. As a result, the main body 20 and the drive wheels W are displaced relative to each other in the vertical direction, causing one side of the cart 1 to be lifted by the main body 20 inserted into the gap S, and only the pair of free wheels 12, 12 on the other side to touch the ground. In other words, when the drive wheels W, W are positioned in the transport position (see Figure 11(c)), one side of the cart 1 can be lifted, leaving only the pair of free wheels 12, 12 on the other side in contact with the ground (see Figure 11(e)). In this state, when the cart 1 is transported by the driving force of the drive wheels W, W, the auxiliary wheels SW, SW are not in contact with the ground, thus effectively preventing situations where the auxiliary wheels SW, SW get stuck in grooves or other obstacles along the transport path, hindering the transport of the cart 1.

[0057] Furthermore, during the process of positioning the drive wheels W, W in the transport position, as shown in Figure 13, the locking claw 611 of the locking / unlocking mechanism 6 is displaced downward toward the main body 20 in conjunction with the raising and lowering of the movable frames 45, 45. When the cart 1 is placed on the main body 20, the lowered locking claw 611 engages with the strip-shaped plate 13 provided along the side edge of the bottom wall 10 of the cart 1 (see Figure 13). As a result, when the assist device 2 is towing and moving the cart 1, even if the cart 1 tries to move in a direction that would cause it to detach from the main body 20 (downward and to the left in Figure 13), the locking claw 611 on the assist device 2 side is engaged with the strip-shaped plate 13, preventing the cart 1 from moving. This prevents the cart 1 from separating from the assist device 2 while it is being transported by the assist device 2.

[0058] Figure 14 illustrates an assist device 2A according to a modified example. Figure 14(a) shows the rod 76 in a retracted state. Figure 14(b) shows the rod 76 in an extended state. In the above-described embodiment, an assist device 2 was provided which is configured to raise and lower the movable frame 45 by rotating the operating knob 55 around the pivot axis X1. The rotation of the operating knob 55 around the pivot axis X1 may be performed by the actuator 7. As shown in Figure 14(a), a mounting bracket 71 provided at the base end of the actuator 7 is rotatably attached to the support column 27 of the assist device 2A. The actuator 7 has a cylinder 75 and a rod 76 that is movable forward and backward by the cylinder 75. In cylinder 75, rod 76 is provided so as to be movable forward and backward along a central axis Z7 that runs along the longitudinal direction of cylinder 75. The tip of the rod 76 is rotatably connected to the operating knob 55. As shown in Figure 14(b), in the assist device 2A, when the rod 76 is extended, the operating knob 55, which is pushed by the rod 76, is displaced circumferentially around the pivot axis X1, displacing the operating knob 55 downward in the Z direction. During the extension of the rod 76, the base end of the actuator 7 also rotates around the pivot axis X7. As a result, the actuator 7 extends the rod 76 while changing the angle around the pivot axis X7, displacing the operating knob 55 downward toward the ground surface FR. This allows the movable frame 45 to descend, causing the drive wheels W, W and the main body 20 to be displaced relative to each other in the Z direction.

[0059] When raising the movable frame 45, the operating knob 55 can be moved towards the initial upward position by retracting the rod 76. Alternatively, instead of the operating knob 55, the movable frame 45 may be raised and lowered directly by the actuator 7.

[0060] Figures 15 and 16 illustrate an assist device 2B according to another embodiment. The assist device 2B differs from the assist device 2 described above in that the main body 20 is equipped with a coil spring (spring Sp1) as an elastic member, and a free wheel SW1 is provided on the front end 20a side of the main body 20.

[0061] As shown in Figure 15, the main body 20 of the assist device 2B is formed in a roughly rectangular shape from a pair of side frames 21, 21 that are spaced apart and parallel to each other, and a pair of reinforcing frames 22, 23 that connect the pair of side frames 21, 21 to each other.

[0062] At the front end 20a side of the main body 20, a free wheel SW1 is provided on the lower surface of the reinforcing frame 22. As shown in Figure 16, the free wheel SW1 is positioned so as to contact the ground surface FR together with the drive wheels W, W and the auxiliary wheels SW, SW when the main body 20 is in a self-supporting position.

[0063] On the rear side of the main body 20 (the side with the plate member 25), a reinforcing frame 23 is provided with a gap between it and the plate member 25. Between the reinforcing frame 23 and the plate member 25, a pair of springs Sp1, Sp1 are housed with their positions aligned in the insertion direction (Y direction) of the main body 20, and spaced apart in the width direction (X direction).

[0064] As shown in Figure 16, a spring holder 24 is provided between the reinforcing frame 23 and the plate member 25. The spring holder 24 is fixed in place, sandwiched between the reinforcing frame 23 and the plate member 25. The spring holder 24 has a thinner thickness than the reinforcing frame 23.

[0065] The spring holder 24 has a pair of cylindrical portions 241, 241. Springs Sp1, Sp1 are externally fitted into and positioned within the cylindrical portions 241, 241, respectively. In this state, the springs Sp1, Sp1 protrude upward from the upper surface 20c of the main body 20 by a height Δh. The height Δh is set so that when the main body 20 of the assist device 2 is inserted into the gap S between the cart 1 and the ground surface FR, it does not interfere with the bottom wall 10 of the cart 1 (see Figure 17).

[0066] Figures 17 to 20 illustrate the operation of the displacement mechanism 4 and the link mechanism 5, and the transport of the cage cart 1. In Figures 17 to 20, the free wheel 12 located on the side into which the assist device 2B is inserted is shown with a hidden line. When transporting the cart 1 using the assist device 2B, the main body 20 is inserted into the gap S between the cart 1 and the ground surface FR (floor surface) (see Figure 17), and the plate member 25 of the main body 20 is positioned in contact with the cart 1 (see Figure 18). In this state, the spring Sp1 is positioned opposite the bottom wall 10 of the cart 1 with a gap between them. Furthermore, the free wheels 12 of the cart 1, the free wheel SW1 of the assist device 2B, the drive wheel W, and the auxiliary wheel SW are all in contact with the ground surface FR.

[0067] Next, when the operating knob 55 is displaced downward, the circumferential displacement of the operating knob 55 around the rotation axis X1 is converted by the link mechanism 5 into vertical displacement (direction of the central axis Za) of the movable frame 45. As a result, the displacement mechanism 4 causes the other end 42b of the support frame 42 that supports the axle 41 of the drive wheel W to rotate around the support shaft 43 on the one end 42a, causing the drive wheel W and the main body 20 to be displaced relative to each other in a direction away from each other. Here, the drive wheel W is in contact with the ground surface FR. Therefore, the main body 20 is displaced upward in the direction away from the ground surface FR. At this time, the auxiliary wheel SW supported by the main body 20 via the support shaft 38 and the free wheel SW1 supported by the main body 20 also move together with the main body 20 in a direction away from the ground surface FR, and they leave the ground surface FR (see Figure 19).

[0068] As the main body 20 moves upward away from the ground surface FR, the spring Sp1 protruding from the upper surface of the main body 20 comes into contact with the bottom wall 10 of the cart 1 from below. In this case, if a heavy object (workpiece) is loaded onto the cart 1, the situation will not be as described in the assist device 2 above, where one side of the cart 1 into which the main body 20 is inserted is lifted (see Figure 11(e)). The spring Sp1 is pressed and compressed by the cart 1 (see Figure 20).

[0069] The compressed spring Sp1 exerts a biasing force on the main body 20 that pushes the entire assist device 2B downward toward the ground surface FR. As a result, since the movement of the main body 20 away from the ground surface FR (upward in the figure) is restricted by the weight of the cart 1, a biasing force acts on the drive wheel W, which is located between the main body 20 and the ground surface FR, in a direction that pushes it toward the ground surface FR. Consequently, the drive wheel W is held in a state of being pressed against the ground surface FR.

[0070] In this state, when the drive wheel W of the assist device 2B is driven, the drive wheel W can grip the ground surface FR and rotate reliably. As a result, with the four free wheels 12 of the cart 1 in contact with the ground, the cart 1 can be moved by the driving force of the assist device 2B, which has the drive wheel W pressed against the ground surface FR. In this case, since the auxiliary wheels SW, SW and the free wheel SW1 of the assist device 2B are not in contact with the ground, it is possible to effectively prevent situations in which the auxiliary wheels SW, SW or the free wheel SW1 get stuck in grooves or other obstacles on the transport path, thereby hindering the transport of the cart 1.

[0071] In this case, if the weight of the heavy object (workpiece) loaded on the cart 1 is relatively small, the driving force of the drive wheels W may be excessive for moving the cart 1. Therefore, the assist device 2B may be equipped with a mechanism for adjusting the driving force of the drive wheels W, so that the driving force is adjusted according to the weight of the cart 1.

[0072] In this way, the assist device 2B inserts the main body 20 into the gap S between the cart 1 and the ground surface FR, and then presses the main body 20 against the lower surface of the cart 1 to compress the spring Sp1. The biasing force of the compressed spring Sp1 presses the drive wheels W, W against the ground surface. Then, the driving force of the drive wheels W, W provided by the assist device 2B moves the cart 1. Therefore, even when the weight of the heavy object (workpiece) being transported by the cart 1 is large, the cart 1 can be moved appropriately.

[0073] Furthermore, the configuration of the assist device 2B according to other embodiments may be arbitrarily combined with the configuration of the assist device 2 according to the embodiment or the assist device 2A according to the modified version. In this case as well, the same functions and effects as in the above-described embodiments and modified versions will be achieved.

[0074] As described above, the assist device 2 according to this embodiment has the following configuration. (1) The assist device 2 is used to transport the cage cart 1 equipped with wheels (free wheels 12). The assist device 2 includes a main body 20 that is inserted from one side of the cart 1 into the gap S formed between the free wheel 12 and the cart 1 and the ground surface FR, Driven by a power source, drive wheels W, W and It is fixed to the main body 20, and the auxiliary wheels SW, SW are smaller in diameter than the drive wheels W, It has a drive wheel W, a displacement mechanism 4 that causes relative displacement between W and the main body 20 in the vertical direction (Z direction) with respect to the contact surface FR. The displacement mechanism 4 displaces the main body 20 between a self-supporting position (see Figure 10) in which the drive wheels W, W and auxiliary wheels SW, SW are in contact with the ground surface FR, and a transport position (see Figure 10) in which the drive wheels W, W are in contact with the ground surface FR, while the auxiliary wheels SW, SW are lifted off the ground surface FR.

[0075] According to the embodiment, after inserting the main body 20 into the gap S between the cart 1 and the ground surface FR from one side of the cart 1 which has free wheels 12 at its four corners, the displacement mechanism 4 displaces the drive wheels W, W away from the main body 20, causing the main body 20 and the auxiliary wheels SW fixed to the main body 20 to be displaced away from the ground surface FR. This allows the auxiliary wheels SW to be positioned away from the ground surface FR, and one side of the cart 1 into which the main body 20 is inserted can be lifted, so that the cart 1 is supported with only the free wheels 12 on the other side touching the ground (see Figure 11(e)). In this state, when the trolley 1 is transported by the driving force of the drive wheels W, W, the auxiliary wheels SW, SW are not in contact with the ground, so it is possible to effectively prevent situations in which the auxiliary wheels SW, SW get stuck in grooves or other obstacles on the transport path, thereby hindering the transport of the trolley 1. Furthermore, since there is no need to increase the diameter of the auxiliary wheels SW, there is no interference between the drive wheels W and the auxiliary wheels SW. Furthermore, when the assist device 2 is not in use for transporting the cart 1, the drive wheels W, W and auxiliary wheels SW can be placed on the ground surface FR, allowing the assist device 2 to stand on its own. In this case, the assist device 2 in its self-supporting state requires less storage space than when it is lying down. Therefore, the assist device 2 can be stored in a self-supporting state in any available space in the factory, eliminating the need to secure a large space within the factory for storing the assist device 2.

[0076] When all four free wheels 12 of the cart 1 are in contact with the ground, the rolling resistance of the free wheels 12 may change due to mats laid on the transport path, and if the orientation of at least one free wheel 12 changes to a direction perpendicular to the transport direction at the moment the rolling resistance changes, the movement of the cart 1 will be hindered. As described above, by keeping only the other pair of free wheels 12 in contact with the ground and towing with the assist device 2, the possibility of the orientation of the free wheels 12 changing to a direction that hinders transport can be reduced even if the rolling resistance of the contact surface FR changes.

[0077] (2) The displacement mechanism 4 is The main body 20 includes movable frames 45, 45 that are supported so as to be displaceable in the vertical direction (Z direction), The main body 20 is provided on the ground surface FR side in an orientation along the insertion direction (Y direction) and has support frames 42, 42 that support the drive wheels W, W. The support frames 42, 42 are rotatably supported at one end 42a in the longitudinal direction by the main body 20, and at the other end 42b by the movable frame 45.

[0078] According to this embodiment, since one end 42a of the support frames 42, 42 is cantilevered by the main body 20, when the movable frames 45, 45 are displaced vertically, the other end 42b of the support frames 42, 42 is displaced vertically with the support point (support shaft 43) on the one end 42a as the pivot point. As a result, the drive wheels W, W supported by the support frames 42, 42 are displaced relative to the main body 20 in the vertical direction, causing the main body 20 to be displaced from the self-supporting position toward the transport position. In other words, the displacement of the movable frames 45, 45 causes the drive wheels W, W and the main body 20 to be displaced relative to each other, thereby allowing the main body 20 to be displaced between a self-supporting position and a transport position.

[0079] (I) At the front end 20a of the main body 20, which is located on the insertion side, one end 42a of the support frame 42, 42 is rotatably supported. A holder 47 is provided on the side edge of the main body 20 opposite to the front end 20a (base end 20b side) to support the movable frame 45, 45 so that it can move in the vertical direction. When viewed from the vertical direction (Z direction), the drive wheels W, W are positioned so as to overlap with the main body 20.

[0080] The assist device 2 can be effectively prevented from becoming larger in the insertion direction (Y direction) and in the direction perpendicular to the insertion direction (X direction) of the main body 20. In this case, when viewed from the vertical direction (Z direction), if the drive wheels W, W are positioned at an offset position from the main body 20 (a position where they do not overlap with the main body 20), the load of the cart 1 is also applied to the part connecting the main body 20 and the drive wheels W, W. Therefore, it becomes necessary to ensure the overall rigidity and strength of the main body 20, including the connecting part. As described above, the drive wheels W, W are positioned so that they overlap with the main body 20 when viewed from above, so that the drive wheels W, W are positioned directly below the main body 20 that supports the bottom wall 10 of the cart 1 from below. This allows the drive wheels W, W and the main body 20 to be displaced relative to each other in the vertical direction, thereby lifting one side of the cart 1. The load of the cart 1 can then be supported by the drive wheels W, W located directly below the main body 20. This improves the support stability of the cart 1 without reinforcing the rigidity of the main body 20.

[0081] (3) The movable frames 45, 45 are connected to the operating knob 55 via the link mechanism 5. The link mechanism 5 converts the operation of the control knob 55 into vertical displacement of the movable frames 45, 45.

[0082] According to this embodiment, the main body 20 can be displaced between the self-supporting position and the transport position by operating the operating knob 55, without directly manipulating the movable frames 45, 45.

[0083] (4) The link mechanism 5 is A fixing member 50 fixed to the main body 20, A first connecting member 51 connects the operating knob 55 and the fixing member 50, and has a bent portion 511 on one end (tip 51a) in the longitudinal direction, It has a second connecting member 52 that connects the movable frame 45 and the first connecting member 51, The first connecting member 51 has a first connecting point (connecting pin P1) that is rotatably connected to the fixing member 50, located on one end 50a side of the bent portion 511. The second connecting member 52 has a second connecting point (connecting pin P2) on one end (one end 52a) in the longitudinal direction that is rotatably connected to the bent portion 511 of the first connecting member 51, and a third connecting point (connecting pin P3) on the other end (the other end 52b) in the longitudinal direction that is rotatably connected to the movable frame 45. When viewed from the X direction, connecting pins P1 and P3 are located on the central axis Za of the movable frame 45.

[0084] According to this embodiment, the circumferential displacement operation of the operating knob 55 around the rotation axis X1 is converted by the link mechanism 5 into vertical displacement (central axis Za direction) of the movable frame 45. Therefore, the operator using the assist device 2 can easily displace the main body 20 between the self-supporting position and the transport position simply by operating the operating knob 55.

[0085] (II) The pivot axis X1 (first pivot axis) passing through the first connection point (connecting pin P1), the pivot axis X2 (second pivot axis) passing through the second connection point (connecting pin P2), and the pivot axis X3 (third pivot axis) passing through the third connection point (connecting pin P3) are parallel to the axis of rotation Xw of the drive wheels W.

[0086] The main body 20 can be displaced between a self-supporting position and a transport position by raising and lowering the operating knob 55 in the circumferential direction around the pivot axis X1.

[0087] (III) When the drive wheels W, W are positioned in the transport position, the pivot axis X1, pivot axis X2, and pivot axis X3 are located on the central axis Za of the movable frame 45 when viewed from the X direction. When the drive wheels W, W are positioned in an independent position, when viewed from the X direction, the pivot axis X1 and pivot axis X3 are located on the central axis Za of the movable frame 45, and the pivot axis X2 is positioned offset to one side in the Y direction relative to the central axis Za. With this configuration, the vertical range of movement of the movable frame 45 can be secured by the sum of the length L1 from the bent portion 511 of the first connecting member 51 to its tip 51a and the length L2 of the second connecting member 52, which is L (= L1 + L2). By adjusting lengths L1 and L2, the tilt of the cart 1 when lifted by the main body 20 can be adjusted to a desired tilt.

[0088] In particular, when the drive wheels W, W are positioned in the transport position, (a) when viewed from the X direction, the pivot shafts X1 and X3 are aligned on the central axis Za of the movable frame 45, preferably (b) when viewed from the X direction, the pivot shafts X1 and X3 are aligned on the central axis Za of the movable frame 45, and the pivot shaft X2 is positioned offset to the other side in the Y direction with respect to the central axis Za. With this configuration, a considerable operating force is required to move the pivot axis X2 to one side in the radial direction of the central axis Za. In other words, a locking mechanism can be configured that restricts the upward movement of the movable frame 45 until a considerable operating force is applied to the operating knob 55 in the upward direction. This provides a holding force that keeps the drive wheels W, W in the transport position. Therefore, since the drive wheels W, W can be brought into contact with the ground surface FR, and the auxiliary wheels SW can be kept in a lifted state, the possibility that the movable frame 45 will be displaced in a direction that moves closer to the main body 20 when the cart 1 is being transported by the assist device 2 will be reduced, thereby reducing the possibility that the posture of lifting and tilting the cart 1 will be disrupted.

[0089] (5) The device is equipped with an actuator 7 that displaces the operating knob 55 in the circumferential direction around the rotation axis X1.

[0090] According to this embodiment, the displacement of the drive wheels W, W between the self-supporting position and the transport position can be automated by operating the control knob 55.

[0091] (6) In the main body 20 of the assist device 2B, a spring Sp1 (coil spring) as an elastic member is provided in the region that is inserted into the gap S. When the main body 20 is positioned in a self-supporting position, the spring Sp1 protrudes from the upper surface 20c of the main body 20, and when the main body 20 is positioned in a transport position, it is compressed by the cage car 1, generating a biasing force that presses the drive wheel W against the ground surface FR.

[0092] According to this embodiment, when the main body 20 is positioned in the transport location, the spring Sp1 is pressed and compressed by the cart 1, applying a biasing force to the main body 20 that presses the entire assist device 2B downwards on the ground surface FR side (see Figure 20). This biasing force acts in a direction that presses the drive wheel W, which is located between the main body 20 and the ground surface FR, against the ground surface FR. As a result, the drive wheel W is held in a state of being pressed against the ground surface FR. In this state, when the drive wheel W of the assist device 2B is driven, the drive wheel W can grip the ground surface FR and rotate reliably. As a result, the cart 1 can be moved by the driving force of the assist device 2B, which has the drive wheel W pressed against the ground surface FR, while the four free wheels 12 of the cart 1 remain in place.

[0093] (7) It has a locking claw 611 that moves vertically in conjunction with the displacement of the movable frame 45. When the main body portion 20 of the locking claw 611 is inserted into the gap S between the bottom wall portion 10 of the cart 1 and the ground surface FR, and the drive wheels W, W are positioned in the transport position, the locking claw 611 engages with the cart 1 (strip plate 13: see Figure 13), and when the drive wheels W, W are positioned in the self-supporting position, the locking claw 611 disengages from the cart 1 (strip plate 13).

[0094] With this configuration, when transporting the cart 1 using the assist device 2, the locking claws 611 can prevent the cart 1 from falling off the main body 20. This ensures that the cart 1 is transported reliably by the assist device 2.

[0095] (IV) The movable frame 45 has a locking / disengaging mechanism 6 that engages and disengages the locking claw 611 from the cart 1 in conjunction with the displacement of the movable frame 45. In the assist device 2, movable frames 45, 45 are provided at intervals in the width direction (X). The engagement / disengagement mechanism 6 is One end and the other end in the longitudinal direction are connected to one movable frame 45 and the other movable frame 45, and an interlocking frame 60 that moves up and down in conjunction with the raising and lowering of the movable frames 45, 45, A movable plate 61 is positioned so that the tip end, which is provided with the locking claw 611, is positioned above the main body 20, A pair of connecting members 62, 62 that connect the interlocking frame 60 and the movable plate 61, A pair of guide shafts 63, 63 connected to the movable plate 61, The device includes a guide holder 64 which is fixed to the main body 20 and has through holes 641 that support the guide shafts 63, 63 so as to be movable in the vertical direction. When viewed from the insertion direction (Y direction) of the main body 20, the pair of connecting members 62, 62 and the pair of guide shafts 63, 63 are arranged in an overlapping positional relationship.

[0096] With this configuration, the engagement / disengagement mechanism 6 can be provided by utilizing the gap in the X direction between the movable frames 45, 45, so that the engagement / disengagement mechanism 6 can be provided without increasing the size of the assist device 2 in the X direction. Furthermore, because the pair of connecting members 62, 62 and the pair of guide shafts 63, 63 are arranged in an overlapping position, the locking claw 611 provided on the movable plate 61 can be raised and lowered while maintaining a horizontal position, and engaged with and disengaged from the strip-shaped plate 13 on the cart 1 side.

[0097] (8) Support columns 27, 27 extending upward from the main body 20, The support columns 27, each having a gripping portion 30 provided at the upper end of the 27 in a direction along the horizontal line. The gripping portion 30 is The first gripping part 31 is fixed to the support column 27, A second gripping portion 32 is provided with respect to the first gripping portion 31 so as to be displaceable in a direction perpendicular to the insertion direction of the main body portion 20 (X direction), The second gripping portion 32 extends in the insertion direction (Y direction) and has a hook 36 at its tip that engages with and disengages from the frame 111 of the cart 1.

[0098] According to this embodiment, the hook 36 can be secured to the cylindrical frame 111 of the cart 1, thereby restricting the misalignment of the cart 1 and the assist device 2 in the Y direction. Here, the height of the cart 1 is higher than that of the assist device 2 (see Figure 1). Therefore, if the cart 1 is fixed only by the locking claws 611 located on the lower side of the assist device 2, the upper area where the gripping portion 30 of the assist device 2 is provided may not be stable when transporting the cart 1 using the assist device 2, especially immediately after the start of transport. A gripping portion 30 is provided on the upper end of the support column 27, and a hook 36 that engages with the frame 111 of the cart 1 is provided on it. Using the locking claw 611 and the hook 36, the cart 1 can be supported at two points, upper and lower, in the Z direction. This further improves the support stability of the cart 1 during transport.

[0099] Although embodiments of the present invention have been described above, these embodiments are merely examples of how the present invention can be applied, and are not intended to limit the technical scope of the present invention to the specific configurations of these embodiments. Modifications can be made as appropriate within the scope of the technical idea of ​​the invention. [Explanation of Symbols]

[0100] 1: Cage cart, 2, 2A, 2B: Assist device, 4: Displacement mechanism, 5: Link mechanism, 7: Actuator, 12: Free wheel, 13: Strip plate, 20: Main body, 27: Support column, 30: Gripping part, 42a: One end, 42b: Other end, 45: Movable frame, 50: Fixing member, 51: First connecting member, 51a: Tip, 52: Second connecting member, 52a: End (one end), 52b: End (the other end), 55: Operating knob, 111: Frame, 511: Bending part, 611: Locking claw, FR: Ground contact surface, P1: Connecting pin (first connection point), P2: Connecting pin (second connection point), P3: Connecting pin (third connection point), S: Gap, SP1: Spring (elastic member), SW: Auxiliary wheel, W: drive wheel, Za: central axle

Claims

1. An assist device used for transporting wheeled carts, The main body portion is inserted from one side of the cart into the gap formed between the wheel and the ground surface, Driven wheels driven by a power source, Auxiliary wheels, which are fixed to the main body and have a smaller diameter than the drive wheels, It has a displacement mechanism that causes relative displacement between the drive wheel and the main body in the vertical direction with respect to the ground surface, The displacement mechanism is an assist device that displaces the main body between a self-supporting position in which the drive wheel and the auxiliary wheel are in contact with the ground surface and a transport position in which the drive wheel is in contact with the ground surface and the auxiliary wheel is lifted off the ground surface.

2. In claim 1, The displacement mechanism is, The main body includes a movable frame that is supported so as to be displaceable in the vertical direction, The main body has a support frame that is provided on the ground surface side of the main body in a direction along the direction in which the main body is inserted into the cart, and that supports the drive wheel, An assist device in which the support frame is rotatably supported at one end in the longitudinal direction by the main body and rotatably supported at the other end by the movable frame.

3. In claim 2, The aforementioned movable frame is connected to the operating knob via a link mechanism. The link mechanism is an assist device that converts the operation of the operating knob into the vertical displacement of the movable frame.

4. In claim 3, The aforementioned link mechanism is A fixing member fixed to the main body, A first connecting member connects the operating knob and the fixing member and has a bent portion on one end in the longitudinal direction, It has a second connecting member that connects the movable frame and the first connecting member, The first connecting member has a first connecting point on one end side of the bent portion that is rotatably connected to the fixing member, The second connecting member has a second connecting point rotatably connected to the bent portion of the first connecting member on one end in the longitudinal direction, and a third connecting point rotatably connected to the movable frame on the other end in the longitudinal direction. An assist device in which the first and third connection points are located on the central axis of the movable frame.

5. In claim 4, An assist device comprising an actuator that displaces the aforementioned operating knob in the circumferential direction around the pivot axis.

6. In any one of claims 1 to 5, In the main body, an elastic member is provided in the region that is inserted into the gap. The elastic member is an assist device that protrudes from the upper surface of the main body when the main body is positioned in the self-supporting position, and is compressed by the cart when the main body is positioned in the transport position, generating a biasing force that presses the drive wheel against the ground surface.

7. In any one of claims 2 to 5, The movable frame has a locking claw that moves in the vertical direction in conjunction with the displacement of the movable frame, The locking claw is an assist device in which, with the main body inserted into the gap, the drive wheel engages with the cart when it is positioned in the transport position, and the engagement with the cart is released when the drive wheel is positioned in the self-supporting position.

8. In any one of claims 2 to 5, A support column extending upward from the main body, The support column has a gripping portion provided at its upper end, oriented along the horizontal line, The gripping portion is, A first gripping portion fixed to the support column, A second gripping portion is provided with respect to the first gripping portion so as to be displaceable in a direction perpendicular to the insertion direction of the main body portion, An assist device having a hook at its tip that extends from the second gripping portion toward the insertion direction and engages with and disengages from the frame of the trolley.

Images