Transport equipment

Abstract

The mechanism for lifting and lowering the pallet can be positioned even in low-profile spaces, and heavy pallets can be easily lifted manually. [Solution] Multiple lifting link mechanisms 20A to 20D are provided at various locations on the frame 10. The lifting link mechanisms 20A to 20D are configured to form a triangular shape that protrudes upward in a side view by pulling the drive link 22. The drive mechanism 30 includes a rotating member 31 that is supported to be rotatable around a pivot axis 31a extending in the vertical direction, pulling members 32A to 32D connected to the drive link 22 on the side of the rotating member 31 closer to the pivot axis 31a than the outermost part of the rotating member 31, and a conversion mechanism 40 that converts rotational force around a horizontal axis input by the foot pedal 50 into rotational force around an axis extending in the vertical direction. The rotational force converted by the conversion mechanism 40 is input to the radially outward side of the rotating member 31.

Description

Technical Field

[0001] The present disclosure relates to a carrier with casters for carrying heavy objects such as pallets, for example.

Background Art

[0002] Conventionally, for example, when loading and unloading heat-treated products on a product processing line, a series of operations are sometimes repeatedly performed, in which a pallet loaded with products is lifted by a hydraulic hand lift stacker and moved to a predetermined location, and then an empty pallet is installed by replacement after the movement.

[0003] When using the above-described hand lift stacker, operations such as the movement of the hand lifter, installation, movement of the pallet loaded with products, movement of the empty pallet, and installation occur, so the walking loss of the operator and the stop time of the equipment may become long, and a decrease in work efficiency becomes a problem.

[0004] Therefore, a trolley that enables loading and unloading and transportation of pallets without using a hand lifter may be used (see, for example, Patent Document 1). The trolley of this Patent Document 1 includes a trolley frame and a lift mechanism. The lift mechanism includes a front lift frame and a rear lift frame, a lift rod that connects the front and rear lift frames, and a lift link that is connected to the lift rod. The lift link is vertically extended and supported by the trolley frame. When the lift link is stepped down by a foot lever, the movement is transmitted to the front and rear lift frames via the lift rod, and the front and rear lift frames stand up. The pallet rises by the standing operation of the front and rear lift frames.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the trolley described in Patent Document 1 has a vertically extending lifting link operated by a foot lever, which necessitates securing space in the vertical direction for the installation of the lifting link. Therefore, if the space beneath the pallet is low-floor, the trolley cannot be advanced until the lifting link reaches beneath the pallet, and can only be advanced to the point where the lifting link is in front of the pallet. Consequently, the trolley protrudes significantly from the side of the pallet, requiring a wide aisle width and depth for transportation. This is a particular problem in factories and other places where space is limited.

[0007] Furthermore, while the lift mechanism in Patent Document 1 raises and lowers the front and rear lift frames via a lifting link and a lift rod, the lever ratio of the lifting link must be increased in order to lift heavy pallets. Increasing the lever ratio of the lifting link increases the installation space for the lifting link on the trolley. The larger the installation space for the lifting link, the longer the trolley protrudes from the side of the pallet, making the aforementioned problem even more pronounced. For this reason, it is difficult to lift heavy pallets with Patent Document 1.

[0008] This disclosure is made in view of the above points, and its purpose is to enable the lifting mechanism to reach under the pallet even if the space beneath the pallet is low-floor, and to enable heavy pallets to be lifted easily by human power. [Means for solving the problem]

[0009] To achieve the above objective, one aspect of the present disclosure may be based on a wheeled transport device for transporting pallets. The transport device comprises a frame formed to be able to enter beneath the pallet and to which the casters are attached, a lifting link mechanism disposed at multiple locations on the frame in a plan view, a drive mechanism for driving the lifting link mechanism, and a foot pedal supported so as to be able to swing around a horizontal axis relative to the frame and for inputting driving force to the drive mechanism.

[0010] The lifting link mechanism comprises a driven link, one end of which is rotatably connected to the frame around a horizontal axis, and a drive link, one end of which is rotatably connected to the other end of the driven link around a horizontal axis. By pulling the other end of the drive link toward the one end of the driven link, the mechanism is configured to form a triangular shape that protrudes upward in a side view.

[0011] The drive mechanism includes a rotating member supported so as to be rotatable around a pivot axis extending vertically between a plurality of lifting link mechanisms in the frame in a plan view, a flexible traction member connected to the side of the rotating member closer to the pivot axis than the outermost part of the rotating member and the other end of the drive link, and a conversion mechanism that converts rotational force around a horizontal axis input by the swinging of the foot pedal into rotational force around an axis extending vertically, and is configured to input the rotational force converted by the conversion mechanism to the radially outward side of the portion of the rotating member to which the traction member is connected.

[0012] In this configuration, when an operator presses the foot pedal, causing it to swing, rotational force around the horizontal axis is input to the conversion mechanism. The conversion mechanism converts the input rotational force around the horizontal axis into rotational force around an axis extending in the vertical direction and outputs it. The rotational force converted by the conversion mechanism is input to the radially outer side of the rotating member, causing the rotating member to rotate around the rotation axis extending in the vertical direction. This rotation of the rotating member causes the traction member to be wound and pulled, so that the other end of the drive link of the lifting link mechanism is pulled in a direction that approaches one end of the driven link. As a result, the lifting link mechanism takes on a triangular shape that protrudes upward when viewed from the side, causing the pallet located above it to rise.

[0013] The rotating member that constitutes the drive mechanism for driving the lifting link mechanism can pull the traction member by rotating around a pivot axis that extends in the vertical direction, so the vertical dimension can be short. Therefore, even if the space beneath the pallet is low-floor, the lifting mechanism can be brought under the pallet.

[0014] Furthermore, the rotational force generated by the operator's foot pedal is input radially outward from the portion of the rotating member to which the traction member is connected. This lever ratio setting makes it possible to lift heavy pallets. In other words, in this embodiment, increasing the lever ratio requires increasing the diameter of the rotating member, but even if the diameter of the rotating member is increased, only the horizontal dimension is expanded and the vertical dimension remains unchanged, so it does not hinder entry into low-floor spaces.

[0015] The conversion mechanism may include a pinion gear that rotates around a horizontal axis due to the swinging of the foot pedal, a rack that is slidably positioned horizontally below the pinion gear and extends in the sliding direction, with a first tooth formed on its upper surface that meshes with the pinion gear and a second tooth formed on its side, and an input gear that is rotatably supported on the side of the rack around an axis extending vertically and meshes with the second tooth. In this case, the drive mechanism can input the rotational force of the input gear to a point radially outward from the portion of the rotating member to which the traction member is connected. That is, it is possible to convert rotational force around a horizontal axis into rotational force around an axis extending vertically, while using a simple structure with a pinion gear and a rack.

[0016] The drive mechanism may be supported so as to be rotatable around an axis extending in the vertical direction and arranged to mesh with the input gear, and may have a speed-increasing gear that increases the rotational speed of the input gear. In this case, the rotational force of the speed-increasing gear can be input to a point radially outward from the portion of the rotating member to which the traction member is connected. That is, by interposing a speed-increasing gear, the rotational speed of the rotating member can be increased. As a result, even with a small amount of foot pedal operation, the amount of movement of the traction member can be increased to obtain the desired lifting height.

[0017] The drive mechanism may include a driven member that is rotatably supported around an axis extending in the vertical direction and driven by the rotational force of the speed-increasing gear, and a flexible power transmission member that is connected radially outward from the portion of the rotatable member to which the driven member and the traction member are connected.

[0018] The rotating member may include a first rotating body and a second rotating body arranged coaxially and coupled to each other. In this case, the traction member can be connected to the first rotating body and the other end of the drive link, and the power transmission member can be connected to the driven member and the second rotating body.

[0019] The frame may be rectangular in plan view. In this case, the lifting link mechanism includes first to fourth lifting link mechanisms respectively disposed at the four corners of the frame in plan view. Further, the traction member may include a first traction member whose one end is connected to the other end of the drive link of the first lifting link mechanism, a second traction member whose one end is connected to the other end of the drive link of the second lifting link mechanism, a third traction member whose one end is connected to the other end of the drive link of the third lifting link mechanism, and a fourth traction member whose one end is connected to the other end of the drive link of the fourth lifting link mechanism. The other ends of the first to fourth traction members can be connected to portions that are circumferentially separated from each other with respect to the rotating member.

[0020] The carrier may further include an anti-back mechanism that repeats locking and unlocking of the lifting link mechanism in the raised state in response to the stepping operation of the foot pedal. According to this configuration, the lifting link mechanism is automatically locked in the raised state only by the operator stepping on the foot pedal, so there is no need to perform a separate locking operation. Then, by further stepping on the foot pedal from the locked state, the lock is automatically released. Therefore, the operability of locking and unlocking is improved.

Effects of the Invention

[0021] As described above, even if the space under the pallet is a low floor space, a mechanism for lifting can enter under the pallet, and a heavy pallet can be lifted manually without difficulty.

Brief Description of the Drawings

[0022] [Figure 1] FIG. 1 is a plan view of a carrier according to an embodiment of the present invention. [Figure 2] FIG. 2 is a front view of a carrier according to an embodiment of the present invention. [Figure 3] FIG. 3 is a perspective view for explaining the use of the carrier. [Figure 4]FIG. 4 is a plan view showing an enlarged lifting link mechanism in a fallen state. [Figure 5] FIG. 5 is a sectional view taken along the line V-V in FIG. 4. [Figure 6] FIG. 6 is a view corresponding to FIG. 5 showing the lifting link mechanism in an ascending state. [Figure 7] FIG. 7 is a perspective view schematically showing a foot pedal and a drive mechanism. [Figure 8] FIG. 8 is a schematic view for explaining the operation of the anti-back mechanism.

Embodiments for Carrying out the Invention

[0023] Hereinafter, embodiments of the present invention will be described in detail based on the drawings. It should be noted that the following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present invention, its applications, or its uses.

[0024] FIG. 1 is a plan view of a carrier 1 according to an embodiment of the present invention, and FIG. 2 is a front view of the carrier 1. The carrier 1 can be used, for example, in factories where various processing, treatment, assembly work, etc. are performed, or in warehouses where articles are stored and warehoused. As shown in FIG. 3, for example, in a factory, a pallet 100 in which a plurality of articles called workpieces are accommodated may be used. The pallet 100 shown in FIG. 3 is of a box type and is configured by combining, for example, mesh materials. The pallet 100 has a cubic shape or a rectangular parallelepiped shape, and the entire upper part is open, serving as an accommodation port and an extraction port for articles. Legs 101 (only three are shown in FIG. 3) are provided at the four corners of the lower part of the pallet 100. By providing the legs 101, the bottom of the pallet 100 is separated upward by a predetermined distance from the floor surface of a factory, a warehouse, or the like.

[0025] In this embodiment, the case where the pallet 100 is a low-profile type pallet will be described. In the case of a low-profile type pallet 100, the distance between the bottom and the floor surface is about 10 cm to 15 cm. When transporting such a low-profile type pallet 100, a thin transport device is required, such as the transport device 1 with casters 2 according to the embodiment of the present invention.

[0026] Furthermore, when goods are placed in the box-type pallet 100, the total weight may exceed 100 kg or even 200 kg, and depending on the materials of the goods, it may weigh even more. When transporting such heavy pallets, it is necessary to lift the pallet 100 using the transport device 1 so that the legs 101 are lifted off the floor. When lifting the legs 101 off the floor, it is sufficient to lift them by, for example, 20 mm to 30 mm.

[0027] As shown in Figures 1 and 2, the transport device 1 according to this embodiment comprises a frame 10 to which casters 2 are attached, four lifting link mechanisms 20A to 20D, and a drive mechanism 30 that drives the lifting link mechanisms 20A to 20D. Figure 3 shows the device with a cover member A attached, although this is not an essential component.

[0028] The frame 10 is formed to be able to enter under the pallet 100 and is a thin and highly rigid frame. In this description of the embodiment, the front, rear, left, and right sides are defined as shown in each figure. That is, the front side is the side that enters under the pallet 100, and the rear side is the side opposite to the direction of entry. Therefore, the transport device 1 can be moved forward to enter under the pallet 100, and the transport device 1, which is in the state of being under the pallet 100, can be moved backward to be removed from under the pallet 100. Also, the side located to the left when the transport device 1 is viewed from the rear is called the left side, and the side located to the right when the transport device 1 is viewed from the rear is called the right side. The left-right direction of the transport device 1 can also be called the width direction of the transport device 1. Note that the definitions of each direction of the transport device 1 are for the convenience of explanation and do not limit the present invention. For example, the direction of entry may be defined as the rear direction, and the left-right direction described above may be defined as the front-back direction.

[0029] The frame 10 has a main body composed of a front plate 11, a rear plate 12, a left plate 13, and a right plate 14. The main body of the frame 10 is rectangular in plan view. The front plate 11, rear plate 12, left plate 13, and right plate 14 are made of high-strength materials such as steel plates. The front plate 11 extends in the left-right and up-down directions at the front end of the transport device 1. The rear plate 12 extends in the left-right and up-down directions at the rear end of the transport device 1. The front plate 11 and the rear plate 12 are parallel to each other. The left-right dimensions of the front plate 11 and the rear plate 12 are not particularly limited, but are set in the range of 700 mm to 1000 mm.

[0030] The left-side plate 13 extends in the front-rear and up-down directions at the left end of the transport device 1, with its front end fixed to the front plate 11 by welding or the like, and its rear end fixed to the rear plate 12 by welding or the like. The right-side plate 14 extends in the front-rear and up-down directions at the right end of the transport device 1, with its front end fixed to the front plate 11 by welding or the like, and its rear end fixed to the rear plate 12 by welding or the like. The distance between the left-side plate 13 and the right-side plate 14 is narrower at the front than at the rear. This makes it less likely for the left and right ends of the transport device 1 to hit the legs 101 when the transport device 1 is moved between the legs 101 of the pallet 100. The left-side plate 13 and the right-side plate 14 may be parallel to each other.

[0031] The front-to-back dimensions of the left panel 13 and the right panel 14 are not particularly limited, but are set within a range of, for example, 700 mm to 1000 mm. In addition, the vertical dimensions of the front panel 11, rear panel 12, left panel 13, and right panel 14 are approximately 90 mm, which allows for a thin frame 10.

[0032] The left portion of the rear panel 12 extends further to the left than the left panel 13, and the right portion of the rear panel 12 extends further to the right than the right panel 14. The left and right portions of the rear panel 12 are contact points that come into contact with the legs 101 when the device is brought under the pallet 100. When moving the transport device 1 under the pallet 100, it is sufficient to move it until the contact points come into contact with the legs 101.

[0033] Three left-side mounting plates 13a are provided extending to the left from the front, rear, and intermediate portions in the front-to-back direction of the upper edge of the left-side plate material 13, to which casters 2 are attached. Casters 2 are attached to the underside of each left-side mounting plate 13a. The left sides of the three left-side mounting plates 13a are connected by a left-side member 13b that extends in the front-to-back direction.

[0034] Three right-side mounting plates 14a are provided extending to the right from the front, rear, and intermediate portions in the front-to-back direction of the upper edge of the right-side plate material 14, to which casters 2 are attached. Casters 2 are attached to the underside of each right-side mounting plate 14a. The right sides of the three right-side mounting plates 14a are connected by a right-side member 14b that extends in the front-to-back direction.

[0035] Each caster 2 is a caster that can pivot around a vertical axis, which allows the transport device 1 to move not only in a straight line but also in a curved line and to rotate in place, thus increasing the degree of freedom of movement. The number of left mounting plates 13a and right mounting plates 14a is not limited to three; there may be two or four. The number of left mounting plates 13a and right mounting plates 14a corresponds to the number of casters 2.

[0036] Inside the main body of the frame 10, a front bottom plate 15 and a rear bottom plate 16 are provided. The front bottom plate 15 extends in the left-right direction along the lower part of the rear surface of the front plate material 11, and also extends in the front-rear direction. Its left end is fixed to the lower part of the left plate material 13 by welding, etc., and its right end is fixed to the lower part of the right plate material 14 by welding, etc. The rear bottom plate 16 extends in the left-right direction along the lower part of the front surface of the rear plate material 12, and also extends in the front-rear direction. Its left end is fixed to the lower part of the left plate material 13 by welding, etc., and its right end is fixed to the lower part of the right plate material 14 by welding, etc. The front bottom plate 15 and the rear bottom plate 16 are located on the same plane near the bottom of the transport device 1.

[0037] A central vertical plate 17, which is elongated in the front-to-back direction, is provided in the left-to-right center of the main body of the frame 10. The central vertical plate 17 also extends in the left-to-right direction and is located on the same plane as the front bottom plate 15 and the rear bottom plate 16. The front end of the central vertical plate 17 is fixed to the left-to-right center of the front bottom plate 15 by welding or the like, and the rear end is fixed to the left-to-right center of the rear bottom plate 16 by welding or the like. In addition, a central horizontal plate 18, which is elongated in the left-to-right direction, is provided in the front-to-back center of the main body of the frame 10. The central horizontal plate 18 also extends in the front-to-back direction and is located on the same plane as the front bottom plate 15 and the rear bottom plate 16. The left end of the central horizontal plate 18 is fixed to the lower part of the front-to-back center of the left side plate material 13 by welding or the like, and the right end is fixed to the lower part of the front-to-back center of the right side plate material 14 by welding or the like.

[0038] A front connecting plate 10a, which is elongated in the left-right direction, is provided between the front bottom plate 15 and the central horizontal plate 18 inside the main body of the frame 10. The front connecting plate 10a also extends in the front-rear direction and is located on the same plane as the front bottom plate 15 and the rear bottom plate 16. The front connecting plate 10a is fixed to the front sides of the left panel 13, the central vertical plate 17, and the right panel 14, respectively, and connects the front sides of the left panel 13, the central vertical plate 17, and the right panel 14.

[0039] A rear connecting plate 10b, which is elongated in the left-right direction, is provided between the rear bottom plate 16 and the central horizontal plate 18 inside the main body of the frame 10. The rear connecting plate 10b also extends in the front-rear direction and is located on the same plane as the front bottom plate 15 and the rear bottom plate 16. The rear connecting plate 10b is fixed to the rear sides of the left panel 13, the central vertical plate 17, and the right panel 14, respectively, and connects the rear sides of the left panel 13, the central vertical plate 17, and the right panel 14.

[0040] A left-side connecting plate 10c, which is elongated in the front-to-back direction, is provided between the left-side plate 13 and the central vertical plate 17 inside the main body of the frame 10. The left-side connecting plate 10c also extends in the left-to-right direction and is located on the same plane as the front bottom plate 15 and the rear bottom plate 16. The left-side connecting plate 10c is fixed to the left side of the front bottom plate 15, the front connecting plate 10a, the central horizontal plate 18, the rear connecting plate 10b, and the rear bottom plate 16, respectively, and connects the left sides of the front bottom plate 15, the front connecting plate 10a, the central horizontal plate 18, the rear connecting plate 10b, and the rear bottom plate 16.

[0041] A right-side connecting plate 10d, which is elongated in the front-to-back direction, is provided between the right-side plate 14 and the central vertical plate 17 inside the main body of the frame 10. The right-side connecting plate 10d also extends in the left-to-right direction and is located on the same plane as the front bottom plate 15 and the rear bottom plate 16. The right-side connecting plate 10d is fixed to the right side of the front bottom plate 15, the front connecting plate 10a, the central horizontal plate 18, the rear connecting plate 10b, and the rear bottom plate 16, respectively, and connects the right sides of the front bottom plate 15, the front connecting plate 10a, the central horizontal plate 18, the rear connecting plate 10b, and the rear bottom plate 16.

[0042] The front bottom plate 15, rear bottom plate 16, central vertical plate 17, central horizontal plate 18, front connecting plate 10a, rear connecting plate 10b, left connecting plate 10c, and right connecting plate 10d are bottom components that form the bottom of the frame 10 inside the main body of the frame 10, and are arranged in a grid pattern and connected to each other, so these components can increase the strength and rigidity of the frame 10. In other words, the front bottom plate 15, rear bottom plate 16, central vertical plate 17, central horizontal plate 18, front connecting plate 10a, rear connecting plate 10b, left connecting plate 10c, and right connecting plate 10d are reinforcing members of the frame 10, and may also be components that form part of the frame 10. It is not necessary to provide all of the front bottom plate 15, rear bottom plate 16, central vertical plate 17, central horizontal plate 18, front connecting plate 10a, rear connecting plate 10b, left connecting plate 10c, and right connecting plate 10d, and some may be omitted. Furthermore, additional reinforcing members may be provided on the frame 10.

[0043] In this embodiment, the lifting link mechanism includes four lifting link mechanisms 20A to 20D, each positioned at one of the four corners of the frame 10 in a plan view. Specifically, the left front lifting link mechanism 20A (first lifting link mechanism) is positioned at the left front corner of the frame 10, the right front lifting link mechanism 20B (second lifting link mechanism) is positioned at the right front corner of the frame 10, the left rear lifting link mechanism 20C (third lifting link mechanism) is positioned at the left rear corner of the frame 10, and the right rear lifting link mechanism 20D (fourth lifting link mechanism) is positioned at the right rear corner of the frame 10. In this way, the four lifting link mechanisms 20A to 20D are positioned so as to avoid the center of the frame 10 and are spaced apart from each other, allowing the pallet 100 to be raised stably. In this embodiment, the lifting link mechanisms 20A to 20D are arranged at each of the four corners of the frame 10, but this is not limited to this configuration. Three or fewer lifting link mechanisms may be arranged at intervals from each other, or five or more lifting link mechanisms may be arranged at intervals from each other. The placement of the lifting link mechanisms is not limited to the corners of the frame 10, but may also be in a position closer to the center. In other words, the lifting link mechanisms can be arranged at multiple locations on the frame 10 in a plan view.

[0044] The four lifting link mechanisms 20A to 20D all have the same structure. The left front lifting link mechanism 20A and the right front lifting link mechanism 20B have a symmetrical structure in the left-right direction, the left rear lifting link mechanism 20C and the right rear lifting link mechanism 20D have a symmetrical structure in the left-right direction, the left front lifting link mechanism 20A and the left rear lifting link mechanism 20C have a symmetrical structure in the front-rear direction, and the right front lifting link mechanism 20B and the right rear lifting link mechanism 20D have a symmetrical structure in the front-rear direction.

[0045] The details of the left front lifting link mechanism 20A are described below. Figures 4 and 5 show the left front lifting link mechanism 20A in a lowered state (also called a lowered state). In Figure 5, dashed lines show the plate material 102 interposed between the left front lifting link mechanism 20A and the pallet 100, and the left connecting plate 10c and front bottom plate 15 provided at the bottom of the frame 10, respectively, so that the positions of the plate material 102, the left connecting plate 10c, and the front bottom plate 15 relative to the left front lifting link mechanism 20A can be seen. Figure 6 shows the left front lifting link mechanism 20A in an elevated state.

[0046] The left front lifting link mechanism 20A is positioned directly above the left connecting plate 10c and the front bottom plate 15, and includes a pair of left and right driven links 21, a pair of left and right drive links 22, a roller 23, and an input member 24. The frame 10 has support members 25 for supporting the driven links 21 and the drive links 22, and the support members 25 are fixed to the main body portion of the frame 10.

[0047] The support member 25 includes a left support member 25a extending in the front-rear direction on the left side of the left front lifting link mechanism 20A, a right support member 25b extending in the front-rear direction on the right side of the left front lifting link mechanism 20A, and a front support member 25c extending in the left-right direction on the front side of the left front lifting link mechanism 20A.

[0048] The left-side driven link 21 is positioned to extend in the front-rear direction. The rear end (one end) of the left-side driven link 21 is rotatably connected to the rear side of the left-side support member 25a via a horizontally extending driven-side connecting shaft (first horizontal shaft) 21a. The right-side driven link 21 is approximately parallel to the left-side driven link 21, is positioned to extend in the front-rear direction, and is located in a position that overlaps with the left-side driven link 21 in a side view. The rear end (one end) of the right-side driven link 21 is rotatably connected to the rear side of the right-side support member 25b via a horizontally extending driven-side connecting shaft (first horizontal shaft) 21b.

[0049] The left drive link 22 is positioned to the right of the left driven link 21 and extends in the front-rear direction. The rear end (one end) of the left drive link 22 is rotatably connected to the front end (other end) of the left driven link 21 around a drive-side connecting shaft (second horizontal shaft) 22a that extends horizontally. The right drive link 22 is approximately parallel to the left drive link 22 and is positioned to the left of the right driven link 21. Furthermore, this right drive link 22 extends in the front-rear direction and is positioned in a position that overlaps with the left drive link 22 in a side view. The rear end (one end) of the right drive link 22 is rotatably connected to the front end (other end) of the right driven link 21 around a drive-side connecting shaft (second horizontal shaft) 22b that extends horizontally.

[0050] In the lowered state shown in Figure 5, the front end of the driven link 21 is slightly higher than the rear end of the driven link 21, and the rear end of the drive link 22 is slightly higher than the front end of the drive link 22. By setting the angles of the driven link 21 and the drive link 22 in this lowered state, when a traction force is applied by the traction member 32A described later, the driven link 21 and the drive link 22 form a triangular shape that protrudes upward in a side view, as shown in Figure 6.

[0051] A support shaft 23a is provided at the front end (or other end) of the drive link 22, which rotatably supports the roller 23. The support shaft 23a extends in the left-right direction and is parallel to the driven-side connecting shaft 21b, etc. The roller 23 is positioned between the front ends of the left and right drive links 22 and has an outer diameter larger than the vertical dimension of the drive link 22. The outer circumferential surface of the roller 23 contacts the upper surface of the left connecting plate 10c and the upper surface of the front bottom plate 15, and rolls on these upper surfaces in the front-rear direction. At this time, since the outer diameter of the roller 23 is larger than the vertical dimension of the drive link 22, the drive link 22 does not slide against the upper surface of the left connecting plate 10c or the upper surface of the front bottom plate 15.

[0052] The input member 24 connects the traction member 32A (described later) to the front end of the drive link 22 and is a member for inputting the traction force from the traction member 32A to the front end of the drive link 22. Both the left and right sides of the input member 24 are formed to protrude forward and are arranged to sandwich the roller 23 in the axial direction. Support shafts 23a are inserted through both the left and right sides of the input member 24, thereby supporting the front side of the input member 24 so as to be rotatable with respect to the support shafts 23a. On the rear side of the input member 24, a connecting portion 24a is formed to protrude rearward, to which one end of the traction member 32A is connected. The connecting portion 24a is positioned between the left and right drive links 22. Alternatively, the input member 24 may be omitted, and the traction member 32A may be directly connected to the front end of the drive link 22.

[0053] As shown in Figure 5, when the traction member 32A is pulled backward in the downward position, a backward traction force is applied to the input member 24, causing the front ends of the roller 23 and drive link 22 to be pulled backward via the support shaft 23a. As a result, the left and right driven links 21 rotate upward around the driven-side connecting shafts 21a and 21b, and the left and right drive links 22 rotate around the drive-side connecting shafts 22a and 22b, forming a triangular shape with the driven links 21 and drive links 22 protruding upward, which allows the pallet 100 located above them to be raised.

[0054] As the driven link 21 and the drive link 22 rotate, the front end of the drive link 22 approaches the rear end of the driven link 21, causing the roller 23 to roll backward on the upper surface of the left connecting plate 10c and the upper surface of the front bottom plate 15. In short, the left front lifting link mechanism 20A is configured to form a triangular shape that protrudes upward in a side view by pulling the front end of the drive link 22 toward the rear end of the driven link 21.

[0055] When the input member 24 of the right front lifting link mechanism 20B shown in Figure 1 is pulled backward in the same way as the left front lifting link mechanism 20A, the driven link 21 and drive link 22 of the right front lifting link mechanism 20B form a triangular shape that protrudes upward in a side view. In the case of the left rear lifting link mechanism 20C and the right rear lifting link mechanism 20D, pulling the input member 24 forward causes the driven link 21 and drive link 22 to form a triangular shape that protrudes upward in a side view.

[0056] When the left front lifting link mechanism 20A, the right front lifting link mechanism 20B, the left rear lifting link mechanism 20C, and the right rear lifting link mechanism 20D are located directly below the bottom of the pallet 100, the pallet 100 rises as the driven link 21 and the drive link 22 rotate so as to protrude upward. On the other hand, when the traction force is removed from the left front lifting link mechanism 20A, the right front lifting link mechanism 20B, the left rear lifting link mechanism 20C, and the right rear lifting link mechanism 20D, which are in the raised position, the weight of the pallet 100, the weight of the driven link 21, and the weight of the drive link 22 cause the driven link 21 and the drive link 22 to rotate until they are in a nearly horizontal position and fall over. At this time, the roller 23 rolls forward on the upper surface of the left connecting plate 10c and the upper surface of the front bottom plate 15, enabling smooth operation.

[0057] The drive mechanism 30 is a mechanism for driving four lifting link mechanisms 20A to 20D by human power. The transport device 1 is equipped with a foot pedal 50 for inputting driving force to the drive mechanism 30. The foot pedal 50 is swingable around a horizontal axis. Figure 7 schematically shows the foot pedal 50 and the drive mechanism 30. As shown in Figure 7, an input shaft 50a extending in the left-right direction is fixed to the front of the foot pedal 50. The input shaft 50a is supported on the rear side of the frame 10 via a bearing member 51. The foot pedal 50 is always biased upward.

[0058] The drive mechanism 30 includes a rotating member 31, four traction members 32A to 32D, and a conversion mechanism 40 that converts rotational force around a horizontal axis input by the swinging of the foot pedal 50 into rotational force around an axis extending in the vertical direction. The rotating member 31 is supported so as to be rotatable around a pivot axis 31a that extends vertically between the lifting link mechanisms 20A to 20D in the frame 10 in a plan view. Specifically, the rotating member 31 includes a first rotating body 31b and a second rotating body 31c that are arranged coaxially and coupled to each other. Both the first rotating body 31b and the second rotating body 31c are made of disc members. The outer diameter of the first rotating body 31b is smaller than the outer diameter of the second rotating body 31c. In other words, since the second rotating body 31c has a larger outer diameter, the outermost part of the rotating member 31 is made up of the outer circumference of the second rotating body 31c. Furthermore, in this embodiment, the first rotating body 31b is integrated with the second rotating body 31c, positioned above it.

[0059] As shown in Figure 1, the rotating member 31 is positioned between the left front lifting link mechanism 20A and the right rear lifting link mechanism 20D, and between the right front lifting link mechanism 20B and the right rear lifting link mechanism 20D. In other words, since the four lifting link mechanisms 20A to 20D are each located at the four corners of the frame 10, space can be secured in the central part of the frame 10 for arranging the rotating member 31. By arranging the rotating member 31 in this space, the increase in the height dimension of the transport device 1 is suppressed.

[0060] The lower part of the pivot shaft 31a is supported at the point where the central vertical plate 17 and the central horizontal plate 18 intersect. The distance between the pivot shaft 31a and each of the four lifting link mechanisms 20A to 20D is set to be approximately equal.

[0061] In this embodiment, the traction members include a left front traction member (first traction member) 32A connected to the front end of the drive link 22 of the left front lifting link mechanism 20A via an input member 24, a right front traction member (second traction member) 32B connected to the front end of the drive link 22 of the right front lifting link mechanism 20B via an input member 24, a left rear traction member (third traction member) 32C connected to the rear end of the drive link 22 of the left rear lifting link mechanism 20C via an input member 24, and a right rear traction member (fourth traction member) 32D connected to the rear end of the drive link 22 of the right rear lifting link mechanism 20D via an input member 24. All four traction members 32A to 32D are made of the same material, and in this embodiment, they are made of roller chains. Note that the traction members 32A to 32D may be made of flexible material other than roller chains, for example, belts, wires, ropes, wire rods, etc.

[0062] The front end (one end) of the left front traction member 32A is connected to the connecting portion 24a of the input member 24 of the left front lifting link mechanism 20A. The rear end (other end) of the left front traction member 32A is connected to the first rotating body 31b. In this way, the left front traction member 32A is connected to the first rotating body 31b and also to the front end of the drive link 22 of the left front lifting link mechanism 20A via the input member 24. Since the first rotating body 31b has a smaller diameter than the second rotating body 31c, the rear end of the left front traction member 32A is connected to the side of the rotating member 31 that is closer to the pivot axis 31a than to the outermost part of the rotating member 31. In addition, the connecting portion 24a and the first rotating body 31b are positioned at the same height.

[0063] The front end (one end) of the right front traction member 32B is connected to the connecting portion 24a of the input member 24 of the right front lifting link mechanism 20B. The rear end (other end) of the right front traction member 32B is connected to a portion of the first rotating body 31b that is circumferentially separated from the connecting portion of the left front traction member 32A.

[0064] The rear end (one end) of the left rear traction member 32C is connected to the connecting portion 24a of the input member 24 of the left rear lifting link mechanism 20C. The front end (other end) of the left rear traction member 32C is connected to a portion of the first rotating body 31b that is circumferentially separated from the connecting portion of the left front traction member 32A and the right front traction member 32B.

[0065] The rear end (one end) of the right rear traction member 32D is connected to the connecting portion 24a of the input member 24 of the right rear lifting link mechanism 20D. The front end (other end) of the right rear traction member 32D is connected to a portion of the first rotating body 31b that is circumferentially separated from the connecting portions of the left front traction member 32A, the right front traction member 32B, and the left rear traction member 32C. In this way, the other ends of the traction members 32A to 32D are connected to portions that are circumferentially separated from each other relative to the rotating member 31, and in this embodiment, the other ends of the traction members 32A to 32D are connected at 90° intervals, that is, at equal intervals in the circumferential direction.

[0066] A left front sprocket 52A, which is supported so as to be rotatable around an axis extending vertically relative to the frame 10, engages with the middle portion of the left front towing member 32A. By providing this left front sprocket 52A, the left front towing member 32A can be made straight in the front-rear direction in front of the left front sprocket 52A.

[0067] A right front sprocket 52B, which is supported so as to be rotatable around an axis extending vertically relative to the frame 10, engages with the middle portion of the right front towing member 32B. By providing this right front sprocket 52B, the right front towing member 32B can be made straight in the front-rear direction in front of the right front sprocket 52B.

[0068] A left rear sprocket 52C, which is supported so as to be rotatable around an axis extending vertically relative to the frame 10, engages with the middle portion of the left rear traction member 32C. By providing this left rear sprocket 52C, the left rear traction member 32C can be made straight in the front-rear direction behind the left rear sprocket 52C.

[0069] A right rear sprocket 52D, which is supported so as to be rotatable around an axis extending vertically relative to the frame 10, engages with the middle portion of the right rear traction member 32D. By providing this right rear sprocket 52D, the right rear traction member 32D can be made straight in the front-rear direction behind the right rear sprocket 52D.

[0070] Furthermore, in the fallen state, the side of the traction members 32A to 32D closer to the rotating member 31 than the sprockets 52A to 52D extends in a straight line. As a result, as will be described later, the traction members 32A to 32D can be pulled simply by rotating the rotating member 31.

[0071] As shown in Figure 7, the conversion mechanism 40 includes a pinion gear 41 that rotates around a horizontal axis due to the swinging of the foot pedal 50, a rack 42, and an input gear 43. The pinion gear 41 is fixed to the right side of the input shaft 50a, which is the pivot shaft of the foot pedal 50. The pivot center of the pinion gear 41 and the swing center of the foot pedal 50 are located on the same horizontal line extending in the left-right direction.

[0072] The rack 42 is positioned horizontally in the front-rear direction below the pinion gear 41 and is slidable in the front-rear direction. The rack 42 is formed to extend in the front-rear direction (sliding direction). The lower and right sides of the rack 42 are supported by members constituting the frame 10. The rack 42 is supported by members constituting the frame 10, so it is only capable of sliding in the front-rear direction. In this embodiment, since the pinion gear 41 is offset to the right of the left-right center of the frame 10, the rack 42 is similarly offset to the right.

[0073] On the upper surface of the rack 42, multiple first teeth 42a are formed so as to be aligned in the front-to-back direction, with which the pinion gear 41 meshes. On the left side surface of the rack 42, multiple second teeth 42b are formed so as to be aligned in the front-to-back direction.

[0074] The input gear 43 is rotatably supported around a first shaft 43a extending vertically on the left side of the rack 42, and includes a lower gear 43b located below and an upper gear 43c located above. The lower gear 43b and the upper gear 43c are integrated and cannot rotate relative to each other. The lower side of the first shaft 43a is attached, for example, to a central vertical plate 17. The lower gear 43b is positioned to mesh with the second tooth 42b of the rack 42.

[0075] In other words, when the foot pedal 50 swings up and down, causing the pinion gear 41 to rotate around the horizontal axis, the rotational force of the pinion gear 41 causes the rack 42 to move linearly in the front-to-back direction. When the rack 42 moves linearly in the front-to-back direction, the lower gear 43b, which meshes with the second tooth 42b, rotates around the first shaft 43a, which extends in the vertical direction. This allows the rotational force around the horizontal axis to be converted into rotational force around the axis extending in the vertical direction.

[0076] The drive mechanism 30 has a speed-increasing gear 44 that increases the rotational speed of the input gear 43. The speed-increasing gear 44 is rotatably supported around a second shaft 44a that extends in the vertical direction. The lower side of the second shaft 44a is attached to, for example, a central vertical plate 17. The second shaft 44a is positioned behind and to the left of the first shaft 43a. The speed-increasing gear 44 has a larger diameter and more teeth than the upper gear 43c of the input gear 43, and is positioned to mesh with the upper gear 43c. The speed-increasing gear 44 may be provided as needed and may be omitted. Alternatively, a reduction gear may be provided instead of the speed-increasing gear 44, or a gear with a number of teeth that results in a reduction ratio (speed-increasing ratio) of 1:1 may be provided.

[0077] The drive mechanism 30 includes an output gear 45 and an output sprocket 46. The output gear 45 is rotatably supported around a third shaft 45a that extends in the vertical direction. The lower side of the third shaft 45a is attached to, for example, a rear connecting plate 10b. The third shaft 45a is positioned in front of and to the left of the second shaft 44a. The output gear 45 has the same diameter and number of teeth as the speed-increasing gear 44 and is positioned to mesh with the speed-increasing gear 44.

[0078] The output sprocket 46 is positioned below the output gear 45 and is integrated with the output gear 45, preventing relative rotation. Like the output gear 45, the output sprocket 46 is supported so as to be rotatable around the third shaft 45a. Therefore, the output sprocket 46 is a driven member driven by the rotational force of the speed-increasing gear 44. The height of the output sprocket 46 is the same as that of the second rotating body 31c. The outer diameter of the output sprocket 46 is smaller than the outer diameter of the second rotating body 31c.

[0079] As shown in Figure 1, the drive mechanism 30 has a flexible power transmission member 47. The power transmission member 47 is made of a roller chain. However, the power transmission member 47 may be made of a flexible material other than a roller chain, such as a belt, wire, rope, or wire rod.

[0080] One end (rear end) of the power transmission member 47 is connected to a part of the circumferential direction of the output sprocket 46. The other end (front end) of the power transmission member 47 is connected to a part of the circumferential direction of the outer circumference of the second rotating body 31c. The middle portion of the power transmission member 47 is wrapped around a part of the circumferential direction of the outer circumference of the output sprocket 46 and also around a part of the circumferential direction of the outer circumference of the second rotating body 31c. Teeth (the same teeth as the sprocket teeth) that the power transmission member 47 engages with are formed on the outer circumference of the second rotating body 31c, although these are not shown in the figure.

[0081] As described above, the power transmission member 47 is connected to the output sprocket 46 and the second rotating body 31c, so that the rotational force converted by the conversion mechanism 40 can be input to the second rotating body 31c. The outer circumference of the second rotating body 31c is located radially outward from the portion of the first rotating body 31b to which the traction members 32A to 32D are connected, so that the rotational force of the input gear 43, that is, the rotational force of the speed-increasing gear 44 which is rotationally driven by the input gear 43, can be input radially outward from the portion of the rotating member 31 to which the traction members 32A to 32D are connected.

[0082] As described above, when an operator steps on the foot pedal 50 and rotates the pinion gear 41 in the direction of arrow B, the rack 42 moves linearly in the direction of arrow C, and this movement of the rack 42 in the direction of arrow C causes the input gear 43 to rotate in the direction of arrow D. When the input gear 43 rotates in the direction of arrow D, the speed-increasing gear 44 rotates in the direction of arrow E, so the output gear 45 and the output sprocket 46 rotate in the direction of arrow F.

[0083] When the output sprocket 46 rotates in the direction of arrow F, the power transmission member 47 is wound onto the output sprocket 46, causing the rotating member 31 to rotate in the direction of arrow F shown in Figure 1. When the rotating member 31 rotates in the direction of arrow F, the four traction members 32A to 32D are pulled simultaneously, thereby simultaneously pulling the other ends of the drive links 22 of the four lifting link mechanisms 20A to 20D toward one end of the driven link 21. Therefore, the four lifting link mechanisms 20A to 20D can be raised simultaneously.

[0084] In this embodiment, by simply pressing the foot pedal 50 once, the four lifting link mechanisms 20A to 20D shown in Figure 5 can be raised to the raised state shown in Figure 6. The amount of lift by the lifting link mechanisms 20A to 20D can be arbitrarily set by setting the number of teeth of the pinion gear 41, input gear 43, speed-increasing gear 44, output gear 45 and output sprocket 46, as well as setting the diameter of the rotating member 31. In this embodiment, the amount of lift by the lifting link mechanisms 20A to 20D is set to 20 mm to 30 mm.

[0085] (Anti-back mechanism) The transport device 1 of this embodiment is equipped with an anti-back mechanism 80 that repeatedly locks the lifting link mechanisms 20A to 20D in the raised position and unlocks the lifting link mechanisms 20A to 20D in response to a foot pedal 50 being pressed. As shown in Figure 8, the anti-back mechanism 80 has a claw member 81 fixed to the outer circumference of the second rotating body 31c, a locking member 82 that engages with the claw member 81, and an operating member 83 that operates the locking member 82. The claw member 81 is provided so as to protrude radially outward from the outer circumference of the second rotating body 31c. The locking member 82 is supported so as to be rotatable around an axis 82a that extends vertically relative to the frame 10. The lower side of the axis 82a is fixed to a central horizontal plate 18 or the like. The operating member 83 is fixed to a portion of the outer circumference of the second rotating body 31c that is a predetermined distance away from the claw member 81 in the circumferential direction.

[0086] In the "locked state" shown in Figure 8, the foot pedal 50 is pressed down, causing the second moving body 31c to rotate and the lifting link mechanisms 20A to 20D to be in the raised position. When the lifting link mechanisms 20A to 20D are in the raised position, the weight of the pallet 100 pushes the lifting link mechanisms 20A to 20D in the tilting direction. As a result, a rotational force in the opposite direction (arrow H direction) to the rotation direction (arrow F direction) during the upward movement is constantly acting on the second moving body 31c. When the second moving body 31c attempts to rotate in the direction of arrow H, the claw member 81 contacts the locking member 82 from the direction of arrow H and locks into place. As a result, even when the foot is released from the foot pedal 50, the rotation of the second moving body 31c in the direction of arrow H is prevented, and the lifting link mechanisms 20A to 20D are held in the raised position.

[0087] When the operator presses the foot pedal 50 while the device is locked, the second moving body 31c rotates in the direction of arrow F, as shown in Figure 8 as "pedal press". When the second moving body 31c rotates in the direction of arrow F, the operating member 83 fixed to the second moving body 31c pushes the locking member 82, causing it to rotate around the shaft 82a, reversing the orientation of the locking member 82 and setting the locking member 82 to the unlocked position, as shown in Figure 8 as "reversal".

[0088] Then, when the worker takes their foot off the foot pedal 50, the locking member 82 is in an unlocked position, as shown in Figure 8 as "unlocked," and the claw member 81 is positioned so that it is not locked. As a result, the weight of the pallet 100 causes the second moving body 31c to rotate in the direction of arrow H, and the second moving body 31c rotates until the lifting link mechanism 20A~20D is in a collapsed state (shown in Figure 8 as "collapsed state").

[0089] Subsequently, when the operator presses the foot pedal 50 again, the second moving body 31c rotates in the direction of arrow F, and the lifting link mechanism 20A~20D rises. Even after the operator releases their foot from the foot pedal 50, the claw member 81 contacts the locking member 82 from the direction of arrow H and locks, holding the lifting link mechanism 20A~20D in the raised position. In this way, the system can be automatically switched from the locked state to the unlocked state and from the unlocked state to the locked state simply by pressing the foot pedal 50.

[0090] (Effects of the embodiment) As described above, according to the transport device 1 of this embodiment, after lowering the lifting link mechanisms 20A to 20D and then moving them under the pallet 100, pressing the foot pedal 50 causes the rotational force of the foot pedal 50 around its horizontal axis to be input to the conversion mechanism 40 and converted into rotational force around an axis extending in the vertical direction. The rotational force converted by the conversion mechanism 40 is input to the radially outward side of the rotating member 31, causing the rotating member 31 to rotate around a pivot axis 31a that extends in the vertical direction. This rotation of the rotating member 31 simultaneously pulls the four towing members 32A to 32D, causing the four lifting link mechanisms 20A to 20D to form a triangular shape protruding upward in a side view, i.e., in an elevated state. This allows the pallet 100 to be raised. By raising the pallet 100, the casters 2 of the transport device 1 can transport the pallet 100. Because caster 2 can rotate freely, pallet 100 can also be rotated in place.

[0091] The rotating member 31, which constitutes the drive mechanism 30 for driving the lifting link mechanisms 20A to 20D, can pull the traction members 32A to 32D by rotating around a pivot axis 31a that extends in the vertical direction, thus shortening the vertical dimension of the drive mechanism 30. Therefore, even if there is a low-floor space below the pallet 100, the lifting mechanism can be brought under the pallet 100.

[0092] Furthermore, the operator's force on the foot pedal 50 is applied radially outward from the portion of the rotating member 31 to which the traction members 32A to 32D are connected. This lever ratio setting makes it possible to lift heavy pallets 100. In other words, increasing the lever ratio requires increasing the diameter of the rotating member 31, but even if the diameter of the rotating member 31 is increased, only the horizontal dimension is expanded and the vertical dimension does not change, so it does not hinder entry into low-floor spaces.

[0093] Although not shown in the diagram, the rear of the transport device 1 may also be provided with a handle for the worker to grip. The handle can be detachably attached to the frame 10. When moving the transport device 1, the handle can be attached to the frame 10, and after moving the transport device 1, the handle can be removed from the frame 10 so that it does not get in the way.

[0094] The transport device 1 can also be moved by, for example, an electric transport vehicle. The electric transport vehicle is equipped with a drive motor and battery, etc., and is a vehicle that travels on a predetermined track. In this case, for example, a connecting part for connecting to the electric transport vehicle is provided at the front or rear of the frame 10. By connecting this connecting part to the electric transport vehicle, the transport device 1 can be pulled and moved by the electric transport vehicle. Multiple transport devices 1 can also be connected in series and moved by a single electric transport vehicle.

[0095] The embodiments described above are merely illustrative in all respects and should not be interpreted restrictively. Furthermore, any modifications or changes that fall within the equivalent scope of the claims are all within the scope of the present invention. [Industrial applicability]

[0096] As explained above, the transport device relating to this disclosure can be used, for example, when transporting heavy objects such as pallets. [Explanation of Symbols]

[0097] 1. Transport equipment 2 casters 10 frames 20A~20D 1st~4th Lifting Link Mechanism 21. Driven Link 22 Drive link 30 Drive mechanism 31 Rotating Member 31b 1st rotation body 31c 2nd moving body 32A~32D 1st~4th traction members 40 Conversion mechanism 41 Pinion Gear 42 racks 42a First tooth 42b Second tooth 44 Speed-increasing gear 46 Output sprocket (driven component) 50 Foot pedals 80 Anti-back mechanism

Claims

1. A transport device with casters for transporting pallets, A frame formed to allow access under the pallet and to which the casters are attached, Lifting link mechanisms are arranged at multiple locations on the frame in a plan view, A drive mechanism that drives the aforementioned lifting link mechanism, The frame is supported so as to be able to swing about a horizontal axis, and a foot pedal is provided for inputting driving force to the drive mechanism. The lifting link mechanism comprises a driven link, one end of which is rotatably connected to the frame around a horizontal axis, and a drive link, one end of which is rotatably connected to the other end of the driven link around a horizontal axis. By pulling the other end of the drive link toward the one end of the driven link, it is configured to form a triangular shape that protrudes upward in a side view. The drive mechanism comprises a rotating member supported to rotate around a pivot axis extending vertically between a plurality of lifting link mechanisms in the frame in a plan view; a flexible traction member connected to the side of the rotating member closer to the pivot axis than the outermost part of the rotating member and to the other end of the drive link; and a conversion mechanism that converts rotational force around a horizontal axis input by the swinging of the foot pedal into rotational force around an axis extending vertically, and inputs the rotational force converted by the conversion mechanism to the radially outward side of the portion of the rotating member to which the traction member is connected.

2. In the transport device described in claim 1, The conversion mechanism includes a pinion gear that rotates around a horizontal axis by the swinging of the foot pedal, a rack that is slidably positioned horizontally below the pinion gear and extends in the sliding direction, with a first tooth formed on its upper surface that meshes with the pinion gear and a second tooth formed on its side surface, and an input gear that is rotatably supported on the side of the rack around an axis extending vertically and meshes with the second tooth. The drive mechanism is a transport device that inputs the rotational force of the input gear to a portion of the rotating member radially outward from the portion to which the traction member is connected.

3. In the transport device described in claim 2, The drive mechanism is supported so as to be rotatable around an axis extending in the vertical direction and is arranged to mesh with the input gear, and has a speed-increasing gear that increases the rotational speed of the input gear, and the rotational force of the speed-increasing gear is input radially outward from the portion of the rotating member to which the traction member is connected, in a transport device.

4. In the transport device described in claim 3, The drive mechanism comprises a driven member that is rotatably supported around an axis extending in the vertical direction and driven by the rotational force of the speed-increasing gear, and a flexible power transmission member connected radially outward from the portion of the rotatable member to which the driven member and the traction member are connected, in a transport device.

5. In the transport device described in claim 4, The rotating member includes a first rotating body and a second rotating body that are arranged coaxially and coupled to each other. The traction member is connected to the first rotating body and the other end of the drive link, The power transmission member is connected to the driven member and the second rotating body, and is part of a transport device.

6. In the transport device described in claim 1, The aforementioned frame has a rectangular shape when viewed from above. The aforementioned lifting link mechanism includes first to fourth lifting link mechanisms arranged at the four corners of the frame in a plan view, The traction member includes a first traction member, one end of which is connected to the other end of the drive link of the first lifting link mechanism; a second traction member, one end of which is connected to the other end of the drive link of the second lifting link mechanism; a third traction member, one end of which is connected to the other end of the drive link of the third lifting link mechanism; and a fourth traction member, one end of which is connected to the other end of the drive link of the fourth lifting link mechanism. A transport device in which the other ends of the first to fourth traction members are connected to the rotating member at portions that are circumferentially separated from each other.

7. In the transport device described in claim 1, A transport device further comprising an anti-back mechanism that repeatedly locks and unlocks the lifting link mechanism in the raised position in response to a pressing motion by the foot pedal.

Images