Loading platform lifting device

Abstract

To provide a loading platform lifting device that can easily correct a positional deviation to a load-carrying platform of an engagement object member of a lock mechanism.SOLUTION: A loading platform lifting device 10 includes: a loading platform 20 which rotates relative to a load-carrying platform of a vehicle, stands from a substantially horizontal state to a substantially vertical state, and moves up and down through lifting means; and a lock mechanism 100 which has an engagement member 150 that is attached to the loading platform 20 and an engagement object member 130 that is attached to the load-carrying platform 1 side by using bolts, and locks the loading platform 20 in a substantially vertical standing state by engaging the engagement member 150 with the engagement object member 130. The engagement object member 130 has bolt holes which are used when being attached to the load-carrying platform 1 side by using bolts, the bolt holes being long holes.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a platform lifting device. [Background technology]

[0002] A loading platform lifting device that is attached to the rear of a vehicle and raises and lowers the loading platform between the ground and the loading platform is equipped with a locking mechanism to keep the loading platform in an upright position when the loading platform is stored in an upright position while the vehicle is traveling. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-22208 [Patent Document 2] JP 2007-203906 A [Patent Document 3] JP 2014-101087 A Summary of the Invention [Problem to be solved by the invention]

[0004] The lock mechanism is composed of an engaged member fixed to the loading platform and an engaging member attached to the loading platform and engaged with the engaged member. Welding is generally used to fasten the engaged member to the loading platform. For example, in the loading platform lifting device of Cited Document 1, the engaged member (referred to as an "engaging piece" in Patent Document 1) is provided on the side gate of the loading platform, and the engaging member (referred to as a "rotating lever" in Patent Document 1) is provided on the side of the loading platform. In this case, welding is used to attach the engaged member to the side gate. In the loading platform lifting device of Patent Document 3, the engaged member (referred to as a "locked member" in Patent Document 3) is provided at the lateral end of the rear surface of the loading box, and the engaging member (referred to as a "slide bar" in Patent Document 3) is attached so as to be slidable in the width direction of the vehicle. In this case, welding is used to attach the engaged member to the loading box.

[0005] When the loading platform lifting device is attached to a vehicle, if the engaged member is fixed to the loading platform by welding, the engaged member may be fixed in a position where it cannot properly engage with the engaging member (hereinafter referred to as "misalignment during welding"). If misalignment occurs during welding, extra work such as redoing the welding of the engaged member or removing part of the engaged member will be required. In particular, when the loading platform lifting device is shipped as a product and then mounted on a truck vehicle at the destination, the engaged member will be attached by welding in this manner, which makes it more likely to misalign during welding.

[0006] In the loading platform lifting device of Patent Document 2, the hook, which is the engaged member, is fixed to the post, so that the hook is in a fixed relationship with the loading platform via the post, and the engaging member (referred to as a "lock handle" in Patent Document 2) is attached to the side of the loading platform. When the engaged member is attached to a member (post) of the loading platform lifting device fixed to the loading platform, as in Patent Document 2, instead of directly to the loading platform, the engaged member can be attached in a factory when assembling the loading platform lifting device. However, when the engaged member is attached to the member of the loading platform lifting device by welding and then the other parts are assembled, and the engaging member and the engaged member are engaged, the engaging member may not be able to engage with the engaged member properly due to various factors such as positional deviation during welding of the engaged member or assembly accuracy of the other parts. In this way, even if the engaged member is attached by welding in a factory, there are cases where the engaging member cannot be engaged with the engaged member properly, and work such as redoing welding of the engaged member of the lock mechanism or cutting off part of the engaging member is required.

[0007] SUMMARY OF THE PRESENT INVETION The present invention has been devised in view of the above-mentioned problems, and an object of the present invention is to provide a load-receiving platform lifting device that allows the position of an engaged member of a locking mechanism to be easily adjusted. [Means for solving the problem]

[0008] A first aspect of the present invention relates to a loading platform lifting device comprising a loading platform that rotates relative to the platform of a vehicle to rise from a substantially horizontal state to a substantially vertical state and is raised and lowered by a lifting means, an engaging member attached to the loading platform, and an engaged member attached to the platform side using a bolt, and a locking mechanism that locks the loading platform in a substantially vertical upright position by engaging the engaging member with the engaged member, in which the engaged member is provided with a bolt hole that is used when attaching it to the platform side using the bolt, and the bolt hole is a long hole.

[0009] With a load-receiving platform lifting device having such a configuration, the bolt holes used to attach the engaged member to the loading platform are long holes, so that it is possible to adjust the position of the engaged member even after the engaged member has been fixed to the loading platform. Even if a misalignment occurs between the engaged member and the engaging member, the positional relationship between the engaging member and the engaged member in the locking mechanism can be easily adjusted and corrected by simply loosening the bolt.

[0010] A loading platform lifting device according to a second aspect of the present invention comprises a loading platform which rotates relative to the platform of a vehicle to rise from a substantially horizontal state to a substantially vertical state and which is raised and lowered by a lifting means, an engaging member attached to the loading platform, a fixing member attached to the platform side, and an engaged member attached to the fixing member and with which the engaging member engages, and a locking mechanism which locks the loading platform in a substantially vertically raised state by engaging the engaging member with the engaged member, and the fixing member has an engaged member mounting portion to which the engaged member is attached, and a loading platform side mounting portion attached to the platform side. and the engaged member are formed integrally with each other perpendicularly, a first bolt hole is provided in the engaged member mounting portion of the fixing member, a second bolt hole is provided in the loading platform side mounting portion of the fixing member, and a third bolt hole is provided in the engaged member, the fixing member and the engaged member are fixed to each other by bolts inserted into the first bolt hole and the third bolt hole, the loading platform side mounting portion is fixed to the loading platform side by a bolt inserted into the second bolt hole, and any one or more of the first bolt hole, the second bolt hole and the third bolt hole is an elongated hole.

[0011] According to a load-receiving platform lifting device having such a configuration, since one or more of the first bolt hole, second bolt hole and third bolt hole are elongated holes, it is possible to adjust the position of the engaged member even after the engaged member has been fixed to the load-receiving platform via the fixing member, and even if a positional misalignment occurs between the engaged member and the engaging member, the positional relationship between the engaging member and the engaged member in the locking mechanism can be easily adjusted and corrected by simply loosening the bolt.

[0012] A load receiving platform lifting device according to a third aspect of the present invention is a load receiving platform lifting device according to the second aspect, wherein two or more of the first bolt hole, the second bolt hole and the third bolt hole are long holes, and the two or more long holes include a long hole whose longitudinal direction is the up-and-down direction of the vehicle and a long hole whose longitudinal direction is the fore-and-aft direction of the vehicle.

[0013] With a load-receiving platform lifting device having such a configuration, the position of the engaged member can be adjusted in two mutually perpendicular directions simply by loosening the bolt, making it possible to easily and more accurately adjust the positional relationship between the engaging member and the engaged member in the locking mechanism simply by loosening the bolt.

[0014] A load receiving platform lifting device according to a fourth aspect of the present invention is a load receiving platform lifting device according to the third aspect, wherein the first bolt hole, the second bolt hole and the third bolt hole are all long holes, and the three long holes are a long hole whose longitudinal direction is the up-and-down direction of the vehicle, a long hole whose longitudinal direction is the fore-and-aft direction of the vehicle, and a long hole whose longitudinal direction is the left-right direction of the vehicle.

[0015] With a load-receiving platform lifting device having such a configuration, it becomes possible to adjust the position of the engaged member in three directions perpendicular to the engaging member, and the positional relationship between the engaging member and the engaged member in the locking mechanism can be adjusted easily and more accurately by simply loosening the bolt.

[0016] A fifth aspect of the present invention is a loading platform lifting device according to any one of the second to fourth aspects, wherein the upper end of the engaged member is provided with a groove into which the engaging member engages, the engaging member is a lock handle having an engaging portion that fits into the groove and engages in the fore-and-aft direction of the vehicle, and when the loading platform is in an upright position, a first stopper portion that protrudes toward the side of the loading platform is formed on the surface of the engaged member facing the side of the loading platform, and the loading platform is formed with a first abutment portion that protrudes toward the engaged member and is positioned above the first stopper portion when the loading platform is in an upright position, and the first stopper portion and the first abutment portion are each positioned at a position such that when the loading platform is in an upright position, the gap dimension between the first abutment portion and the first stopper portion is smaller than the gap dimension between the groove portion of the engaged member and the lock handle.

[0017] With a load-receiving-platform lifting device having such a configuration, even if the lock handle is lowered together with the load receiving platform due to some reason (for example, leakage of pressurized oil in the hydraulic circuit device), the first stopper portion and the first abutment portion abut against each other before the lock handle hits the bottom of the groove of the engaged member, thereby preventing the lock handle from hitting the bottom of the groove of the engaged member. If the lock handle hits the bottom of the groove of the engaged member, it becomes difficult to rotate the lock handle, but the load-receiving-platform lifting device according to this aspect solves such a problem.

[0018] A sixth aspect of the present invention is a loading platform lifting device according to the fifth aspect, wherein when the loading platform is in an upright position, a second stopper portion is formed on the surface of the engaged member facing the side of the loading platform, the second stopper portion protruding toward the side of the loading platform, and when the loading platform is in an upright position, a second abutment portion is formed on the loading platform, the second abutment portion protruding toward the engaged member and being positioned rearward of the second stopper portion, and when the loading platform is in an upright position, the second abutment portion abuts against the second stopper portion, thereby regulating the upright angle of the loading platform, which rotates together with the second abutment portion, from a substantially horizontal position.

[0019] A loading platform lifting device having such a configuration eliminates the need for parts in addition to the locking mechanism that were used to regulate the limit of the loading platform's upright angle, resulting in a reduction in the number of parts and labor-saving installation work for the parts. Effect of the Invention

[0020] According to the present invention, it is possible to provide a load-receiving platform lifting device that allows the position of the engaged member of the locking mechanism to be easily adjusted. [Brief description of the drawings]

[0021] [Figure 1] 1 is a perspective view of a loading platform lifting and lowering device according to a first embodiment of the present invention. [Diagram 2] 1 is a side view of a load-receiving-table lifting device according to a first embodiment of the present invention, showing a load-receiving table in a stored state. [Diagram 3] 1 is a rear view of a load-receiving platform lifting and lowering device according to a first embodiment of the present invention. FIG. [Figure 4] FIG. 3 is an enlarged view of part A in FIG. 2. [Diagram 5] 5 is a cross-sectional view taken along line AA in FIG. 4. [Figure 6] 5 is a cross-sectional view of FIG. 4 taken along line B-B. [Figure 7] 2 is a perspective view of a fixing member and an engaged member of the load-receiving platform lifting and lowering device according to the first embodiment of the present invention. FIG. [Figure 8] FIG. 2 is a rear perspective view of an engaged member of the load-receiving platform lifting and lowering device according to the first embodiment of the present invention. [Figure 9] 2 is a perspective view of a portion of a locking mechanism of the load-receiving-table lifting and lowering device according to the first embodiment of the present invention; FIG. [Figure 10] FIG. 6 is a perspective view of a platform lifting and lowering device according to a second embodiment of the present invention. [Figure 11] FIG. 11 is a side view of a load-receiving-table lifting device according to a second embodiment of the present invention, showing the load-receiving table in a stored state. [Figure 12] FIG. 6 is a rear view of the load-receiving platform lifting and lowering device according to the second embodiment of the present invention. [Figure 13] 11 is a perspective view of a fixing member and an engaged member of a load-receiving platform lifting and lowering device according to a second embodiment of the present invention. FIG. [Figure 14] 11 is a perspective view of a portion of a locking mechanism of a load-receiving platform lifting and lowering device according to a second embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] First Embodiment Hereinafter, a loading platform lifting and lowering device 10 according to a first embodiment of the present invention will be described with reference to the drawings. In this specification, the front-rear, up-down, left-right directions are defined based on a truck vehicle (not shown) to which the loading platform lifting and lowering device 10 is attached.

[0023] As shown in Figures 1 and 2, the loading platform lifting device 10 is attached to the loading platform 1 of a truck vehicle (not shown). The loading platform lifting device 10 is composed of a loading platform 20, a parallel link mechanism, a locking mechanism 100, a hydraulic cylinder 40, a power unit 50, etc. The loading platform lifting device 10 is a device that raises and lowers the loading platform 20 using the parallel link mechanism and the hydraulic cylinder 40, which are lifting means, and locks the loading platform 20 in a substantially vertical upright position using the locking mechanism 100.

[0024] The parallel link mechanism is composed of a pillar 31, a first arm 32, a second arm 33, and an inter-arm connecting member 34. As shown in Fig. 3, the pillars 31 are arranged in a pair on the left and right in parallel with each other, and are erected on both sides of the rear end of the bed 1 of the truck vehicle. In other words, the pillars 31 are fixed to the truck vehicle side. The pillars 31 are support members that rotatably support the first arm 32 and the second arm 33. The pillar 31 is hollow, and the upper side is formed in a substantially square tube shape, and the lower side is formed in a substantially U-shaped cross section that opens rearward.

[0025] The first arms 32 are provided in a pair on the left and right. The base ends of the first arms 32 are rotatably connected to the inside of the pair of left and right columns 31. The second arms 33 are provided in a pair on the left and right at a position lower than the first arms 32. The base ends of the second arms 33 are rotatably connected to the inside of the pair of left and right columns 31.

[0026] A pair of inter-arm connecting members 34 are provided on the left and right, with their upper end sides rotatably connected to the tip side of first arm 32 via an axis member, and their lower end sides rotatably connected to the tip side of second arm 33 via an axis member. In this way, the support pillar 31, first arm 32, second arm 33 and inter-arm connecting members 34 form a parallel link mechanism.

[0027] The load receiving platform 20 has a base end rotatably connected to the inter-arm connecting member 34. The load receiving platform 20 is configured to be rotatable relative to the inter-arm connecting member 34 within a range from a substantially vertical standing state, which is a stored state, to a substantially horizontal state, which is a deployed state. As shown in Fig. 2, the hydraulic cylinder 40 is disposed inside the support column 31 in a state in which it extends in the height direction. The power unit 50 supplies and discharges hydraulic oil to the hydraulic cylinder 40 via piping (not shown).

[0028] The locking mechanisms 100 are arranged in a pair on the left and right sides of the loading platform 1, and as shown in Figures 4, 5 and 6, are composed of a fixing member 120 attached to the loading platform 1 side, an engaged member 130 attached to the fixing member 120 and engaged with an engaging member 150, and an engaging member 150 attached to the loading platform 20. However, if sufficient safety can be ensured with only one side, the locking mechanisms 100 can be omitted and only one on one side.

[0029] As shown in Figures 4, 5 and 6, the fixing member 120 is fixed to the bed 1 side via a support 31. The fixing member 120 has an engaged member attachment portion 121 to which the engaged member 130 is attached, and a bed-side attachment portion 122 that is attached to the bed 1 side. As shown in Figure 7, the fixing member 120 is integrally formed with a part of the engaged member attachment portion 121 and the bed-side attachment portion 122 perpendicular to each other.

[0030] The engaged member attachment portion 121 is provided with two first bolt holes 123 used when fixing the engaged member 130. The first bolt holes 123 are elongated holes with the longitudinal direction of the truck vehicle as the longitudinal direction. By making the first bolt holes 123 elongated holes with the longitudinal direction of the truck vehicle as the longitudinal direction, the engaged member 130 can be fixed while being adjusted in the longitudinal direction relative to the truck vehicle. In addition, a protrusion 124 protruding rearward is provided at the upper portion of the engaged member attachment portion 121.

[0031] In this embodiment, the bed side mounting portion 122 is attached to the support pillar 31 fixed to the bed 1 by a bolt 112. The bed side mounting portion 122 is provided with two second bolt holes 125. The second bolt holes 125 are elongated holes with the longitudinal direction being the left-right direction of the truck vehicle. The support pillar 31 is provided with a bolt hole (not shown) on the surface to which the bed side mounting portion 122 is attached, and a nut 111 is fixed by welding around the bolt hole on the inner surface of the support pillar 31. The fixing member 120 is attached and fixed to the support pillar 31 on the bed 1 side by inserting the bolt 112 into the second bolt hole 125 and the bolt hole of the support pillar 31 and screwing it into the nut 111. By making the second bolt hole 125 an elongated hole with the longitudinal direction being the left-right direction of the truck vehicle, the mounting position of the engaged member 130 with respect to the bed 1 can be adjusted in the left-right direction. The fixing member 120 does not need to be fixed directly to the loading platform 1 as in this embodiment, but may be fixed to the loading platform 1 via a component such as a support pillar 31.

[0032] As shown in Figs. 7 and 8, a groove 131 is provided at the upper end of the engaged member 130, into which the engaging member 150 is engaged. The groove 131 has a shape with an arc-shaped bottom and a width that widens toward the top, into which the engaging member 150 is inserted. The engaging member 150 inserted into the groove 131 is engaged in the front-rear direction of the vehicle. Furthermore, the engaged member 130 is provided with a third bolt hole 132 at a portion that abuts against the engaged member attachment portion 121 of the fixing member 120. The third bolt hole 132 is an elongated hole whose longitudinal direction is the vertical direction of the truck vehicle. By using such a third bolt hole 132, the vertical position of the engaged member 130 can be adjusted when the engaged member 130 is attached to the fixing member 120.

[0033] As shown in FIG. 9, the fixing member 120 and the engaged member 130 are fixed to each other by using a bolt 113 and a nut 114. The fixing member 120 is attached to the support 31 fixed to the bed 1 by the bolt 112, so that the engaged member 130 can be fixed to the bed 1. When the fixing member 120 is fixed to the support 31 by the bolt 112, a long hole (second bolt hole 125) whose longitudinal direction is the left-right direction of the truck vehicle is used, so that the fixing position of the engaged member 130 to the bed 1 can be adjusted in the left-right direction. Furthermore, when the fixing member 120 and the engaged member 130 are fixed to each other by the bolt, a long hole (first bolt hole 123) whose longitudinal direction is the front-rear direction of the truck vehicle and a long hole (third bolt hole 132) whose longitudinal direction is the up-down direction are used, so that the fixing position of the engaged member 130 to the fixing member 120 can be adjusted in the front-rear direction and the up-down direction. From the above, the loading platform lifting device 10 of this embodiment can adjust the position of the groove 131 with which the engaging member 150 engages in three mutually orthogonal directions, namely, front-rear, left-right, and up-down, relative to the truck vehicle. As a result, even if the engagement is insufficient when the fixing member 120 is fixed to the support 31 and the engaging member 150 is engaged with the engaged member 130, the position of the engaged member 130 can be easily and accurately adjusted by loosening the bolts 112, 113 and moving the fixing member 120 or the engaged member 130 so that the engaging member 150 can engage with the engaged member 130 in an appropriate state.

[0034] In this embodiment, the first bolt hole 123, the second bolt hole 125, and the third bolt hole 132 are all elongated holes. However, instead of making all of the first bolt hole, the second bolt hole, and the third bolt hole elongated, at least one bolt hole may be made elongated. For example, even if only one bolt hole is made elongated, it is possible to adjust the position of the engaged member relative to the engaging member. Furthermore, the longitudinal direction of the elongated hole is not limited to this embodiment, and for example, the longitudinal directions of the first bolt hole and the second bolt hole may be interchanged.

[0035] Furthermore, by making two bolt holes (for example, the first bolt hole and the third bolt hole) elongated, the position at which the engaged member is fixed to the fixing member can be adjusted in two directions, and thus the position of the engaged member can be adjusted in two directions. In this embodiment, the directions of the elongated holes of the first bolt hole 123, the second bolt hole 125, and the third bolt hole 132 are specified in three directions, respectively, but it is also possible to switch the directions of the elongated holes of the first bolt hole and the third bolt hole, for example. Which bolt hole is to be elongated and which direction the elongated hole is to be set in can be selected in consideration of the direction in which the engaged member and the engaging member are likely to be misaligned, depending on the configuration of the locking mechanism and the configuration of the loading platform lifting device, etc. Various modifications and combinations are possible as long as the position of the engaged member can be adjusted by using elongated holes.

[0036] In addition, in this embodiment, the fixing member 120 is used, but a configuration that does not use a fixing member is also possible. For example, a configuration in which the engaged member is directly fixed to the loading platform side with a bolt without using a fixing member is also possible. In this case, by making the bolt hole for fixing the engaged member to the loading platform side an elongated hole, the position of the engaged member relative to the loading platform can be easily adjusted, albeit in one direction, by loosening the bolt. In such a configuration in which a fixing member is not used, the shape of the engaged member can be changed to match the loading platform side to which it is fixed, and the direction of the elongated hole is not particularly limited, and the elongated hole may be in an appropriate direction according to various conditions.

[0037] In this embodiment, the engaged member 130 has a first stopper portion 133 and a second stopper portion 134 that protrude from a surface facing the load receiving platform 20 (the surface opposite to the surface that abuts against the fixed member 120) toward the side surface of the load receiving platform 20 when the load receiving platform 20 is in an upright state. The first stopper portion 133 and the second stopper portion 134 are connected by a curved surface to form a substantially L-shape. The first stopper portion 133 extends obliquely downward toward the rear from the connection portion with the second stopper portion 134, and the second stopper portion 134 extends vertically (upward) from the connection portion with the first stopper portion 133.

[0038] 9, in this embodiment, the engaging member 150 has a lock handle 151 made up of a support shaft 152 and a handle portion 153 as an operation portion connected to the support shaft 152 at a predetermined angle (almost a right angle in this embodiment). The lock handle 151 is formed by bending a round bar or the like into a substantially L-shape. The handle portion 153 of the lock handle 151 is attached so as to be freely rotatable about the support shaft 152 as a rotation axis.

[0039] A guide member 154 is provided around the support shaft 152 of the lock handle 151. The guide member 154 is fixed to the side of the load receiving platform 20 so as to protrude toward the engaged member 130 and be disposed above the first stopper portion 133 when the load receiving platform 20 is in an upright state. The support shaft 152 is guided by the guide member 154 and can advance and retreat in the width direction of the load receiving platform 20.

[0040] 6 and 7, a nut 155 is screwed onto the end of the shaft 152 at a portion located inside the load-receiving platform 20 (the side opposite the handle portion 153). A spring 156, through which the shaft 152 passes, is sandwiched between the nut 155 and the inner surface of the side surface of the load-receiving platform 20. The lock handle 151 is biased by the spring 156 in a direction that pulls the handle portion 153 toward the load-receiving platform 20.

[0041] The guide member 154 includes a cylindrical guide portion 154a and a U-shaped holding portion 154b. The support shaft 152 of the lock handle 151 is inserted into the inside of the guide portion 154a. The holding portion 154b is formed to include one end of the guide portion 154a, and an end of the holding portion 154b protrudes toward the engaged member 130 beyond the end of the guide portion 154a. In addition, the holding portion 154b forms a U-shape that opens in the same direction (upward) as the groove portion 131 of the engaged member 130 when the load receiving platform 20 is in an upright position that is a stored position.

[0042] When the load-receiving platform 20 is unlocked from a locked state in an upright position (a state in which the lock handle 151 is engaged with the groove portion 131), the tip side of the handle portion 153 is turned upward. When the tip side of the handle portion 153 is turned upward, the groove portion 131 and the holding portion 154b open in the same direction, so that the handle portion 153 enters the U-shaped groove of the holding portion 154b due to the biasing force of the spring 156, and as a result, the engagement between the lock handle 151 and the groove portion 131 is released. When the handle portion 153 enters the U-shaped groove of the holding portion 154b, the rotational movement of the handle portion 153 is restricted by the inner wall surface of the holding portion 154b.

[0043] On the other hand, when locking the loading platform 20 in the upright position, the loading platform 20 is rotated from a substantially horizontal position to an upright position, and the lock handle 151 is pulled out toward the engaged member 130 to rotate the handle portion 153 downward. As a result, the support shaft 152, which is the engagement portion of the lock handle 151, is inserted into the groove portion 131 of the engaged member 130 and engaged in the fore-and-aft direction of the truck vehicle, thereby locking the loading platform 20 in the upright position. When the handle portion 153 is rotated downward, it comes into contact with the protrusion 124 of the fixing member 120 and stops rotating.

[0044] When using the cargo receiving platform 20, as described above, the handle portion 153 is rotated upward to disengage the handle portion 153 from the groove portion 131, and then the lock handle 151 is moved horizontally toward the cargo receiving platform 20. This releases the lock and makes the cargo receiving platform 20 rotatable, so that the cargo receiving platform 20 can be deployed horizontally and raised and lowered by the hydraulic cylinder 40 during cargo handling work.

[0045] Since the loading platform lifting device 10 raises and lowers the loading platform 20 by the hydraulic cylinder 40, even when the loading platform 20 is locked in the upright position, the weight of the loading platform 20 and the like acts as a force that tends to extend the hydraulic cylinder 40. Normally, a check valve or the like provided in the hydraulic piping of the hydraulic circuit device for driving the hydraulic cylinder 40 prevents hydraulic oil from entering or leaving the hydraulic cylinder 40, so the hydraulic cylinder 40 is not extended by such a load.

[0046] However, if the loading platform 20 is not used for a certain period of time, the weight of the loading platform 20, etc. may cause a slight leak of pressure oil in the check valve, etc. If the hydraulic cylinder 40 expands due to the leak of pressure oil and the loading platform 20 in the upright state moves slightly in the unfolding direction (when the loading platform 20 is close to the upright state, the unfolding direction is approximately downward), and the lock handle 151 (support shaft 152) of the locking mechanism 100 abuts against the groove 131 of the engaged member 130, part of the weight of the lifting part of the loading platform 20, etc. is applied to the groove 131 via the lock handle 151. In this state, it becomes difficult to rotate the lock handle 151 due to the pressing force acting between the lock handle 151 and the groove 131, and there is a possibility that the lock by the locking mechanism 100 cannot be released smoothly.

[0047] In order to eliminate the pressing force acting between the lock handle 151 and the groove 131, in this embodiment, as shown in Fig. 8, a first stopper portion 133 is provided on the engaged member 130. The first stopper portion 133 is provided so as to prevent the lock handle 151 from abutting against the groove 131 by abutting against a holding portion 154b of a guide member 154 provided on the load receiving platform 20 before the lock handle 151 abuts against the groove 131, even if the hydraulic oil leaks from the hydraulic cylinder 40 when the load receiving platform 20 is in the upright state and the lock handle 151 moves slightly in the deployment direction together with the load receiving platform 20. In this specification, the portion where the holding portion 154b of the guide member 154 abuts against the first stopper is also referred to as a first abutment portion.

[0048] Therefore, in this embodiment, the first stopper portion 133 and the guide member 154 including the first abutment portion are positioned in an opposing positional relationship along the movement direction of the load receiving platform 20. When the load receiving platform 20 is in the upright state, the load receiving platform 20 is moved in the up and down direction by the hydraulic cylinder 40, so it is sufficient that the first stopper portion 133 is positioned directly below the first abutment portion of the guide member 154. In addition, the space dimension S2 between the lower surface of the first abutment portion of the guide member 154 and the upper surface of the first stopper portion 133 (i.e., the surfaces facing each other) is set to be smaller than the space dimension S1 between the groove portion 131 and the support shaft 152 of the lock handle 151 when the load receiving platform 20 is in the upright state. In addition, since the rotation of the load receiving platform 20 causes the holding portion 154b of the guide member 154 to rotate and move onto the first stopper portion 133, the first stopper portion 133 extends diagonally downward toward the rear in accordance with the trajectory of the holding portion 154b of the guide member 154. In this embodiment, the guide member 154 includes the first abutment portion, but a member other than the guide member 154 (a separate member that protrudes toward the engaged member 130 when the load receiving platform 20 is in the upright state and is fixed to the side portion of the load receiving platform 20 disposed above the first stopper portion 133) may be used as the first abutment portion.

[0049] In this embodiment, in order to regulate the angle of the receiving platform 20 from the substantially horizontal state, as shown in FIG. 8, the engaged member 130 is provided with a second stopper portion 134. The second stopper portion 134 is disposed at a position where the guide member 154 comes into contact when the receiving platform 20 rotates to the upright state. In other words, when the receiving platform 20 is in the upright state, the second stopper portion 134 is located in front of the guide member 154, and the front side surface of the guide member 154 is in a position where it comes into contact with the second stopper portion 134. By disposing the second stopper portion 134 in this manner, the guide member 154 rotates together with the receiving platform 20, and when the receiving platform 20 is in the upright state, the holding portion 154b of the guide member 154 comes into contact with the second stopper portion 134, and the receiving platform 20 is restricted from further rotating forward. In this specification, the portion where the holding portion 154b of the guide member 154 abuts against the second stopper portion 134 is also referred to as the second abutment portion. The second abutment portion may be any member fixed to the load receiving platform 20 so as to protrude toward the engaged member and be disposed behind the second stopper portion 134 when the load receiving platform 20 is in the upright state. It is also possible to provide a member other than the guide member 154 as the second abutment portion.

[0050] The effects achieved by providing the first stopper portion 133 and the second stopper portion 134 on the engaged member 130 can be summarized as follows.

[0051] In this embodiment, as shown in FIG. 6, when the loading platform 20 is in an upright position, the first stopper portion 133, which is in a fixed relationship with the loading platform 1, is disposed directly below the guide member 154, which is in a fixed relationship with the loading platform 20, with a gap dimension S2 smaller than the gap dimension S1 between the support shaft 152 of the lock handle 151 and the groove portion 131. By disposing the first stopper portion 133, even if the loading platform 20 in the upright position is lowered due to a leak of pressure oil or the like, the guide member 154, which is the first abutment portion, abuts against the first stopper portion 133 before the lock handle 151 contacts the groove portion 131. Therefore, it is possible to prevent an unnecessary force from acting between the lock handle 151 and the groove portion 131, and the lock handle 151 can be maintained in a free state. Therefore, in the loading platform lifting device of this embodiment, even if there is a leak of pressure oil in the hydraulic circuit device, the lock mechanism 100 can be easily operated to release the lock, so that the loading platform 20 can be used smoothly.

[0052] Furthermore, in this embodiment, as shown in FIG. 8, the engaged member 130 is provided with a second stopper portion 134 in addition to the first stopper portion 133. Conventionally, when the load receiving platform 20 is rotated to a substantially vertical standing state, a member for restricting the limit of the standing angle of the load receiving platform 20 is separately provided on the support or the like. In the configuration of the conventional lock mechanism, as described above, when the engaged member is attached, work such as cutting a part of the engaging member may be performed. Therefore, if a member for restricting the limit of the standing angle of the load receiving platform is attached to the engaged member in advance, the position of the member for restricting the limit of the standing angle must also be adjusted, and such a configuration could not be realized. However, as in the load receiving platform lifting device 10 of this embodiment, when the position adjustment of the engaged member 130 is easy, the load receiving platform 20 can be stopped at an appropriate position even if the engaged member is provided with the second stopper portion 134. In this way, by providing the second stopper portion 134 on the engaged member 130, the loading platform lifting device 10 of this embodiment eliminates the need for a member to regulate the limit of the upright angle of the loading platform 20, thereby achieving the effect of reducing the number of parts, etc.

[0053] In this embodiment, the first stopper portion 133 and the second stopper portion 134 are provided as one member, but it is also possible to provide only one of the stopper portions, or to provide the first stopper portion 133 and the second stopper portion 134 as two separate members. The first stopper portion 133 and the second stopper portion 134 can be selected as necessary, and various forms are possible. In addition, the guide member 154 is used as the first contact portion and the second contact portion, but it is also possible to use different members as the first contact portion and the second contact portion, or to use two different members as the first contact portion and the second contact portion, respectively.

[0054] The load-receiving platform lifting device 10 of this embodiment uses the fixing member 120 to attach the engaged member 130, and further uses bolts and elongated holes to assemble the engaged member 130 and the fixing member 120 and to fix the fixing member 120, thereby enabling the engaged member 130 to be positioned easily and accurately. Furthermore, by using the first stopper portion 133 and the second stopper portion 134, the lock can be released smoothly even if a leak of pressure oil occurs, and the member for restricting the limit of the erection angle of the load-receiving platform 20 can also be attached accurately.

[0055] Regarding the configuration of the loading platform lifting device, other than the locking mechanism 100, there are no particular limitations, and various configurations can be used for the parallel link mechanism, hydraulic cylinder, power unit, etc., and other configurations can also be added.

[0056] <Second embodiment> Next, the loading platform lifting device 10A according to the second embodiment will be described with reference to the drawings. As shown in Fig. 10, Fig. 11, and Fig. 12, the loading platform lifting device 10A according to the second embodiment does not use a member such as the support column 31 of the loading platform lifting device 10 according to the first embodiment, but is mounted below the loading platform 1A at a position that is the rear of the truck vehicle, and has a configuration in which the loading platform 20A is raised and lowered between the ground and the loading platform height by a parallel link mechanism and a hydraulic cylinder 40A. Furthermore, as shown in Fig. 10, the lock mechanism 100A of the loading platform lifting device 10A according to this embodiment is structured such that an engaging member 150A slides in the width direction of the truck vehicle by operating an engaging member operating device 158, and is engaged or disengaged with an engaged member 130A provided on the loading platform side.

[0057] The receiving platform lifting device 10A of this embodiment is a device that lifts and lowers the receiving platform 20A using a parallel link mechanism and a hydraulic cylinder 40A, which are lifting means, and locks the receiving platform 20A in a substantially vertical upright state using a lock mechanism 100A. The receiving platform lifting device 10A is composed of the receiving platform 20A, the parallel link mechanism, the lock mechanism 100A, the hydraulic cylinder 40A, a power unit, etc.

[0058] The parallel link mechanism is composed of a mounting member 35A, a first arm 32A, a second arm 33A, and an inter-arm connecting member 34A as shown in Fig. 11. The loading platform 1A is mounted on a pair of left and right body frames whose longitudinal direction is the front-to-rear direction of the truck vehicle, and mounting members 35A supporting a pair of left and right rotating arms (first arm 32A and second arm 33A) are connected to each of the body frames.

[0059] A pair of inter-arm connecting members 34A are provided on the left and right sides, with their upper end sides rotatably connected to the tip side of the first arm 32A via an axis member, and their lower end sides rotatably connected to the tip side of the second arm 33A via an axis member. In this manner, the mounting member 35A, the first arm 32A, the second arm 33A and the inter-arm connecting member 34A constitute a parallel link mechanism. The parallel link mechanism is driven by utilizing the expansion and contraction of a hydraulic cylinder 40A provided in the mounting member 35A.

[0060] The load receiving platform 20A has a base end rotatably connected to the inter-arm connecting member 34A. The load receiving platform 20A is configured to be rotatable with respect to the inter-arm connecting member 34A within a range from a substantially vertical standing state, which is a stored state, to a substantially horizontal state, which is an unfolded state.

[0061] As shown in Fig. 12, the locking mechanism 100A is arranged in a pair on the left and right sides of the loading platform 1A, and is composed of a fixing member 120A attached to the side wall 1a of the packing box, an engaged member 130A attached to the fixing member 210A and engaged with the engaging member 150A, and an engaging member operating device 158 provided on the loading platform 20A. When the loading platform 20A is in the upright state, the engaging member 150A is engaged with the engaged member 130A in a latch-like manner by manually operating the engaging member operating device 158. However, if sufficient safety can be ensured with only one side, the locking mechanism 100A can be omitted and only one on one side.

[0062] As shown in Fig. 12, the fixing member 120A is directly fixed to the side wall 1a of the packing box. The fixing member 120A has an engaged member attachment portion 121A and a loading platform side attachment portion 122A that is attached to the upper end surface of the side wall 1a of the packing box. As shown in Fig. 13, the engaged member attachment portion 121A and the loading platform side attachment portion 122A are connected perpendicular to each other, forming an L shape.

[0063] 13, engaged member attachment portion 121A is provided with first bolt hole 123A which is an elongated hole with its longitudinal direction aligned with the front-rear direction of the truck vehicle. By making first bolt hole 123A an elongated hole with its longitudinal direction aligned with the front-rear direction of the truck vehicle, when fixing member 120A and engaged member 130A with bolt 113A, the position of engaged member 130A can be adjusted in the front-rear direction relative to the truck vehicle while being fixed.

[0064] In this embodiment, the loading platform side mounting portion 122A is fixed to the rear end upper end surface of the side wall portion 1a of the loading box of the truck vehicle by using a bolt 112A. For this purpose, a bolt hole is provided in the rear end upper end surface of the side wall portion 1a of the loading box, and a nut is welded around the bolt hole. The loading platform side mounting portion 122A is provided with two second bolt holes 125A. The second bolt hole 125A is an elongated hole whose longitudinal direction is the left-right direction of the truck vehicle. The fixing member 120A is attached and fixed to the rear end upper end surface of the side wall portion 1a of the loading box by inserting the bolt 112A into the second bolt hole 125A and the bolt hole of the side wall portion 1a of the loading box and screwing it with the nut. By making the second bolt hole 125A an elongated hole whose longitudinal direction is the left-right direction of the truck vehicle, the position of the engaged member 130A relative to the loading platform 1A can be adjusted in the left-right direction of the truck vehicle.

[0065] The engaged member 130A is provided with a rectangular hole 135 into which the engaging member 150A engages. The engaging member 150A is inserted horizontally into the rectangular hole 135 and engaged in a latch-like manner. Furthermore, the engaged member 130A is provided with a third bolt hole 132A which is an elongated hole whose longitudinal direction is the vertical direction of the truck vehicle. By using the third bolt hole 132A, the position of the engaged member 130A can be adjusted in the vertical direction of the truck vehicle when the engaged member 130A is attached to the fixing member 120A.

[0066] As shown in Fig. 14, the fixing member 120A and the engaged member 130A are fastened to each other by a bolt 113A and a nut 114A. The fixing member 120A is attached directly to the side wall 1a of the packing box by using the bolt 112A. When the fixing member 120A is fixed to the side wall 1a of the packing box by the bolt 112A, the fixed position of the fixing member 120A to the side wall 1a of the packing box can be adjusted in the left-right direction of the truck vehicle by using a long hole (second bolt hole 125A) whose longitudinal direction is the left-right direction of the truck vehicle. This allows the position of the engaged member 130A fixed to the fixing member 120A relative to the truck vehicle to be adjusted in the left-right direction of the truck vehicle. Furthermore, when the fixing member 120A and the engaged member 130A are fixed using the bolt 113A and the nut 114A, the position at which the engaged member 130A is fixed to the fixing member 120A can be adjusted in the front-rear and up-down directions of the truck vehicle by using the long hole (first bolt hole 123A) whose longitudinal direction is the front-rear direction of the truck vehicle and the long hole (third bolt hole 132A) whose longitudinal direction is the up-down direction of the truck vehicle. From the above, the loading platform lifting device 10A of this embodiment can adjust the position of the rectangular hole 135 with which the engaging member 150A is engaged in the front-rear, left-right and up-down directions of the truck vehicle. As a result, even after the engaged member 130A is fixed to the loading platform 1A side, the positional relationship between the rectangular hole 135 and the engaging member 150A can be easily and accurately adjusted and corrected.

[0067] In this embodiment, the first bolt hole 123A, the second bolt hole 125A, and the third bolt hole 132A are all elongated holes, but it is not necessary for all of the first bolt hole, the second bolt hole, and the third bolt hole to be elongated holes, and at least one bolt hole can be a elongated hole. In addition, the direction of the elongated hole is not limited to this embodiment, and can be changed as appropriate depending on the number and arrangement of the elongated holes.

[0068] In addition, in this embodiment, the engaged member 130A is attached to the loading platform 1A side using the fixing member 120A, but the engaged member can be attached to the loading platform side (side wall 1a of the packing box) without using a fixing member. In this case, the bolt hole for fixing the engaged member to the loading platform side can be made into a long hole, so that the position of the engaged member relative to the loading platform side can be adjusted in one direction. It is also possible to integrate the fixing member and the engaged member into one engaged member. In this case, the bolt hole for fixing the fixed member to the loading platform side can be made into a long hole. When only the engaged member is used in this way, the bolt hole for fixing to the loading platform side can be made into a long hole, so that the engaged member can be adjusted in at least one direction.

[0069] As shown in FIG. 12, the engaging member 150A of this embodiment is a rod-shaped member made of iron with a rectangular cross section that extends in the width direction (left-right direction) of the truck vehicle and is provided so as to be slidable in the same direction. The engaging member 150A is disposed in a hollow portion of a panel member that constitutes the cargo receiving platform 20A. The engaging member 150A is linked to the operation of an engaging member operating device 158 provided on the cargo receiving platform 20A, and is in an engaged state (locked state) or disengaged state (unlocked state) with respect to the hole 135 of the engaged member 130A when the cargo receiving platform 20A is in an upright state. By operating the engaging member operating device 158, the two engaging members 150A slide left-right and in opposite directions to each other.

[0070] In the first and second embodiments, an arm-type load-receiving platform lifting device has been used, but a vertical load-receiving platform lifting device can also be used. In the case of a vertical load-receiving platform lifting device, this can be achieved by using a configuration in which an engaged member of a locking mechanism is attached to a support pillar, similar to the load-receiving platform lifting device 10 of the first embodiment. [Industrial Applicability]

[0071] The present invention can be applied to, for example, a loading platform lifting device. [Explanation of symbols]

[0072] 1,1A Cargo platform 1a Side wall of the packing box 10,10A Loading platform lifting device 20,20A loading platform 31 Post 32,32A First Arm 33,33A Second Arm 34, 34A Inter-arm connecting member 40,40A Hydraulic Cylinder 50 Power Unit 100,100A lock mechanism 120,120A Fixing member 121, 121A Engaged member mounting portion 122,122A Cargo bed side installation site 123,123A First bolt hole 124 Convex 125,125A 2nd bolt hole 130,130A Engaged member 131 Groove 132,132A 3rd bolt hole 133 First stopper part 134 Second stopper part 135 Rectangular Hole 150, 150A Engagement member 151 Lock handle 152 Spindle 153 Handle 154 Guide member 154a Guide part 154b Holding part 155 Nut 156 Spring 158 Engagement member operating device

Claims

1. a loading platform that rotates relative to the loading platform of the vehicle, rises from a substantially horizontal state to a substantially vertical state, and is raised and lowered by a lifting means; a locking mechanism that has an engaging member attached to the loading platform and an engaged member attached to the loading platform side by a bolt, and that locks the loading platform in a substantially vertical upright position by engaging the engaging member with the engaged member; In a load receiving platform lifting device comprising: The engaged member is provided with a bolt hole that is used when attaching the engaged member to the loading platform side using the bolt, The bolt hole is an elongated hole. A loading platform lifting device characterized by the above.

2. a loading platform that rotates relative to the loading platform of the vehicle, rises from a substantially horizontal state to a substantially vertical state, and is raised and lowered by a lifting means; a locking mechanism including an engaging member attached to the loading platform, a fixing member attached to the loading platform, and an engaged member attached to the fixing member and engaged with the engaging member, the locking mechanism locking the loading platform in a substantially vertical upright position by engaging the engaging member with the engaged member; In a load receiving platform lifting device comprising: The fixing member has an engaged member attachment portion to which the engaged member is attached and a loading platform side attachment portion to which the loading platform side is attached, the engaged member attachment portion being formed integrally with the loading platform side and perpendicular to each other, a first bolt hole is provided in the engaging member attachment portion of the fixing member, a second bolt hole is provided in the loading platform side attachment portion of the fixing member, and a third bolt hole is provided in the engaging member; the fixing member and the engaged member are fixed to each other by bolts inserted into the first bolt hole and the third bolt hole, The loading platform side mounting portion is fixed to the loading platform side by a bolt inserted into the second bolt hole, Any one or more of the first bolt hole, the second bolt hole, and the third bolt hole is an elongated hole. A loading platform lifting device characterized by the above.

3. The loading platform lifting device according to claim 2, any two or more of the first bolt hole, the second bolt hole, and the third bolt hole are elongated holes; The two or more elongated holes include an elongated hole whose longitudinal direction is the vertical direction of the vehicle and an elongated hole whose longitudinal direction is the front-rear direction of the vehicle. A loading platform lifting device characterized by the above.

4. The load receiving platform lifting device according to claim 3, the first bolt hole, the second bolt hole, and the third bolt hole are all elongated holes, The three long holes are a long hole whose longitudinal direction is the up-down direction of the vehicle, a long hole whose longitudinal direction is the front-rear direction of the vehicle, and a long hole whose longitudinal direction is the left-right direction of the vehicle. A loading platform lifting device characterized by the above.

5. The loading platform lifting device according to any one of claims 2 to 4, a groove portion into which the engaging member is engaged is provided at an upper end of the engaged member, the engaging member is a lock handle having an engaging portion that enters the groove and engages with the groove in the front-rear direction of the vehicle, When the load receiving platform is in an upright state, a first stopper portion is formed on a surface of the engaged member that faces a side surface of the load receiving platform, the first stopper portion protruding toward the side surface of the load receiving platform, a first contact portion is formed on the load receiving platform, the first contact portion being disposed above the first stopper portion and projecting toward the engaged member when the load receiving platform is in an upright state; the first stopper portion and the first abutment portion are disposed at positions such that a gap dimension between the first abutment portion and the first stopper portion is smaller than a gap dimension between the groove portion of the engaged member and the lock handle when the load receiving platform is in an upright state; A loading platform lifting device characterized by the above.

6. The loading platform lifting device according to claim 5, When the load receiving platform is in an upright state, a second stopper portion is formed on a surface of the engaged member that faces the side surface of the load receiving platform, the second stopper portion protruding toward the side surface of the load receiving platform, a second abutment portion is formed on the load receiving platform, the second abutment portion being disposed rearward of the second stopper portion and projecting toward the engaged member when the load receiving platform is in an upright state; When the second contact portion contacts the second stopper portion, the angle at which the load receiving platform rotates together with the second contact portion is restricted from a substantially horizontal state. A loading platform lifting device characterized by the above.

Images