JP3919752B2 - Vehicle handling equipment - Google Patents

Description

  The present invention relates to an improvement of a vehicle handling apparatus having a loading platform for loading and unloading a load when loading and unloading the load, and more particularly, for example, tilting when an overload is applied to the tip of the loading platform. It relates to prevention measures.

  As a loading / unloading device for a vehicle, the loading platform base end is cantilevered by a parallel link mechanism, and the loading platform is moved up and down in a horizontal posture by the expansion and contraction of the hydraulic cylinder. 2. Description of the Related Art There is known a cargo handling device configured to tilt a front end downward and ground the tip. In such a cargo handling apparatus, when the upper end of the tilt arm is pivotally attached to the vehicle body fixed side as a component of the parallel link mechanism, for example, an overload is applied to the tip of the loading platform from above during the lifting and lowering of the loading platform. If the tilt arm is separated from the vehicle body fixing side, the loading platform tilts and cannot maintain the horizontal posture, and the load falls, which is very dangerous and hinders the cargo handling operation.

  By the way, as a type of loading / unloading apparatus that does not include a tilt arm, there is one that has taken a measure for preventing the loading platform from being tilted (see, for example, Patent Document 1). In this cargo handling device, a rotary side plate is pivotally attached to a rotary shaft that is rotated by an expansion and contraction operation of a hydraulic cylinder, a lift arm of a parallel link mechanism is pivotally attached to the rotary side plate, and a rod-like forced cam is attached to the rotary side plate. While being pivotally attached, a deterrent member is provided on the lift arm. The forced cam includes a first cam portion having a large radius of curvature, a second cam portion having a smaller radius of curvature than the first cam portion, and a linear portion continuously formed from one end side to the other end side, Either one of the first cam portion and the second cam portion slides on the support shaft of the upper tension arm according to the rotational posture of the rotary side plate, and the tip of the linear portion comes into contact with and separates from the restraining member. It has become. Then, when the loading platform is raised, the rotating side plate is rotated by the extension operation of the hydraulic cylinder, and the lift arm is supported and pushed up from below by the rotating side plate. At this time, the second cam portion of the forced cam is used as the support shaft of the tension arm. By sliding, the tip of the straight portion is pressed against the restraining member from above, and the loading platform is raised in a horizontal posture so as not to tilt. On the other hand, when the loading platform is lowered, the rotation side plate is rotated in the opposite direction by the contraction operation of the hydraulic cylinder, the lift arm is moved down following the rotation side plate, and the first cam portion of the forcible cam is brought into contact with the lift arm. Instead of the second cam part, the tip of the straight line part is detached from the restraining member by sliding on the support shaft of the tension arm, allowing the tip of the loading platform to tilt and allowing the tip of the loading platform to lean forward. ing.

On the other hand, as a type of cargo handling device provided with a tilt arm, there is one in which measures for preventing the loading platform from being tilted are taken (for example, see Patent Document 2). In this loading / unloading device, a hydraulic cylinder is newly incorporated in the parallel link mechanism separately from the hydraulic cylinder that lifts and lowers the loading platform so that the parallel state of the parallel link mechanism does not collapse when the loading platform moves up and down.
Japanese Utility Model Publication No. 63-23228 (page 2, FIG. 1, FIGS. 4 to 8) Japanese Patent No. 3035470 (pages 4 and 5, FIGS. 2 to 6)

  However, in the cargo handling device of Patent Document 1, in order to stably hold the loading platform in a horizontal position when ascending / descending, and tilting when contacting the ground, the shape of the first cam portion and the second cam portion of the forced cam is changed to the rotary side plate. It has to be formed with high precision in relation to the rotational movement of, and is difficult to manufacture. In addition, the cargo handling device of Patent Document 1 is a type that does not include a tilt arm, and in order to apply the cam mechanism to a cargo handling device that includes a tilt arm, it can be applied as it is because of restrictions on the installation space and differences in structure. It cannot be done, and even if it is installed, it must be remodeled.

  On the other hand, in the cargo handling device disclosed in Patent Document 2, the structure becomes complicated and the cost increases because the hydraulic cylinder is newly incorporated in the parallel link mechanism. In addition, since the hydraulic path between the hydraulic cylinder and the hydraulic cylinder that lifts and lowers the loading platform is connected to synchronize the hydraulic cylinders, the hydraulic path becomes complicated, and the complexity of the structure and the cost increase are promoted.

  The present invention has been made in view of the above points, and an object of the present invention is to make a cargo handling apparatus equipped with a tilt arm without significantly modifying the apparatus, and to complicate the structure and increase the cost. It is easy to prevent tilting during lifting of the loading platform.

  In order to achieve the above object, the present invention provides a structure for preventing the parallel link mechanism from moving by hooking the latching means on the vehicle body fixing side as a countermeasure against tilting of the loading platform of the cargo handling apparatus having a tilt arm. It is characterized by having adopted.

  Specifically, the present invention includes a loading platform for loading and lowering a load and two sets of parallel link mechanisms for cantilevering the loading platform base end, and each of the parallel link mechanisms has an upper end. A tilt arm pivotally attached to the vehicle body fixing side, a lift arm having one end near the top end of the tilt arm, and the other end pivotally attached to the loading platform base end, and a lower end of the lift arm. A lift cylinder having the other end pivotally attached to the lower end of the tilt arm, the lift cylinder extending and retracting the loading platform in a horizontal position between the ground and the vehicle body floor surface. When the loading platform is grounded in a horizontal position, the tilt arm is rotated in a direction away from the vehicle body fixing side and loaded. The platform tip is tilted to the forward descending intended for cargo apparatus for a vehicle configured to be grounded, it took solving means as follows.

That is, according to the first aspect of the present invention, a stopper is attached to the vehicle body fixing side, and a safety lever having a latching portion at one end is pivotally attached to the upper end side of the tilt arm. The latching portion is urged by the urging means so as to be latched by the stopper, and the one end of the lift arm is provided with the safety lever until the loading platform descends and approaches the ground or comes into contact with the ground. When the latching part is separated from the safety lever so as to be latched to the stopper by the biasing force of the biasing means and hold the locked state, when the loading platform descends and approaches the ground or is grounded, rotates in conjunction with the downward turning operation of the lift arm is pivoted abuts the safety lever to the safety lever disengaged the hook portion from the stopper It was characterized by joystick you unlock state is attached.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, the mounting position of the operating rod is variable according to the vehicle body floor surface height.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the operating rod includes a support shaft fixed to one end side of the lift arm, and a cylindrical body rotatably fitted on the support shaft. It is characterized by comprising.

  According to the invention according to claim 1, until the loading platform descends and approaches the ground or until it contacts the ground, the latching portion of the safety lever is latched on the stopper and is in a locked state. Even if a tensile force is applied to the tilt arm due to an overload applied to the tip of the loading platform, the safety lever does not move away from the vehicle body fixing side, so that the parallel state of the parallel link mechanism does not collapse, The platform is maintained in a horizontal position to prevent the cargo from falling, and the cargo handling operation is performed safely. On the other hand, when the loading platform descends and approaches the ground or touches the ground, the safety lever is rotated by the operating rod, and the locking part is released from the stopper to release the locked state. The loading platform assumes a forward leaning posture in a grounded state due to its own weight or a total load obtained by adding the load of the load.

  In this way, it is only necessary to engage and disengage the latching part of the safety lever with respect to the stopper, and it is not necessary to adopt a cam mechanism that requires high-precision machining or to make a major modification. There is no need to incorporate it into a mechanism or to synchronize with a hydraulic cylinder that raises and lowers the loading platform, and an inexpensive cargo handling device can be easily realized with a simple structure.

  According to the invention which concerns on Claim 2, one unit can be applied to the vehicle from which a vehicle body floor surface height differs, and it can be set as the cargo handling apparatus rich in versatility.

  According to the third aspect of the present invention, when the safety lever is pressed, the cylindrical body is slidably contacted while being rotated, so that wear of both the safety lever and the cylindrical body can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIGS. 6 to 9 show a cargo handling apparatus A installed under the floor at the rear end of a vehicle such as a truck. The cargo handling apparatus A includes a loading platform 1 that lifts and lowers a load, and two sets of parallel link mechanisms 2 that cantileverly support the left and right sides of the base end of the loading platform 1. These two sets of parallel links By the synchronous operation of the mechanism 2, the loading platform 1 is in the retracted state of FIG. 6, in the state of being at the vehicle body floor level in FIG. 7, in the state of being grounded in the horizontal posture of FIG. 8, and tilted at the tip of FIG. The posture is changed to each of the states.

  6-9, B1 is a vehicle body floor surface, B2 is a support frame of the closed cross-sectional shape which comprises the vehicle body fixed side extended in the vehicle width direction, This support frame B2 is extended in the vehicle body front-back direction at both vehicle width direction sides. It is fixed to a chassis frame (not shown) via a fixed bracket B3. A first support bracket B4 and a second support bracket B5 are disposed on the side of the fixed bracket B3 of the support frame B2.

  On the other hand, each parallel link mechanism 2 has a substantially cross-sectional shape with its upper end pivotally attached to the first support bracket B4 so as to be pivotable in the vertical direction as shown in FIGS. A character-shaped tilt arm 4 is provided. Near the upper end of the tilt arm 4, one end of a lift arm 5 is pivotally mounted on a shaft 6 so as to be pivotable in the vertical direction. The other end of the lift arm 5 is pivoted on the base end of the loading platform 1 with a shaft 7. It is pivotally attached so that it can rotate freely. A lift cylinder 8 made of a hydraulic cylinder is disposed below the lift arm 5, and one end (base end of the cylinder tube 8 a) of the lift cylinder 8 is pivoted to the lower end of the tilt arm 4 so as to be pivotable in the vertical direction. The other end (the tip of the piston rod 8b) is pivotally attached to the lift arm 5 near the tip of the lift arm 5 so as to be rotatable in the vertical direction. One end (cylinder tube 11a base end) of a tilt cylinder 11 made of a hydraulic cylinder is pivotally attached to the base end of the loading platform 1 so as to be pivotable in the vertical direction by a shaft 12, and the other end of the tilt cylinder 11 (piston) The rod 11b tip) is pivotally attached to the second support bracket B5 by a shaft 13 so as to be rotatable in the vertical direction.

  The tilt arm 4, the lift arm 5, the lift cylinder 8 and the tilt cylinder 11 constitute the parallel link mechanism 2. The lift cylinder 8 extends and retracts the loading platform 1 in a horizontal posture and the vehicle body floor surface in a horizontal posture. The height is raised and lowered (see FIGS. 7 and 8). The tilt cylinder 11 is adapted to change the posture of the loading platform 1 between the horizontal posture and the vertical posture at the height of the vehicle body floor by extending and contracting (see FIGS. 6 and 7). When the loading platform 1 is grounded in a horizontal posture, the tilt arm 4 is rotated about the axis 3 in the direction away from the support frame B2 by the weight of the loading platform 1 or by the total load obtained by adding the load of the load to this. By rotating, the tip of the loading platform 1 is tilted forward and lowered so as to be grounded (see FIGS. 8 and 9). That is, when the tilt arm 4 is rotated in the direction away from the support frame B2, the lift arm 5 is moved so as to be pushed out toward the front end side of the loading platform 1 by this rotation. It turns around and touches down in a forward leaning posture.

  As a feature of the present invention, a stopper 14 is attached to the upper surface of the support frame B2. On the other hand, on the upper end side of the tilt arm 4, a middle portion of a safety lever 15 having a claw-like hooking portion 15 a at one end is pivotally attached to a shaft 6 that pivotally attaches the lift arm 5 so as to be rotatable in the vertical direction. Yes. One end of a coil spring 16 as an urging means is connected to the other end of the safety lever 15, and the other end of the coil spring 16 is connected to an upright piece 17 erected on the lift arm 5. The lever 15 is urged by a coil spring 16 so that the hooking portion 15 a is hooked on the stopper 14. Note that a gap C (see FIG. 4) is formed between the latching portion 15a and the stopper 14, and this gap C is formed when the operating rod 18 rotates about the shaft 6. This is necessary to prevent interference with the stopper 14, and the loading platform 1 is slightly tilted by the load so that the gap C is eliminated and the locked state is maintained.

  An operating rod 18 is attached to one end side of the lift arm 5 (tilt arm 4 side) so as to face above the other end side of the safety lever 15 (side of the counter hooking portion 15a). The operating rod 18 includes a support shaft 19 that is fixed to one end side of the lift arm 5 so as to protrude laterally, and a cylindrical body 20 that is rotatably fitted to the support shaft 19. By replacing the support shaft 19 with the three mounting holes 5a formed on the side, the mounting position can be varied in the vertical direction according to the vehicle body floor surface height. In this example, the support shaft 19 is It is attached to the attachment hole 5a. When the loading platform 1 descends and approaches the ground G or contacts the ground, the operating rod 18 rotates the safety lever 15 by pressing the other end of the safety lever 15 from above to rotate the hooking portion 15a. It is configured to be released from the stopper 14 to release the locked state (see FIGS. 2, 5 and 8). As a result, the restraint state of the tilt arm 4 is released, and the loading platform 1 is allowed to tilt from the state of being grounded in the horizontal posture to the forward leaning posture.

  Next, the operation of the cargo handling apparatus A configured as described above will be described.

  (1) FIG. 6 shows a state in which the loading platform 1 is stored in a vertical posture. In this retracted state, the lift cylinder 8 and the tilt cylinder 11 are both extended, and the lift arm 5, the lift cylinder 8 and the tilt cylinder 11 are rotated upward to maintain an upwardly inclined posture toward the rear of the vehicle body. Yes. The safety lever 15 is pulled upward by the coil spring 16 so that the hooking portion 15a is hooked on the stopper 14 and is locked. Therefore, the tilt arm 4 is restricted and cannot be rotated.

  (2) To shift the loading platform 1 from the retracted state to the in-use state, the hydraulic pressure is discharged from the non-rod side working chamber of the tilt cylinder 11. As a result, the tilt cylinder 11 is contracted and the loading platform 1 is in a horizontal posture at the vehicle body floor height as shown in FIG. In this state, when unloading a load, the load is placed on the loading platform 1. The latching portion 15a of the safety lever 15 is in a locked state while being latched on the stopper 14. Therefore, during the operation of placing the load on the loading platform 1, even if a tensile force is applied to the tilt arm 4 due to, for example, an overload applied to the tip of the loading platform 1, the safety lever 15 is separated from the support frame B2. Therefore, the parallel state of the parallel link mechanism 2 does not collapse, the horizontal posture of the loading platform 1 is maintained, the falling of the load can be prevented, and the cargo handling operation can be performed safely.

  (3) Next, the hydraulic pressure is discharged from the non-rod side working chamber of the lift cylinder 8. As a result, the lift cylinder 8 contracts, the lift arm 5, the lift cylinder 8 and the tilt cylinder 11 rotate downward, and the loading platform 1 is lowered in a horizontal posture from the vehicle body floor surface height. During this time, since the latching portion 15a of the safety lever 15 remains locked on the stopper 14 and is in the locked state, the parallel state of the parallel link mechanism 2 does not collapse and descends in a horizontal posture without tilting the loading platform 1. It is possible to prevent the load from falling.

  (4) When the loading platform 1 descends and approaches the ground G, or when touching the ground in a horizontal posture as shown in FIG. 8, the operating rod 18 descends from above as the lift arm 5 rotates downward. Then, the other end of the safety lever 15 is pressed from above. As a result, the safety lever 15 rotates against the spring force of the coil spring 16, the latching portion 15a is detached from the stopper 14, the locked state is released, and the restraint state of the tilt arm 4 is released. At this time, since the cylindrical body 20 of the operating rod 18 is slidably brought into contact with the safety lever 15, wear of both the safety lever 15 and the cylindrical body 20 can be prevented. In this grounded state, the loading platform 1 rotates about the shaft 3 in a direction away from the support frame B2 by its own weight or a total load obtained by adding the load of the load to the support platform B2, and accordingly, the tilt arm 4 is supported by the support frame B2. When it rotates in the direction away from B2, the lift arm 5 moves so as to be pushed out to the tip side of the loading platform 1, and the parallel state of the parallel link mechanism 2 breaks down. Rotate around and ground in forward leaning posture. With this forward leaning posture, the luggage is unloaded or placed on the loading platform 1.

  (5) Next, when returning the loading platform 1 to the retracted state of the vertical posture or loading the load into the vehicle, hydraulic pressure is supplied to the anti-rod side working chamber of the lift cylinder 8. As a result, the lift cylinder 8 extends and the loading platform 1 rotates around the shaft 12 to return to the horizontal position shown in FIG. 8. Subsequently, the lift arm 5, lift cylinder 8 and tilt cylinder 11 are moved upward. It rotates and the loading platform 1 rises in a horizontal posture to the vehicle body floor height. When the loading platform 1 moves away from the ground G or ascends to a predetermined height from the ground G, the operating rod 18 moves away from the safety lever 15 as the lift arm 5 rotates upward, and the other end side of the safety lever 15 is By being pulled by the coil spring 16 and pivoting upward, the latching portion 15a is latched on the stopper 14 to be locked, and the safety lever 15 is restrained and cannot pivot. Therefore, even if a tensile force is applied to the tilt arm 4 due to an overload applied to the tip of the loading platform 1 ascending, the safety lever 15 does not move away from the support frame B2. The horizontal posture can be maintained to prevent the luggage from falling. Further, when the loading platform 1 is raised to the vehicle body floor height as shown in FIG. 7 and loads are loaded onto the vehicle or pulled out to the loading platform 1, the loading platform 1 is similarly maintained in the horizontal posture. Cargo handling work can be performed safely.

  (6) When the loading / unloading of the load is completed and the loading platform 1 is stored in the vertical posture from the horizontal posture in FIG. Then, the loading platform 1 may be rotated around the shaft 7 by extending the tilt cylinder 11 and rotating the loading platform 1.

  As described above, in this embodiment, since the latching portion 15a of the safety lever 15 only has to be hooked and detached with respect to the stopper 14, it is necessary to adopt a cam mechanism that requires high-precision machining or to make a major modification. In addition, there is no need to incorporate a hydraulic cylinder into the parallel link mechanism or to synchronize with the hydraulic cylinder that raises and lowers the loading platform, and an inexpensive cargo handling apparatus A can be easily realized.

  Moreover, in this embodiment, since the attachment position of the operating rod 18 can be changed in three stages, one cargo handling device A can be applied to a vehicle having a different vehicle body floor surface height. A rich cargo handling apparatus A can be obtained.

  In this embodiment, the cylinder tube 11a base end of the tilt cylinder 11 is pivotally attached to the loading platform 1 base end, and the piston rod 11b tip is pivotally attached to the second support bracket B5. In this case, the compression arm is pivotally attached to the base end of the loading platform 1 via the link.

  In this embodiment, the operating rod 18 is attached to one end side of the lift arm 5 (tilt arm 4 side) so as to face the upper side of the other end side of the safety lever 15 (reverse latching portion 15a side). On the other hand, the safety lever 15 is mounted so that it faces the other end side (counter latching portion 15a side), while a hook is attached to the lower surface of the other end of the safety lever 15 (counter latching portion 15a side). When the platform 1 descends and approaches the ground or comes into contact with the ground, the operating rod 18 is engaged with the hook and the other end of the safety lever 15 is pulled downward to rotate, and the latching portion 15a is moved from the stopper 14. The lock state may be released by detaching.

  Further, in this embodiment, the cargo handling apparatus A is applied to the rear end portion of the vehicle, but may be applied to the left end portion or the right end portion.

  INDUSTRIAL APPLICABILITY The present invention is useful as a vehicle loading / unloading device including a loading platform that loads and lifts a load when loading / unloading the load.

It is a perspective view of the vehicle body fixed side portion of the parallel link mechanism in the locked state. It is a perspective view of the vehicle body fixed side portion of the parallel link mechanism in the unlocked state. It is a top view of FIG. It is a side view of FIG. FIG. 3 is a side view of FIG. 2. It is a side view which shows the storage state of a loading platform. It is a side view which shows the state which has a loading platform in the vehicle body floor surface height. It is a side view which shows the state which the loading platform contact | grounded in the horizontal attitude | position. It is a side view which shows the state which inclined the loading platform front-end | tip and was earth | grounded.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Loading platform 2 Parallel link mechanism 4 Tilt arm 5 Lift arm 8 Lift cylinder 14 Stopper 15 Safety lever 15a Latching part 16 Coil spring (biasing means)
18 Control rod 19 Support shaft 20 Cylinder A Cargo handling device B1 Vehicle body floor B2 Support frame (vehicle body fixed side)
G ground

Claims (3)

A loading platform (1) for loading and lowering loads;
This loading platform (1) comprises two sets of parallel link mechanisms (2) that cantilever support the base end,
Each parallel link mechanism (2) includes a tilt arm (4) whose upper end is pivotally attached to the vehicle body fixing side (B2) ,
A lift arm (5) having one end pivoted toward the upper end of the tilt arm (4) and the other end pivotally attached to the base end of the loading platform (1) ;
A lift cylinder (8) disposed below the lift arm (5) , one end pivotally attached to the lower end of the tilt arm (4) and the other end pivotally attached to the tip of the lift arm (5) ;
The lift cylinder (8) lifts and lowers the loading platform (1) in a horizontal posture between the ground (G) and the vehicle body floor surface by an extension operation.
When the loading platform (1) is grounded in a horizontal position, the tilt arm (4) rotates in a direction away from the vehicle body fixing side (B2) to tilt the tip of the loading platform (1) forward and downward. A vehicle loading / unloading device configured to be grounded,
A stopper (14) is attached to the vehicle body fixing side (B2) ,
A safety lever (15) having a latching portion (15a) at one end is pivotally attached to the upper end side of the tilt arm (4) ,
The safety lever (15) is urged by the urging means (16) so that the hooking portion (15a) is hooked on the stopper (14) .
On the one end side of the lift arm (5 ), the latching portion (15a) of the safety lever (15) is provided until the loading platform (1) descends and approaches the ground (G) or is brought into contact with the ground. While being separated from the safety lever (15) so as to be locked on the stopper (14) by the urging force of the urging means (16), the loading platform (1) is lowered to the ground (G ) Approaching or grounding, it rotates in conjunction with the downward movement of the lift arm (5) and abuts on the safety lever (15) to rotate the safety lever (15) to engage the hook. cargo handling device for a vehicle, characterized in that the stop unit operation you unlock state by releasing the (15a) from the stopper (14) rod (18) is mounted. The vehicle cargo handling device according to claim 1,
A vehicle loading / unloading device characterized in that an operating position of the operating rod is variable depending on a vehicle body floor height. In the vehicle cargo handling apparatus according to claim 1 or 2,
The operating rod has a support shaft fixed to one end of the lift arm,
A vehicle loading / unloading apparatus comprising a cylindrical body rotatably fitted on the support shaft.

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