JPH0446782B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a cargo handling vehicle, and more specifically, the present invention relates to a cargo handling vehicle, and more particularly, a front arm is provided that can maintain the attitude of a container detachably supported by a lift arm when the container is loaded onto or unloaded from a vehicle body. This relates to a cargo handling vehicle equipped with a cargo handling vehicle. [Prior Art] A cargo handling vehicle 1 that transports a container 3 shown in FIG.
A cargo handling device 2 for loading and unloading containers 3 onto and from the vehicle body is attached to the vehicle. In order to handle the container 3 with the device 2, it is necessary to support the container 3, and support shafts 4 are protruded from the left and right sides of the container 3. The cargo handling device 2 for receiving the support shaft 4 includes:
A pair of left and right lift arms 5 formed by a support portion 6 are provided, and are attached to the vehicle body 7 via a lift cylinder 8 and a support shaft 9 so as to be rotatable forward and backward. A rotatable front arm 10 is provided at the front central position of the vehicle body 7 to maintain the attitude of the container 3 during forward and backward rotation. The front arm 10 is formed, for example, in a dogleg shape, and a hook 11 (see FIG. 7) that can be opened and closed is attached to the top end portion 10a of the front arm 10.
4 can be grasped and released. The front arm 10 is attached to the vehicle body 7 via a support shaft 13 serving as a center of rotation, and is connected to an auxiliary cylinder 12 swingably attached to the vehicle body 7 by a pin shaft 30 at its lower end. The line connecting the support shafts 9 and 13 of the lift arm 5 and front arm 10 and the line connecting the posture support pin 14 and the support shaft 4 form two opposing sides of a parallelogram, and , a line connecting the support shaft 13 and the posture support pin 14, and a line connecting the support shaft 4 and the support shaft 9
The lines connecting the two sides form the other two sides of the parallelogram, so the lift arm 5 and the front arm 10
It can be tilted and rotated as one unit. Since the above-mentioned FIG. 1 includes the configuration of the present invention, the technology prior to the present invention will be explained below with reference to FIGS. 7 to 9. Tip portion 1 of the front arm 10 shown in FIG.
0a is provided with a fixed hook 11A having a recessed part, and a hook cylinder 11C for rotating the swinging hook 11B is attached to the upper part of the fixed hook 11A, and the swinging hook 11B for opening and closing the recessed part is attached to a pivot shaft. It is attached via 11D. Since the hook 11 supports the attitude support pin 14, when the front arm 10 rotates forward and backward together with the lift arm 5, the container 3 is held in a nearly horizontal attitude desirable for loading and unloading. [Problems to be Solved by the Invention] By the way, when the container 3 shown in FIG. 1 is loaded on the vehicle body 7 and the front arm 10 is in a forward-rotated position, its posture is slightly tilted toward the front of the vehicle body 7. At this time, the fixing hook 11A shown in FIG. 7 has its opening facing diagonally upward, and the posture support pin 14
is supported by the inner surface of the recess of the fixed hook 11A and the inner surface of the swinging hook 11B which closes the opening. If the contents of the container 3 (see Figure 1) are uneven, the center of gravity of the container 3 will move forward or backward,
The container 3 tilts forward or backward about the support shaft 4. When the container 3 is tilted backwards and upwardly forward, the posture support pin 14 is in the position shown by the two-dot chain line in FIG. 7, the hook 11 is pushed up, and the hook cylinder 1 in the extended state
exerts a force on 1C. However, since the distance between the line of action 15 of the thrust force W and the support shaft 11D is short as shown at 1 in the figure, the generated moment is small and the force exerted on the hook cylinder 11C is negligible. When the front arm 10 rotates backward by about half, the hook 11 assumes an attitude rotated approximately 90 degrees as shown in FIG. In this case, since the posture support pin 14 comes into contact with the recess of the fixing hook 11A as shown by the two-dot chain line, no force is exerted on the hook cylinder 11C. In such a posture, when the container 3 is tilted forward and downward, the posture support pin 14 is in a position as shown by the solid line and also comes into contact with the swing hook 11B. At this time, the distance between the line of action 15 of the pressing force by the posture support pin 14 and the vertical line passing through the support shaft 11D becomes the maximum value 2. The moment of rotation in the direction of arrow 16 around the support shaft 11D is maximum, and if the distance between the hook cylinder 11C and the support shaft 11D is 11, the following force acts on the hook cylinder 11C: F=W×2/11 . On the other hand, when the front arm 10 takes the backward position and holds the posture support pin 14 of the container 3 on the ground as shown in FIG. 9, when the container 3 is tilted forward, the posture support pin 14 The position shown by the solid line is such that a pressing force W is exerted on the swinging hook 11B. However, the line of action 15 of the pressing force and the support shaft 11
The distance from the vertical line passing through D is 3, which is shorter than the above-mentioned 2. Hook cylinder 1 in this case
The influence on 1C is relatively small as in FIG. As can be seen from the above behavior, posture support pin 1
4 applies a large force to the hook cylinder 11C at some point. In other cases, even if the force is small, it is necessary to determine the hydraulic pressure of the hook cylinder 11C in accordance with the large force. That is, there is a problem in that a hydraulic pressure higher than that required for opening and closing the swing hook 11B must be set, which is wasteful. As mentioned above, a hook mechanism for gripping the posture support pins of a container is described in Japanese Utility Model Application No. 61-82835. In this example as well, when the arm is tilted significantly backward to grab the attitude support pin of the container located on the ground with the hook, the attitude support pin is supported on the tip side of the swinging hook. Therefore, when lifting a container from the ground, a large moment acts on the swing hook. Therefore, a large hydraulic pressure that can counteract the moment is required in the cylinder that operates the swing hook. On the other hand, the arm is rotated as far as possible toward the rear of the vehicle in order to grab a container on the ground. but,
The arm assumes a “he” shape, and
The hook mechanism hooks the posture support pin from below. Therefore, it is necessary to tilt the arm greatly so that the hook mechanism is lower than the posture support pin, and at that time, the arm, which assumes a ``he''-shaped posture, can be used to tilt the arm from the rear window of the driver's seat. The view of the support pins is greatly obstructed. While looking at the rear from the driver's seat, you can move the vehicle backwards to bring the hook mechanism closer to the posture support pin.
In order to hook the swinging hook to the posture support pin,
Although detailed remote operation is required, there is a drawback that the engagement work at that time is significantly hindered. The present invention has been made to solve the above-mentioned problems, and its purpose is to maintain the container in a desired posture during loading and unloading, and to reduce the pressure in the hook cylinder that rotates the swinging hook. It is possible to reduce the capacity, avoid giving excessive rigidity to the swinging hook and make it smaller, and furthermore, it is possible to reduce the size of the swinging hook from the driver's seat when grabbing a container on the ground. To provide a cargo handling vehicle that can easily ensure visibility up to an engaging part and improve work efficiency. [Means for Solving the Problems] The present invention supports a removable container by a pair of lift arms provided on the left and right sides of a vehicle body,
It is applied to cargo handling vehicles that load and unload containers by swinging the lift arm forward and backward by the operation of the lift cylinder. Its characteristics are as shown in Figure 1.
In order to maintain the posture of the container 3 during loading and unloading, a posture support pin 1 is provided at the upper front end 3a of the container 3.
A front arm 10 supporting the vehicle body 4 is rotatably mounted on the vehicle body 7. A hook 19 for grasping the posture support pin 14 is provided at the tip of the front arm 10. The hook 19 is formed with a downwardly opened recess 20 (see FIG. 6) into which the attitude support pin 14 of the container 3 located on the ground can be inserted from approximately above. When grasping the fixing hook 19A that is located on the ground and the attitude support pin 14 of the container 3 located on the ground, the fixing hook 1 is rotated from approximately upward to downward.
A swinging hook 1 that closes the recess 20 of 9A and supports the posture support pin 14 in cooperation with the fixed hook 19A.
9B. On the other hand, the rotation center 19D of the swing hook 19B, which rotates due to the expansion and contraction of the hook cylinder 19C attached to the tip end portion 10a of the front arm 10, is close to the line of action 25 of the force applied to the swing hook 19B,
It is provided on the fixed hook 19A. [Operation] The container 3 loaded on the vehicle body 7 is supported by a pair of lift arms 5. On the other hand, a posture support pin 14 provided at the upper front end 3a of the container 3
is fitted into a recess 20 of a fixing hook 19A attached to the distal end portion 10a of the front arm 10. After the fitting, when the hook cylinder 19C is extended, the swinging hook 19B attached to the fixed hook 19A via a pivot serving as a rotation center 19D is rotated, and the recess 20 is closed. The posture support pin 14 is supported by a fixed hook 19A and a swing hook 19B. As a result, the container 3 is unloaded smoothly while always maintaining a horizontal attitude. When loading and unloading this container 3, when the front arm 10 rotates back and forth, the fixed hook 19
The posture support pin 14 fitted and supported in the recess 20 of A changes depending on the posture of the hook 19. Therefore, when the center of gravity of the container 3 is moving forward or backward, a pressing force and an upward force are applied to the swinging hook 19B via the posture support pin 14. However, since the fixed hook 19A is provided so that the rotation center 19D of the swinging hook 19B is close to the line of action 25 of the downward force and upward force applied to the posture support pin 14, The resulting moment can be kept small. Therefore, the force that causes the hook cylinder 19C to contract due to the generation of the moment is suppressed, and the hydraulic pressure applied to the hook cylinder 19C can also be kept low. By the way, when the hook 19 grabs the attitude support pin 14 of the container 3 located on the ground, the front arm 10 is rotated rearward. At this time, the recess 20 of the fixing hook 19A opens downward, and the front arm 10 is rotated to such an extent that the hook 19 is positioned slightly above the posture support pin 14. The amount of rotation of the front arm 10 does not increase,
Therefore, although the front arm 10 is present between the rear window of the driver's seat and the container 3, only a portion of the front arm 10 blocks the view. That is, within the field of view, only one front arm 10 remains in a posture as if it were standing up. As a result, the state in which both the base and tip sides of the bent front arm are interposed as described in the prior art is not created, and visibility from the rear window of the driver's seat is improved. As a result, the posture support pin 14 can be
It becomes possible to precisely operate the front arm 10 when grasping the front arm 10. In this state, when the swinging hook 19B is rotated from approximately above to below, the recess 20 of the fixed hook 19A is closed, and the posture support pin 14 is moved by the cooperation of the fixed hook 19A and the swinging front arm 19B. Supported. [Effects of the Invention] In the present invention, a swinging hook that closes a recessed portion of a fixed hook and holds a posture support pin is attached, and the center of rotation of the swinging hook is close to the line of action of the force applied to the swinging hook. Since it is provided on the fixed hook, the moment generated when a load is applied to the swinging hook is reduced, and the pressure of the hook cylinder that rotates the swinging hook can be lowered or the capacity of the cylinder can be reduced. On the other hand, even if the front arm is bent in a dogleg shape, when grasping the posture support pin of a container on the ground, the front arm must be rotated greatly and the tip of the There is no need to lower the posture support pin to the bottom, the visibility of the posture support pin from the rear window of the driver's seat is improved, and smooth engagement operation can be realized. [Examples] The present invention will be described in detail below based on Examples. FIG. 1 shows an example of a cargo handling vehicle 1, in which a container 3, which can be detachably attached to a cargo handling device 2, can be loaded and unloaded onto a vehicle body 7. The car body 7 has a container 3
A pair of left and right lift arms 5 (see FIG. 3, only one is shown) are attached to support and load/unload the vehicle, and are supported so as to be rotatable forward and backward about a support shaft 9 fixed to the vehicle body 7. The distal end side of the main body of the lift arm 5 is bifurcated, and the base of the lift arm 5 forms a support portion 6 that engages with a support shaft 4 extending to the left and right of the container 3 to support the container 3. The support shaft 4 is attached above the center of gravity of the container 3, and is mounted on the support part 6 during cargo handling operations. When such a lift arm 5 rotates back and forth, the support shaft 4 comes into sliding contact with the support part 6, and the container 3 maintains a horizontal posture and the vehicle body 7
Loading and unloading is now possible. Incidentally, above the support shaft 9, a connecting shaft 17 is installed to integrate the left and right lift arms 5, 5 and increase rigidity, at a position that does not impede the movement of the container 3 being loaded and unloaded. The lift arm 5 is configured to be rotated forward and backward by the expansion and contraction movement of a lift cylinder 8 that is swingably mounted on the vehicle body 7. The tip of each piston rod is attached to both the left and right lift arms 5 via a pin shaft 18, and when the piston rods extend, the lift arms 5 rotate backwards, and although not shown, the container 3 is lowered to the ground at a position behind the vehicle body 7. . A front arm 10 is provided at the center front of the vehicle body 7 to maintain the attitude of the container 3 during loading and unloading. This front arm 10 is
In order to avoid interference when the container 3 is placed on the vehicle body 7, it is curved in a dogleg shape. It is attached to the vehicle body 7 via a support shaft 13 that is the center of rotation, and its upper tip portion 10a supports or releases an attitude support pin 14 located at the front upper portion 3a of the container 3. A hook 19 that can be opened and closed is attached to the camera. As shown in FIG. 2, the hook 19 includes a fixed hook 19A, a swinging hook 19B, and a hook cylinder 19C for rotating the swinging hook 19B.
and a support shaft which is the rotation center 19D of the swing hook 19B. The illustrated front arm 10 and hook 19 are in a position where the container 3 is loaded onto the vehicle body 7 and rolled forward. Fixing hook 19A shown in FIGS. 2 and 3
is integrated into the distal end portion 10a of the front arm 10, and is formed in a U-shape having a recess 20 for accommodating the posture support pin 14. The recess 20 is formed by three inner surfaces 21a to 21a of the fixing hook 19A.
21c, and has an opening through which the posture support pin 14 enters and exits in one direction as shown in the figure. Therefore, the posture support pin 1 in the recess 20
4, a swing hook 19B, which will be described later, swings in the direction of arrow 22 to close the opening. That is, when the fixed hook 19A supports the posture support pin 14, the recess 20 becomes a space surrounded by the inner surfaces 21a to 21c and the inner surface 23b of the swinging hook 19B. Note that the recess 20 of the fixing hook 19A is
As shown in FIG. 6, which will be described later, when grasping the attitude support pin 14 of a container located on the ground, it is set to open downward into which the attitude support pin 14 can be inserted from approximately above. On the other hand, the swinging hook 19B, as shown in FIG. It is swingably mounted and connected via a pin shaft 24 to a hook cylinder 19C mounted on the side wall of the front arm 10. When the swinging hook 19B grasps the posture support pin 14 of the container 3 located on the ground, it is fixed by rotating from approximately upward to downward as shown by the arrow 27 in FIG. The recess 20 of the hook 19A is closed, and the posture support pin 14 is supported in cooperation with the fixing hook 19A. That is, as the hook cylinder 19C expands and contracts, the swinging hook 19B rotates around the support shaft 19D, and can open and close the opening of the recess 20. When the recess 20 is closed, the contents of the container are biased, the center of gravity of the container moves forward, and the container is slightly tilted forward about the support shaft 4 and is tilted forward. is the tip 19
The posture support pin 14 is also brought into contact with the inner surface 23b of b. Further, in this example, when the recess 20 is closed, the inner surface 23a of the base is connected to the inner surface 21a of the fixing hook 19A.
Since it is formed to be in a slightly concave state, the posture support pin 14 is not attached to the inner surface 2 in the concave portion 20.
1a, but not the inner surface 23a. This is based on the consideration that as much as possible, upward force and downward force should not be applied to the swinging hook 19B. As mentioned above, the center of gravity of the container 3 moves forward or backward, and the container 3 tilts forward or backward about the support shaft 4. When the center of gravity moves to the front and the container 3 tilts forward, the posture support pin 14 in the recess 20 shown in FIGS. 4 to 6 pushes down the hook 19 and moves to the position shown in solid lines. When the posture support pin 14 is in contact with the hook 19 at the position shown by the two-dot chain line,
Touch as if pushing up. By the way, as shown in FIG. 2, the rotation center 19D of the swinging hook 19B, which rotates due to the expansion and contraction of the hook cylinder 19C attached to the tip end of the front arm 10, is the line of action of the force applied to the swinging hook 19B. 25, is provided on the fixing hook 19A. When the container 3 is on the vehicle body 7 and the front arm 10 is rotated forward, the position shown in FIG. 4 is as shown in FIG.
These are the inner surfaces 21b and 21c of the fixing hook 19A,
The pressing force is received by the fixed hook 19A and does not reach the swinging hook 19B. On the other hand, the contact position of the posture support pin 14 shown by the two-dot chain line is the inner surface 21.
a and the inner surface 23b of the swinging hook 19B, the thrusting force acts on the swinging hook 19B, and the distance between the line of action 25 of the thrusting force W on the posture support pin 14 and the vertical line passing through the support shaft 19D. L1 is shorter than the distance 2 shown in FIG. 8 described above, and the generated moment is smaller. As a result, the force acting on the hook cylinder 19 is also reduced. As the front arm 10 rotates backward, it assumes the attitude shown in FIG. 5, and the final position shown in FIG. During this period, the posture support pin 14 shown by a solid line and a two-dot chain line
The inner surfaces 21a to 21c of the fixed hook 19A forming the recess 20 and the inner surface 23b of the swinging hook 19B
move. At the contact position of the posture support pin 14 shown by the two-dot chain line in FIGS. 5 and 6, the upward force and downward force acting on the hook 19 are received by the fixed hook 19A, which has strength and rigidity. On the other hand, at the solid line position of the posture support pin 14, force is exerted on the swing hook 19B, but
The distance from the vertical line passing through D is relatively short, such as L2 and L3. Therefore, the generated moment can be kept small. This is done so that the force applied to the hook cylinder 19C is reduced.
This is because the position of the support shaft 19D is selected. The cargo handling vehicle 1 configured as described above can load and unload the container 3 while maintaining a desired horizontal posture in the following manner. In the case of the cargo handling vehicle 1 shown in Fig. 1, the container 3
is loaded on the vehicle body 7, and the support shaft 4 of the container 3 is supported by the support part 6 of the lift arm 5. On the other hand, the posture support pin 14 of the front end upper part 3a of the container 3 is connected to the front end portion 10 of the front arm 10.
It is supported by a hook 19 located at a. If the center of gravity of the container 3 is at the front, the posture support pin 14 shown by the solid line in FIG.
A pressing force is applied to the hook 19 by contacting the inner surfaces 21a and 21b forming the recessed portion 20 of the hook 19. but,
The contact position is the inner surface 21a of the fixing hook 19A,
21b, no force is exerted on the hook cylinder 19C. Conversely, if the center of gravity of the container 3 moves backward, the posture support pin 14 shown by the two-dot chain line will move toward the recess 2.
0, the inner surface 23b of the swinging hook 19B and the inner surface 21a of the fixed hook 19A are brought into contact with each other, and an upward force is applied to the hook 19. For this thrust force, the distance between the vertical line passing through the pivot 19D, which is the center of rotation, and the line of action 25 passing through the posture support pin 14 is L1, which is relatively short as described above.
The force obtained by dividing the moment by L1 shown in the figure also does not become very large. The lift cylinder 8 and the auxiliary cylinder 12 are extended to form the lift arm 5 and the front arm 1.
When the 0 is turned backwards, the hook 19 changes to the position shown in FIG. If the center of gravity of container 3 is at the rear,
No force is applied to the hook cylinder 19C by the posture support pin 14 shown by the two-dot chain line. If the center of gravity of the container 3 is at the front, the posture support pin 14 comes into contact with the inner surface 21c of the fixed hook 19A and the inner surface 23b of the swinging hook 19B. Its inner side 2
3b, the vertical line passing through the pivot 19D, which is the center of rotation, and the posture support pin 1
The distance of the line of action 25 passing through 4 is L2,
There is no problem as it is shorter than the above-mentioned L1. The final backward rotation position shown in FIG. 6 is similar to that shown in FIG. 5, and the force that tends to contract the hook cylinder 19C is small. Note that when the hook cylinder 19C is reduced, the swinging hook 19B
is rotated in the direction of the arrow 26 around the support shaft that is the rotation center 19D, releasing the supported posture support pin 14, and also removing the support shaft 4 of the container 3 from the lift arm 5. Container 3 is unloaded onto the ground. In such an operation, the hook cylinder 19C
Since there is no large force acting on it, there is no need to increase the hydraulic pressure. Therefore, it is possible to reduce the pressure, size, or capacity of the hook cylinder 19C, and furthermore, the rigidity of the swinging hook 19B can be set to an appropriate value. By the way, the front arm 10 assumes a "h" shape in a state in which it is rotated as far as possible toward the rear of the vehicle body in order to grab the container C on the ground. However, when grasping the posture support pin 14 of the container 3, the recess 20 formed in the fixing hook 19A
is opened so that the posture support pin 14 can be inserted from substantially above, and the swing hook 19B
However, since the concave portion 20 is closed by rotating from substantially upward to downward,
The posture support pin 14 can be hooked from above. Therefore, the hook 19 is held at a higher position than the posture support pin 14, and after determining the position of the posture support pin 14, the front arm 10 is
The hook 19 can be lowered by rotating it slightly. At that time, only the base side arm or only the tip side arm of the front arm 10 is present between the container 3 and the rear window of the driver's seat. While looking rearward from the driver's seat, when the vehicle is moved backwards to bring the hook 19 closer to the attitude support pin 14 or when the front arm 10 is slightly rotated to attract the attitude support pin 14, detailed movements are performed remotely. However, the front arm 10 can be kept in a posture close to the shape of a "V" shape, and the field of view becomes a "V" shape as described in the section of the prior art, with two frame materials. There will be no more double blocking. Therefore, the workability when engaging by operation from the driver's seat is dramatically improved.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of a cargo handling device in a cargo handling vehicle to which the present invention is applied, FIG. 2 is a front view of a front arm and hook in the cargo handling vehicle, FIG. 3 is a front view of the cargo handling device, and FIGS. Figure 6 is an explanatory diagram of the state in which the hook supports the posture support pin, Figure 7
9 to 9 are explanatory diagrams of a state in which a hook supports a posture support pin in the prior art. 1... Cargo handling vehicle, 3... Container, 3a... Upper front end, 5... Lift arm, 7... Vehicle body, 8...
...Lift cylinder, 10...Front arm, 1
0a... Tip part, 14... Posture support pin, 19
...Hook, 19A...Fixed hook, 19B...
Swinging hook, 19C...Hook cylinder, 19D
...Rotation center (spindle), 20...Recess, 25...
line of action.

Claims (1)

[Claims] 1. Cargo handling in which a removable container is supported by a pair of lift arms provided on the left and right sides of a vehicle body, and the lift arm is tilted so as to be able to rotate forward and backward by the operation of a lift cylinder to load and unload the container. In the vehicle, in order to maintain the attitude of the container during loading and unloading, a front arm that supports an attitude support pin at the upper front end of the container is rotatably attached to the vehicle body, and the tip of the front arm has the above attitude support pin. A hook for grasping the pin is provided, and the hook is formed with a downwardly-opening recess into which the attitude support pin can be inserted from substantially above when the attitude support pin of the container located on the ground is grasped. When grasping the fixing hook and the attitude support pin of the container located on the ground, the recess of the fixation hook is closed by rotating from approximately upward to downward, and the attitude support pin cooperates with the fixation hook. and a swinging hook that moves and supports the front arm, the center of rotation of the swinging hook rotating due to the expansion and contraction of a hook cylinder attached to the tip of the front arm is the line of action of the force applied to the swinging hook. A cargo handling vehicle, characterized in that the fixed hook is provided in close proximity to the fixed hook.