JP4667802B2 - Forklift cargo handling equipment - Google Patents

Description

  The present invention relates to a forklift loading / unloading device including a fork for loading and supporting a load.

  Conventionally, when handling a load such as a pallet in a forklift, the fork has only been inserted into the insertion port formed in the load and lifted, so the load can swing or slide on the fork. There was a risk of it. Therefore, for example, as described in the following patent document, a technique for holding a load on a fork has been proposed. In the technique described in Patent Document 1, the rod of the power cylinder is extended to swing the lock bar downward to lock the pallet. In the technique described in Patent Document 2, the rod of the power cylinder is By extending, the lock bar is lowered to lock the pallet.

JP 2003-252596 A JP 2004-244144 A

  For example, when handling a pallet as a load, there is a possibility that the pallet swings or slides as soon as the pallet is placed on the fork. It is desirable to prevent this. In addition, it is desirable that the pallet is securely held so that swinging and sliding can be prevented even if there is a heavy object on the pallet.

  Accordingly, the present invention has been made in consideration of the above-described circumstances, and aims to ensure the safety of cargo handling work by preventing the load from swinging or sliding on the fork more appropriately according to the situation. To do.

  In order to achieve the above object, the present invention includes a fork that is inserted into an insertion port formed in a load and abuts the upper surface of the insertion port to support the load, and the insertion together with the fork. A forklift loading and unloading device including a lock arm that is inserted into an opening and presses the lower surface of the insertion port downward, and the lock arm has a position where a tip of the lock arm comes into contact with the lower surface of the insertion port; A base end of the base end is pivotally supported so as to move up and down from a position separated from the lower surface, and a lever pivotally supported integrally with the lock arm; And a drive device coupled to the lever via a shaft and swinging the lever so that the tip of the lock arm moves up and down. The lever has a predetermined distance from the pivot support position of the lever. The long hole changed by the range Made is and, the shaft is inserted into the slots, it has a configuration which is characterized in that it is movable along the said long hole.

According to this, when the shaft moves along the long hole and the distance between the shaft and the pivotal support position of the lever changes, the position at which the driving force that swings the lever from the driving device acts on the lever changes. become. In other words, if the distance between the shaft (force point) and the pivot support position (fulcrum) of the lever is shortened due to the lever principle, even if the lever is swung by the same amount by the drive device, the tip of the lock arm (working point) ) Move more greatly, and the tip of the lock arm can be quickly moved up and down without accelerating the operation of the drive device. Conversely, if the distance between the shaft (power point) and the pivot support position (fulcrum) of the lever increases, the tip of the lock arm (action point) moves when the lever is swung by the same amount by the drive unit. Is smaller than when the distance is short, but the pressing force at the tip of the lock arm increases accordingly, and the lower surface of the insertion port can be pressed more strongly without increasing the driving force of the driving device. .
Therefore, immediately after the load is supported by the fork, first the distance between the shaft and the lever support position of the lever is shortened and the lower surface of the insertion port is quickly pressed with the tip of the lock arm, and then the shaft and lever It is possible to increase the distance from the shaft support position and to strongly press the lower surface of the insertion port at the tip of the lock arm.

  In the present invention, there is provided urging means for urging the shaft in a direction approaching the pivotal support position of the lever along the elongated hole, and the drive device inserts the distal end portion of the lock arm into the insertion portion. The shaft is moved in a direction away from the support position of the lever against the urging force by the urging means by operating to move further downward from the position contacting the lower surface of the mouth. It can be set as the structure characterized by these.

  According to this, the distance between the shaft and the lever support position of the lever is kept short by the biasing means until the tip of the lock arm reaches the position where it abuts the lower surface of the insertion slot. The tip of the arm can be in contact with the lower surface of the insertion port. In addition, after the tip of the lock arm comes into contact with the bottom surface of the insertion slot, the drive device is further operated to move the tip of the lock arm to the direction, and the distance between the shaft and the lever support position is increased. Thus, it is possible to strongly press the lower surface of the insertion port with the tip of the lock arm.

  In the present invention, the driving device is a cylinder that can be expanded and contracted, and one end portion in the expansion and contraction direction is connected to the lever, and the distal end portion of the lock arm moves downward by extending. The lever can be swung as described above.

  According to this, when the cylinder is extended, the lower surface of the insertion port can be pressed by the distal end portion of the lock arm, and the distance between the shaft and the pivot support position of the lever can be increased.

  According to the present invention, the distance between the shaft and the pivot support position of the lever can be shortened, and the lower surface of the insertion port can be pressed quickly with the tip of the lock arm without accelerating the operation of the drive device. Even if the distance between the shaft and the shaft support position of the lever is increased and the driving force of the driving device is not increased, the lower surface of the insertion port can be strongly pressed at the tip of the lock arm.

  Hereinafter, an embodiment in which the present invention is applied to a reach-type forklift (hereinafter simply referred to as a forklift) will be described with reference to the drawings.

  As shown in FIG. 1, this forklift has a reach leg 2 projecting forward at the front lower part of a vehicle body 1, and a carriage 3 is provided so as to be movable back and forth along the reach leg 2. A mast device 4 is erected on the carriage 3, and a lift bracket 5 is provided on the mast device 4 so as to be movable up and down. A shaft 6 is provided on the lift bracket 5 in the left-right direction, and a pair of left and right forks 7 are supported on the shaft 6. Further, a tilt bar 8 is supported on the shaft 6 and can be rotated around the shaft 6 together with the fork 7 within a predetermined range. The lift bracket 5 is provided with a backrest 9 for preventing the load on the fork 7 from collapsing. The tilt bar 8 prevents the load from sliding or swinging on the fork 7. A locking device 10 is provided.

  As shown in FIG. 2, the locking device 10 is inserted into an insertion port formed in the load together with the fork 7, and a pair of left and right lock arms 11 that press the lower surface of the insertion port at the tip thereof, and the fork 7. It is disposed behind (on the vehicle body 1 side), and is provided on a shaft 12 that pivotally supports the base end portion of the lock arm 11, a bar 13 that couples the lock arms 11, and the bar 13 and the tilt bar 8. A spring 14, a lever 15 that is pivotally supported by the shaft 12, and a power cylinder 16 as a drive device of the lock device 10 are provided.

  The lock arm 11 is provided so as to be able to swing around the axis of the shaft 12. The lock arm 11 moves up and down between a position where the tip of the lock arm 11 comes into contact with the lower surface of the loading port of the load and a position away from the lower surface. It is made to move. The lever 15 is provided integrally with the lock arm 11 so as to be swingable about the axis of the shaft 12, and the lock arm 11 is swung by swinging the lever 15 by the power cylinder 16. The tip moves up and down. The lever 15 is provided so as to swing behind the shank portion of the fork 7 (without protruding forward from the front surface of the shank portion). The power cylinder 16 is provided with the expansion and contraction direction facing up and down, the rod portion is connected to the lever 15 as will be described later, and the other end opposite to the rod portion is supported by the tilt bar 8. . The power cylinder 16 swings the lever 15 so that the distal end of the lock arm 11 moves downward by extending, and conversely shortens so that the distal end of the lock arm 11 moves upward. The lever 15 is swung.

  As shown in FIG. 2, an extension rod 17 is connected to the rod portion of the power cylinder 16, and a joint 18 connected to the tip of the extension rod 17 is connected to the lever 15 via a shaft 19. Here, the shaft 19 is provided with its axial direction parallel to the axial direction of the shaft 12. The extension rod 17 is provided with a stopper 20, and a spring 21 is provided between the joint 18 and the stopper 20 to urge the joint 18 downward, that is, in the extending direction of the power cylinder 16.

  As shown in FIG. 3, the lever 15 is formed in a substantially L shape in a side view, a hole 15a through which the shaft 12 is inserted at one end, a long hole 15b through which the shaft 19 is inserted at the other end, and a corner portion. Is provided with a pin 15c. Here, the long hole 15b changes the distance to the pivotal support position of the lever 15, that is, the center position of the hole 15a within a predetermined range. The closer to the pin 15c, the shorter the distance to the center position of the hole 15a. The distance from the center position of the hole 15a becomes longer as the distance from 15c increases. The shaft 19 is inserted into the long hole 15b and moves along the long hole 15b. A spring 22 is provided between the pin 15c and the shaft 19 to urge the shaft 19 so as to draw it toward the pin 15c.

As shown in FIG. 1, the vehicle body 1 is provided with a control device 30 that controls the power cylinder 16. The lock device 10 includes a load sensor 31 that detects that the load has been picked up by the fork 7 from the operation of the lock arm 11, and the load is placed on the ground or a shelf from the operation of the lock arm 11. A loading sensor 32 is provided for detecting this. Signals from these sensors are input to the control device 30 as shown in FIG.
When the load is not on the fork 7, the tip of the lock arm 11 is located slightly above the upper surface of the blade portion of the fork 7, and when the load is placed on the fork 7, Pushed down, the tip of the lock arm 11 moves downward. The load pickup sensor 31 detects such movement of the lock arm 11. On the other hand, when the load is placed on the fork 7 while being placed on the fork 7 and the fork 7 is further lowered and the load is placed, the lock arm 11 is pushed up and the tip of the lock arm 11 moves upward. To do. The load sensor 32 detects such movement of the lock arm 11.

  Further, the locking device 10 is provided with an extension sensor 33 that detects that the power cylinder 16 has performed a predetermined extension operation, and a shortening sensor 34 that detects that a predetermined shortening operation has been performed. The extension sensor 33 detects that the rod portion of the power cylinder 16 has extended to a predetermined length corresponding to a state in which the tip of the lock arm 11 presses the lower surface of the insertion port with a predetermined strength. The sensor 34 detects that the rod portion of the power cylinder 16 has been shortened to a predetermined length corresponding to a state in which the distal end portion of the lock arm 11 is separated from the lower surface of the insertion port and is positioned above the upper surface of the fork 7. Is. And the signal from these sensors is also input into the control apparatus 30, and the control apparatus 30 controls the power cylinder 16 based on each signal.

  When the shortening sensor 34 detects that the rod portion of the power cylinder 16 is shortened to a predetermined length, the control device 30 detects that the load is placed on the fork 7 by the load pickup sensor 31. Then, the extension operation of the power cylinder 16 is started, and the power cylinder 16 is extended until the extension sensor 33 detects that the rod portion has been extended to a predetermined length. In addition, when the extension sensor 33 detects that the rod portion of the power cylinder 16 is extended to a predetermined length, the control device 30 indicates that the load is placed on the ground or the like by the load sensor 32. When detected, the shortening operation of the power cylinder 16 is started, and the power cylinder 16 is shortened until the shortening sensor 34 detects that the rod portion has been shortened to a predetermined length.

Now, as shown in FIG. 5A, when the load is loaded from a state where the load is not on the fork 7, the control device 30 causes the power cylinder 16 to extend as described above. At this time, the shaft 19 is pulled toward the pin 15c by the spring 22, and in this state, the distal end portion of the lock arm 11 contacts the lower surface of the insertion port. As shown in FIG. 5B, the rod portion of the power cylinder 16 does not extend to a predetermined length at which the extension operation is stopped when the distal end portion of the lock arm 11 contacts the lower surface of the insertion port. Further, the extension operation is continued. However, since the tip of the lock arm 11 cannot move any further downward, the shaft 19 moves in the direction away from the pin 15c along the long hole 15b against the biasing force of the spring 22 (here, forward). . Then, as shown in FIG. 5C, when the shaft 19 moves, the rod portion of the power cylinder 16 reaches a predetermined length, the extension operation is stopped, and the distal end portion of the lock arm 11 is inserted. The state where the lower surface of the mouth is pressed downward is maintained.
As shown in FIG. 5A, in the state where there is no load on the fork 7 and the rod portion of the power cylinder 16 is shortened, the power cylinder 16 extends and contracts substantially parallel to the shank portion of the fork 7. As shown in FIGS. 5 (b) and 5 (c), as the rod portion expands and contracts, the fork 7 has a shank portion that is more than the front surface of the shank portion. Swing back and forth within a range that does not protrude forward.

  According to such an embodiment, immediately after the load is supported by the fork 7, the distance between the shaft 19 and the pivot support position of the lever 15 is short. By pressing, it is possible to prevent the load on the fork 7 from swinging or sliding. After that, the rod portion of the power cylinder 16 is further extended to increase the distance between the shaft 19 and the pivotal support position of the lever 15, so that the lower surface of the insertion port is stronger at the distal end portion of the lock arm 11 than when the distance is short. Can be pressed downward. Therefore, it is possible to reliably prevent the load on the fork 7 from swinging or sliding.

  In addition, although said embodiment applies this invention to a reach type forklift, this invention is not restricted to this, It can apply also to the forklift of another form.

1 is a perspective view of a forklift according to an embodiment of the present invention. It is a perspective view of the embodiment of the present invention. It is a perspective view of the embodiment of the present invention. It is a block diagram of an embodiment of the present invention. It is a side view of the embodiment of the present invention.

Explanation of symbols

1 Car body 4 Mast device 5 Lift bracket 7 Fork 8 Tilt bar 10 Lock device 11 Lock arm 12 Shaft 15 Lever 15b Long hole 15c Pin 16 Power cylinder 18 Joint 19 Shaft 22 Spring 30 Control device

Claims (2)

A fork that is inserted into an insertion port formed in the load, supports the load by contacting the upper surface of the insertion port, and is inserted into the insertion port together with the fork. A forklift loading / unloading device including a lock arm that presses downward, wherein the lock arm moves up and down between a position where a tip end of the lock arm abuts on a lower surface of the insertion port and a position separated from the lower surface. The base end portion is pivotally supported so as to be swingable, and a lever pivotally supported integrally with the lock arm is coupled to the lever via a shaft. A drive device that swings the lever so that the tip of the lock arm moves up and down, and the lever is formed with a long hole whose distance to the pivot support position of the lever is changed within a predetermined range. The shaft is Is inserted into the hole, is provided movably along said long holes, also the shaft, includes a biasing means for biasing in a direction to approach the pivotally supported position of the lever along the slots, the The drive device operates to move the tip end portion of the lock arm further downward from the position where it abuts the lower surface of the insertion port, so that the shaft is moved against the urging force of the urging means. A forklift loading / unloading device characterized by being moved in a direction away from the shaft support position . The drive device is an extendable cylinder, and one end portion in the extend / contract direction is connected to the lever, and the lever is swung so that the tip end portion of the lock arm moves downward by extending. The forklift loading / unloading device according to claim 1 .

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