JP2002338199A - Pallet lock device for forklift truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lock various pallets reliably without damaging them and absorb an excessive load by a collision or the like acting on the pallet. SOLUTION: A pallet lock device for a forklift truck has parallel links 23 for supporting lock levers 14a so that they can advance (a) or retract (b) horizontally, tension springs 32 for tensioning the lock levers 14a in the retracting (b) direction, and a pedal 27 swingably pivoted on a driver's stand 6 via a pivot 25. The parallel links 23 are connected to the pedal 27 by a telescopic connecting link 29 comprising a pair of link members 29A and 29B, and a gap adjusting spring 28 is interposed between the two link members 29a and 29B. While the lock levers 14a press a top surface of a pallet P on forks 5, of a load acts on the pallet P in a pressing canceling direction, the gap adjusting spring 28 absorbs the load.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pallet lock device for a forklift capable of securely locking various pallets without damaging them and absorbing an excessive load caused by a collision or the like applied to the pallets.

[0002]

2. Description of the Related Art Conventionally, as a forklift technology, there is one described in Japanese Patent Application Laid-Open No. Hei 8-165096. As shown in FIG. 12, a pair of left and right outer masts 2 are erected at the front of the vehicle body 1, and a pair of left and right inner masts 3 supported by the two outer masts 2 are movable up and down. A pair of left and right forks 5 are provided so as to be able to ascend and descend and extend horizontally from the lower end of the elevating body 4, and the upper surface of the pallet P on the fork 5 is mounted on a driver's cab 6 fixed to the lower end of the elevating body 4. A pallet lock device 7 is provided to prevent the pallet P from swinging by pressing, and a pallet-facing surface of the driver's cab 6 is a pallet positioning stopper 8. In addition, 9 is a driving operation unit and 10 is a brake pedal.

The pallet lock device 7 is provided in a cab 6 so as to be vertically movable, and has a pair of right and left locks whose front ends extend forward through openings 11 formed in the pallet-facing surface of the cab 6. The rod 7a and the box 12 on the cab 6
And an operation lever 7b which is swingably supported by the lock lever 7a and is linked to the lock rod 7a.

[0004] A description will be given of the baggage transfer procedure.
a, the fork 5 is inserted into the insertion hole Pa of the pallet P, the stopper 8 is brought into contact with the end face of the pallet P, and then the operation lever 7b is operated to lower both lock rods 7a. By moving, the upper end of the pallet P is pressed by the tips of the two lock rods 7a, and subsequently, the lifting body 4 is raised and the vehicle body 1 is moved to convey the load on the pallet P to a predetermined position. I do.

[0005]

In the above-mentioned conventional configuration,
As shown by the solid line in FIG. 13A, it is possible to sandwich the upper surface plate P1 of the pallet P between the two lock rods 7a and the two forks 5 to reliably prevent the pallet P from unexpectedly swinging. However, since the tips of the lock rods 7a always protrude forward from the stopper 8, when the fork 5 is inserted into the insertion hole Pa of the pallet P, the end face of the upper plate P1 is There is a risk of being damaged by hitting the tip.

When an excessive load is applied to the pallet P by pressing the pallet P against an obstacle while the upper surface of the pallet P on the fork 5 is being pressed by both locking rods 7a. In addition, since there is no function of absorbing the excessive load, there is a possibility that the pivots of the lock bars 7a may be damaged.

As another example of the pallet lock device 7, as shown in FIG. 13 (b), the pallet P is held in a state where both lock rods 7a are at substantially the same horizontal level as both forks 5.
It is conceivable to prevent the pallet P from swinging by lowering the distal ends of both the lock rods 7a and pressing the lower surface plate P2 of the pallet P after the insertion into the insertion hole Pa.
In this case, an excessive load is applied in the direction in which the upper surface plate P1 and the lower surface plate P2 are separated from each other, so that the life of the pallet P is shortened and the pallet P cannot be applied to the pallet P without the lower surface plate P2. Furthermore, there is no function of absorbing an excessive load due to a collision or the like on the pallet P.

As a further example of the pallet lock device 7, as shown in FIG. 13 (c), both lock rods 7a are inserted into the insertion holes Pa of the pallet P with the both forks 5 at substantially the same horizontal level. After that, it is conceivable to prevent the swing of the pallet P by bringing the tip ends of the two lock rods 7a closer to each other and sandwiching the middle spar P3 of the pallet P. Since the exclusive width D of the fork 5 and 7a is large, it cannot be applied to a pallet having a small insertion hole Pa. It cannot be applied to the pallet P of the type without the middle girder P3. Furthermore, there is no function of absorbing an excessive load due to a collision or the like on the pallet P.

In view of the conventional problems, the present invention provides a pallet lock device for a forklift capable of securely locking various pallets without damaging them and absorbing an excessive load caused by a collision or the like applied to the pallets. It is intended to provide.

[0010]

In order to achieve the above object, according to the present invention, a fork extending in a horizontal direction from an elevating body, and a pallet is pressed from above after inserting the fork into the pallet. A pallet lock means for preventing the pallet from swinging, a drive mechanism for moving the pallet lock means toward or away from the pallet, and an elastic member for applying an elastic force to the pallet lock means when the pallet is pressed Is provided in the drive mechanism, and when the pallet is displaced upward, the elastic member contracts so that the pallet lock means can be retracted upward.

According to the above construction, when the fork is inserted into the insertion hole of the pallet, the pallet locking means is retracted toward the elevating body so that the end face of the pallet is not damaged by hitting the pallet locking means as in the prior art. it can. In addition, by pressing the upper surface of the pallet on the fork by the pallet locking means that is driven and advanced by driving the drive mechanism, it is possible to reliably prevent the pallet from swinging unexpectedly, and in the pressed state. Even if an excessive load is applied to the pallet by, for example, colliding the pallet with an obstacle, the excessive load is absorbed by an elastic member to prevent the pallet locking means and the drive mechanism from being damaged. Can be.

According to a second aspect of the present invention, in the first aspect of the present invention, a driving cab is provided on the elevating body, and the pallet locking means and a driving mechanism are provided in the driving cab. When the mechanism is driven, the pallet lock means is pushed upward from the upper side when the pallet lock means is advanced toward the pallet through an opening formed in the pallet-facing surface of the driver's cab.

According to the above construction, since the pallet locking means and the drive mechanism thereof are provided in the cab, the worker on the cab can perform the work of locking and unlocking without any obstacles. Picking work and the like can be performed smoothly.

According to a third aspect of the present invention, there is provided the first or second aspect.
In the invention described in the above, the pallet lock means has a lock rod extending in the horizontal direction, and an elastic material provided on the lower surface of the distal end portion of the lock rod, and the driving mechanism moves the lock rod in the horizontal direction. A parallel link that supports the lock rod in the retracting direction, and a lock operating means pivotally supported by the cab via a pivot shaft. The parallel link is connected to lock operation means by a telescopic connection link comprising a pair of link members movably engaged with each other within a predetermined range, and the elastic member is interposed between the two link members. It is characterized by comprising an interval adjusting spring for urging the connecting link in the extension direction.

According to the above construction, the lock rod is advanced through the connecting link and the parallel link against the tension spring only by operating the lock operating means, and the elastic member provided on the lower surface of the distal end portion of the lock rod. By pressing the upper surface of the pallet, the pallet can be securely locked so as not to be swung unexpectedly. Also, in the locked state, even if an excessive load is applied to the pallet by, for example, colliding the pallet with an obstacle, the interval adjusting spring interposed between both link members of the connecting link is compressed by this. Since the excessive load is absorbed, it is possible to prevent the pallet locking means and the drive mechanism from being damaged by the excessive load.

According to a fourth aspect of the present invention, in the third aspect of the invention, the lock operating means comprises a pedal, and an interlocking cam is provided which rotates in conjunction with depression of the pedal, and an outer peripheral surface of the interlocking cam. A rotatable lock cam is provided for contacting the lock cam. When the pedal is depressed to advance the lock rod toward the pallet, the interlocking cam is also rotated. Thus, the advancing state of the lock rod is locked.

According to the above configuration, the lock cam is pressed against the outer peripheral surface of the interlocking cam that is interlocked with the depression of the pedal, so that the lock rod can be reliably locked so that the advanced state is not accidentally released. .

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, a lock release means for rotating the lock cam in a lock release direction is provided.

According to the above configuration, the lock cam is rotated in the unlocking direction only by operating the unlocking means, so that the press-contact state between the lock cam and the interlocking cam is eliminated, and the advanced state of the lock rod is easily released. can do.

[0020]

FIG. 1 shows a forklift provided with a pallet lock device 13 according to an embodiment of the present invention. The pallet lock device 13 is provided with a pallet lock provided in a driver's cab 6. It has means 14 and its driving mechanism 15. Reference numeral 18 denotes a guard lever rotatably provided on the elevating body 4, and reference numeral 19 denotes wheels of the vehicle body 1. 12 and 13 that are the same as those shown in FIGS. 12 and 13 are given the same reference numerals and description thereof is omitted.

As shown in FIGS. 2 and 3, the pallet lock means 14 includes a pair of left and right lock rods 14a extending in the horizontal direction, and a cross beam 14b provided between the distal ends of the lock rods 14a. A wide width L elastic material 14c made of rubber or the like is fixed to the lower surface of the cross beam 14b, and is formed so as to be able to advance a or retract b from the inside of the cab 6 toward the pallet P.

As shown in FIGS. 2 to 7, the drive mechanism 15 swings via a connecting shaft 22 between a pair of right and left base materials 21 fixed on the bottom plate 6a of the cab 6 and each lock rod 14a. A pair of front and rear parallel links 23 which are connected to each other so as to be able to advance or retract the lock rods 14a, and rotatably fit on pivot shafts 25 projecting from a substrate 24 on the bottom plate 6a. A lock operation pedal (lock operation means) extending upward from the hollow shaft 26 through the top plate portion 6b of the cab 6
27, a connecting link 29 for interlockingly connecting the projection 26a protruding from the hollow shaft 26 to the rear side parallel link 23, and a connecting tool 31 connected to each base member 21 from an erecting rod 30 erecting between both locking rods 14a. The locking rods 14a
And a tension spring 32 for pulling the spring toward the retreat b side.

As shown in FIGS. 8 and 9, the connecting link 29 is composed of a pair of link members 29A and 29B whose one ends are engaged with each other, and the other end of one link member 29A is connected. The protrusion 2 is provided via the pin 33a
6a and the other link member 29B
Of the rear parallel link 23 via the connecting pin 33b.
And the other link member 29B is inserted into a through hole of a bracket 29a projecting from one end of one link member 29A.
The screw shaft portion 29b is movably inserted, and a stopper 29d with a lock nut 29c is screwed into the distal end of the screw shaft portion 29b. The other end of the stopper 29d and one link member 29A A spacing adjusting spring (elastic member) 28 is interposed between the receiving seat 29e and the receiving seat 29e, which urges the connecting link 29 in the extending direction.

A description will now be given of the luggage transfer procedure.
With the 4a stored in the cab 6, the fork 5 is inserted into the insertion hole Pa of the pallet P, and the stopper 8 is brought into contact with the end face of the pallet P (see the solid line in FIG. 2). Next, the pedal 27
2 (see the phantom line in FIG. 2), the lock rods 14a advance toward the pallet P via the connecting link 29 and the parallel link 23 against the tension spring 32, and the upper surface of the pallet P is Is pressed (Fig. 10
reference). Subsequently, the lifting body 4 is raised and the vehicle body 1 is caused to travel, so that the load W on the pallet P is transported to a predetermined position.

According to the above structure, as shown by the solid line in FIG. 2, since the lock rod 14a is immersed in the cab 6 in the unlocked state, the fork 5 is inserted into the insertion hole P of the pallet P.
When the pallet P is inserted into the pallet P, there is no possibility that the end face of the pallet P hits the tip of the lock rod 14a and is damaged as in the related art.

At the time of locking, the lock rods 14a are advanced in the raised state so that the lock rods 14a do not collide with the end surface of the pallet P, and the lock rods 14a are lowered following the advance a. Elastic material 1 of wide width L
4c, the upper surface of the pallet P is pressed by the elastic member 14c and the fork 5.
Can be securely locked by being pinched over a wide range.

In the locked state, even if an excessive load is applied to the pallet P by, for example, colliding the pallet P with an obstacle, the distance is adjusted via the lock rod 14a and the connecting link 29 due to the excessive load. Since the spring 28 is compressed and an excessive load is absorbed by the spring 28, it is possible to prevent the pallet locking means 14 and the drive mechanism 15 from being damaged by an excessive load due to a collision with the pallet P or the like. (See the phantom line in FIG. 9).

As shown in FIG. 6 and FIG.
6, a substantially circular interlocking cam 34 is formed integrally concentrically, and an arcuate cam surface 36a of a substantially fan-shaped lock cam 36 rotatably supported by a support shaft 35 protruding from the substrate 24 is interlocked with the interlocking cam 34.
As shown in FIG. 11, the diameters r1, r2, and r3 of the cam surface 36a are gradually increased in the direction of the arrow d (r1 <r2 <r3), and as shown in FIG. A concave portion 34A is formed in the circular outer peripheral surface 34a of the interlocking cam 34 so as to face the large-diameter portion 36A of 36a. In addition,
In FIG. 7, reference numeral 37 denotes a cam surface 36a which engages with the lock cam 36.
Is a pressing spring for pressing the outer peripheral surface 34a of the interlocking cam 34.

In the above configuration, in the unlocked state,
As shown in FIG. 7, the concave portion 34A of the interlocking cam 34 is opposed to the large diameter portion 36A of the cam surface 36a. From this state, the pedal 27 is depressed to advance the lock rod 14a to the pallet P side. The interlocking cam 34 is rotated in the direction of arrow c, and the cam surface 36a of the lock cam 36 that rotates in the direction of arrow d with the rotation is the circular outer peripheral surface 3 of the interlocking cam 34.
The lock rod 14a is pressed into contact with the lock rod 4a and locks the forward a state of the lock rod 14a.

In this locked state, even if an excessive load is applied to the lock rod 14a in the retreat b direction by colliding the pallet P with an obstacle or the like, the interlocking cam 34 is rotated in the direction opposite to the arrow c. As a result, the lock cam 36 turns to the arrow d.
By rotating in the opposite direction, the pressure contact force between the cam surface 36a and the circular outer peripheral surface 34a of the interlocking cam 34 increases, so that there is no possibility that the locked state is accidentally released.

As shown in FIGS. 1 and 7, an unlocking means 39 for rotating the lock cam 36 in the unlocking direction d is provided. It comprises a lever 39a pivotally attached to the elevating body 4 so as to be vertically movable, and a wire rope 39b connecting the lever 39a to the lock cam 36.

According to the above structure, the lock cam 36 is rotated in the direction of the arrow d only by pulling up the lever 39a, and the pressure contact state between the cam surface 36a and the outer peripheral surface 34a of the interlocking cam 34 is eliminated (see the phantom line in FIG. 11). ), Lock rod 14a
Can be easily released.

In the above embodiment, the interval adjusting spring 28
Although the excessive load applied to the pallet P is absorbed by the above, various elastic members such as an air damper and an oil damper may be used instead of the interval adjusting spring 28.

[0034]

According to the first aspect of the present invention, when the fork is inserted into the insertion hole of the pallet, the pallet locking means is retracted toward the elevating body so that the end face of the pallet can be locked in the pallet lock as in the prior art. It can be prevented from being damaged by the means. In addition, by pressing the upper surface of the pallet on the fork by the pallet locking means that is driven and advanced by driving the drive mechanism, it is possible to reliably prevent the pallet from swinging unexpectedly, and in the pressed state. Even if an excessive load is applied to the pallet by, for example, colliding the pallet with an obstacle, the excessive load is absorbed by an elastic member to prevent the pallet locking means and the drive mechanism from being damaged. Can be.

According to the second aspect of the present invention, since the pallet locking means and its driving mechanism are provided in the cab, the worker riding on the cab can be locked and locked without being obstructed by them. Release work and picking work can be performed smoothly.

According to the third aspect of the present invention, the lock rod is advanced via the connecting link and the parallel link against the tension spring only by operating the lock operating means, and the lower end of the lock rod is provided on the lower surface. The upper surface of the pallet is pressed by the provided elastic material, and the pallet can be reliably locked so as not to be swung unexpectedly. In the locked state,
Even if an excessive load is applied to the pallet by, for example, colliding the pallet with an obstacle, the interval adjusting spring interposed between both link members of the connecting link is compressed to absorb the excessive load. The pallet locking means and the driving mechanism can be prevented from being damaged by the excessive load.

According to the fourth aspect of the invention, the lock cam is pressed against the outer peripheral surface of the interlocking cam which is interlocked only by depressing the pedal, so that the locking rod is securely locked so that the advanced state is not accidentally released. can do.

According to the fifth aspect of the present invention, the lock cam is rotated in the unlocking direction only by operating the unlocking means, so that the pressure contact state between the lock cam and the interlocking cam is eliminated, and the lock rod is advanced. Can be easily released.

[Brief description of the drawings]

FIG. 1 is a side view of a forklift provided with a pallet lock device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the pallet lock device in an unlocked state.

FIG. 3 is a horizontal sectional view in the same state.

FIG. 4 is a view as viewed in the direction of arrows AA in FIG. 3;

FIG. 5 is a view taken in the direction of arrows BB in FIG. 3;

6 is a view as viewed in the direction of arrows CC in FIG. 3;

FIG. 7 is a view as viewed in the direction of the arrow DD in FIG. 6;

FIG. 8 is an exploded perspective view of the main part.

FIG. 9 is a side view of the main part.

FIG. 10 is a longitudinal sectional view of the pallet lock device in a locked state.

FIG. 11 is an enlarged vertical sectional view in the locked state.

FIG. 12 is a perspective view showing a conventional example.

FIG. 13 (a) is an enlarged longitudinal sectional view of a main part of the conventional example,
(B) an enlarged vertical section of a main part showing another example of the conventional art, (c)
It is an expanded cross-sectional view of a main part showing still another example of the conventional art.

[Explanation of symbols]

 Reference Signs List 4 Lifting body 5 Fork 6 Cab 13 Pallet lock device 14 Pallet lock means 14a Lock rod 14c Elastic material 15 Drive mechanism 23 Parallel link 25 Pivot shaft 27 Lock operation pedal (Lock operation means) 28 Interval adjustment spring (Elastic member) 29 connecting link 29A one link member 29B the other link member 34 interlocking cam 34a outer peripheral surface of interlocking cam 36 lock cam 39 unlocking means P pallet a advance b retreat

Claims (5)

[Claims] 1. A pallet lock, comprising: a fork extending horizontally from a lifting / lowering body; and pallet locking means for pressing the pallet from above after inserting the fork into the pallet to prevent the pallet from swinging. A drive mechanism is provided for advancing or retracting means to the pallet side, and an elastic member for applying an elastic force to the pallet locking means when the pallet is pressed is provided on the drive mechanism, and the elastic member is displaced upward when the pallet is displaced. A pallet lock device for a forklift, wherein the pallet lock device is retracted so as to be retractable upward. 2. A driver's cab is provided on the elevating body, and the pallet locking means and a driving mechanism are provided in the driver's cab. 2. The pallet lock device for a forklift according to claim 1, wherein the upper surface of the pallet is pressed from above when the pallet advances toward the pallet through an opening formed in the surface. 3. The pallet lock means has a lock rod extending in a horizontal direction, and an elastic member provided on a lower surface of a distal end portion of the lock rod, and the driving mechanism moves the lock rod in a horizontal direction. A parallel link that supports the lock rod in the retracting direction, and a lock operating means pivotally supported by the cab via a pivot shaft. The parallel link is connected to lock operating means by a telescopic connection link comprising a pair of link members movably engaged with each other within a predetermined range, and the elastic member is interposed between the two link members. 3. The pallet lock device for a forklift according to claim 1, further comprising an interval adjusting spring for urging the connecting link in the extension direction. 4. The lock operating means comprises a pedal,
An interlocking cam that rotates in conjunction with the depression of the pedal is provided, and a rotatable lock cam that is in contact with the outer peripheral surface of the interlocking cam is provided, and the lock rod is advanced to the pallet side by depressing the pedal. 4. The pallet for a forklift according to claim 3, wherein the interlocking cam is also rotated, and the lock cam that rotates with the interlocking cam is pressed against the outer peripheral surface of the interlocking cam to lock the advanced state of the lock rod. Locking device. 5. The pallet lock device for a forklift according to claim 4, further comprising lock release means for rotating said lock cam in a lock release direction.