JP2002338198A - Pallet lock device for forklift truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lock various pallets reliable without damaging them. 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, a lock operating pedal 27 swingably pivoted on a driver's stand 6 via a pivot 25, a connecting link 29 for connecting the pedal 27 to the parallel links 23, and tension springs 32 for tensioning the lock levers 14a in the retracting (b) direction. When the pedal 27 is depressed to advance (a) the lock levers 14a toward a pallet P from inside the driver's stand 6 via the connecting link 29 and the parallel links 23 and against the tension springs 32, an elastic pressing material 14c arranged on tip bottom surfaces of the lock levers 14a presses a top surface of the pallet P.

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, which prevents a pallet from swinging unexpectedly when a load is carried by the fork via the pallet.

[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. 10, 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 outer masts 2 are vertically movable. 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 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. 11 (a), it is possible to sandwich the upper surface plate P1 of the pallet P between the two locking rods 7a and the two forks 5 to reliably prevent the pallet P from swinging unexpectedly. 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.

As another example of the pallet locking device 7, as shown in FIG. 11 (b), the pallet P
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 a 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.

As another example of the pallet lock device 7, as shown in FIG. 11 (c), both lock rods 7a are inserted into the insertion holes Pa of the pallet P in a state where they are at substantially the same horizontal level as the two forks 5. 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 is large, it cannot be applied to the pallet P having a small insertion hole Pa. Further, the types of the pallets are diversified by being molded with a synthetic resin or the like, so that the pallets cannot be applied to, for example, a pallet P having no middle girder P3 at the center.

SUMMARY OF THE INVENTION An object of the present invention is to provide a pallet lock device for a forklift capable of securely locking various pallets without damaging the conventional pallets.

[0009]

In order to achieve the above object, an invention according to claim 1 is provided with a fork extending in a horizontal direction from an elevating body, and an abutting end face of the pallet when the fork is inserted into the pallet. A stopper for defining the insertion depth of the fork with respect to the pallet, and pallet lock means for pressing the pallet on the fork to prevent the pallet from swinging. The pallet is formed so as to be able to protrude and retract on the pallet side with a contact surface between the pallet and the pallet.

According to the above construction, when the fork is inserted into the insertion hole of the pallet, the pallet locking means is sunk into the lifting / lowering 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.

According to a second aspect of the present invention, in the first aspect of the present invention, the pallet locking means has a function of advancing or retracting along a horizontal direction and a function of pressing or releasing a pallet along a vertical direction. It is characterized by having.

According to the above construction, since the pallet locking means is advanced in the raised state, there is no possibility that the pallet locking means will collide with the end surface of the pallet on the fork.
Further, following the advance, the pallet locking means is lowered to press the upper surface of the pallet, so that the pallet locking means and the fork can reliably lock the upper surface of the pallet so as not to be swung unexpectedly.

[0013] The invention according to claim 3 is the invention according to claim 1 or 2.
In the described invention, a driver's cab is provided on the elevating body,
The cab is characterized in that the stopper is formed on a pallet-facing surface of the cab and the pallet locking means is arranged on the cab.

According to the above construction, a picking operation can be easily performed in addition to the operation of locking and unlocking the pallet by an operator riding on the cab.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the pallet locking means and a driving mechanism thereof are provided in the cab, and the pallet locking means is driven by the driving mechanism. When the pallet is advanced to the pallet side through an opening formed on the pallet-facing surface of the driver's cab, the upper surface of the pallet is pressed from above.

According to the above configuration, since the pallet lock means and the drive mechanism thereof are provided in the cab, the worker on the cab smoothly performs various operations without being obstructed by the pallet lock means and the drive mechanism. be able to.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the pallet locking means has a lock rod extending in a horizontal direction, and an elastic member provided on the lower surface of the distal end of the lock rod. A parallel link for supporting the lock rod so as to advance or retract along the horizontal direction, and a lock operating means pivotally supported by the cab via a pivot shaft; A connection link for connecting the lock operation means to the parallel link; and a tension spring for pulling the lock rod in a retracting direction. The connection link and the connection link are operated against the tension spring by operating the lock operation means. The lock rod is advanced to the pallet side via a parallel link, and the upper surface of the pallet is pressed by the elastic material.

According to the above construction, the lock rod is advanced through the connecting link and the parallel link against the tension spring by merely 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.

According to a sixth aspect of the present invention, in the fifth 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 pedal simply by depressing the pedal, so that the advanced state of the lock rod can be reliably locked so as not to be accidentally released. .

According to a seventh aspect of the present invention, in the sixth 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 construction, the lock cam is rotated in the lock release direction only by operating the lock release means, the press-contact state between the lock cam and the interlocking cam is released, and the advanced state of the lock rod is easily released. can do.

[0023]

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. Components other than those described above that are the same as those shown in FIGS. 10 and 11 are given the same reference numerals, and descriptions thereof are omitted.

As shown in FIGS. 2 and 3, the pallet locking means 14 includes a pair of left and right locking rods 14a extending in the horizontal direction, and a cross beam 14b provided between the distal ends of the locking rods 14a. A wide width L elastic member 14c made of rubber or the like fixed to the lower surface of the cross beam 14b, and has a function of advancing or retracting b in the horizontal direction and pallet pressing in the vertical direction (see the solid line in FIG. 2) or It has a function of pressing and releasing, and is capable of appearing and retracting on the pallet P side from the lifting / lowering body 4 side with the contact surface between the stopper 8 and the pallet P (see the phantom line in FIG. 2).

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 6b of the cab 6
27, a connecting link 29 for interlocking and connecting the projection 26a protruding from the hollow shaft 26 to the rear parallel link 23 via a connecting pin 28, and a connecting rod 30 provided between the two lock rods 14a.
, And a tension spring 32 that is stretched to extend to the connecting tool 31 connected to each base material 21 and pulls both lock rods 14a toward the retreat b side.

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 (see FIG. 8). 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 configuration, 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.

Since both lock rods 14a are advanced in the raised state at the time of locking, there is no danger that both lock rods 14a will collide with the end surface of the pallet P, and following the advance a, both lock rods 14a are lowered. Elastic material 1 of wide 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.

As shown in FIGS. 6 and 7, the hollow shaft 2
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.
9, the diameters r1, r2, and r3 of the cam surface 36a are gradually increased in the direction of the arrow d (r1 <r2 <r3), 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 FIG. 7, reference numeral 37 denotes a pressing spring for engaging the lock cam 36 and pressing the cam surface 36a against 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 locking rod 14a in the retreating 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 is turned 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 configuration, 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. 9). ), The advance a state of the lock rod 14a can be easily released.

[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 immersed in the lifting / lowering body side 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.

According to the second aspect of the present invention, since the pallet locking means is advanced in the raised state, there is no danger that the pallet locking means will collide with the end face of the pallet on the fork. Since the pallet locking means is lowered to press the upper surface of the pallet, the pallet locking means and the fork can reliably lock the upper surface plate of the pallet so as not to be swung unexpectedly.

According to the third aspect of the present invention, the picking operation can be easily performed in addition to the operation of locking and unlocking the pallet by the operator riding on the cab.

According to the fourth aspect of the present invention, since the pallet lock means and the drive mechanism thereof are provided in the cab, the worker riding on the cab can perform various tasks without being disturbed by them. Can be performed smoothly.

According to the fifth 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 securely locked so as not to be accidentally swung.

According to the sixth aspect of the present invention, the lock cam is pressed against the outer peripheral surface of the interlocking cam which is interlocked with the depression of the pedal just 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 seventh aspect of the present invention, 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 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 main part 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 a longitudinal sectional view of the essential part in a locked state.

FIG. 9 is an enlarged vertical sectional view in the locked state.

FIG. 10 is a perspective view showing an example of the related art.

FIG. 11 (a) is an enlarged vertical cross-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 Elevator 5 Fork 6 Driver's cab 8 Stopper 11 Opening 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) 29 Connection link 34 interlocking cam 34a outer peripheral surface of interlocking cam 36 lock cam 39 unlocking means P pallet a advance b retreat

Claims (7)

[Claims] A fork extending in a horizontal direction from an elevating body, a stopper for abutting against an end face of the pallet when the fork is inserted into the pallet, and defining a depth of insertion of the fork into the pallet; and a pallet on the fork. And a pallet lock means for preventing the pallet from swinging by pressing the pallet. The pallet lock means is formed so as to be able to protrude and retract from the lifting / lowering body side to the pallet side with a contact surface between the stopper and the pallet. A pallet lock device for a forklift. 2. The forklift according to claim 1, wherein said pallet locking means has a function of advancing or retreating along a horizontal direction and a function of pressing or releasing a pallet along a vertical direction. Pallet lock device. 3. The cab is provided on the elevating body, the stopper is formed on a pallet-facing surface of the cab, and the pallet locking means is disposed on the cab. Item 3. A pallet lock device for a forklift according to item 1 or 2. 4. The pallet lock means and a drive mechanism therefor are provided in the cab, and the pallet lock means is driven by the drive mechanism so that the pallet lock means passes through an opening formed on the pallet facing surface of the cab. The pallet lock device for a forklift according to claim 3, wherein the upper surface of the pallet is pressed from above when the pallet advances to the pallet side. 5. The pallet locking 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 for supporting the vehicle so as to be able to advance or retreat along therewith; a lock operating means pivotally supported by the driver's cab via a pivot shaft; and a connecting link for connecting the lock operating means to the parallel link. A tension spring that pulls the lock rod in the retreating direction, and causes the lock rod to advance toward the pallet via the connection link and the parallel link against the tension spring by operating the lock operation means, The pallet lock device for a forklift according to claim 4, wherein an upper surface of the pallet is pressed by the elastic material. 6. The lock operation 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 pedal is depressed to advance the lock rod toward the pallet. The pallet for a forklift according to claim 5, wherein the interlocking cam is also rotated, and the lock cam, which 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. 7. The pallet lock device for a forklift according to claim 6, further comprising lock release means for rotating said lock cam in a lock release direction.