JP4737497B2 - Pallet lock device - Google Patents

Description

  The present invention relates to a pallet locking device that locks a pallet inserted into a fork of a forklift so as not to swing.

  The above pallet locking device prevents an accident where the operator who performs the picking work by swinging the pallet in the order picking truck in which the operator can perform the picking work on the pallet inserted in the fork does not cause a fall accident. It was developed. Since the pallet locking device can prevent the load on the pallet from collapsing by preventing the pallet from swinging, the pallet locking device is not limited to the order picking truck but can be used for all forklifts equipped with a fork. it can. As a basic structure of the pallet locking device, there is one that locks a pallet by pressing it up and down by turning a lock bar provided along the inside of the fork of the forklift. For example, it is disclosed in the following Patent Document 1.

  Conventionally, wooden pallets that are pressed by the lock bar have been used in many cases. However, wooden pallets are weak in durability and have a short service life, and recently, resin pallets with excellent durability have been used in many cases. It is coming. The resin pallet generally has a lattice hole formed on the surface of the pallet in order to reduce the weight and material cost. When the lock pallet is pressed by the lock bar and locked, the tip of the lock bar fits into the lattice hole on the surface of the resin pallet, making it difficult to unload, and unloading may not be possible.

Therefore, in order to prevent the tip of the lock bar from fitting into the lattice hole of the resin pallet, the shape of the tip of the lock bar is extended along the fork, and when the resin pallet is pressed, the surface of the resin pallet A pallet locking device that is horizontal is disclosed in Patent Document 2 below.
JP 2003-252596 A JP 2003-267688 A

  However, since the size of the resin pallet varies depending on the load of the pallet, the size of the rack shelf, and the purpose of use, the pallet locking device of the above-mentioned Patent Document 2 has a resin pallet with the tip of the lock bar depending on the resin pallet size. It may not be horizontal with the surface of the resin and may fit into the lattice holes of the resin pallet. That is, the pallet locking device of Patent Document 2 has a problem that it may not be able to handle resin pallets of different sizes.

  In order to solve the above problem, it is possible to make the entire lock bar wide so that the tip of the lock bar does not fit into the lattice hole of the resin pallet. Therefore, there is a problem that the operation is not agile. Further, if the operation of the lock bar is to be accelerated, the force applied to the lock bar must be increased, resulting in an electrical and mechanical burden.

  An object of the present invention is to provide a pallet locking device that can press resin pallets of different sizes without the tip of the lock bar being fitted into the lattice hole of the resin pallet and without making the entire lock bar wide. To do.

The present invention is a pallet locking device for fixing the pallet by pressing a pallet deck board inserted into a fork in a vertical direction with a lock bar provided in parallel with the fork, wherein the lock bar includes the deck It consists of a head part that contacts the board, an arm part that supports the head part, and a widened part provided in the head part, and the widened part is orthogonal to the fork so as to be larger than the width of the lattice hole of the pallet. It is characterized by being formed extending in the direction .

Furthermore, in the pallet locking device according to the present invention, the lock bar is formed in a substantially L shape by extending the widened portion from the tip of the arm portion in one direction perpendicular to the fork. Features. Alternatively, the lock bar is formed in a substantially T shape by extending the widened portion from both ends of the arm portion in a direction orthogonal to the fork.

  In the pallet locking device according to the present invention, the tip of the lock bar does not fit into the lattice hole of the resin pallet, and the resin pallets having different sizes can be pressed. In addition, the operation of the lock bar is not lost.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view in which a pallet locking device 20 is provided on a forklift called a so-called order picking truck on which an operator carries on a cab 3 or a pallet 6 to perform a cargo handling operation at a high place.

  A mast device 10 is provided at the center of the forklift 1, and along this mast device 10, a cab 3 for an operator to board is supported so as to be movable up and down. A pair of forks 2 is fixed to the rear side of the vehicle body of the cab 3 so as to protrude, and on the opposite side of the fork 2, that is, in front of the vehicle body, a motor for driving the vehicle body and a device for cargo handling are provided. A drive unit 11 including a hydraulic motor for driving the vehicle is disposed, and a fence-like head guard 12 is provided above the cab 3 for operator protection. A handle 13 is provided on the front left portion of the cab 3, and an operating device 18 including an accelerator for moving the vehicle body in the front-rear direction and a switch for raising and lowering the cab 3 and the fork 2 is provided on the right front portion. ing. Further, a substantially U-shaped safety bar 14 for protecting the operator is provided above the cab 3, and a brake pedal 16 is provided on the floor surface of the cab 3 (upper surface of the pedestal 4).

  Next, the configuration of the pallet locking device will be described with reference to FIGS. The pallet locking device 20 is housed and disposed in a flat pedestal 4 below the cab 3, and a lock bar 21 for locking the pallet is parallel to the fork 2 from the front plate 17 of the pedestal 4. Protruding. The lock bar 21 is formed in a substantially L shape facing each other in plan view, and a base portion is bolted to a plate-like bracket 23 so that the entire shape is formed in a substantially U shape by the two lock bars 21. It is in the state. In addition, an inclined portion 22 that is inclined downward toward the tip is formed at the top of the tip portion of both lock bars 21. The end of the bracket 23 is supported by a shaft 26 provided horizontally on the pedestal 4 so as to be pivotable up and down, so that the lock bar 21 can swing up and down around the shaft 26.

  In addition, a power cylinder 30 as a driving device for the lock bar is disposed in the pedestal 4 in the longitudinal direction of the vehicle body, and a rod 32 of the power cylinder 30 is attached to an end of the power cylinder 30. The motor 31 can be expanded and contracted via a gear (not shown) by forward rotation and reverse rotation. In addition, on both sides of the power cylinder 30, an input detection sensor 28 that detects a state in which the rod 32 is housed and an output detection sensor 29 that detects a state in which the rod 32 is extended are provided. Note that the input detection sensor 28 and the output detection sensor 29 are constituted by magnetic sensors, for example.

  A link pair 34 is connected to the tip of the rod 32 via a shaft 36, and the lower end of the link pair 34 is rotatably connected to a shaft 35 supported by the pedestal 4. In addition, one end of a damper 40 is rotatably connected to the center of the link body 34 by a shaft 37, and the other end of the damper 40 is provided with a projecting portion 27 projecting from the upper surface of the bracket 23 and a shaft 41. It is connected via a pivot. The damper 40 absorbs a force applied to the lock bar 21 when the pallet 6 is locked as will be described later, and a coil spring is disposed inside.

  As shown in FIG. 3, in the state where the rod 32 of the power cylinder 30 is housed, the link body 34 is located on the left side of the drawing with the shaft 35 as the center, and is further connected to the link body 34. The damper 40 is urged to the left. As a result, the bracket 23 and the lock bar 21 swing counterclockwise about the shaft 26, and the lock bar 21 maintains a horizontal state in which the lock bar 21 is in the same vertical position as the fork 2 in a side view. In this state, when power is applied to the motor 31 and the rod 32 of the power cylinder 30 extends, the link body 34 is urged to the right in the figure about the shaft 35 as shown in FIG. When the damper 40 is urged to the right, the bracket 23 swings clockwise about the shaft 26. That is, as indicated by the solid line, the lock bar 21 swings clockwise around the shaft 26 and presses or presses the upper surface of the lower deck board of the pallet 6 on the lower surface side of the tip of the lock bar 21. The pallet 6 is locked by the lock bar 21.

  Conversely, by reversing the direction of the voltage applied to the motor 31, the rod 32 of the power cylinder 30 is housed, the link body 34 rotates to the left about the shaft 35, and the damper 40 also moves to the left. By interlocking with each other, the bracket 23, that is, the lock bar 21, rotates counterclockwise around the shaft 26 and returns to the horizontal state.

  In addition, as shown in FIGS. 6 and 7, the pallet lock device 20 is provided with sensors for detecting the operation of each part. A magnet (a black member in the figure) 42 is provided on the back of the bracket 23 that fixes the lock bar 21. The magnet 42 is turned on (or turned off) to output a detection signal. A pallet detection sensor 43 including a magnetic sensor and a landing detection sensor 44 are provided. As shown in FIGS. 6A and 6B, a pallet detection sensor 43 that is turned on by the magnet 42 when the lock bar 21 is in a horizontal state is provided, and as shown in FIG. 6C. A landing detection sensor 44 that is turned on by the magnet 42 when the tip of the lock bar 21 turns downward by a predetermined angle is provided.

  FIG. 5 is a block diagram relating to the control of the pallet locking device 20. Signals from the pallet detection sensor 43 and the landing detection sensor 44 are input to the control device 45 composed of the MPU, and the motor 31 is rotated forward and backward by the control device 45. The rod 32 of the power cylinder 30 is expanded and contracted, and the pallet 6 is locked and released by the lock bar 21. Further, signals from detection signals from the input detection sensor 28 and the output detection sensor 29 are input to the control device 45.

  Next, the operation of locking the pallet 6 by the pallet locking device 20 will be described with reference to FIG. 6, and then the unlocking operation will be described. First, as shown in FIG. 6 (a), when the fork 2 is inserted into the pallet 6 while the lock bar 21 remains in a horizontal state, the lock bar 21 is placed next to the fork 2 as shown in FIG. 6 (b). The tip is inserted into the pallet 6. When the fork 2 is further inserted, the upper surface of the inclined portion 22 of the lock bar 21 comes into contact with the end surface of the upper deck board 6a of the pallet 6, so that the lock bar 21 is inclined downward according to the inclination angle of the inclined portion 22. To go. When the entire inclined portion 22 of the lock bar 21 enters the pallet 6 as shown in FIG. 6C, the fork 2 completely enters the pallet 6 as shown in FIG. , The position of the magnet 42 rotates clockwise from the position of the pallet detection sensor 43 and moves from the ON position to the OFF position. Thereby, the pallet detection sensor 43 is turned off, and the lock bar 21 is automatically driven when the pallet 6 is inserted into the fork 2.

  That is, the pallet detection signal from the pallet detection sensor 43 is input to the control device 45, and at the same time, it is determined from the signals from the input detection sensor 28 and the output detection sensor 29 that the rod 32 of the power cylinder 30 has not come out. The control device 45 determines that 32 has not come out (expanded). Upon receiving these signals, the control device 45 causes the motor 31 to rotate forward, for example, to extend the rod 32 of the power cylinder 30 and further rotate the lock bar 21 downward as described above. With the rod 32 of the power cylinder 30 extended, the tip of the lock bar 21 presses or presses the upper surface of the lower deck board 6 b of the pallet 6. As a result, the pallet 6 is locked by the lock bar 21. At the same time, by detecting the signal of the output detection sensor 29 that detects that the rod 32 of the power cylinder 30 has come out, it is determined that the lock bar 21 has locked the pallet 6, and the motor 31 stops.

  FIG. 6D shows a state where the fork 2 is lifted and the pallet 6 is lifted by the fork 2 after the lock bar 21 contacts the lower deck board 6b as described above. . Since the magnet 42 is separated from the pallet detection sensor 43 and the landing detection sensor 44, the pallet detection sensor 43 and the landing detection sensor 44 are turned off. Until then, the power cylinder 30 is controlled so that the lock of the pallet 6 is maintained by the lock bar 21. Further, when the fork 2 is inserted into the pallet 6 and is locked by the lock bar 21 after the pallet 6 is detected, and the pallet 6 is lifted by the fork 2 as the fork 2 is lifted, the damper 40 described above is slightly The lock to the pallet 6 is maintained by the extension and the elasticity.

  Next, the unlocking operation of the pallet locking device 20 will be described. FIG. 7A shows a state in which the pallet 6 is locked by the lock bar 21 and the pallet 6 is lifted by the fork 2 to convey the load. In this state, the lock bar 21 is urged in the direction indicated by the arrow in the figure, and the magnet 42 is disengaged from the landing detection sensor 44. Therefore, both the landing detection sensor 44 and the pallet detection sensor 43 are in the off state. . Next, as shown in FIG. 7B, when the fork 2 is lowered and placed on the pallet 6 on the placing portion 47 such as a shelf or the ground (floor surface), the fork 2 is placed on the upper deck board 6 a of the pallet 6. By descending from the ceiling surface, the position of the shaft 26 of the lock bar 21 also moves together. Therefore, the lock bar 21 rotates counterclockwise by the angle α1 about the shaft 26 as the damper 40 contracts. The rotation of the lock bar 21 rotates the position of the magnet 42 to the position of the landing detection sensor 44, and the landing detection sensor 44 is turned on by the magnet 42.

  The on signal of the landing detection sensor 44 and the on signal of the output detection sensor 29 of the rod 32 are input to the control device 45, and the control device 45 reverses the motor 31, for example, to accommodate the rod 32 of the power cylinder 30. As shown in FIG. 7C, the lock bar 21 is rotated to the horizontal state, so that the pallet 6 is unlocked. Note that the lock bar 21 is naturally in a horizontal state (unlocked state) in a state where the rod 32 of the power cylinder 30 is housed. When the on / off detection sensor 28 that detects that the rod 32 of the power cylinder 30 is inserted is turned on, the controller 45 recognizes that the lock is released.

  Next, the shape of the lock bar 21 of the pallet lock device 20 will be described. As shown in FIG. 1, each head portion 50 of the pair of lock bars 21 is provided with a pair of widened portions 60 extending opposite to each other. FIG. 8 shows one shape of the pair of lock bars 21 in detail. Since the other lock bar 21 has a bilaterally symmetric configuration, the illustration is omitted.

  As shown in FIG. 8, the lock bar 21 may be a substantially L-shaped casting or the like in which the arm portion 70, the head portion 50, and the widened portion 60 are integrated. However, as shown in FIG. The part 60 may be a separate body, and these may be detachably attached via bolts 61. Alternatively, as shown in FIG. 10, it may have a substantially T shape in which two widened portions 60 are formed with the head portion 50 interposed therebetween. Thus, the widened portion 60 may extend in a direction perpendicular to the longitudinal direction and along the lower deck board 6 b, in other words, in a form extending in one side or both sides perpendicular to the fork 2.

  Next, the size of the widened portion 60 of the lock bar 21 will be described. As shown in FIG. 11, the width d1 of the widened portion 60 of the lock bar 21 is formed to be larger (d2 <d1) than the width d2 of the lattice holes of the resin pallet 6p. By doing so, when the lock bar 21 presses the resin pallet 6p, the tip of the lock bar 21 does not fit into the lattice hole.

  As described above, since the lock bar 21 is provided with the widened portion 60 in the head portion 50 that rotates around the horizontal shaft 26 that supports the base end of the arm portion 70, the head portion 50 of the lock bar 21. Is rotated around the shaft 26 and pressed against the upper surface of the pallet 6 or the like, the widened portion 60 is brought into close contact with the upper surface of the pallet 6 together with the head portion 50. Therefore, the lock bar 21 can press the pallet 6 regardless of the size of the pallet 6. Here, the “upper surface etc.” means an upward surface related to the pallet 6, and any surface that can be pressed by the head unit 5 such as the upper deck board 6 a or the frame body in addition to the lower deck board 6 b. Is included.

  In the state where the head portion 50 is pressed against the upper surface of the pallet 6 and the like as described above, the widened portion 60 has a shape extending in the vehicle width direction along the shaft 26, and therefore, in an elongated range extending along the vehicle width direction. The top surface of the pallet 6 can be in close contact. According to the present invention, the tip of the lock bar does not fit into the lattice hole of the resin pallet, and the resin pallet having a different size can be surely pressed. Further, if the entire lock bar is wide, the lock bar becomes heavy and the operation becomes slow. However, in the present invention, only the head part at the tip of the lock bar is wider than the lattice hole of the resin pallet. Only the lock bar is not particularly heavy and the operation is not agile.

  It should be noted that the present invention can be implemented in a mode in which various improvements, modifications, or variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. In the above embodiment, the order picking truck has been described as an example. However, the present invention is not limited to this, and can be applied to various forklifts such as a reach forklift and a counterbalance forklift.

  The present invention is useful for stably supporting a pallet with a fork and preventing inadvertent load collapse and the like.

It is the perspective view seen from the back of the forklift in an embodiment of the invention. It is a top view of the driver's cab which shows the structure of the pallet locking device in embodiment of this invention. It is a side view of the driver's cab which shows the structure of the pallet locking device in embodiment of this invention. It is a principal part block diagram of the pallet lock apparatus in embodiment of this invention. It is a block diagram related to the pallet locking device in the embodiment of the present invention. (A)-(d) is operation | movement explanatory drawing at the time of locking the pallet in embodiment of this invention with a lock bar. (A)-(c) is operation | movement explanatory drawing in the case of unlocking | releasing the pallet in embodiment of this invention. The perspective view which shows the 1st example of the lock bar applied to the pallet locking device which concerns on embodiment of this invention. The perspective view which shows the 2nd example of the lock bar applied to the pallet lock apparatus which concerns on embodiment of this invention. The perspective view which shows the 3rd example of the lock bar applied to the pallet locking device which concerns on embodiment of this invention. It is a top view in which the lock bar applied to the pallet locking device according to the embodiment of the present invention presses the resin pallet.

1: Forklift 2: Fork 3: Driver's cab 6: Pallet 6a: Upper deck board 6b: Lower deck board 20: Pallet lock device 21: Lock bar 26: Shaft 30: Power cylinder 31: Motor 50: Head part 60: Widening Part 70: Arm part

Claims (3)

A pallet locking device for fixing the pallet by pressing the deck board of the pallet inserted into the fork up and down with a lock bar provided in parallel with the fork,
The lock bar includes a head portion in contact with the deck board, an arm portion that supports the head portion, and a widened portion provided in the head portion, and the widened portion is larger than the width of the lattice hole of the pallet. Thus, the pallet locking device is formed to extend in a direction orthogonal to the fork . 2. The pallet lock according to claim 1, wherein the lock bar is formed in a substantially L shape by extending the widened portion from a tip of the arm portion in one side direction orthogonal to the fork. apparatus. 2. The pallet lock according to claim 1, wherein the lock bar is formed in a substantially T shape by extending the widened portion from both ends of the arm portion perpendicular to the fork. apparatus.

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