JP2005289630A - Structure of dump cylinder for hinged fork - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a dump cylinder for a hinged fork realizing simplification of the structure and shortening of a vehicle body by non-pivoting the dump cylinder and enhancing driving property by improving front visibility of a finger bar. <P>SOLUTION: The dump cylinder is turnably supported on a liftable hinge frame mounted to a mast device of the hinged fork by a support pin arranged at a position left with a predetermined space in a left/right direction of the vehicle body and the finger bar connected to the dumping cylinder connected at an approximately central position of the vehicle body is made turnable relative to the hinge frame by expansion/contraction. The dump cylinder fixes a rail perpendicular to an axis center of the cylinder and engaged with a roller turnably auxiliarily provided on the finger bar to a distal end of a piston rod. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a structure of a hinged fork dump cylinder having a simplified structure and good operability.

Conventionally, attachments such as forks or buckets attached to a four lift have been known to increase work efficiency by tilting forward and backward greatly by turning the hinged fork device without tilting the mast device. It has been.
As this hinged fork device, one shown in FIGS. 7 to 9 is generally known. 7 to 9, a hinged fork device 61 has a hinge frame 63 mounted on a mast device 65 so as to be movable up and down, and a finger bar 67 is rotatably attached to the hinge frame 63.

The finger bar 67 is rotatably supported by a support pin 69 attached to a frame plate 63a of a hinge frame 63 that is disposed at a predetermined interval in the left-right direction of the vehicle body. The support pins 69 connect the finger plate 67 a of the finger bar 67 and the frame plate 63 a of the hinge frame 63.
The finger bar 67 is disposed at the center position CL of the vehicle body, and is connected to a dump cylinder 71 attached to the hinge frame 63 via a rod pin 73 and a cylinder plate 75. The finger bar 67 is rotatable about a support pin 69 with respect to the hinge frame 63 by expansion and contraction of the dump cylinder 71. The hinged fork device 61 has a backrest 77 attached above the finger bar 67.

The dump cylinder 71 has a rod head 71 a sandwiched between a pair of cylinder plates 75 of the finger bar 67 and is connected by a rod pin 73 through which the rod head 71 a and the cylinder plate 75 are inserted. . The dump cylinder 71 is attached to the hinge frame 63 by a trunnion 81 so as to be swingable in the longitudinal direction of the vehicle body.
The trunnion 81 is disposed between the backrest 77 and the mast device 65 and above the finger bar 67, and is attached to the hinge frame 63.

For example, when the piston rod 71b is extended so that the rod pin 73 moves from the position P0 to the position P1, the dump cylinder 71 rotates the finger bar 67 with the support pin 69 of the hinge frame 63 as a fulcrum. While rotating 35 degrees in the upward direction indicated by the alternate long and short dash line, it also swings rearward of the vehicle body, and its upper part is close to the mast device 65.
Further, when the piston rod 71b is contracted so that the rod pin 73 moves from the position P0 to the position P2, the dump cylinder 71 rotates the finger bar 67 with the support pin 69 of the hinge frame 63 as a fulcrum, thereby While rotating 50 degrees in the downward direction indicated by the two-dot chain line, it also swings rearward of the vehicle body, and its upper part is closer to the mast device 65 than when it is extended.

The dump cylinder 71 is connected to the steel pipe 87 attached to the hinge frame 63 by an extension rubber hose 85 attached to the bottom side thereof, and to the steel pipe 91 by a reduction rubber hose 89 attached to the rod side. Further, the dump cylinder 71 is allowed to swing when the rubber hoses 85 and 89 are bent.
Since the forklift is arranged in a left-right direction from the center position CL of the vehicle body, for example, on the left side in the country and on the right side in the foreign country, the eye point is similarly positioned from the center position CL. The position is spaced apart in the left-right direction. In the present specification, in the left-right direction of the vehicle body, the left side refers to the left direction when viewed from the front of the driver's seat.

However, the conventional dump cylinder is connected to the finger bar by a pin for the rod, and swings greatly in the front-rear direction of the vehicle body around the trunnion attached to the hinge frame as the finger bar rotates. Yes. For this reason, in the conventional hinged fork, it is necessary to arrange the trunnion attachment position in front of the vehicle body so as not to interfere with the hinge frame or the mast device when the dump cylinder swings. As a result, the distance between the hinge frame and the backrest and the distance between the hinge bar and the finger bar that supports the fork are increased, and the position of the attachment such as the fork relative to the vehicle body (mast device) is increased. It is arranged far away in the front.
This hinged fork has a problem that the load position is greatly increased forward from the vehicle body, so that the allowable load weight is reduced, the longitudinal direction of the vehicle body is lengthened, turning performance and stability are lowered, and driving performance is poor.

  Further, since the dump cylinder swings, it is necessary to use a rubber hose for supplying and discharging the pressure oil to and from the dump cylinder. For this reason, the hinged fork requires a large space for allowing the rubber hose to bend and the piping becomes complicated, and, similarly to the above, the distance between the hinge frame and the backrest is increased and the structure is complicated. It has become. Moreover, since a rubber hose is used, there exists a problem that cost becomes high.

  In the hinged fork equipped with the hinged fork device, the operator views the fork of the front attachment, for example, from the gaps S3 and S4 between the support pin and the rod pin, that is, between the finger plate and the cylinder plate. . At this time, since the cylinder plate is disposed at the center position of the vehicle body, as shown in FIG. 10, the viewing angle Θ3 seen from the right gap S3 between the finger plate and the cylinder plate and the left gap S4 are shown. The angle of view Θ4 visible from the camera is in a narrow range.

  In particular, when the eye point is at a position shifted to the left side from the center position CL of the vehicle body, for example, the viewing angle Θ3 seen from the right side gap S3 required by a wide range where the tip of the fork is desired is seen from the left side gap S4. The angle of view is smaller than Θ4. For this reason, the operator has a problem that the drivability is not good because the tip of the fork cannot be seen unless the eye point E is moved.

  The present invention was made paying attention to the above problems, and relates to the structure of a hinged fork dump cylinder, and in particular, the dump cylinder is made non-oscillating to simplify the structure, shorten the vehicle body, An object of the present invention is to provide a hinged fork dump cylinder structure in which the forward visibility of the finger bar is improved and the operability is improved.

  In order to achieve the above object, according to the first aspect of the present invention, a liftable hinge frame attached to a mast device of a hinged fork is rotated by a support pin disposed at a predetermined distance in the left-right direction of the vehicle body. Hinged fork dump cylinder structure that allows the finger bar connected to the dump cylinder, which is supported at the center position of the vehicle body, to move freely with respect to the hinge frame by expansion and contraction of the dump cylinder. The dump cylinder has a fixed rail at the tip of the piston rod that is substantially perpendicular to the axis of the cylinder and engages with a roller attached to the finger bar so as to be rotatable. It is said.

  The second invention, which is mainly composed of the first invention, is characterized in that the dump cylinder is attached to the hinge frame in a non-oscillating manner.

  According to a third aspect of the invention, the first aspect of the invention is characterized in that the rail has at least a U-shape facing the cylinder plate of the finger bar and opening.

  According to a fourth aspect of the invention based on the first aspect, the dump cylinder is connected to a steel pipe fixed to the hinge frame.

  In the first invention or the fifth invention based on the third invention, the rail is arranged on the opposite side of the eye point which is disposed in the left-right direction from the center position of the vehicle body with respect to the cylinder plate of the finger bar. It is characterized by being installed.

  According to the first invention, in the dump cylinder, the rail at the tip of the piston rod is engaged with a roller rotatably attached to the finger bar, and the roller rotates in the rail as the dump cylinder expands and contracts. The finger bar is rotated with respect to the hinge frame. Thereby, the dump cylinder can be made non-oscillating with respect to the hinge frame, and the structure of the hinged fork device can be simplified.

According to the second invention, since the dump cylinder is attached to the hinge frame in a non-oscillating manner, the hinged fork has a distance between the hinge frame and the backrest and a distance between the hinge frame and the finger bar that supports the fork. The distance to the position of the attachment such as a fork relative to the vehicle body can be reduced.
This hinged fork can increase the allowable load weight because the load position can be close to the vehicle body, and can shorten the longitudinal direction of the vehicle body, thereby improving the turning performance and stability.

  According to the third aspect of the invention, at least the U-shaped rail fixed to the piston rod faces the cylinder plate of the finger bar, and the U-shaped opening opens toward the side of the play to the roller. Since it is engaged, the piston rod does not rotate. As a result, the rail and the roller do not come off, the roller rolls inside the rail, and the rail can reliably guide the roller. Alternatively, the rail is formed in a U-shape (lip groove shape) having a lip on at least one side, and the piston rod reliably guides the roller along the rail without rotating.

  According to the fourth invention, since the dump cylinder is connected by the steel pipe, the structure can be simplified and the cost and the number of assembly steps can be reduced. Moreover, since it connects with the steel pipe, a field area becomes small and the effect similar to 2nd invention is acquired.

  According to the fifth invention, the cylinder plate provided with the roller engaging with the rail is disposed, for example, on the eye point side from the center position of the vehicle body. The angle Θ1 that can be seen from the right-side gap S1 that needs to be increased is widened, and the operator can move the eye point E without moving it or slightly to improve drivability.

Hereinafter, the best mode of the structure of a dump cylinder of a hinged fork according to the present invention will be described with reference to the drawings.
FIG. 1 is a front view of a hinged fork device of a hinged fork according to the present invention.
FIG. 2 is a side view of FIG. 1 according to the present invention.
3 is a plan view of FIG. 1 according to the present invention.
FIG. 4 is a side view of the dump cylinder of the hinged fork device according to the present invention.
FIG. 5 is an enlarged view of a rail and a roller portion according to the present invention.
FIG. 6 is a view for explaining a front view of the hinged fork device according to the present invention.
The same parts as those in the conventional example are denoted by the same reference numerals, and description thereof is omitted.

1, 2, and 3, a mast device 65 is attached to the front of the forklift so as to be tiltable in the front-rear direction. The hinged fork device 1 is attached to the mast device 65 by a roller 3 so as to be movable up and down. ing.
In this forklift, for example, a driver's seat (not shown) is disposed on the left side of the center position CL (shown in FIGS. 1 and 3) of the vehicle body, and the eye point E is similarly positioned at the center position as shown in FIG. It is at a position spaced leftward from CL.

In the hinged fork device 1, a hinge frame 4 provided with a roller 3 is mounted on a mast device 65 so as to be movable up and down, and a finger bar 5 is rotatably attached to the hinge frame 4.
The hinge frame 4 is provided with a pair of frame plates 4a, 4a spaced apart from each other by a predetermined distance in the left-right direction of the vehicle body, and support pins 69 are inserted into the holes 4b of the frame plates 4a. . The support pins 69 connect the finger bar 5 and the hinge frame 4 and support the finger bar 5 so as to be rotatable with respect to the hinge frame 4.

  The finger bar 5 is provided with a pair of grooved bars 7 and 7 spaced apart from each other by a predetermined distance in the vertical direction. An attachment such as a fork 83 is attached to the grooved bars 7 and 7. The pair of grooved bars 7 and 7 are connected by a pair of finger plates 5a sandwiching a frame plate 4a arranged in the left and right direction, and the upper and lower grooved bars 7 and 7 are for left and right fingers. The plate 5a and a cylinder plate 11 described later form the finger bar 5 in a sheet metal frame.

The pair of finger plates 5a have holes 5b, and the finger bars 5 and the hinge frame 4 are rotatably connected by support pins 69 that pass through the holes 5b.
Further, the pair of grooved bars 7 and 7 are connected by a single cylinder plate 11 at a substantially center position CL of the vehicle body and at a position shifted to the eye point E side. One cylinder plate 11 is formed in a substantially triangular shape toward the rear of the vehicle body from the pair of grooved bars 7, 7, and is located near the apex and at a position on the mast device 65 side. 11 is provided with a rotatable roller 13 on the side surface.

As shown in FIG. 1, one end surface of the roller 13 is attached to the side surface of the cylinder plate 11 and is disposed on the side of the center position CL of the vehicle body. Engage and roll in the rail 15.
As shown in FIG. 4, the rail 15 is fixed to the piston rod 17 a of the dump cylinder 17. Specifically, the rail 15 is formed in a U shape as shown in FIG. 5A, the opening 15a faces the cylinder plate 11, and the groove 15b is dumped as shown in FIG. The piston 17 is fixed to the tip of the piston rod 17a so as to be orthogonal to the axis Sc of the cylinder 17.

The rail 15 has a small clearance Ca between the cylinder plate 11 and abuts when the piston rod 17a rotates in the axial direction (arrow Wa) to prevent further rotation. ing.
Alternatively, as shown in FIG. 5 (b), the first rail 15A is formed in a U-shape (lip groove shape) having at least one lip 15c, and the piston rod 17a does not rotate and has a shaft core. The roller 13 is reliably guided along the direction groove 15b.

As shown in FIGS. 1 to 3, the dump cylinder 17 has a trunnion 19 attached to the hinge frame 4 with a rectangular shape or the like so as not to swing. Alternatively, as shown in FIG. 4, the dump cylinder 17 has a flange 17 d attached to the hinge frame 4 with bolts 21 and is not rocked.
The non-oscillating dump cylinder 17 has an extension steel pipe 23 attached to the bottom side and a reduction steel pipe 25 attached to the rod side, and the steel pipes 23 and 25 attached to the hinge frame 4. The pressure oil is supplied and discharged.

For example, when the piston rod 17a is extended so that the roller 13 moves from the position P0 to the position P1, the dump cylinder 17 rotates the finger bar 5 with the support pin 69 of the hinge frame 4 as a fulcrum, and the fork 83 is moved as shown in FIG. It is rotated 35 degrees in the upward direction indicated by the alternate long and short dash line shown in FIG.
Further, when the piston rod 17a is contracted so that the roller 13 moves from the position P0 to the position P2, the dump cylinder 17 rotates the finger bar 5 with the support pin 69 of the hinge frame 4 as a fulcrum, and the fork 83 is moved as shown in FIG. It rotates 50 degrees in the downward direction indicated by the two-dot chain line shown in FIG.

In the above configuration, when loading with the fork 83, the operator supplies pressure oil to the dump cylinder 17 to extend or contract the piston rod 17a. The dump cylinder 17 applies rotational force to the cylinder plate 11 via the rail 15 and the roller 13 as the piston rod 17a expands and contracts.
Under this turning force, the cylinder plate 11 rotates the finger bar 5 with respect to the support pin 69 and rotates the fork 83 in the vertical direction. At this time, since the dump cylinder 17 is non-oscillating, the hinged fork can reduce the distance between the hinge frame 4 and the backrest 77 and the distance between the hinge frame 4 and the finger bar 5 as compared with the prior art. The arrangement position of can reduce the distance from the vehicle body. For this reason, the hinged fork can increase the allowable load weight because the loading position of the fork 83 is close to the vehicle body, and can shorten the longitudinal direction of the vehicle body, thereby improving the turning performance and stability.

  When the fork 83 loads, the operator places the finger plate 5a and the rod pin 13 on the right side in the left-right direction of the vehicle body, and between the cylinder plate 11 and the finger plate 5a on the left side. The front fork 83 is viewed from the gaps S1 and S2 shown in FIG. At this time, the cylinder plate 11 disposed at the center position of the vehicle body is formed by one piece, and the roller 13 and the rail 15 attached to the cylinder plate 11 are arranged on the opposite side of the eye point E. Therefore, the viewing angle Θ1 seen from the right-side gap S1 is larger than the conventional viewing angle Θ2, and the visibility is greatly improved.

  In FIG. 2 of the above embodiment, the dump cylinder 71 has its axis Sc inclined toward the rear of the vehicle body. However, as shown in FIG. 4, it may be attached perpendicularly to the vehicle body. Further, when the fork 83 is horizontal, the dump cylinder 17 has an arrangement position of the piston rod 17a between the position P0 and the position P1 where the roller 13 is displaced, and between the position P0 and the position P2. It is preferable that the length of the rail 13 is shortened and the difference in rotational force acting on the rail 13 during expansion and contraction is reduced.

It is a front view of the hinged fork device of the hinged fork according to the present invention. FIG. 2 is a side view of FIG. 1 according to the present invention. FIG. 2 is a plan view of FIG. 1 according to the present invention. It is a side view of the dump cylinder of the hinged fork device according to the present invention. It is an enlarged view of the rail and roller part which concern on this invention. It is a figure explaining the front view of the hinged fork device concerning the present invention. It is a front view of the hinged fork apparatus of a prior art example. It is a side view of FIG. 7 of a prior art example. It is a front view of FIG. 7 of a prior art example. It is a figure explaining the conventional front view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hinge fork device 4 ... Hinge frame 5 ... Finger bar 5a ... Finger plate 11 ... .... Cylinder plate 13 ... Rollers 15, 15A ... Rail 17 ... Dump cylinder 17a ... Piston rod 17d ... Flange 19 ... Trunnion 23, 25 ... Steel pipe 65 ... Mast device 69 ... Support pin 83 ... Fork E ...・ ・ ・ ・ ・ Eyepoint

Claims (5)

To the hinge frame that can be raised and lowered attached to the mast device of the hinged fork,
The finger bar connected to a dump cylinder connected at a substantially central position of the vehicle body is supported by a support pin disposed at a position spaced apart by a predetermined distance in the left-right direction of the vehicle body. The structure of the dump cylinder of the hinged fork that is rotatable with respect to the hinge frame by
The dump cylinder is almost perpendicular to the axis of the cylinder at the tip of the piston rod,
A hinged fork dump cylinder structure characterized in that a rail that engages with a roller rotatably attached to a finger bar is fixed.   The structure of the dump cylinder of the hinged fork according to claim 1, wherein the dump cylinder is attached to the hinge frame in a non-oscillating manner.   2. The structure of a dump cylinder for a hinged fork according to claim 1, wherein the rail has at least a U-shape facing and opening the cylinder plate of the finger bar.   The dump cylinder structure of a hinged fork according to claim 1, wherein the dump cylinder is connected to a steel pipe fixed to the hinge frame.   The hinged fork according to claim 1 or 3, wherein the rail is disposed on the opposite side of the eye point disposed in the left-right direction with respect to the cylinder plate of the finger bar from the center position of the vehicle body. Dump cylinder structure.

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