JP3852666B2 - Pulley and lift device for industrial vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pulley and a lift device for an industrial vehicle.
[0002]
[Prior art]
Some forklifts, which are industrial vehicles, perform work by attaching a front attachment to a lift device. In this case, in order to drive the front attachment, it is necessary to dispose hydraulic piping to the front attachment.
FIG. 9 is a front view of a lift device 50 of a three-stage mast type forklift, and shows a specification that can be fitted with a front attachment having two hydraulic actuators. Inside the pair of left and right outer masts 2, 2 mounted on the front part of the vehicle, a pair of left and right middle masts 3, 3 mounted so as to be movable up and down along the outer masts 2, 2 are mounted. A pair of left and right inner masts 4, 4 mounted so as to be movable up and down along the middle masts 3, 3 are mounted on the inside. A carriage 5 on which various attachments can be mounted is mounted on the inner masts 4 and 4 so as to be movable up and down along the inner masts 4 and 4.
[0003]
Behind the middle masts 3, 3 are disposed a pair of left and right lift cylinders 6, 6 that connect the lower parts of the outer masts 2, 2 and the upper parts of the middle masts 3, 3, respectively. In addition, pulleys 51 and 51 for chains are mounted on the rear surfaces of the upper portions of the middle masts 3 and 3 in a lateral direction (perpendicular to the longitudinal axis of the vehicle). Chains 8 and 8 having one end fixed to the upper part of outer masts 2 and 2 and the other end fixed to the lower part of inner masts 4 and 4 are wound around pulleys 51 and 51, respectively. Accordingly, the middle masts 3 and 3 are lifted along the outer masts 2 and 2 by extending the lift cylinders 6 and 6, and the inner masts 4 and 4 are also moved along the middle masts 3 and 3 through the chains 8 and 8. To rise.
A center cylinder 10 with chain pulleys 52 and 52 mounted on the left and right sides of the upper portion of the piston rod 11 (see FIG. 10) is erected at the lower center of the inner masts 4 and 4. Chains 13 and 13 having one end fixed to inner masts 4 and 4 and the other end fixed to carriage 5 are wound around pulleys 52 and 52, respectively. Accordingly, the carriage 5 is lifted along the inner masts 4 and 4 through the chains 13 and 13 by extending the center cylinder 10.
[0004]
This conventional example shows an example in which four pipes are provided as hydraulic pipes for a front attachment having two hydraulic actuators.
A hose pulley 53 is mounted coaxially with the chain pulley 51 behind the upper part of the left middle mast 3 (behind the chain pulley 51), and is located inside the upper part of the right middle mast 3. A hose pulley 54 is mounted vertically. Further, as shown in FIG. 10, double hose pulleys 55, 55 are mounted on the upper end of the piston rod 11 of the center cylinder 10. The pulleys 53, 54, 55, 55 for the respective hoses are pulleys for twin hoses (hose in which two rubber hoses are integrated), and the pulleys 7, 7 for the hoses attached to the middle masts 3, 3. The twin hoses 56 and 57 are respectively connected to the hose pulleys 55 and 55 attached to the center cylinder 10, and one end of each is connected to a front attachment pipe (not shown) of the carriage 5. 59 are wound. The twin hose 56 and the twin hose 58 are connected to a pipe (not shown) attached to the lower portions of the inner masts 4 and 4 and communicate with each other. Similarly, the twin hose 57 and the twin hose 59 are connected to a pipe (not shown) attached to the lower part of the inner masts 4 and 4 and communicate with each other.
Two of the four pipes from the vehicle body to the front attachment communicate with the front attachment pipe of the carriage 5 through the twin hoses 56 and 58 and the other two through the twin hoses 57 and 59. Thus, the driving operation of the front attachment becomes possible.
[0005]
[Problems to be solved by the invention]
However, the above prior art has the following problems.
Since the pulleys for the chain and the hose are individually provided, the number of pulleys is large and bulky. For this reason, the pulleys 55 and 55 attached to the upper end of the center cylinder 10 protrude above the center cylinder 10, and the protruding pulley and a part of the chain or hose wound around the pulley are used by the operator. This obstructs the field of view, and the operator's front field of view is only the R portion indicated by hatching in FIG.
Some front attachments require six or more hydraulic pipes depending on the type, and if a hose pulley is arranged in parallel to cope with this, the field of view will become narrower. There is also a method of providing a hose reel outside the outer mast 2 so as not to obstruct the field of vision, but providing a protrusion on the outside of the mast may hit the shelf etc., so that the operator concentrates on the work. This hinders work efficiency and is not preferable.
[0006]
In order to solve the above-described problems, the present invention provides a pulley capable of handling a small number of members to be wound and a lift device for an industrial vehicle capable of obtaining a good field of view using the pulley. The purpose is that.
[0007]
[Means, actions and effects for solving the problems]
In order to achieve the above object, the present invention is a pulley in which a first member to be wound is wound around a first groove with a bottom provided on the outer periphery, and a central portion is axially movable freely. A pulley that is pivotally supported on the bottom surface of the first groove , and a second groove around which the second member to be wound is wound is provided on the bottom surface of the first groove, and one side surface of the first groove is provided . And a first disk having one side surface and a bottom surface of the second groove and an extended surface of the bottom surface of the second groove, and a needle roller bearing mounted on the bottom surface of the second groove of the first disk And the other side surface of the first groove, the other side surface of the second groove, and a hole that can be fitted to an extended surface of the bottom surface of the second groove, and the needle roller bearing is mounted. And a second disk joined to the first disk .
Furthermore, a carriage that can be raised and lowered by expansion and contraction of the hydraulic cylinder through a chain that is wound around a pulley that is attached to the tip of the piston rod of the hydraulic cylinder, and an attachment that drives various attachments attached to the carriage are provided. A lift device for an industrial vehicle having a hose for supplying pressure oil from the vehicle body side to an actuator, wherein the pulley has either a first hung member as a chain or a hose, Ri Ah in the aforementioned pulleys and one of the rack members chain and hose, above the center cylinder erected between the left and right pair of inner masts provided with the pulley vertically, the chain and the hose, the forward It is characterized by being arranged so as to overlap the center cylinder as viewed from the top.
[0008]
According to the present invention, since the second groove is provided in the first groove of the pulley, the number of members to be wound that can be wound around one pulley can be increased, and the members to be wound are stacked and wound. Can be mounted. Thereby, in the apparatus which winds a several to-be-worn member, the number of pulleys can be reduced and the to-be-wound member can be arrange | positioned within a narrow width | variety.
Moreover, since the contact surface which supports the 1st to-be-wound member on both sides of the 2nd groove | channel is provided, even if there exists a 2nd groove | channel, the 1st to-be-wound member is supported stably. be able to.
Further, by providing a bearing in the first groove or the second groove, it is possible to absorb the slip generated due to the difference in the winding diameter between the first groove and the second groove. Can be prevented and durability can be improved.
Furthermore, by using the above pulleys for the lift device of an industrial vehicle to which various attachments are mounted, the number of pulleys used in the lift device can be reduced, the pulley mounting portion can be compactly accommodated, and the member to be wound Can be arranged within a narrow width. Thereby, the operator's front view can be ensured widely. Moreover, even if the number of winding members that need to be arranged increases depending on the type of attachment, an increase in the number of pulleys can be suppressed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment according to the present invention will be described in detail with reference to the drawings.
Some forklifts, which are industrial vehicles, perform work by attaching a front attachment to a lift device. In this case, in order to drive the front attachment, it is necessary to dispose hydraulic piping to the front attachment.
FIG. 1 is a front view of a lift device 1 of a three-stage mast type forklift, and shows a specification capable of mounting a front attachment having two hydraulic actuators.
Inside the pair of left and right outer masts 2, 2 mounted on the front part of the vehicle, a pair of left and right middle masts 3, 3 mounted so as to be movable up and down along the outer masts 2, 2 are mounted. A pair of left and right inner masts 4, 4 mounted so as to be movable up and down along the middle masts 3, 3 are mounted on the inside. A carriage 5 on which various attachments can be mounted is mounted on the inner masts 4 and 4 so as to be movable up and down along the inner masts 4 and 4.
[0010]
Behind the middle masts 3, 3 are disposed a pair of left and right lift cylinders 6, 6 that connect the lower parts of the outer masts 2, 2 and the upper parts of the middle masts 3, 3, respectively. Further, as shown in FIG. 3 which shows a plan view of the upper part of the mast, pulleys 7 and 7 for chains are laterally arranged on the rear surfaces of the upper parts of the middle masts 3 and 3 (perpendicular to the longitudinal axis of the vehicle). It is attached to. Chains 8 and 8 having one end fixed to the upper part of outer masts 2 and 2 and the other end fixed to the lower part of inner masts 4 and 4 are wound around pulleys 7 and 7, respectively. Accordingly, the middle masts 3 and 3 are lifted along the outer masts 2 and 2 by extending the lift cylinders 6 and 6, and the inner masts 4 and 4 are also moved along the middle masts 3 and 3 through the chains 8 and 8. To rise.
[0011]
A center cylinder 10 is erected at the center lower part of the inner masts 4, 4, and chain pulleys 12, 12 are vertically oriented at the upper end of the piston rod 11 of the center cylinder 10 (the axial center of the vehicle in the left-right direction). It is mounted in a direction perpendicular to Chains 13 and 13 having one end fixed to inner masts 4 and 4 and the other end fixed to carriage 5 are wound around pulleys 12 and 12, respectively. Accordingly, the carriage 5 is lifted along the inner masts 4 and 4 through the chains 13 and 13 by extending the center cylinder 10.
[0012]
In the present embodiment, as in the conventional example, an example in which four pipes are arranged as a hydraulic pipe for a front attachment having two hydraulic actuators is shown.
A pulley 14 for a twin hose (a hose in which two rubber hoses are integrally formed) is mounted in parallel with the pulley 7 in parallel behind the upper portion of the left middle mast 3 (behind the pulley 7). Further, as shown in FIG. 2, a twin hose pulley 15 is mounted between the chain pulleys 12 and 12 in parallel with the upper end of the piston rod 11 of the center cylinder 10. As will be described later, the chain pulleys 7, 7, 12, and 12 have a structure in which the chain and the hose can be wound together, and the hoses 16a, 16b, 17a, and 17b are wound around the pulleys. Twin hoses 18 and 19 are wound around the pulleys 14 and 15 for the twin hoses, respectively.
[0013]
One end of hoses 17 a, 17 b, 19 wound around pulleys 12, 12, 15 mounted on the center cylinder 10 is connected to a front attachment pipe (not shown) of the carriage 5, and the other end is a lower part of the inner mast 4. Is connected to a pipe (not shown) attached to the pipe. One end of hoses 16a, 16b, 18 wound around pulleys 7, 7, 14 mounted on middle masts 3, 3 are connected to four pipes (not shown) from the vehicle body to the front attachment. The other end is connected to the pipe attached to the lower part of the inner mast 4 and communicates with the hoses 17a, 17b and 19, respectively. That is, the four pipes from the vehicle main body to the front attachment communicate with the front attachment pipe of the carriage 5, thereby enabling the front attachment to be driven.
[0014]
Next, the structure of the pulley will be described with reference to FIG.
A bracket 22 having a shaft 21 is attached to the upper end of the piston rod 11 of the center cylinder 10. Then, pulleys 12, 15, 12 are attached to the shaft 21 in this order.
The pulley 15 is a twin hose pulley as described above, and has a groove having a substantially U-shaped cross section that supports the outer sides of the two hoses of the twin hose 19. It is mounted so that it can rotate freely.
[0015]
The pulley 12 is a pulley having a first groove A having a substantially trapezoidal cross section and a second groove B having a substantially rectangular cross section provided in the center of the first groove A. A needle roller bearing 12c is mounted on the bottom surface. The first groove A is slightly wider than the width of the chain 13 around which the first groove A is wound, and has support portions for the chain 13 on both sides of the upper end of the second groove B. The second groove B is slightly wider than the width of the needle roller bearing 12c to which the second groove B is mounted, and the depth is the sum of the thickness of the needle roller bearing 12c to be mounted and the diameter of the hose 17a to be wound. A little bigger than. Further, the pulley 12 is configured by joining two disks 12a and 12b having a split surface with a surface obtained by extending the bottom surface of the second groove B in one axial direction so that the needle roller bearing 12c can be mounted. ing. That is, the pulley 12 includes a disk 12a having one side surface of the first groove A, one side surface and bottom surface of the second groove B, and an extended surface of the bottom surface of the second groove B, and the first groove A. The needle roller bearing 12c is mounted on the disk 12a with a disk 12b having a hole that can be fitted to the other side surface of the second groove B, the other side surface of the second groove B, and an extended surface of the bottom surface of the second groove B. It joins later by methods, such as screwing, welding, and caulking. The pulley 12 is rotatably mounted on the shaft 21 via a bearing 12d integrally formed with the disk 12a.
[0016]
The twin hose pulley 14 attached to the left middle mast 3 has the same structure as the pulley 15 attached to the center cylinder 10, and the chain pulleys 7, 7 attached to the middle masts 3, 3 Is the same structure as the pulley 12 mounted on the center cylinder 10.
[0017]
According to this embodiment, since the pulley having the two-stage groove is employed, a plurality of pulleys can be wound around one pulley, and the total number of pulleys used in the lift device can be reduced. For this reason, the pulley mounting form above the center cylinder 10 can be made compact, and a wider field of view for the operator can be secured. In addition, since the chain and the hose are overlapped and wound by adopting a pulley having a two-stage groove, the hose and the chain to be wound are within the same width as the width of the center cylinder 10 in the center cylinder 10. Since the hose and the chain to be wound can be disposed behind the mast within the mast width on the mast side, it is possible to secure a wider field of view for the operator. Thereby, like the hatching portion S shown in FIG. 1, it is possible to ensure a wider front view of the operator as compared with the conventional case.
[0018]
Further, the needle roller bearing 12c mounted on the bottom surface of the second groove B can absorb the slip generated due to the difference in the winding diameter between the first groove A and the second groove B, thereby preventing wear. And durability can be improved.
Further, since the bottom surface of the first groove A has the support portions for the chain 13 on both sides of the upper end of the second groove B, the chain 13 can be stably supported.
[0019]
Next, a second embodiment according to the present invention will be described with reference to FIG. In addition, since only the form of a pulley differs from 1st Embodiment, description of the whole lift apparatus is abbreviate | omitted and demonstrates with the pulley structure of the center cylinder 10 upper end.
A bracket 26 having a shaft 25 facing in the left-right direction of the vehicle is attached to the upper end of the piston rod 11 of the center cylinder 10. Pulleys 27 and 27 are attached to the shaft 25 in parallel.
[0020]
The pulley 27 is a pulley having a first groove C having a substantially U-shaped cross section and a second groove D having a substantially rectangular cross section provided at the center of the first groove C. A needle roller bearing 27c is mounted on the bottom surface of. The first groove C has a substantially U-shaped cross section that supports the outer sides of the two hoses of the twin hose 28 to be wound. The second groove D is slightly wider than the width of the needle roller bearing 27c to which the second groove D is mounted, and the depth of the second groove D is the sum of the thickness of the needle roller bearing 27c to be mounted and the thickness of the chain 29 to be wound. A little bigger than. Further, the pulley 27 is configured by joining two disks 27a and 27b having a split surface with a surface obtained by extending the bottom surface of the second groove D in one axial direction so that the needle roller bearing 27c can be mounted. ing. That is, the pulley 27 includes a disk 27 a having one side surface of the first groove C, one side surface and bottom surface of the second groove D, and an extended surface of the bottom surface of the second groove D, and the first groove C. The needle roller bearing 27c is mounted on the disk 27a with a disk 27b having a hole that can be fitted to the other side surface of the second groove D, the other side surface of the second groove D, and an extended surface of the bottom surface of the second groove D. It joins later by methods, such as screwing, welding, and caulking. The pulley 27 is rotatably attached to the shaft 25 via a bearing 27d integrally formed with the disk 27a.
[0021]
According to the present embodiment, the same effects as those of the first embodiment can be obtained, and the effects superior to those of the first embodiment can be obtained as follows.
That is, since the twin hose 28 is wound around the first groove C of the pulley 27, the number of pulleys above the center cylinder 10 which is required in the first embodiment is two. be able to. Further, by attaching a mast-side pulley having the same structure, it is possible to correspond to the left and right masts with one pulley. Thereby, since the total number of pulleys can be reduced as compared with the case of the first embodiment, the pulley mounting form can be made more compact, and the operator's front field of view can be further secured.
[0022]
Depending on the type of front attachment, there may be three or more hydraulic actuators and the number of hydraulic pipes that need to be arranged may increase. However, pulleys as shown in FIGS. 5 and 6 may be used. That is, instead of the pulley 55 shown in FIG. 10, as shown in FIG. 5, the first groove E having a substantially U-shaped cross section around which the twin hose can be wound and the single groove E provided at the center of the first groove E A hose 33 can be wound around a pulley 31 having a second groove F having a substantially rectangular cross section, a twin hose 32 being wound around the first groove E, and a hose 33 being wound around the second groove F. May be. Further, instead of the pulley 27 shown in FIG. 4, as shown in FIG. 6, a first groove having a substantially U-shaped cross section on which a triple hose (a hose in which three rubber hoses are integrally formed in a row) can be wound. G and a pulley 35 having a second groove H having a substantially rectangular cross section in which a chain provided in the center of the first groove G can be wound, a triple hose 36 in the first groove G, a second The chain 37 may be wound around the groove H. According to this, even if the number of hydraulic pipes that need to be arranged increases, an increase in the number of pulleys can be suppressed, and deterioration of the operator's forward visibility can be suppressed. In addition, it is possible to cope without providing a hose reel outside the mast.
[0023]
Moreover, although the example which mounts the needle roller bearing for a slip absorption on the bottom face of the 2nd groove | channel has been demonstrated, as shown in FIG. If the pulley 39 having a structure having a protruding portion 39a capable of coming into contact with the roller 38a of the roller chain 38 is used on the bottom surface of the groove J, the needle roller bearing is not required, and the pulley 39 may be an integral part, which reduces the cost. Can be suppressed.
Furthermore, as shown in FIG. 8, a wire harness 41 may be wound around the second groove K of the pulley 40. The wire harness 41 is connected to an electrical component (such as a sensor or a light) attached to the carriage 5 or an attachment attached to the carriage 5, and includes, for example, a laser pointer indicating the position of the fork. Further, as shown in the figure, when the object to be wound is thin and the width of the second groove K may be narrow, the second groove K may be positioned at the end of the first groove L. In this case, the chain 42 wound around the first groove L is preferably a leaf chain so as to be stably supported by the first groove L.
[0024]
Further, for example, in the pulley 12, the bearing 12d has been described as being integrated with the disk 12a. However, it is needless to say that the bearing 12d may be provided separately.
Further, for example, in the pulley 12, the example in which the joining surface of the disk 12 a and the disk 12 b is an extended surface of the bottom surface of the second groove B has been described, but the second groove is concentric with the bottom surface of the second groove B. A cylindrical surface having a diameter slightly smaller than the diameter of the bottom surface of B may be used.
Moreover, although the example which mounts a needle roller bearing on the bottom face of the 2nd groove | channel was demonstrated, it is not limited to a needle roller bearing, For example, resin-made bushes etc. may be sufficient.
Moreover, although the mechanism which absorbs the slip which generate | occur | produces by the difference in the winding diameter of a 1st groove | channel and a 2nd groove | channel was provided in the 2nd groove side, you may provide in the 1st groove | channel side.
Further, the three-stage mast type lift device has been described. However, the vehicle may be applied to a pulley of a two-stage mast type lift device as long as the vehicle is equipped with a front attachment.
[0025]
As described above, according to the present invention, the number of pulleys in the entire apparatus can be reduced by using the pulley having the structure having the second groove in the first groove. Even if the number of hoses to be increased increases, the increase in the number of pulleys can be suppressed. For this reason, while being able to make a pulley mounting part compact, a hose and a chain can be piled up and wound, and when it employs for a lift device of a forklift, a operator's front field of view can be secured widely.
[Brief description of the drawings]
FIG. 1 is a front view of a lift device to which a first embodiment of the present invention is applied.
FIG. 2 is a cross-sectional view of the first embodiment of the present invention.
FIG. 3 is a plan view of the upper portion of the mast according to the first embodiment of the present invention.
FIG. 4 is a cross-sectional view of a second embodiment of the present invention.
FIG. 5 is a cross-sectional view of another aspect of an embodiment of the present invention.
FIG. 6 is a cross-sectional view of another aspect of the embodiment of the present invention.
FIG. 7 is a cross-sectional view of another aspect of the embodiment of the present invention.
FIG. 8 is a cross-sectional view of another aspect of an embodiment of the present invention.
FIG. 9 is a front view of a prior art lift device.
FIG. 10 is a cross-sectional view of the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Lift apparatus, 2 ... Outer mast, 3 ... Middle mast, 4 ... Inner mast, 5 ... Carriage, 6 ... Lift cylinder, 7, 12, 14, 15 ... Pulley, 8, 13 ... Chain, 10 ... Center cylinder, 16a, 16b, 17a, 17b ... hose, 18, 19 ... twin hose, A ... first groove, B ... second groove.

Claims (2)

A pulley in which a first member to be wound is wound around a bottomed first groove provided on the outer periphery, and a pulley having a central portion pivotally supported on a shaft so as to be freely rotatable,
A second groove around which the second member to be wound is wound is provided on the bottom surface of the first groove; and
A first disk having one side surface of the first groove, one side surface and a bottom surface of the second groove, and an extended surface of the bottom surface of the second groove;
A needle roller bearing mounted on the bottom surface of the second groove of the first disk;
The first groove has a hole that can be fitted to the other side surface of the first groove, the other side surface of the second groove, and an extended surface of the bottom surface of the second groove, and the needle roller bearing is attached to the hole. A second disk joined to the first disk;
Pulleys, characterized in that it comprises. A carriage that can be raised and lowered by expansion and contraction of the hydraulic cylinder through a chain wound on a pulley mounted on the tip of the piston rod of the hydraulic cylinder, and an actuator provided on an attachment that drives various attachments mounted on the carriage An industrial vehicle lift device having a hose for supplying pressure oil from the vehicle body side,
The pulley is a pulley according to claim 1, wherein the first member to be wound is one of a chain and a hose, and the second member to be wound is one of a chain and a hose .
An industrial vehicle characterized in that the pulley is provided vertically above a center cylinder standing between a pair of left and right inner masts, and the chain and the hose are arranged so as to overlap the center cylinder when viewed from the front. Lift device.

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