JP4391151B2 - Tilt structure of lifting carriage - Google Patents

Description

  The present invention relates to a tilt structure of a lift carriage in which a lift function of a forklift is added to the lift carriage itself of a forklift.

    As shown in FIG. 7 (a), the three-direction stacker forklift V raises two masts M at intervals in the vehicle width direction, and is lifted by a lifting carriage C supported by these masts M so as to be able to move up and down. As shown in FIG. 5B, the cargo handling fork F is rotated (rotated) so as to be lateral to the lifting carriage C, and the cargo handling fork F is moved (shifted) in the vehicle width direction together with the lifting carriage C. be able to.

The loading fork F can be tilted by inclining the mast M in the front-rear direction indicated by the arrow X. However, when the loading fork F is in the horizontal direction as described above, this tilting can be performed even if the mast M is inclined. Can not do. Therefore, as shown in FIG. 8, the loading fork F is joined to the rotating upright shaft R of the lifting carriage C with the upper end as a pivot fulcrum P, and the loading fork F is provided at the lower part of the lifting carriage C. Attempts are made to tilt directly in the direction indicated by the arrow Y. Techniques relating to this are disclosed in the following patent documents.
Japanese Utility Model Publication No. 55-172297

  The above three-way stacker forklift V needs to set a desired distance from the pivot fulcrum P to the operating point of the hydraulic cylinder H, so that the hydraulic cylinder H is positioned below the upright shaft R for rotation, that is, outside the lifting carriage C. Must be placed in. For this reason, it is inevitable that a hydraulic pipe for supplying pressure oil from a hydraulic pump (not shown in the figure) installed in the lifting carriage C to the hydraulic cylinder H is exposed to the outside of the lifting carriage C. There is a risk of being caught accidentally during the operation of the lifting carriage C. Further, since the large bending and deformation of the hydraulic piping accompanying the operation of the lifting carriage C are frequently repeated, for example, when a rubber hose is applied as the hydraulic piping, there is a problem that this life becomes extremely short.

  Furthermore, the portion of the hydraulic piping exposed from the lift carriage C needs to be loosened to some extent and bend gently so that the hydraulic piping can be freely bent and deformed. There is a problem that the hydraulic piping exposed in such a slack state hinders the visibility of the operator who has entered step S at the rear of the mast M.

  In view of the above-described problems, an object of the present invention is to provide a tilt structure of an elevating carriage in which hydraulic piping is built in the elevating carriage.

  The present invention relates to a rotating upright shaft that rotatably supports a fork on a horizontal plane, and a tilt horizontal shaft that is supported by the upright shaft and supports the rear end of the fork so that the front end of the fork is rotatable in the vertical direction. A carriage that includes a shaft, a hydraulic cylinder that is spaced apart from the horizontal shaft and supported by the upright shaft, and a hydraulic path that supplies pressure oil to the hydraulic cylinder, and tilts the fork by the hydraulic cylinder. The hydraulic path has a hydraulic line that supplies pressure oil to an end surface of the upright shaft, and has an opening on a circumferential surface extending in the axial direction from the end surface of the upright shaft. An in-axis path, a swivel pipe joint that connects the hydraulic line to the end surface of the upright shaft, and an off-axis line that connects one end to the opening of the in-axis path and connects the other end to the hydraulic cylinder. Preparation And wherein the Rukoto.

  Further, in the tilt structure of the lifting carriage according to the present invention, one path on the feed side or the return side of the hydraulic conduit is connected to the upper end surface of the upright shaft, and the other path is the lower end surface of the upright shaft. To the upright shaft, each extending from the upper end surface and the lower end surface to the middle in the axial direction, and forming two in-axis paths each opening an individual opening on the circumferential surface in the axial direction, The openings of the two in-axis paths are respectively connected to the feed-side port and the return-side port of the hydraulic cylinder through the two off-axis pipe lines.

  Further, in the tilt structure of the lifting carriage according to the present invention, the cargo handling fork includes a hanging portion that extends downward from the rear end of the fork and a load receiving portion that extends from the hanging portion to the tip of the fork, and the fork rear end is the A U-shaped support frame that is supported between both ends of the horizontal shaft and that has the upper ends of a pair of arm portions as bearing portions and the lower ends are connected by a swinging piece, and the bearing portions are connected to the horizontal shaft. The swing piece is suspended below the horizontal shaft, and the swing piece is brought into contact with the hanging portion of the cargo handling fork from the opposite side of the load receiving portion; However, the swinging piece is pressed against a hanging portion of the cargo handling fork.

  According to the tilt structure of the elevating carriage according to the present invention, the hydraulic line that supplies the hydraulic pressure to the end surface of the upright shaft is connected to the in-axis path of the upright shaft via the swivel joint, so that the hydraulic path is configured. The upright shaft can be freely rotated with respect to the hydraulic pipe line while securely connecting the hydraulic pipe line, the swivel pipe joint, the in-axis path, and the off-axis path. In addition, since the hydraulic cylinder coupled to the upright shaft rotates together with the upright shaft, the off-axis pipe line connecting the opening of the peripheral surface of the upright shaft and the hydraulic cylinder is connected to the upright shaft and the hydraulic cylinder. On the other hand, it remains stationary, and the off-axis pipe line is not bent or deformed.

  Accordingly, for example, a steel pipe having a lower expansion coefficient than that of a rubber hoe can be applied as the off-axis pipe line, thereby minimizing pressure loss in the hydraulic path. Alternatively, even when a rubber hose is applied as an off-axis pipe line, the deterioration does not proceed due to frequent deformation of the rubber hose, so that the frequency and location of maintenance related to the lifting carriage can be reduced.

  Further, there are few places where the hydraulic path is exposed to the outside of the carriage, and the hydraulic path does not protrude significantly from the lifting carriage. For this reason, there is no possibility that the hydraulic path is caught by luggage or the like during the operation of the lifting carriage. In addition, the hydraulic path hardly enters the field of view of the operator who operates the rear of the lifting carriage. Therefore, the operator can concentrate on the cargo handling work.

  Furthermore, according to the tilt structure of the lifting carriage according to the present invention, one hydraulic conduit is connected to the upper end surface of the upright shaft, and the other hydraulic conduit is connected to the lower end surface of the upright shaft, and these are connected to the upright shaft. Since it is connected to the feed-side port and the return-side port of the hydraulic cylinder via two in-axis paths and two off-axis pipe lines, the hydraulic cylinder actuating rod is connected to the hydraulic compression force. Can be driven. Therefore, the advancing / retreating operation of the operating rod can be speeded up, and the smooth operation of the hydraulic cylinder can be maintained even when a large load is applied to the operating rod.

  Further, in the tilt structure of the lifting carriage according to the present invention, the rear end of the fork of the cargo handling fork is supported between both ends of the horizontal shaft, and a pair of arms of the U-shaped support frame are rotated at both ends of the horizontal shaft. The swinging piece that hangs downward from the horizontal axis in a state where it is freely connected is configured to be pressed against the hanging portion of the loading fork by a hydraulic cylinder, and the loading fork is tilted by this pressing force.

  Accordingly, it is possible to simultaneously press the hanging portion of the cargo handling fork by one hydraulic cylinder arranged directly below the upright shaft. In this case, since only the horizontal shaft and the handling fork are located on both sides of the lifting carriage, there is almost nothing obstructing the field of view of the operator who steers it behind the lifting carriage, and the operator's field of view is further improved. . Moreover, when the tilting operation of the cargo handling fork is provided by only one hydraulic cylinder as described above, the weight of the lifting carriage itself can be reduced by reducing the number of heavy objects in the lifting carriage parts group.

  As shown in FIGS. 1 and 2, the tilt structure 1 of the elevating carriage according to the present embodiment includes a rotating upright shaft 3 that rotatably supports a loading fork 2, and a fork of the loading fork 2 on the upright shaft 3. A tilting horizontal shaft 4 that rotatably supports the rear end 20, a hydraulic cylinder 6 that is spaced downward from the horizontal shaft 4 and is coupled to the upright shaft 3 via a T-shaped bracket 5, and a hydraulic cylinder 6 is provided with a hydraulic path 7 for supplying pressure oil to 6. The hydraulic cylinder 6 tilts the loading fork 2 by rotating the loading fork 2 in the direction in which the fork tip 21 moves up and down with the horizontal shaft 4 as a fulcrum.

  The hydraulic path 7 extends from the end surfaces 30 and 31 of the upright shaft 3 to the middle of the axial direction indicated by the arrow Z from the end surfaces 30 and 31 of the upright shaft 3 in the coaxial direction. In-shaft paths 12 and 13 having openings 10 and 11 opened on the middle peripheral surface, swivel pipe joints 14 and 15 respectively connecting the hydraulic pipe lines 8 and 9 to the in-axis paths 12 and 13 of the upright shaft 3, and shafts It is composed of off-axis pipe lines 16 and 17 having one end connected to the openings 10 and 11 of the inner paths 12 and 13 and the other end connected to the hydraulic cylinder 6 respectively.

  Here, “connection” means that the joints of pipes or paths are joined together using a well-known pipe joint or by welding or the like, unless otherwise specified. Further, as the swivel pipe joints 14 and 15, a well-known 360 ° freely rotatable pipe joint can be applied.

  The main body of the tilt structure 1 is engaged with a mast 101 raised on a forklift chassis or the like via a plurality of rollers 102 so as to be movable in the vertical direction. The base portion 103 fixes a pair of horizontal rails 104 extending in the vehicle width direction, and further fixes two rack gears 105 extending in the vehicle width direction to the pair of horizontal rails 104, respectively. On the other hand, a plurality of groove portions 106 are formed in each of the pair of horizontal rails 104. Rollers (same reference numerals) are engaged in these groove portions 106, and the head portion 107 is attached to the base portion 103 through the rollers so as to be movable in the vehicle width direction.

  The head unit 107 includes a main shaft 109 provided with a pair of pinions 108 that mesh with the two rack gears 105, a first hydraulic motor 110 that engages an output shaft pinion 119 with one of the pair of pinions 108, and an upright shaft. 3 is provided with a second hydraulic motor 112 that applies a rotational force via a gear train 111. These first and second hydraulic motors 110 and 112 are connected to a manifold 113 common to the hydraulic path 7. The manifold 113 is supplied with hydraulic pressure via a main supply pipe 70 from a hydraulic pressure generating unit that is on the left side in the figure and does not appear in the figure. This hydraulic pressure generating unit is a well-known device comprising a hydraulic pump, a reservoir tank, a directional control valve, and piping connecting them together.

  The shifting operation of the cargo handling fork 2 can be performed by starting the first hydraulic motor 110 and causing the head portion 107 to travel in the vehicle width direction. The rotating operation of the loading fork 2 starts the second hydraulic motor 112 to rotate the upright shaft 3, and the T bracket 5, the hydraulic cylinder 6, and the loading fork are rotated along with the rotation of the upright shaft 3. This can be done by turning the two together.

  One hydraulic line 8 is connected to an end face (hereinafter referred to as “upper end face”) 30 facing upward of the upright shaft 3. The other hydraulic pipe 9 is rotatably connected to an end face (hereinafter referred to as “lower end face”) 31 facing downward of the upright shaft 3 via swivel joints 14 and 15. These two hydraulic pipes 8 and 9 are steel pipes that alternately carry the feed-side or return-side paths, respectively.

  That is, when hydraulic pressure is supplied from the manifold 113 to the feed-side port 60 of the hydraulic cylinder 6 through the one hydraulic line 8, the operating rod 61 of the hydraulic cylinder 6 moves forward toward the cargo handling fork 2. The hydraulic oil is discharged from the return side port 62 of the hydraulic cylinder 6 to the other hydraulic line 9. On the contrary, when the hydraulic pressure is supplied from the manifold 113 to the return side port 62 of the hydraulic cylinder 6 through the other hydraulic pipe 9, the return of the hydraulic cylinder 6 is performed at the same time as the operating rod 61 moves backward from the cargo handling fork 2. The hydraulic oil is discharged from the side port 62 to the other hydraulic line 9.

  The in-axis paths 12 and 13 are individual paths that are divided in the middle of the upright shaft 3 in the axial direction. Specifically, as shown in FIG. 3, the upright shaft 3 extends from the upper end surface 30 to the middle in the axial direction below the upper end surface 30, and forms an in-axis path 12 having an opening 10 on the circumferential surface in the middle of the coaxial direction. . Further, the upright shaft 3 extends from the lower end surface 31 to the middle in the axial direction above it, and forms an in-axis path 13 having an opening 11 on the circumferential surface in the middle of the coaxial direction. A plane portion 32 is formed at a location on the peripheral surface of the upright shaft 3 toward the cargo handling fork 2, and a plurality of screw holes 33 are formed at appropriate positions on the plane portion 32.

  As shown in FIGS. 4 and 5, the T-shaped bracket 5 is a substantially T-shaped structure in which a plurality of pieces of steel plates or steel strips are joined together by welding or the like. The horizontal shaft 4 is supported at the corresponding positions of the end plates 51 at both ends of the horizontal extension portion 50 and the pair of support flange portions 52 extending downward from the horizontal extension portion 50. Each bearing hole 53 is formed. A front plate portion 54 is spanned between the pair of support flange portions 52. The front plate portion 54 is in close contact with the flat surface portion 32 of the upright shaft 3 on the opposite surface shown in FIG. A screw insertion hole 55 is drilled at a position corresponding to the screw hole 33 in the front plate portion 54. The T-bracket 5 is fixed to the upright shaft 3 by inserting the bolt 56 shown in FIG. 1 into the screw insertion hole 55 and tightening the bolt 56 into the screw hole 33 of the upright shaft 3.

  The pair of support flange portions 52 extend a pair of cover pieces 57 below each of them, and the hydraulic cylinder 6 can be accommodated in a holder portion 58 between the pair of cover pieces 57. Although not shown in detail in the drawing, the holder portion 58 includes a mount for positioning and fixing the hydraulic cylinder 6 therein. The holder portion 58 illustrated in FIG. 5 is opened downward in consideration of maintenance related to the hydraulic cylinder 6, but as shown in FIG. 4, the lower surface of the holder portion 58 is closed to conceal the hydraulic cylinder 6. You may do it.

  As shown in FIGS. 1 and 2, the cargo handling fork 2 includes a hanging portion 22 extending downward from the fork rear end 20 and a load receiving portion 23 extending from the hanging portion 22 to the fork tip 21 as a whole. The shape is substantially L-shaped. A steel pipe (same reference numeral) is welded to the fork rear end 20, and the fork rear end 20 is rotatably supported by the horizontal shaft 4 in a state where the horizontal shaft 4 is inserted into the steel pipe. Further, as shown in FIG. 4, the carriage structure 1 has upper ends of the pair of arm portions 180 as bearing portions 181 that can be rotatably inserted at both ends of the horizontal shaft 4. A U-shaped support frame 18 is provided which is connected by a swing piece 182 extending in the vehicle width direction.

  As described above, the swing piece 182 is suspended below the horizontal shaft 4 while the upper ends of the pair of arm portions 180 are pivotally connected to both ends 40 of the horizontal shaft 4, and the cargo handling fork 2 Is in contact with the hanging portion 22 from the opposite side of the load receiving portion 23. The height position of the swing piece 182 matches the height of the operating rod 61 of the hydraulic cylinder 6 that is disposed one machine directly below the upright shaft 3.

  When the hydraulic cylinder 6 advances the operating rod 61, the operating rod 61 applies a force to the hanging portion 22 of the cargo handling fork 2 via the swing piece 182 in a direction in which the operating rod 61 is pressed toward the fork tip 21 side. As a result, the cargo handling fork 2 assumes an inclined posture in which the fork tip 21 is raised with the horizontal shaft 4 as a fulcrum. On the other hand, when the hydraulic cylinder 6 retracts the operating rod 61, the above force is removed, so that the cargo handling fork 2 has an inclined posture in which the fork tip 20 is lowered by its own weight. The 18 swing pieces 182 are also pushed back.

  In the above description, the actuating rod 61, the swing piece 182 and the hanging portion 22 are simply brought into contact, but these contacts may be pin-joined. Thereby, even when the cargo handling fork 2 rotates in any of the above directions, the cargo handling fork 2 can be forcibly driven in accordance with the forward and backward movement of the operating rod 61. FIG. 4 shows four cargo handling forks 2. This is because the position of the cargo handling fork 2 can be slid along the horizontal axis 4 by removing the pin 24 from the upper part of the rear end 20 of the fork. It suggests. In addition, the present invention can be implemented in a mode in which various improvements, modifications, and variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

  For example, the hydraulic line 9, the in-axis path 13, the swivel pipe joint 15, and the off-axis pipe line 17 are omitted, and the hydraulic line 8, the in-axis path 12, the swivel pipe joint 14, and the off-axis pipe line 16 are omitted. When the operating rod 61 of the hydraulic cylinder 6 is moved forward by the hydraulic pressure supplied from the hydraulic pressure generation unit via the hydraulic path 7 consisting of the following, and when the operating rod 61 is moved backward, the operating rod 61 is moved by the load of the cargo handling fork 2. It is configured to push back inward, and the hydraulic oil discharged from the hydraulic cylinder 6 in this process may be returned to the hydraulic pressure generating unit via the same hydraulic path 7 again. That is, it is not always necessary to provide two hydraulic paths 7 for each hydraulic cylinder 6, and such a simple configuration contributes to further simplification of the lift carriage structure 1.

  FIG. 6 conceptually shows an example in which the elevating carriage structure 1 is applied to a widely used forklift. Reference numeral 500 in the figure is a part corresponding to the T-shaped bracket 5 and is a pack plate mainly composed of a single iron plate. In addition to being heavy compared to the T-shaped bracket 5 described above, there are some restrictions in that the field of view of the operator is slightly blocked. However, the existing upright shaft 3 is appropriately perforated, and the pack plate 500 There is an advantage that the hydraulic path 7 can be configured very simply by simply piping the off-axis pipe lines 16 and 17 along the surface of the pipe.

Sectional drawing of the tilt structure of the raising / lowering carriage which concerns on embodiment of this invention. Sectional drawing of the principal part of the tilt structure of the raising / lowering carriage which concerns on embodiment of this invention. The side view of the rotation axis | shaft applied to the tilt structure of the raising / lowering carriage which concerns on embodiment of this invention. The rear view of the principal part of the tilt structure of the raising / lowering carriage which concerns on embodiment of this invention. The perspective view of the support body applied to the tilt structure of the raising / lowering carriage which concerns on embodiment of this invention. Sectional drawing which shows the other example of the tilt structure of the raising / lowering carriage which concerns on embodiment of this invention. The side view of the forklift carrying the conventional raising / lowering carriage, and the perspective view of the principal part. The side view which shows the detail of d section of FIG.

Explanation of symbols

1: Tilt structure 2: Handling fork 3: Standing shaft 4: Horizontal shaft 6: Hydraulic cylinder 7: Hydraulic path 8, 9: Hydraulic pipe 10, 11: Opening 12, 13: In-shaft path 14, 15: Swivel fitting 16, 17: Off-axis pipe line 18: U-shaped support frame 20: Fork rear end 21: Fork front end 22: Hanging part 23: Load receiving part 30, 31: End face 40: Both ends 180: Arm part 181: Bearing part 182: Swing Moving piece

Claims (3)

A rotating upright shaft for pivotally supporting the fork on a horizontal plane, a tilting horizontal shaft supported on the upright shaft and supporting the rear end of the fork so that the front end of the fork is rotatable in the vertical direction; and A carriage tilt structure comprising: a hydraulic cylinder disposed apart from a horizontal axis and supported by the upright axis; and a hydraulic path for supplying pressure oil to the hydraulic cylinder, wherein the fork is tilted by the hydraulic cylinder. ,
A hydraulic pipe for supplying pressure oil to the end face of the upright shaft, an in-shaft path extending from the end face of the upright shaft to the middle in the axial direction, and having an opening in the circumferential surface in the middle of the axial direction; A swivel pipe joint that connects the hydraulic pipe line to an end surface of the upright shaft, and an off-axis pipe line that connects one end to the opening of the in-axis path and connects the other end to the hydraulic cylinder. Tilt structure of the lifting carriage. One path on the feed side or the return side of the hydraulic line is connected to the upper end surface of the upright shaft, and the other path is connected to the lower end surface of the upright shaft,
Forming two in-axis paths that extend from the upper end surface and the lower end surface to the middle in the axial direction on the upright shaft and open individual openings on the circumferential surface in the middle of the axial direction;
The openings of the two in-axis paths are respectively connected to the feed-side port and the return-side port of the hydraulic cylinder through the two off-axis pipe lines, respectively. The tilt structure of the lifting carriage as described. The cargo handling fork includes a hanging portion extending downward from the rear end of the fork and a load receiving portion extending from the hanging portion to the tip of the fork, and the fork rear end is supported between both ends of the horizontal shaft,
U-shaped support frames formed by connecting the upper ends of a pair of arm portions with bearing portions and swinging pieces between the respective lower ends, and connecting the bearing portions to both ends of the horizontal shaft, respectively, The swing piece is suspended below the horizontal shaft, and the swing piece is brought into contact with the hanging portion of the cargo handling fork from the opposite side of the load receiving portion,
The tilt structure of the elevating carriage according to claim 1, wherein the hydraulic cylinder presses the swinging piece against a hanging portion of the cargo handling fork.

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