JP5090033B2 - Aerial work platform - Google Patents

Description

  The present invention relates to an aerial work vehicle.

  Conventionally, as an aerial work platform for moving workers and luggage to a desired height, a work table is provided on the chassis via a scissor link, and the scissor link is opened and closed by an extension cylinder. There is known one configured to raise and lower a workbench. In this type of aerial work vehicle, after the vehicle body has traveled to a position below the target position, work such as loading at a high place can be performed by raising the work table (for example, (See Patent Documents 1 and 2).

  For example, in an aerial work vehicle described in Patent Document 1, the scissor link mechanism is configured by two upper and lower links, and a roller that moves along the guide rail of the work table is attached to the upper end of the upper link, Has been made. The lower link has a lower end pivotally supported on the base to be a pivot end, and the other lower end is a moving end that moves along the guide rail of the base.

  Further, depending on the work contents, it may be necessary to move the work table up and down horizontally after raising the work table. In view of this, in the above-described example of an aerial work vehicle, a technique has been proposed in which a rail is provided between the work table and the work table holding member so that the work table can be slid in the front-rear direction using an appropriate hydraulic cylinder. .

  FIG. 4 shows the arrangement relationship between the hydraulic cylinder 120, the shaft 130, and the scissor link (roller) 140 provided on the bottom surface side of the work table 110 in this type of aerial work vehicle. It is explanatory drawing compared by.

  In the illustrated aerial work vehicle, the shaft 130 is connected to a roller provided on the upper link 140. The hydraulic cylinder 120 is disposed on the bottom surface of the work table 110 via a support member, and the tip of the piston rod 121 is connected to the shaft 130.

In this case, as shown in FIG. 4A, the hydraulic cylinder 120 extends when the work table 110 is raised (before moving horizontally), and extends from the cylinder tube 122 to the piston rod 121. Is disposed in an exposed state. As shown in FIG. 4B, when the hydraulic cylinder 120 is contracted and horizontally moved to the work position of the work table 110, the piston rod 121 is inserted into the cylinder tube 122, and the work table 110 is It is configured to move forward with respect to the link 140.
Japanese Utility Model Publication No. 5-89396 JP 2005-231874 A

  When the connecting structure of the hydraulic cylinder 120 as in the conventional example is adopted, when the work table 110 is moved horizontally from the standby position to the work position, the cylinder tube 122 of the hydraulic cylinder 120 is connected to the scissor link 140 on the bottom surface of the work table 110. Will move against. For this reason, the oil supply line such as a hydraulic pipe or a hydraulic hose connected to the cylinder tube 122 needs to be played, and the oil supply line must be arranged so as not to interfere when the cylinder tube 122 moves. It was. If it does so, there existed a problem that routing of piping became complicated and piping work became complicated.

  Further, as shown in FIG. 4A, since the piston rod 121 is always exposed from the cylinder tube 122 when the work table 110 is in the standby position, dust, dust, and the like are likely to adhere to the piston rod 121 and slide. There was a risk of scratching the moving surface. For this reason, wear of the seal packing is accelerated, and the sealing effect is easily lost or oil leakage is likely to occur, which is not preferable. In addition, since the hydraulic cylinder 120 extends at the standby position of the work table 110 and contracts at the work position, there is a limit in securing a cylinder stroke, and there is a disadvantage that a sufficient stroke cannot be obtained.

  Further, due to the structure of the hydraulic cylinder 120, there is a disadvantage that the movement width of the center of gravity of the work table 110 becomes large due to the horizontal movement of the work table 110. Thus, when the movement width of the center of gravity of the work table 110 becomes large, the work table 110 becomes unstable with respect to the scissor link, and there is a possibility that stability against wind pressure and workability on the work table 110 may be reduced. . Also, considering the convenience and versatility of work using an aerial work vehicle, it was desirable to be able to ensure a greater horizontal movement distance of the workbench 110.

  Accordingly, the present invention has been made in view of the above-described problems, and ensures stability when the work table is raised, and maintains a good operation of the hydraulic cylinder so that the work table is leveled. It is intended to provide an aerial work vehicle that can move smoothly. Another object of the present invention is to increase the degree of freedom in designing such an aerial work vehicle and to efficiently and easily assemble a structure that increases the coupling rigidity between a hydraulic cylinder and a shaft.

In order to achieve the above-described object, the present invention provides an aerial work vehicle in which a scissor link mechanism is disposed between a chassis and a work table, and the work table is moved up and down between the chassis and a height by the scissor link mechanism. A roller provided rotatably at the upper end of the scissor link mechanism is rotatably disposed in a guide rail extending in the front-rear direction on the bottom surface of the work table. The bottom surface of the work table is parallel to the guide rail. the hydraulic cylinder is provided, the hydraulic cylinder with a piston rod is connected to the worktable, the cylinder tube is coupled to the shaft of the roller, both sides of the rod end of the cylinder tube of the hydraulic cylinder shaft of the left and right rollers are respectively connected to, is advanced with the platform in a high place by the extending action of the hydraulic cylinder to the working position from the standby position It is characterized by a door.

  According to this configuration, when the work table is at the standby position, the hydraulic cylinder is in a contracted state, and the piston rod is inserted into the cylinder tube. Usually, since the time left in the standby position is longer than the working position, the chance of dust and the like adhering to the piston rod is reduced, and the hydraulic cylinder can be used in a good condition for a long time. Further, in this configuration, even if the work table is moved forward, only the piston rod connected to the work table moves in the hydraulic cylinder. It is also possible to increase the stability. In addition, since the cylinder tube does not move at this time, handling of the hydraulic piping and the like is simplified, and piping work can be facilitated.

In addition, since the left and right roller shafts are connected to both ends of the rod end of the cylinder tube of the hydraulic cylinder, the cylinder stroke of the hydraulic cylinder is ensured by an amount corresponding to the length of the cylinder tube. It is possible to increase the degree of freedom of design by increasing the movable length of the work table.

  Also, the inner ends of the shafts of the left and right rollers are attached to and removed from the bearing portions formed on the left and right sides of the bearing trunnion provided at the rod end of the cylinder tube of the hydraulic cylinder. It may be fitted and supported by a free split bearing.

  As a result, the bearing trunnion and the split bearing can be easily assembled to the shaft, and the coupling rigidity with the shaft can be improved.

  According to the aerial work vehicle of the present invention configured as described above, the stability when the work table is raised is ensured, and the hydraulic cylinder is maintained in good operation, and the work table is kept horizontal for a long time. It becomes possible to move smoothly. Furthermore, it is possible to increase the degree of design freedom for the horizontal movement of the workbench and to efficiently and easily assemble a structure that increases the coupling rigidity between the hydraulic cylinder and the shaft.

  The best mode for carrying out an aerial work vehicle according to the present invention will be described below with reference to the drawings.

  1 to 3 show an example of an aerial work vehicle according to the present invention. FIG. 1 is a side view of the aerial work vehicle, and FIG. 2 shows a partially omitted aerial work vehicle in FIG. AA sectional view, FIG. 3 is explanatory drawing which shows the bottom face side of a work bench | platform.

  In the following description, the direction in which the cab 2 is located is the front, and the up, down, left, and right directions are directions viewed from the driver. Further, in FIG. 2, in order to make the drawing easier to see, hatching indicating a cross section is omitted from each component member.

  The aerial work vehicle 1 in the illustrated form is a truck that is used at an airport or the like and is used to mount an in-flight meal or the like in an aircraft. The aerial work vehicle 1 is provided with a self-propelled chassis 3 having a driver's cab 2 in front, a scissor link mechanism 4 extending in the front-rear direction on the chassis 3, and the scissor link mechanism 4. And a work table (container) 6 provided.

  The scissor link mechanism 4 includes two inner links 41 arranged in parallel on the left and right sides, two outer links 42 arranged in parallel on the left and right sides, a link shaft 43 that connects these links 41 and 42 in an X shape, and is openable and closable. And a hydraulic lift cylinder 44 mounted between 41 and 42.

  The inner links 41 are integrally connected to each other in the vicinity of the upper ends of the inner links 41 by a shaft (front shaft) 51, and the lower ends thereof are supported so as to be movable along the chassis frame 31. In the outer link 42, the vicinity of the upper ends of the outer links 42 are integrally connected by a shaft (rear shaft) 52, and the lower ends of the outer links 42 are rotatably fixed to the chassis frame 31.

  Further, these shafts 51 and 52 are respectively spanned in a rectangular work table frame 61 that holds the work table 6, so that the scissor link mechanism 4 can be expanded and contracted via a hydraulic lift cylinder 44. The work table 6 can be moved up and down freely while being maintained parallel to the chassis 3.

  In this embodiment, a work table frame 61 is provided on the bottom surface side of the work table 6, and a roller 62 and a guide rail 63 are provided. The roller 62 is rotatably provided at the upper ends of the links 41 and 42 of the scissor link mechanism 4. Each roller 62 and the links 41 and 42 are connected through shafts 51 and 52, respectively. Specifically, each roller 62 is rotatably attached to one end of each of the shafts 51 and 52. As shown in FIG. 2, the shaft 51 is rotatably inserted into a cylindrical bush 53, and the upper end portion of the inner link 41 is welded to the bush 53.

  The guide rail 63 is disposed in the front-rear direction along the work table frame 61 on the bottom surface of the work table 6. The roller 62 is disposed on the guide rail 63 and is guided by the guide rail 63 so as to be movable in the front-rear direction of the work table 6 (that is, the work table 6 is movable with respect to the scissor link mechanism 4). ).

  As shown in FIG. 2, a hydraulic cylinder 7 is disposed on the bottom surface of the work table 6 in parallel with the guide rail 63. In the hydraulic cylinder 7, a piston rod 72 is fitted and inserted into a cylindrical cylinder tube 71, and the piston rod 72 can be slid and expanded by supplying and discharging pressure oil.

  The hydraulic cylinder 7 disposed on the bottom surface of the work table 6 is disposed such that the front end side of the piston rod 72 is positioned forward, and the front end portion of the piston rod 72 is supported on the bottom surface of the work table 6 (not shown). It is connected via a member. The shaft 51 of the roller 62 is connected to the cylinder tube 71 into which the piston rod 72 is inserted. In particular, in the present invention, the front shaft 51 is connected to the rod side end of the cylinder tube 71. The cylinder tube 71 is provided with a suspension member (not shown), and a projecting fitting portion provided on the suspension member is fitted in a suspension groove portion (not shown) of the work table frame 61 so as to be movable back and forth. It comes to match. Accordingly, the cylinder tube 71 is suspended from the work table frame 61 so as to be movable back and forth.

  With this configuration, the aerial work vehicle 1 is moved horizontally from the standby position indicated by the one-dot chain line in FIG. 1 to the operation position indicated by the solid line by the hydraulic cylinder 7 extending. It is possible to move forward in the direction.

  That is, as shown in FIG. 3A, when the work table 6 is in the standby position, the hydraulic cylinder 7 is reduced, and the piston rod 72 fixed to the bottom surface of the work table 6 is inserted into the cylinder tube 71. ing.

  On the other hand, when the work table 6 is moved horizontally, the work table 6 is moved to an appropriate work position by extending the hydraulic cylinder 7 as shown in FIG.

  In this case, the cylinder tube 71 into which the piston rod 72 is inserted is moved rearward relative to the work table 6, but is not moved relative to the scissor link mechanism 4. Therefore, even if the work table 6 is moved from the standby position to the work position, it is not necessary to move the relatively heavy cylinder tube 71, so that the movement of the center of gravity in the hydraulic cylinder 7 can be suppressed to be extremely small. Further, it is not necessary to play an oil supply line such as a hydraulic pipe attached to the cylinder tube 71, and the fixing work can be facilitated with a simple pipe.

  Further, in the illustrated embodiment, the shaft 51 connected to the hydraulic cylinder 7 is constituted by a bearing trunnion 81 provided at the rod side end of the cylinder tube 71 and a split bearing 82 detachably attached to the bearing trunnion 81. It is supported.

  As shown in FIG. 2, the bearing trunnion 81 has bearing portions 81a and 81a on both the left and right sides, and a recess for fitting and supporting the end portion of the shaft 51 is formed by the bearing portion 81a and the split bearing 82. ing. The bearing trunnion 81 and the split bearing 82 are integrated by fastening a bolt 83.

  As a result, the coupling rigidity of the shaft 51 to the hydraulic cylinder 7 can be improved by the fastening force of the bolt 83, and the shaft 51 can be tightened between the bearing trunnion 81 and the split bearing 82 without a gap. That is, the hydraulic cylinder 7 and the shaft 51 are integrated so that the shaft 51 does not rotate.

  In this embodiment, the shaft 51 is separated at the center. The inner ends of these shafts 51, 51 are fitted and supported in the recesses formed by the bearing portions 81a, 81a formed on the left and right sides of the bearing trunnion 81 and the split bearings 82, 82, respectively. It has become. For this reason, the shafts 51 and 51 can be aligned at the same time and the shaft 51 can be positioned with respect to the cylinder tube 71 at the time of assembly.

  Therefore, after the roller 62 is disposed on the guide rail 63 of the worktable frame 61, the hydraulic cylinder 7 is disposed in a direction orthogonal to the shafts 51, 51 connected to the upper end portion of the link 41. If the bearing trunnion 81 is fitted to the end of the shaft from above, the split bearing 82 is fitted from below and fastened with the bolt 83, the assembly can be easily performed.

  In the aerial work vehicle 1 configured as described above, as shown in FIG. 1, the hydraulic cylinder is set at the standby position in a state where the scissor link mechanism 4 is extended and the work table 6 is lifted from the vehicle table 3. 7 is a reduced state, and since the piston rod 72 is fitted and inserted into the cylinder tube 71, it is possible to prevent dust and dust from adhering to the piston rod 72 and cause damage to the sliding surface to cause oil leakage. Etc. can be prevented.

  Then, when it is necessary to move the work table 6 in the front-rear direction after raising the work table 6, the work table 6 is moved to the scissor link mechanism 4 by extending the hydraulic cylinder 7. 6 can be moved horizontally to advance to the working position.

  In addition, the hydraulic cylinder 7 having the above-described connection structure can increase the cylinder stroke associated with the horizontal movement of the work table 6. That is, in the illustrated embodiment, it is possible to select a hydraulic cylinder 7 having a long cylinder tube 71, and the cylinder stroke can be secured by the length of the cylinder tube 71, increasing the degree of freedom in design. be able to.

  In the above description, this embodiment is merely an example of the present invention, and the present invention is not limited to this. For example, although the container is illustrated as the work table 6, it may be a flat work table used for maintenance of the airframe. Further, the scissor link mechanism 4 may be composed of a plurality of links in the vertical direction.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used as a scissor link mechanism type aerial work vehicle in which a work table can be raised and lowered.

It is a side view showing an example of an aerial work vehicle of the present invention. It is AA sectional drawing which abbreviate | omits and shows some aerial work vehicles in FIG. It is explanatory drawing which shows the bottom face side of the work bench | platform in the aerial work vehicle of this invention. It is explanatory drawing of the arrangement | positioning relationship of the hydraulic cylinder, the shaft, and the roller by the side of a work-table bottom in the conventional aerial work vehicle, (a) shows the standby position of a work-table, (b) shows the work position of a work-table.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Height work vehicle 2 Driver's cab 3 Chassis 31 Chassis frame 4 Scissor link mechanism 41 Inner link 42 Outer link 43 Link shaft 44 Hydraulic lift cylinders 51 and 52 Shaft 6 Work table 61 Work table frame 62 Roller 63 Guide rail 7 Hydraulic cylinder 71 Cylinder tube 72 Piston rod 81 Bearing trunnion 82 Split bearing 83 Bolt

Claims (2)

In an aerial work vehicle where a scissor link mechanism is arranged between the chassis and the work table, and the work table is raised and lowered between the chassis and the high place by the scissor link mechanism,
A roller provided rotatably at the upper end of the scissor link mechanism is disposed on the bottom surface of the work table so as to roll in a guide rail extending in the front-rear direction. The bottom surface of the work table is parallel to the guide rail. A hydraulic cylinder is provided,
The hydraulic cylinder has a piston rod connected to a work table and a cylinder tube connected to a roller shaft,
The shafts of the left and right rollers are respectively connected to both sides of the rod side end of the cylinder tube of the hydraulic cylinder,
Aerial characterized by advancing to the working position the platform from the standby position in a high place by the expansion operation of the hydraulic cylinder. The aerial work vehicle according to claim 1,
The inner end portions of the shafts of the left and right rollers are detachably attached to the bearing portions formed on the left and right side portions of the bearing trunnion provided on the rod side end portion of the cylinder tube of the hydraulic cylinder. An aerial work vehicle characterized by being fitted and supported by a split bearing .

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