JPH08295498A - Working vehicle - Google Patents

Abstract

PURPOSE: To eliminate a need for a space for an oil feed, to decrease the size of a vertical stay, and to reduce weight by a method wherein a feed discharge port is arranged on one end side of a first expansion cylinder coupled to the base end part of a basemost end stay, and a feed discharge port to a second expansion cylinder is arranged on the other end side coupled to the tip part of a forwardmost tip stay. CONSTITUTION: A feed discharge port to a first expansion cylinder 20 is formed in the end part of a tip rod 24 and feed and discharge is effected from the base end part side of a basemost end stay 40 through a counter balance valve 28 connected directly to the feed and discharge port. A feed and discharge port to a second expansion cylinder 39 is arranged on the opposite rod side of a cylinder 45 and feed and discharge are effected through the tip part side of a forwardmost tip stay 44 through a counter balance valve 48 connected directly to the feed and discharge. Thus, the feed of oil to the first and second expansion cylinders 20 and 39 is effected from the outside without flowing through a vertical stay 38. Thus, the size of the vertical stay 38 is decreased by an amount equivalent to the above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swivel base mounted on a vehicle so as to swivel and swivel driven by a swivel drive device.
An extendable boom that is mounted on a swivel so that it can be raised and lowered by an upright drive device and is extended and retracted by an extendable drive device, and its proper position at the tip of the boom maintains a vertical posture regardless of the boom's up and down motion. The present invention relates to a work vehicle including a multi-stage telescopic vertical column that is mounted in this manner and is telescopically driven by a column telescopic drive device, and a work platform attached to the lower end of the vertical column.

2. Description of the Related Art Conventionally, as shown in FIG. 5, a work vehicle of this type is conventionally mounted on a vehicle 1 so as to be swingable, and is swung up and down on a swivel base 3 which is swiveled by a swivel drive device 2. And a retractable boom 6 which is driven to move up and down by an up-and-down drive device 4 and is driven to extend and retract by an extend-and-retract drive device 5, so that the proper position of the boom 6 is maintained at a proper position regardless of the up-and-down motion of the boom 6. And a workbench 9 attached to the lower end portion of the vertical support column 8.

As shown in FIG. 6, the vertical columns 8 are
A stanchion having a quadrangular cross-section, which is the most proximal stanchion 10, a first intermediate stanchion 11 fitted in the most proximal stanchion 10, and a first intermediate stanchion 1.
1. The second intermediate support column 12 fitted internally, the third intermediate support column 13 internally fitted to the second intermediate support column 12, and the most advanced support column 14 internally fitted to the third intermediate support column 13, each from the most proximal support column 10 It is composed of 5 steps of columns that can be expanded and contracted.

A first bracket 15 having one end protruding laterally from the support is provided at the tip of the most proximal end support 10, and a boom tip member 16 is provided at the tip of the boom 6 so as to project below the boom 6.
Is provided, and the overlapping portion of the first bracket 15 and the boom tip member 16 is pivotally supported by the pin 17, and the vertical column 8 is arranged at the tip portion of the boom 6 so as to be capable of undulating. A second bracket 18 is provided at a position where the vertical column 8 pivotally supported by the first bracket 15 faces the tip of the boom 6, and the second bracket 18 is disposed in the boom 6 so that one end is connected to the boom 6 side and the other end is connected to the first side. A leveling cylinder 19 connected to the two brackets 18 is arranged. The leveling cylinder 19 is driven in association with the hoisting motion of the boom 6 so as to maintain the vertical column 8 in a vertical posture regardless of the hoisting motion of the boom.

As shown in FIG. 6, the strut extension / contraction drive device 7 includes a first extension / contraction cylinder 20 having three stages of bamboo shoot type double-acting cylinders and a second extension / contraction unit having three stages of bamboo shoot type double-acting cylinders. It is composed of a cylinder 21. This first
The telescopic cylinder 20 and the second telescopic cylinder 21 are arranged in parallel in the vertical column 8 so as to be vertically aligned in a plan view.

The first telescopic cylinder 20 is composed of a three-stage bamboo shoot type double-acting cylinder in which the intermediate rod 23 is inserted into the cylinder 22 and the tip rod 24 is inserted into the intermediate rod 23 in sequence. (Corresponding to one end described in the claims) is connected to the base end side of the most proximal end column 10, and the tip rod side end of the intermediate rod 23 is connected to the base end side of the first intermediate column 11. The rod side end of the cylinder 22 is connected to the base end side of the second intermediate column 12. The second telescopic cylinder 21 is configured by a three-stage bamboo-cylinder double-acting cylinder in which the intermediate rod 26 is inserted into the cylinder 25 and the tip rod 27 is sequentially inserted into the intermediate rod 26. It is connected to the base end side of the support column 12, the tip rod side end of the intermediate rod 26 is connected to the base end side of the third intermediate support column 13, and the rod side end of the cylinder 25 is connected to the most advanced support column 14.
Is connected to the base end side of.

The feed / discharge port of the first telescopic cylinder 20 is provided at the end of the tip rod 24 (corresponding to one end side in the claims), and the feed / discharge port of the second telescopic cylinder 21 is also the tip rod 27. The counter balance valves 28 and 29 are provided directly at the end portions of the supply / discharge ports. Then, the hydraulic pressure source is supplied to the counter balance valves 28, 29 from the base end side of the most proximal end support column 10, and the counter balance valve 29 is operated by the hydraulic hose 30 from the base end side of the most proximal end support column 10. I have to. The counter balance valve 29 is the tip rod 2
Since it is connected to the second intermediate strut 12 together with 7, the counter balance valve 29 from the base end side of the most proximal end strut 10 when the first intermediate strut 11 and the second intermediate strut 12 are fully extended.
The length of the hydraulic hose 30 is determined so that the hydraulic pressure can be supplied and discharged up to. In addition, the first intermediate support column 11 and the second intermediate support column 1
Since the distance from the base end side of the most proximal end strut 10 to the counterbalance valve 29 changes in conjunction with the expansion and contraction movement of 2, the hydraulic pressure fixed at one end to the base end side of the most proximal end strut 10. The hose 30 is extended to the tip end side, is bent in the middle thereof and is folded back to fix the other end to the counter balance valve 29. In addition, the oil supply from the base end side of the most proximal end support 10 to the counter balance valve 29 is performed by the hydraulic hose 30.
It is also possible to feed oil with a hydraulic hose wound around a hose reel that is always biased in the winding direction, without using a method of bending and folding back the middle of the hose.

[0007]

However, since the supply / discharge port of the second telescopic cylinder 21 is provided at the end portion of the tip rod 27, the counter balance valve 2 is provided in the vertical column 8.
9 and the hydraulic hose 30 had to be provided with a space in which they could be arranged, and the vertical column 8 had to be thick. In particular, it is necessary to provide a protection device in the vertical support 8 so that the hydraulic hose 30 does not come into contact with the first telescopic cylinder 20 and the like, and this requires a large space. However, if the vertical support column 8 is thickened, the weight of the vertical support column 8 increases and the moment related to the boom 6 increases, which is a factor that deteriorates the performance of the work vehicle. Further, it has been a factor of increasing the overall weight of the work vehicle and increasing the stability of the vehicle related to the axle weight and the fall angle.
An object of the present invention is to provide a work vehicle that solves the above problems.

[0008]

In order to achieve the above-mentioned object, a work vehicle of the present invention is mounted on a vehicle so as to be swingable and swung by a swing drive device so as to be capable of undulating. The telescopic boom is driven up and down by the hoisting drive device and is telescopically driven by the telescopic drive device, and the propeller is attached to the tip of the boom so that its proper position is maintained in a vertical posture regardless of the hoisting motion of the boom. In a work vehicle including a multi-stage telescopic vertical column that is telescopically driven by a drive device, and a work platform attached to a lower end portion of the vertical column, the vertical column includes the most proximal column column, one or more intermediate column columns. , Which comprises at least three or more columns that are equipped with the most advanced columns and which are telescopically and sequentially inserted, and the column expansion / contraction drive device has one end connected to the base end of the most proximal end side column. It is composed of at least a first telescopic cylinder that drives the middle strut to extend and retract from the most proximal end strut, and a second telescopic cylinder that connects the other end to the tip of the most advanced strut and extends and drives the most advanced strut from at least the middle strut. A supply / discharge port for supplying / discharging to / from each cylinder is arranged on one end side of the first telescopic cylinder and on the other end side of the second telescopic cylinder, respectively.

[0009]

In the work vehicle of the present invention configured as described above, the supply / discharge port for the first telescopic cylinder is arranged at one end of the first telescopic cylinder connected to the base end of the most proximal end column, and the second telescopic cylinder is installed. Since the supply / discharge port to the cylinder is arranged on the other end side connected to the tip of the most advanced strut, the oil feed to the first telescopic cylinder and oil feed to the second telescopic cylinder pass through the vertical column. You can do it from the outside without doing it. Therefore, a space for arranging the first telescopic cylinder and the second telescopic cylinder is sufficient in the vertical support, and a space for oil supply to the second telescopic cylinder is not particularly required, and therefore, as much as possible. The vertical support can be made thinner accordingly. If the vertical columns are made thin, the weight of the vertical columns is reduced and the moment related to the boom is reduced, so that the performance of the work vehicle can be increased. It also reduces the overall weight of the work vehicle,
It is possible to set a low vehicle stability relating to the axle weight and the fall angle.

[0010]

EXAMPLE A work vehicle of the present invention will be described below with reference to FIGS.
It will be described based on. In addition, reference numerals 1 to 6, 9 and 15 to 2
Since 0, 22 to 24, and 28 are the same as those used in the description of the conventional technique, the same reference numerals are used in the following description. Therefore, in the following description, detailed description of the above reference numerals will be omitted.

In FIG. 1, reference numeral 38 denotes a column having a quadrangular cross section, which is the same as the vertical column 8 described in the prior art except that its thickness is reduced. That is, the vertical column 38 includes the most proximal end column 40, the first intermediate column 41 fitted in the most proximal column 40, the second intermediate column 42 fitted in the first intermediate column 41, and the second intermediate column 42. Third intermediate support column 4 fitted
The third and third intermediate columns 43 are internally fitted with the most up-to-date columns 44, and the proximalmost column 40 is a five-stage column that can be expanded and contracted sequentially. As described in the related art, the first telescopic cylinder is connected to and attached to each of the most proximal end column 40, the first intermediate column 41, and the second intermediate column 42. 39 is
The second telescopic cylinder, which is arranged in the vertical column 38 together with the first telescopic cylinder 20. When arranging the two telescopic cylinders in the vertical support column 38 (the most advanced support column 44), the centers of both cylinders should be positioned on the diagonal line of the most advanced support column 44 as shown in FIG. It is located in. That is, the vertical columns 38 are
The thickness is such that only the space necessary for disposing the telescopic cylinder 20 and the second telescopic cylinder 39 is secured.

The second telescopic cylinder 39 is composed of a three-stage double-acting cylinder in which the intermediate rod 46 is inserted into the cylinder 45 and the tip rod 47 is inserted into the intermediate rod 46 in this order. It is connected to the base end side of the intermediate strut 42, the tip rod side end of the intermediate rod 46 is connected to the base end side of the third intermediate strut 43, and the anti-rod side end of the cylinder 45 (see the claims). (Corresponding to the other end) is connected to the tip end side of the most distal post 44. Second telescopic cylinder 3
9 has a supply / discharge port provided on the side opposite to the rod end of the cylinder 45 (corresponding to the other end side described in the claims), and a counterbalance valve 48 is directly attached to this supply / discharge port. Reference numeral 37 denotes a strut extension / contraction drive device of the present embodiment, which includes a first extension / contraction cylinder 20 and a second extension / contraction cylinder 39.

Next, the oil supply to the second telescopic cylinder 39 will be described below with reference to FIGS. 3 and 4. 40a, 4
Reference numerals 2a and 44a are joints arranged at the tips of the respective columns. 41a is positioned at the tip of the first intermediate support column 41 by the first guide member 50c, which will be described later, when the vertical support column 38 is fully extended, and is located to the side of the most proximal support column 40 when the vertical support column 38 is fully contracted. It is a joint to be positioned. 43a is located at the tip of the third intermediate support column 43 by a second guide member 51c, which will be described later, when the vertical support column 38 is fully extended, and is located to the side of the most proximal support column 40 when the vertical support column 38 is fully contracted. It is a joint to be positioned.
Reference numeral 50 is a first oil feeding device, one end of which is a joint 40.
a first cable bear 50a fixed to a and the other end fixed to a joint 41a; a first oil supply hose 50b arranged along the first cable bear 50a and having both ends connected to the joint 40a and the joint 41a; and a joint 42a. One end is fixed to the other end and the joint 41a is fixed to the other end, and the cross section is formed in a U shape, and the first cable bear 50a is inserted into the U-shaped opening. First guide member 50c for guiding 50a, joint 4
1st oil supply piping 50 which connects between 1a and joint 42a
It is composed of d.

Reference numeral 51 denotes a second oil feeding device, which is a second cable bear 51a having one end fastened to the joint 42a and the other end fastened to the joint 43a, and is arranged along the second cable bear 51a and has both ends joint 42a. And joint 43
Second oil supply hose 51b connected to a, joint 44a
One end is fastened to the other end and the joint 43a is fastened to the other end, and the cross section is formed in a U shape, and the second cable bear 51a is inserted into the U-shaped opening, and the second cable is provided on both sides thereof. It comprises a second guide member 51c for guiding the bear 51a and a second oil feed pipe 51d for connecting the joint 43a and the joint 44a.

The joint 41a is connected to the first oil feeding hose 50.
The inside thereof is configured to connect b with the first oil supply pipe 50d. Similarly, the joint 42a is connected to the first oil feeding pipe 5
0d and the second oil supply hose 51b are connected, and the joint 4
The inside of 3a is configured to connect the second oil supply hose 51b and the second oil supply pipe 51d. As shown in FIG. 4, in order to prevent the first cable bear 50a from being disengaged from the first guide member 50c due to vibration during traveling of the work vehicle when the vertical column 38 is contracted, the first guide member 50c is provided. , The first guide member 50c approaching the joint 42a side
A reinforcing guide portion 50e having both sides raised is provided in the portion of. Similarly, the second guide member 51c is also provided with a reinforcing guide portion 51e.

Reference numeral 40b denotes a joint arranged at the base end portion of the most proximal end column 40, and the joint balance pipe 28 is connected to the counterbalance valve 28. Four
Reference numeral 0c denotes a joint arranged on the most proximal end support column 40 in a position close to the tip of the boom 6, and connects a hydraulic power source from the side of the boom 6 to this joint 40c. Further, the joint 40c connects the joint 40b and the joint 40a with pipes so that a hydraulic pressure source can be supplied to the joint 40b and the joint 40a.

The work vehicle of the present invention thus constructed operates as follows. That is, a supply / discharge port for the first telescopic cylinder 20 is provided at the end of the tip rod 24, and the supply / discharge can be performed from the base end side of the most proximal end support column 40 via the counter balance valve 28 directly connected to this supply / discharge port. I am trying. In addition, a supply / discharge port for the second telescopic cylinder 38 is provided on the side opposite to the rod of the cylinder 45 so that the supply / discharge can be performed from the tip end side of the most-advanced support column 44 via a counter balance valve 48 directly connected to this supply / discharge port. ing. Therefore, the oil can be sent to the first telescopic cylinder 20 and the oil to the second telescopic cylinder 39 from outside without passing through the vertical support column 38. Therefore, a space for arranging the first telescopic cylinder 20 and the second telescopic cylinder 39 is sufficient in the vertical column 38, and a space for oil supply to the second telescopic cylinder 39 is not required. In addition, the vertical column 38 can be made thinner by that amount. When the vertical support column 38 is made thin, the weight of the vertical support column 38 is reduced and the moment related to the boom is reduced, so that the performance of the work vehicle can be increased. In addition, the overall weight of the work vehicle can be reduced, and the stability of the vehicle related to the axle weight and the fall angle can be set low.

In the above embodiment, the oil feeding to the second telescopic cylinder 39 was explained using the first oil feeding device 50 and the second oil feeding device 51 using a cable bear or the like.
The oil transfer from 0a to the joint 44a may be configured by a hydraulic hose and a hose reel that constantly urges the hydraulic hose in the winding direction to wind the hose.

Further, in the above-mentioned embodiment, the description has been given as a technique for extending and retracting the vertical stanchions of five stages by using two three-stage bamboo shoot type double acting cylinders as the telescopic cylinders, but the present invention has three or more stages. It can be applied to vertical columns. For example, when applied to a three-stage vertical column, the first telescopic cylinder and the second telescopic cylinder may be similarly configured by a two-stage double-acting cylinder. When applied to a 4-stage vertical column, either the first telescopic cylinder or the second telescopic cylinder is configured by a double-acting double-acting cylinder, and the other telescopic cylinder is configured by a 3-stage double-acting cylinder. do it. Similarly, if the telescopic cylinder is composed of multi-stage double-acting cylinders, it can be understood without needing to be explained that it can be applied to vertical columns having six or more stages.

[0020]

According to the working vehicle of the present invention constructed and operated as described above, the vertical support can be made as thin as possible, and the weight of the vertical support can be reduced to reduce the moment related to the boom. The performance of the car can be increased. Also,
The overall weight of the work vehicle can be reduced, and the stability of the vehicle related to the axle weight and the fall angle can be set low.

[Brief description of drawings]

FIG. 1 is an explanatory view for explaining the arrangement of a column expansion / contraction drive device according to the present invention.

FIG. 2 is an explanatory view of disposing a telescopic cylinder in a vertical column according to the present invention.

FIG. 3 is an explanatory diagram for explaining an oil feeding device to the second telescopic cylinder of the strut telescopic drive device according to the present invention, and is an explanatory diagram showing a state in which the vertical strut is extended.

FIG. 4 is an explanatory view for explaining an oil feeding device to the second telescopic cylinder of the strut telescopic drive device according to the present invention, and is an explanatory view showing a state in which the vertical prop is contracted.

FIG. 5 is an explanatory diagram illustrating a work vehicle.

FIG. 6 is an explanatory diagram illustrating a conventional strut extension / contraction drive device.

[Explanation of symbols]

 1 vehicle 2 turning drive device 3 turning base 4 hoisting drive device 5 telescopic drive device 5 boom 9 workbench 37 work support telescopic drive device 38 vertical support post 40 most proximal support post 41 first middle support post (intermediate support post) 42 second middle support post ( Intermediate strut) 43 Third intermediate strut (intermediate strut) 44 Cutting edge strut 20 First telescopic cylinder 39 Second telescopic cylinder

Claims (1)

[Claims] 1. A swivel mounted on a vehicle so as to swivel and swivel driven by a swivel drive device, and a telescopic type mounted on a swivel so that it can be hoisted by a hoist drive device and telescopically driven by a telescopic drive device. Boom, a multi-stage telescopic vertical column that is attached to the tip of the boom at a proper position so as to maintain a vertical posture regardless of the boom hoisting motion, and is telescopically driven by a column telescopic drive device, and the lower end of the vertical column In a work vehicle including a workbench attached to a section, the vertical support column includes at least a base end support column, a single or a plurality of intermediate support columns, and a front end support column, and at least three or more stages are telescopically and sequentially inserted. A first expansion / contraction system configured to support the expansion / contraction drive device, wherein one end of the expansion / contraction drive device is connected to the base end of the most proximal end support, and at least the intermediate support is driven to extend from the most proximal end support. And a second telescopic cylinder that connects the other end to the tip of the most advanced strut and extends and retracts the most advanced strut from at least the intermediate strut, and has a first supply / discharge port for supplying / discharging to / from each cylinder. A work vehicle characterized in that the telescopic cylinder is arranged on one end side and the second telescopic cylinder is arranged on the other end side.