JPH0720156Y2 - Swing lifting device for work equipment - Google Patents

Description

[Detailed Description of Device] a. DISCLOSURE OF THE INVENTION Object of Invention (Field of Industrial Use) The present invention relates to a work vehicle having a working device at the tip of a boom, and more particularly to a device for swinging and vertically moving the working device with respect to the tip of the boom.

(Prior Art) An aerial work vehicle equipped with a boom that can freely move up and down and a bucket (working device) at the tip of the boom is used for installation work of distribution electrical equipment materials on electric poles and assembly work of buildings. To be
Furthermore, in order to improve work efficiency, many aerial work vehicles are also used, which are configured to swing the bucket in the left-right direction with respect to the boom tip and move up and down.

As a mechanism for swinging and moving the bucket up and down as described above, there is, for example, one proposed in Japanese Utility Model Laid-Open No. 63-59197. In this device, an elevating mechanism including a cylinder and a wire is attached to the side portion of the bucket, and the above-mentioned device is attached to the side of the swinging device (front of the boom) that is swingably attached to the tip of the boom about a vertical swinging shaft. The lifting mechanism is connected. For this reason, the bucket and the lifting device slide up and down at the connecting portion with the swinging device to move up and down, while swinging integrally.

(Problems to be Solved by the Invention) However, in the swinging device and the lifting mechanism having the above-described configuration, the lifting device and the bucket are arranged at positions horizontally separated from the swing shaft of the swinging device, and Since the distance to the bucket becomes long because the lifting device is attached between the bucket and the swinging device, a large moment (a moment due to the weight of the lifting device and the bucket) acts on the swinging device. For this reason, the swinging device is required to have a high strength, the structure becomes complicated, and there is a problem in that the swinging of the bucket and the stability at the time of raising and lowering operation are lacking. Also,
There is also a problem that the mechanism becomes complicated, for example, the connecting portion is configured to be slidable.

In view of the above problems, in the present invention, a lifting mechanism is arranged on the swing shaft of the swing device, which is advantageous in terms of strength and improves work stability of the work device on the boom. It is an object of the present invention to provide a swinging lifting device for a device.

B. In order to achieve the above object, in the present invention, one end of a cylinder is vertically attached to the tip of the boom, and a sheave is attached to the other end of the cylinder. A post member is attached to the outer periphery of the cylinder so as to be vertically movable along the cylinder, and a working device is attached to the post member so as to swing freely around the cylinder. , One end of the boom to the tip side,
The other end is fixed to the post member side.

(Operation) In such a swinging lifting device, the swinging operation of the working device is performed around the post member as an axis, while the post member side of the wire wound around the sheave that moves up and down according to the expansion and contraction operation of the cylinder. By moving the fixed end up and down, the post member is moved up and down with respect to the boom tip, and the working device is moved up and down.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

First, FIG. 3 shows an aerial work vehicle equipped with a swinging lifting device according to the present invention. Outriggers 2 are arranged at four positions on the front, rear, left and right of a vehicle body 1 of this aerial work vehicle. When performing work, the outriggers 2 are extended to the side of the vehicle body 1 and are extended downward to support the vehicle body 1. Also,
A swivel base 3 is mounted on the vehicle body 1. The swivel base 3 can swivel with respect to the vehicle body 1. Also,
A base end portion of a telescopic boom 4 formed by inserting a tip boom 4b into the base end boom 4a is pivotally attached to the swivel base 3. The boom 4 can be lifted and lowered by expanding and contracting a hoisting cylinder 5 provided between the swivel 3 and the base boom 4a.
Further, the tip boom 4b can be expanded and contracted by an expansion and contraction operation of an expansion and contraction cylinder (not shown) mounted inside the boom 4. The swinging lifting device 6 is attached to the tip of the tip boom 4b, and a bucket (working device) 7 is mounted in front of the swinging lifting device 6 via an arm member 8.

Next, the swinging lifting device 6 will be described with reference to FIG.

The tip of the cylinder rod 11a of the lifting cylinder 11 is pivotally attached to the tip of the tip boom 4b. An upper end of the leveling arm 4c is fixed to the tip of the cylinder rod 11a, and a leveling cylinder 4d is pivotally mounted between the lower end of the cylinder rod 11a and the tip boom 4b. These link mechanisms prevent the boom 4 from rising and falling. Instead, the lifting cylinder 11 is maintained vertically.

The upper part of the cylinder tube 11b of the lifting cylinder 11 has a first
A slider 12 is mounted around. The outer diameter of the sliding surface 12a of the first slider 12 is substantially equal to the inner diameter of the post member 14 described later. Further, a sheave 13 is rotatably attached to the upper end of the cylinder tube 11b. The cylinder tube 11b is configured so as not to rotate about the axis with respect to the piston rod 11a.

A hydraulic circuit 20 for operating the lifting cylinder 11 having such a structure is shown in FIG.

The suction port of the hydraulic pump P is connected to the oil tank T, and the discharge port thereof is connected to the main oil passage 21 connected to the bottom side oil chamber 11c of the lifting cylinder 11. On the main oil passage 21, from the upstream side, a rising valve 22, a natural lowering prevention check valve 23, and a fuse valve 24 are arranged. The ascending valve 22 is a two-position switching valve, and is switched to a position where the main oil passage 21 is opened or a position where hydraulic oil is drained to the oil tank T by energization and de-excitation of the solenoid 22a. Check valve 23 for preventing natural fall
Opens the main oil passage 21 from the upstream side to the downstream side, while closing it in the opposite direction. The fuse valve 24 is a two-position switching valve, and when the oil pressure on the upstream side is higher than the oil pressure on the downstream side, the fuse valve 24 is located at a position where the main oil passage 21 is opened, and the downstream side, that is, the bottom side oil chamber 11c. When the hydraulic pressure on the side is higher than that on the upstream side, it switches to the position on the closing side.

A drain oil passage 25, which is connected to the oil tank T, branches off in the main oil passage 21 downstream of the check valve 23 for preventing natural fall. A descent valve 26 is arranged on the drain oil passage 25. The descending valve 26 is a two-position switching valve, and is switched to a position where the drain oil passage 25 is closed or a position where the drain oil passage 25 is opened by energization and de-excitation of the solenoid 26a. A signal line is connected to the solenoids 22a and 26a from an operation switch (not shown) mounted on the bucket 8.

Lifting cylinder operated by the hydraulic circuit having such a configuration
A post member 14 is attached to the outer periphery of 11. The post member 14 is a cylindrical member having a length that covers from above the sheave 13 to the lower end of the cylinder tube 11b. A second slider 15 is attached to the inner circumference of the lower end of the post member 14. The inner diameter of the sliding surface 15a of the second slider 15 is
It is almost the same as the outer diameter of the cylinder tube 11b. The post member 14 is guided by the sliding of the second slider 15 with the outer surface of the cylinder tube 11b and the sliding of the first slider 12 with the inner surface of the post member 14, and the tip of the tip boom 4b, that is, the boom 4 is guided. It moves vertically (moves up and down) with respect to the tip of. In addition, the sheave 13 has a wire 16
Is hung around. One end of the wire 16 is at the upper end portion (boom tip side) of the leveling arm 4c, and the other end is a fixed position near the second slider 15 in the post member 14.
It is fixed to 14a. The post member 14 is configured so as not to rotate about the axis with respect to the lifting cylinder 11 (that is, with respect to the tip of the boom 4).

A base end portion of an arm member 8 composed of upper and lower plate-shaped members 8a is rotatably attached to the post member 14 at an intermediate portion and a lower portion of the outer peripheral surface of the post member 14, respectively.
The bucket 7 is attached to the tip of the arm member 8. In addition, a worm wheel 17 is mounted on the outer periphery of the post member 14 at approximately the middle of the mounting position of the two plate-shaped members 8a (see FIG. 2). further,
A swing motor 18 is mounted in the arm member 8. The output shaft of this swing motor 18 has a worm pinion 19
Is fixed, and the worm wheel 17 meshes with the worm pinion 19.

Next, the operation of the head swinging / lowering device 6 will be described.

First, when swinging the bucket 7 with respect to the tip of the boom 4, the swing motor 18 is operated. As a result, the worm pinion 19 rotates and tries to drive the worm wheel 17 that meshes with the worm pinion 19, but the worm wheel 17 is fixed to the post member 14, and the post member 14 pivots with respect to the tip of the boom 4 as described above. Therefore, the swing motor 18 and the side of the arm member 8 for fixing the swing motor 18 are swung by the reaction force from the worm wheel 17, and the swing motion of the bucket 7 is performed.

When the bucket 7 is raised, the operation switch on the bucket 7 is turned on to excite the solenoid 22a, and the check valve 23 and the fuse valve 23 for preventing the hydraulic oil from naturally falling are provided.
The oil is introduced into the bottom side oil chamber 11c of the elevating cylinder 11 via 24, and the elevating cylinder 11 is extended. For example, when the elevating cylinder 11 is extended from the state shown by the solid line in FIG. 1 (fully contracted state), as the sheave 13 rises due to this extension, the fixed end of the wire 16 on the side of the post member 14 (hereinafter, movable) is moved. The position (referred to as the edge) rises. The lifting cylinder 11
The moving amount of the movable end is twice as large as the extending amount of. Therefore, when the lifting cylinder 11 is fully extended, the chain line is shown in FIG.
As shown at 14 ', the post member 14 includes a lifting cylinder 11
The amount of stroke is almost doubled. When the lift cylinder 11 reaches the fully extended state, the hydraulic pressure in the bottom side oil chamber 11c rises, so that the fuse valve 24 is switched to the closed position, and further inflow of hydraulic oil is blocked.

When lowering the bucket 7, the solenoid 22a is de-energized to position the raising valve 22 on the drain side, and the solenoid 26a is excited to position the lowering valve 26 on the drain side. By positioning the ascending valve 22 at the drain side position, the hydraulic oil discharged from the pump P is drained to the oil tank T as it is, and at the same time, the descending valve 26 is located at the drain side position. The hydraulic oil in the side oil chamber 11c is also the oil tank T.
Be drained to. In this way, the lifting cylinder 11 is shortened and the bucket 7 is lowered.

As described above, the bucket 7 swings and moves up and down with respect to the tip of the boom 4.
The moment acting on the post member 14 and the post member 14 is generated only by the weight of the bucket 7 and the operator riding the bucket 7, so that stable swinging and vertical movement can be secured.

In this example, the piston rod 11a is pivotally attached to the tip of the boom 4, but conversely, the lower end of the cylinder tube 11b is pivotally attached to the tip of the boom 4.
The sheave 13 may be attached to the upper end of a.

C. Effect of the Invention As described above, by using the swing raising / lowering device of the working device of the present invention, the raising / lowering mechanism including the cylinder and the wire is provided in the post member which is the central axis of the swinging operation to raise and lower the post member. Since the working device is moved up and down by means of the above, the above-described swinging lifting device only needs to support the moment due to the weight of the working device, and is advantageous in strength and has a simple structure. Further, the working device can perform a swinging operation and a lifting operation with high stability.

[Brief description of drawings]

FIG. 1 is a side view of a swing-up / down device of a working apparatus according to the present invention, FIG. 2 is a top view of the swing-up / down device, and FIG. FIG. 4 is a perspective view of the vehicle, and FIG. 4 is a hydraulic circuit diagram for operating the lifting cylinder in the swinging lifting device. 4 ... Boom, 7 ... Bucket 11 ... Lifting cylinder, 13 ... Sheave 14 ... Post member, 16 ... Wire 17 ... Worm wheel 18 ... Swing motor 19 ... Worm pinion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Shimada, 1015 1152 Yamashita, Ryoke, Ageo, Saitama, Saitama Prefecture, inside Ageo Plant, Aichi Vehicle Co., Ltd. (72) Yasuhiro Katayama 1152 Yamashita, Ryoke, Ageo, Saitama 10 Aichi Vehicle Co., Ltd. Ageo Plant (72) Creator Minoru Ota 414-1 Higashimine Sugawa, Shinji-mura, Tone-gun, Gunma Aichi Vehicle Co., Ltd. Ageo Plant

Claims (1)

[Scope of utility model registration request] 1. A cylinder having one end vertically attached to the tip of a boom, a sheave attached to the other end of the cylinder, and an outer periphery of the cylinder movably in the vertical direction along the cylinder. A post member, a wire wound around the sheave and having one end fixed to the tip end side of the boom and the other end fixed to the post member side, and the post member being swingable about the post member. A swinging / lifting device for a working device, comprising: a working device attached to the working device.