JPH08113915A - One point turning wheel of concrete cutter - Google Patents

Abstract

PURPOSE: To make it possible to eliminate such a situation that one point turning wheel is not turnable just because only a driven wheel comes to a ground in a two wheel-concrete cutter which comprises a drive wheel and a following wheel and prevent the one point turning wheel from running up when passing on a projected surface and further prevent harmful effects, produced by housing failure of the one point turning wheel after the turning operation is over in a rising/driving lever of the one point turning wheel. CONSTITUTION: A one point turning wheel 1 of single wheel driven by a one point turning wheel drive motor 2 is so arranged as to overlap with a side view front wheel 6. When the operator loosens his hold of the one point turning operation lever L after turning operation, it returns to the neutral stage and then resets in the stage which retracts the one point turning wheel 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-point turning of a concrete cutter for cutting a pavement surface to enable excavation for construction work such as piping when constructing a road paved with concrete or asphalt. Regarding the structure of the ring.

[0002]

2. Description of the Related Art A conventional one-point swivel wheel of a concrete cutter is as disclosed in Japanese Patent Laid-Open No. 6-116910, in which the one-point swivel wheel has a pivot point near a rear wheel in a side view. One of each of the left and right arms is laterally supported at the tip of each arm, and is arranged so as to be in contact with the ground at a rear side slightly away from the front wheel in a side view. Also,
Of the pair of left and right single-point turning wheels, one is the driving wheel and the other is the driven wheel.

[0003]

In the structure of the conventional one-point slewing wheel, if the vehicle body passes over a convex surface, the one-point slewing wheel or the one-point slewing wheel is separated from the front wheel axle when viewed from the side. The arm that supports the vehicle rides on the apex of the convex surface, hinders steering, and causes damage. Further, when the driving wheel of the pair of left and right single-point turning wheels is separated from the ground and only the driven wheel is in contact with the ground, the driving wheel may idle and the single-point turning may be stopped.

Further, in order to perform a one-point turning operation of the concrete cutter, three steps of ascending, descending, and stopping for raising and lowering the one-point turning wheel are provided in one turning direction of the lever, and one-point turning wheel is provided in another turning direction. It is also known to provide a lever provided with three steps of a left turning drive in driving, a right turning drive, and a drive neutral position at the same position as the stop step in raising and lowering the one-point turning wheel. Requires an operation to return the lever to the neutral stage (stop stage) when the vehicle turns to the target direction, and the operation may be delayed, causing the aircraft to deviate from the target direction. Also, unless you turn to the target position and return to the neutral (stop) stage and then switch the lever to the up stage and store the one-point turning wheel, the front wheel will not be touched down and you will forget this operation and go straight. If you do, the aircraft will shake because it has no straightness. Therefore, it is desirable that the one-point turning wheel always be in the stored state after turning.

[0005]

The present invention uses the following means in order to solve the above problems. That is, in the concrete cutter, a single-point swivel wheel including one drive-controllable wheel is provided near the front wheel shaft in side view.

[0006] Further, the lever is provided with three stages of ascending / descending / stopping for raising / lowering the one-point turning wheel in one turning direction, and in the other turning direction, left turning drive and right turning drive in the one-point turning wheel drive. , And a concrete cutter having a lever provided with three drive-neutral stages at the same position as the stop stage for lifting and lowering the one-point turning wheel, when the hand is loosened after the left / right turning operation of the lever, the lever naturally returns to the stop stage. , And configured to return to the ascending stage.

[0007]

By configuring the one-point swivel wheel of the concrete cutter by one drive wheel, the conventional situation in which only the driven wheel touches the ground and the drive wheel idles can be eliminated. Also,
Since it is provided in the vicinity of the front wheel shaft in a side view, the single-point turning wheel does not project downward from the lower end portion of the front wheel even when passing over the convex surface in the housed state, and the riding does not occur.

Further, after the lever is turned, the user can immediately return to the stop stage by simply loosening his / her hand and the drive of the one-point turning wheel is stopped. After the stop stage is returned, the lever naturally returns to the ascending stage to make a turn. After the operation, the one-point swivel wheel is always stored and straightness can be obtained.

[0009]

The problems and configurations to be solved by the present invention are as described above, and the embodiments of the present invention shown in the accompanying drawings will be described below. 1 is an overall side view of the concrete cutter, FIG. 2 is an overall plan view of the same, and FIG. 3 is an overall front view of the same.
Is a partial plan view near the one-point turning operation lever L, FIG. 5 is an internal side view of the main body cover of the concrete cutter showing the one-point turning operation lever mechanism and the one-point turning wheel storage / projection control mechanism, and FIG. 6 is a hydraulic pressure of the concrete cutter. It is a control circuit.

The overall construction of the concrete cutter will be described with reference to FIGS. 1 to 3. The engine etc. are mounted on the main frame 8 and covered by the main body cover 9,
Step 12 is extended from the rear end of the main frame 8,
A seat 13 is supported, an operation panel 10 is provided at a rear portion of the body cover 9, a steering handle 11 is provided in a protruding manner, and a traveling speed change lever, a lift arm elevating lever, and a one-point turning lever are provided in the vicinity thereof. L is provided.

A rear end of a lift arm 14 is pivotally supported on one side surface of the main frame 8, and a cutter driving motor 15 which is a hydraulic motor is provided at a front end of the lift arm 14.
Is provided, and its motor shaft is inserted into a cutter shaft transmission described later, and the cutter disc 16 is installed on the output shaft of the cutter shaft transmission so as to be installed along the lift arm 14.
Is fixed, and the upper half of the cutter disk 16 is covered with a cutter frame 17 attached to the lift arm 14. Further, in front of the front end of the lift arm 14,
A marker 18 that is a straight ahead target is extended so as to be able to touch the ground.

Below the main frame 8, driving wheels are suspended in the rear part, and left and right rear wheels 7, 7, which can be turned by the steering handle 11, are suspended, and non-driving wheels in the front part. , The left and right front wheels 6.6 fixed in the straight direction
Is suspended. Then, a lateral rotation fulcrum shaft 4 is provided slightly forward of the rear wheels 7, 7, and the rear end of the one-point swivel wheel arm 3 is pivotally supported on the rotation fulcrum shaft 4 so as to be rotatable forward. Extending, the one-point slewing wheel drive motor 2, which is a hydraulic motor capable of forward and reverse rotation, is fixedly installed at the front of the one-point slewing wheel arm 3.
A motor shaft 2a of the one-point swivel wheel driving motor 2 is provided so as to project forward and serves as an axle of the one-point swivel wheel 1, and the one-point swivel wheel 1 is disposed sideways so as to overlap with the front wheels 6 and 6 in a side view. are doing.

The single-point slewing wheel drive motor 2 fixed to the single-point slewing wheel arm 3 has a single-point slewing wheel lifting cylinder 5 which is a hydraulic cylinder pivotally supported by the main frame 8.
As shown in Fig. 5, the tip of the cylinder rod is pivotally connected.
By expanding and contracting the cylinder rod, the one-point slewing wheel arm 3 can be pivoted up and down to bring the one-point slewing wheel 1 upward to be in a stored state, or can be lowered to a protruding state for grounding. Rod extension / contraction drive is performed by vertically rotating the one-point turning wheel operation lever L.

The one-point turning operation lever L will be described in detail. As shown in FIG. 4, this lever is a cross-rotating lever, and is used to perform the forward / backward rotation operation to move the one-point swivel wheel 1 back and forth, and the left / right rotation operation to perform the swivel operation. In the withdrawal operation, when the forward tilting is set to the projecting position A, the single-point turning wheel 1 is set to the projecting state, and when tilting backward to the storage position B,
When it is set to the central neutral position N, the single-point turning wheel 1 stops moving up and down at that position.
When the vehicle is tilted leftward from the neutral position N to the left turning position C, the one-point turning wheel 1 rotates leftward to make a left turn, and when tilted to the right to the right turning position D, the one-point turning wheel D is turned. 1 turns to the right and makes a right turn.

The one-point turning operation by the one-point turning operation lever L will be described. First, when the one-point swivel wheel 1 is in the stored state and the one-point swivel operation lever L in the initial storage position B is tilted forward to the projecting position A, the cylinder rod of the one-point swivel wheel lifting cylinder 5 extends. The single-point turning wheel 1 is lowered to contact the ground, and the front wheels 6 and 6 are floated above the ground. Next, when the one-point turning lever L is returned to the neutral position N, the driving of the one-point turning wheel lifting cylinder 5 is stopped,
The one-point turning wheel 1 is fixed in a protruding state, and in this state, the one-point turning operation lever L is moved to the left turning position C or the right turning position D.
And drive the one-point turning wheel drive motor 2 to
When the one-point turning wheel 1 is rotated in either direction, the machine body rotates about the center of the axle of the rear wheels 7 and 7 with the front end of the machine body rotating sideways with the lateral driving of the one-point turning wheel 1 to make a one-point turning. Done.

When the vehicle is turned in a target direction and the force of gripping the one-point turning control lever L is released or when the hand is released, the one-point turning control lever L naturally returns to the neutral position N and at the same time The slewing wheel drive motor 2 immediately stops driving, and the one-point slewing wheel 1 immediately stops driving. Therefore, the aircraft immediately stops in the turning direction. Further, the one-point turning operation lever L naturally returns from the neutral position N to the storage position B, the cylinder rod of the one-point turning wheel lifting cylinder 2 contracts, and the one-point turning wheel 1 is raised to be stored, and the front wheels 6 and 6 are stored. The aircraft is grounded, and the aircraft is fixed in the direction in which turning has stopped, ensuring straightness in that direction. That is, the one-point turning wheel 1 is forcibly stored after the turning operation is performed.

Next, focusing on the drive system for the one-point turning wheel 1, the hydraulic drive system for the concrete cutter will be described with reference to FIGS. 5 and 6. First, the power of the engine E is the body cover 9
It is transmitted to a continuously variable transmission 23 for traveling, a hydraulic pump P1 for turning / lifting, and a hydraulic pump P2 for driving a cutter, which are internally provided. The motor output shaft of the traveling continuously variable transmission 23 is inserted into the traveling transmission 24 to control the drive of the rear wheels 7 and 7. The cutter driving hydraulic pump P2 is the cutter driving motor. Pressure oil is supplied to 15, and is transmitted to the cutter shaft transmission 25 at the subsequent stage to rotationally drive the cutter disk 16.

The turning / lifting hydraulic pump P1
Supplies pressure oil into the cutter / single-point slewing wheel lifting valve device 19, and further supplies pressure oil into the subsequent one-point slewing wheel drive valve device 20. In the cutter / single-point turning wheel raising / lowering valve device 19, a lift arm raising / lowering valve V1 for switching the lift arm raising / lowering cylinder 21 to a rising / lowering / stopping position is internally provided so as to be switchable by a lever. The valve V2 for raising and lowering the one-point turning wheel is disposed in the subsequent stage, but for safety, the one-point turning is performed only when the valve V1 for raising and lowering the lift arm is at the stop position, that is, when the cutter disk 16 is stopped moving up and down. Pressure oil is supplied to the wheel lifting valve V2.

The one-point slewing wheel lifting valve V2 is switched by the forward / backward rotation operation of the one-point slewing wheel operating lever L, and extends and retracts the cylinder rod of the one-point slewing wheel lifting cylinder 5. In addition, the initial position is the cylinder rod contraction drive state, the one-point swivel wheel operating lever L also has the storage position B as the initial position, and the spring is biased to return from the neutral position N to the storage position B. It has been done.

A valve V3 for driving a one-point turning wheel is provided in the valve device 20 for driving a one-point turning wheel in the subsequent stage.
When the one-point slewing wheel lift valve V2 stores or stops the one-point slewing wheel 1, pressure oil is supplied to the one-point slewing wheel drive valve V3. An oil passage from the one-point slewing wheel lifting valve V2 to the one-point slewing wheel drive valve V3 branches toward the cutter driving hydraulic pump P2 via the charge relief valve 22, and an extra Hydraulic pump P2 for cutter drive that requires horsepower with pressure oil
I am trying to replenish the charge pressure to.

The one-point turning wheel drive valve V3 is switched by a left-right turning operation from the neutral position N of the one-point turning control lever L, and the one-point turning wheel drive motor 2 is driven to the left turning state.・ Switch to the right turn drive state / drive stop state. The one-point turning wheel drive valve V3 and the one-point turning operation lever L are spring-biased toward the neutral position N, and naturally return to the neutral position N when the lever hands are loosened. Further, after returning to the neutral position N by the above configuration, since it is urged toward the storage position B, it is returned to the storage position B.

[0022]

The present invention has the following effects because the muddy water discharge pump in the concrete cutter is constructed as described above. First, as described in claim 1, since the one-point turning wheel is composed of one wheel which can be drive-controlled, a situation where turning is not possible due to idling does not occur, and the fact that it is near the front wheel shaft in side view results in a convex surface. Even when passing, the one-point turning wheel and the arm that supports it do not climb up and do not stop running or get damaged.

Further, in a concrete cutter having a lever for raising and lowering and driving a one-point turning wheel as in claim 2, when the machine turns to the left and right and the machine turns to a target direction, it is only necessary to loosen the hand from the lever. Since it returns to the neutral stage, the drive of the one-point swivel wheel stops immediately, the aircraft stops in the target direction, and the lever returns to the ascending stage from the neutral stage (stop stage), so the one-point swivel wheel is stored. There is no longer a situation in which you forget to forget to move the aircraft straight and shift the direction of the aircraft.

[Brief description of drawings]

FIG. 1 is an overall side view of a concrete cutter.

FIG. 2 is an overall plan view of the same.

FIG. 3 is likewise an overall front view.

FIG. 4 is a partial plan view of the vicinity of a one-point turning operation lever L.

[Fig. 5] One-point swivel lever mechanism and one-point swivel wheel storage
It is an internal side view of the main body cover in the concrete cutter which shows a protrusion control mechanism.

FIG. 6 is a hydraulic control circuit of a concrete cutter.

[Explanation of symbols]

 L Single-point turning control lever V2 Single-point turning wheel lifting valve V3 Single-point turning wheel drive valve 1 Single-point turning wheel 2 Single-point turning wheel drive motor 3 Single-point turning wheel support arm 4 Rotation fulcrum shaft 5 Single-point turning wheel lifting cylinder 6 Front wheel 7 rear wheels

Claims (2)

[Claims] 1. A concrete cutter single-point swivel wheel comprising a drive-controllable single-point swivel wheel provided near a front wheel shaft in a side view. 2. A lever is provided with three stages of raising, lowering, and stopping when raising and lowering a one-point turning wheel in one turning direction, and in another turning direction, left turning drive and right turning drive in one-point turning wheel drive. , And a concrete cutter having a lever provided with three drive-neutral stages at the same position as the stop stage for lifting and lowering the one-point turning wheel, when the hand is loosened after the left / right turning operation of the lever, the lever naturally returns to the stop stage. , A single-point slewing wheel for a concrete cutter that returns to the ascending stage.