JP2609000B2 - Backhoe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for mounting a backhoe device on a side of an operating portion of a swivel base, retreating a boom, an arm and a bucket of the backhoe device toward the swivel base and operating the bucket. The backhoe device is configured to switch to a storage state located on the lateral side of the unit,
The present invention relates to a backhoe provided with a boom merging valve for merging pressure oil supplied from a second hydraulic pump to pressure oil supplied to a boom cylinder by a first hydraulic pump when the boom is driven up.

[0002]

2. Description of the Related Art The above-mentioned backhoe is designed so that the backhoe device can be retracted to the turntable side and turned when there is a relatively narrow space around the fuselage so that the turntable can be turned. is there. That is, a so-called small turn is possible. In this type of backhoe, conventionally, a deceleration target range is set near the rising end stroke end of the boom, and when the boom is located in this deceleration target range,
By automatically switching the boom consolidation valve to the refueling stop position in preference to the control means for the boom control valve and the boom consolidation valve, and by providing buffer means for restricting the boom control valve to the low speed side, When the backhoe device is stored, the boom decelerates at a position short of the stroke end due to the action of the buffering means, and reaches the stroke end at a slow speed so that stop impact does not easily occur, and stops. .

[0003]

In the above-mentioned backhoe, the center of gravity of the whole backhoe apparatus is located on the front side of the swivel base from the boom pivot point of the swivel base as the backhoe apparatus is switched from the working state to the retracted state. From the mounting state of the front center of gravity, to the mounting state of the rear center of gravity where the backhoe apparatus center of gravity is located on the rear side of the swivel base from the swivel table pivot point through the neutral mounting state where the backhoe apparatus's center of gravity is located directly above the swivel table boom pivot point. When the backhoe device is attached to the rear center of gravity, the extension operation force acts on the boom cylinder due to the weight of the backhoe device. When the boom control valve is brought into the set low speed state by the operation of the buffer means, the oil supply side oil passage of the boom control valve becomes in a throttled state, the amount of oil supplied to the boom cylinder per unit time decreases, and the oil discharge side oil is discharged. Due to the increased drainage resistance acting on the boom cylinder due to the road being in a throttled state, conventionally, when the buffering means acts, even if the extension operation force due to the weight of the backhoe device acts on the boom cylinder, Because the oil does not flow out of the boom cylinder and does not flow into the boom cylinder due to the throttling action of the oil supply side and the oil discharge side of the boom control valve, the internal oil pressure in the oil discharge side chamber of the boom cylinder becomes high and oil is supplied. Negative pressure is generated in the side chamber, and pulsating movement of the backhoe device moving toward the stroke end while swinging in the boom elevating direction is likely to occur. It was. SUMMARY OF THE INVENTION An object of the present invention is to enable a slow stop while avoiding pulsating movement of a backhoe device, and to obtain a structure as simple as possible.

[0004]

According to the present invention, there is provided a backhoe according to the first aspect, wherein the boom cylinder moves from a set position between a descending stroke end and an ascending stroke end to the ascending side. Boom position detection means for detecting that the vehicle is located in a range to be decelerated to the stroke end is provided, and a control means for the boom control valve and the boom merge valve permits operation of the boom control valve and the boom merge valve. A buffer means is provided which can be switched between an operating state and an operating state in which the boom control valve is set to a set low speed state prior to the control means, and the boom merge valve is switched to a set amount refueling state. When the boom position detecting means is in a detection state, the control means controls the boom control valve to boom. Are coordinated to automatically switch switched the boom position detecting means and said control means as said working condition when a rising operation state of switching to the rise side. The operation and effect are as follows.

[0005]

When stopping the boom at the stroke end on the rising side, the boom control valve is switched to the throttled state, decelerated and then stopped, whereby the stop impact is alleviated as desired and the deceleration start position and the throttle are stopped. The state is set as the set position or the set low speed state.
Also, even if the boom control valve is switched to the throttled state so that the backhoe moves slowly, the extension operation force caused by the change to the rear center of gravity and the own weight described at the beginning of the backhoe is applied to the boom cylinder. The amount of oil to be supplied so that no negative pressure is generated in the oil supply side chamber of the boom cylinder even if it acts, and that the excessive pressure does not act more than necessary to produce the slow movement of the backhoe device. Is set as the set amount refueling state. Then, in stopping the boom at the rising stroke end, when the rising and swinging boom reaches the set position,
The boom control valve is in the set low-speed state, and the boom merge valve is switched to the set amount refueling state, and the boom merge valve supplies an appropriate amount of oil so that a negative pressure is not generated in the oil supply side chamber of the boom cylinder. The boom cylinder can be controlled to a low speed state by the boom control valve so that the backhoe device moves at a low speed while preventing pulsation of the backhoe device.

[0006]

The pulsation of the backhoe device is prevented by replenishing the oil with the boom confluence valve, so that the impact can be reduced at the time of stoppage, and the operation can be performed in a quiet state with little impact from both sides of the moving condition at the time of the slow speed control immediately before the stoppage. It became so. In addition, the boom confluence valve can be used also as a lubrication valve for cushioning the impact, which is advantageous in terms of structure and economy.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG.
The swivel 2 is attached to the lathe, and the swivel 2 is operated.
Unit 3 and a driving unit 4 and a backhoe device 5
Is attached to form a backhoe with a dozer. Ba
Boom 6 and boom cylinder that constitute hook hoe device 5
C₁To the place located on the side of the operation unit 3 of the turntable 2.
It is attached. Then, as shown in FIG.
Intermediate portion 6 that connects end portion 6a and tip portion 6b
c is the offset cylinder C_FourCan be rocked by
When this swing operation is performed, the boom base
Re-attached to each of the end portion 6a and the boom tip portion 6b.
Link mounting arm 7a or 7b,
Link 7 erected on booms 7a and 7b and boom
The function of the parallel quadruple link mechanism constituted by the intermediate portion 6c is as follows.
The boom tip side part 6b is opposed to the boom base side part 6a.
To move parallel or almost parallel to the side of the turntable.
8 is flat in the horizontal direction of the swivel base with respect to the boom base side portion 6a.
It is configured to move the line. In other words, the offset system
Linda C_FourTo perform the offset operation of the arm 8 due to
As a result, the bucket 9 is positioned at one side end of the traveling body.
It is configured to enable digging, and the arm 8 is turned off.
Fset operation and raising operation of the boom 6 and the arm 8
As a result, as shown in FIGS.
The bucket 8 and the bucket 9 are retired to the swivel
9 is located on the lateral side of the driving unit 3 and the entire backhoe 5
The small swing retracted state where the body enters the swivel
It is configured to be able to store the hookhoe device. back
To enable the operation of the hoe device 5 and the swivel 2,
4. First to third hydraulic pumps A₁, A_Two, A_ThreeProvide
A hydraulic circuit is configured as shown in FIG.
Left swingable in the cross direction of the swivel 2 in the front-rear direction and the horizontal direction
Right pair of operation levers 10a and 10b and offset
Switch S_FourAnd an operation structure as shown in FIG.
Is configured. That is, the arm cylinder C_TwoConnect to
Arm control valve V_Two, Boom cylinder C₁Connected to
Boom consolidation valve V is replaced by hydraulic pilot type proportional control valve
And the second hydraulic pump A_TwoConnected in parallel to
You. Boom cylinder C₁Connected to the boom control valve
V₁, Bucket cylinder C_ThreeConnected to the bucket control valve
Bu V_ThreeIs configured as a hydraulic pilot type proportional control valve.
Both are the first hydraulic pump A₁Are connected in parallel. Offset
Cylinder C_FourOffset valve V connected to_Four, Turning model
Swivel valve V connected to motor M_FiveThe hydraulic pilot type
A third hydraulic pump A configured as a proportional control valve_ThreeParallel to
Connected. The front and rear of the swivel of one operating lever 10a
The operating position in the horizontal direction and the operating position in the horizontal direction of the swivel base.
Sensor S₁And the third sensor S_ThreeBy
And the other operation lever 10
b) The operating position of the swivel base in the front-back direction and the operation of the swivel base in the lateral direction
Working position is the second sensor S made of potentiometer_TwoAnd the fifth
Sensor S_FiveAnd are configured to detect each individually.
You. The sensor S₁, S_Two, S_ThreeAnd S_Five, And said
Offset switch S_FourConsists of a microcomputer
This is linked to the valve control means 11 and
Control means 11 to drive circuit D or D₁Or D_TwoOr D_Threeor
Is D_FourOr D_Five, Through the boom junction valve V, boom system
Your valve V₁, Arm control valve V_Two, Bucket control bar
Luv V_Three, Offset valve V_FourAnd swivel valve V_Fivehusband
Each hydraulic pilot operating part d or d₁Or d_TwoOr d_Three
Or d_FourOr d_FiveIt is linked to And the operation lever
When 10a is manually operated in the front-rear direction of the swivel base, the
Lube control means 11 is a first sensor S₁Based on the detection results
Boom drive circuit D₁Output to the boom control bar.
Luv V₁Switch the boom cylinder C₁Operation
It operates in the direction and speed according to the operating position of the bar 10a.
And stop the operation lever 10a.
When manually operated in the lateral direction, the valve control means 11 is automatically turned on.
Is the third sensor S_ThreeValve drive based on detection results by
Circuit D_ThreeTo the bucket control valve V_ThreeSwitch
Operating the bucket cylinder C_ThreeOf the operation lever 10a
Operate or stop in the direction and speed according to the operating position
It is configured as follows. Move the operating lever 10b forward and backward of the swivel
When manually operated in the direction, the valve control means 11 automatically
2 sensor S_TwoValve drive circuit based on the detection result by
D_TwoTo the arm control valve V_TwoSwitching operation
Arm cylinder C_TwoIs the operating position of the operating lever 10b
To start or stop in the direction and speed
And manually operate the operation lever 10b in the lateral direction of the turntable.
And the valve control means 11 automatically switches the fifth sensor S_FiveBy
Valve drive circuit D based on the detection result_FiveSignal output to
Turning valve V_FiveAnd the turning motor M is operated.
Operates in the direction and speed according to the operating position of the lever 10b
It is configured to stop or stop. Offset switch
Chi S_FourIs switched artificially by the switch lever 10c
When operated, the valve control means 11 automatically offsets
Switch S_FourDrive circuit D based on information from_Four
Signal to the offset valve V_FourSwitch operation,
Offset cylinder C_FourIs the offset switch S_FourCut
It is designed to operate or stop in the direction according to the replacement position.
I have made it. When the valve control means 11 is the first sensor S₁From
Boom control valve V based on the₁Switching operation
At the same time, a signal should be output to the drive circuit D as well.
You can also change the boom merging valve V by
It is configured like this. Turning table 2 of boom 6 as shown in FIG.
Swing angle with respect to boom cylinder C₁For swivel base 2
Boom cylinder C so that it is detected based on the swing angle₁
Boom consisting of a rotary potentiometer attached to the base end of the boom
Corner sensor P₁When the boom position detecting means 12 is linked to
Both the detection means 12 and the valve control means 11
The buffer means 13 associated with the drive circuits D and D₁Signal to
Boom confluence valve V and boom control
Valve V₁To be operated as shown in FIG.
Therefore, when the boom 6 is raised, the first hydraulic pump A₁When
Second hydraulic pump A_TwoHigh speed by pressure oil from both pumps
In order to be able to drive, for that, up to the stroke end
Stops quietly to prevent a stop shock even if it rocks up
I have to do it. That is, as shown in FIG.
Stroke end E of descending side of dome 6₁And rising straw
Kuend E_TwoBetween the set position as the deceleration start position
Stroke end E from position B_TwoBoom swing to
The range is set as the deceleration target range L, and this deceleration target range
When the boom 6 is located at L, this is detected as the boom position.
Means 12 is a boom angle sensor P₁Based on information from
It is configured to be released. Boom position detecting means 12
It is in the non-detection state, and the valve control means 11 is a boom.
Control valve V₁Switch to the ascending side.
At this time, the buffer means 13 is
Based on the information and the information from the valve control means 11.
Drive circuit D and D are switched to the non-active state dynamically.₁To ba
Valve operation based on a signal from the valve control means 11
Output to the valve control means 11
Boom control valve V₁And operation of the boom confluence valve V
It is configured to allow cropping. Boom position detection means
12 is in the detection state, and the valve control means 11 is
Control valve V₁Switch to the ascending side
If present, the buffer means 13 is the boom position detection means 12
On the basis of the information from the
Automatically switch to the operating state, and drive circuits D and D ₁
Boom merges with the signal from valve control means 11
Valve V and boom control valve V₁To the low speed side
By appropriately outputting a signal, the valve control means 11
Boom control valve V₁The setting low speed shown in FIG.
Setting to the state X and the boom merging valve V as shown in FIG.
It is configured to switch to the refueling state Y respectively.
You. That is, when the boom 6 is lifted, the boom 6
Until the set position B is reached, the buffer means 13 is not operated.
The first sensor S of the valve control means 11 in the ready state. ₁Or
Drive circuits D and D based on these information₁Signal output to
Therefore, when the operating lever 10a is at the maximum speed position,
Control valve V₁And opening degree Q of boom merging valve V
Is the maximum opening Qm, and the operation lever 10a is at the highest speed position.
Boom control valve V when in the operating position up to₁as well as
The opening degree Q of the boom merging valve V is set to the operation lever 10a.
The opening Qf becomes proportional to the operation stroke, and boom control
Control valve V₁Is the unit time determined by the opening degree Q of this
The first pump A by the amount of oil supply per interval₁Boom pressure oil from
Cylinder C₁And the boom junction valve V opens
Refueling amount per unit time determined by mouth degree Q
Hydraulic pump A_TwoPressure oil from boom cylinder C₁Join
Supply and boom cylinder C₁Is hydraulic pump A₁And A_Twoof
It operates at high speed by refueling from both. Rise
When the boom 6 reaches the reduction target range L, the buffering means 13
Automatically switches to the operating state, and the boom merging valve V
In this case, the operating position of the operating lever 10a is
Regardless, and boom 6 has reached set position B
From the time point, the opening degree Q shows the set amount refueling state Y.
Opening Qy and the boom control valve V₁Towards
When the operating lever 10a is at the maximum speed position,
From the time when the system 6 reaches the set position B and the operation lever
When 10a is in the operation position up to the highest speed position,
A boom control valve that is determined by the operating position of the lever 10a.
Bu V₁And the set low speed state X appear.
From the time when the opening degree matches, the boom control valve
Bu V₁Opening degree Q along the set low speed state X, and
Boom 6 is on the up stroke end E_TwoOpen closer to
It decreases in a state where the mouth degree Q becomes small. Sand
When the boom 6 enters the deceleration target range L, the boom control valve
Bu V₁Enters the aperture control state, and the boom 6
E _TwoBoom cylinder C to stop slowly₁To
This gives the drainage resistance of the engine. Also, boom 6 rises
As the side swings, the backhoe device 5 moves the center of gravity G
Positioned in front of the turntable from the boom pivot point Z on the turntable 2
From the front center of gravity to be placed, the center of gravity G is shifted to the boom pivot point Z.
Via the switching position F located just above the center of gravity G
Rear center of gravity located on the back side of the swivel table from the boom pivot point Z
It changes to the state, and the extension operation by the weight of the backhoe device 5
Power is boom cylinder C₁Act on the boom cylinder
C₁Boom assembly so that negative pressure hardly
When the flow valve V has the second oil pressure with the oil supply amount determined by the opening Qy
Pump A_TwoOil from boom cylinder C₁To replenish
It is. The boom position detecting means 12 and the buffer means 13 are
It consists of a microcomputer and is based on the flowchart shown in FIG.
It is configured to operate automatically. In addition, shown in FIG.
Service valve V₉Is a valve for the service port
Travel valve V₆Is the traveling motor M₁That control the
And the traveling valve V₇Is the traveling motor M_TwoControl
The dozer valve V₈Is dozer cylinder C₈of
It controls. Hydraulic pump A_FourAre valves V, V
₁Or V_FiveTo supply pilot pressure for the operation of
is there. The arm angle sensor P shown in FIG._TwoIs the arm 8
The swing angle with respect to the boom 6 is detected.
Angle sensor P_ThreeIs the swing angle of the bucket 9 with respect to the arm 8
And the offset sensor P _FourIs bucket
The offset direction to the boom base end portion 6a of the
This is for detecting the amount of lateral movement.

[0008] In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control system.

FIG. 2 is an explanatory diagram of deceleration control.

FIG. 3 is a flowchart of deceleration control.

FIG. 4 is a hydraulic circuit diagram

FIG. 5 is a plan view of a backhoe device.

FIG. 6 is a side view of the entire backhoe.

FIG. 7 is a side view of the entire backhoe.

FIG. 8 is a schematic plan view of the entire backhoe.

[Explanation of symbols]

2 Swivel 3 Operating section 5 Backhoe device 6 Boom 8 Arm 9 Bucket 12 Boom position detecting means 13 Buffering means E ₁ Downward stroke end E ₂ Upward stroke end B Set position L Range of deceleration X Set low speed state Y Set amount refueling State C ₁ Boom cylinder V ₁ Boom control valve V Boom merge valve A ₁ First hydraulic pump A ₂ Second hydraulic pump

Claims (1)

(57) [Claims] 1. A backhoe device (5) is mounted on a turntable (2).
Attach it to the side of the driving section and attach the backhoe
Boom (6), arm (8), and bucket for mounting (5)
(9) retreats to the turntable side, and the bucket (9)
Is in the retracted state located on the side of the driving section (3).
The boom device (5) is configured to switch,
(6) When the first hydraulic pump (A₁) Is a boom
Cylinder (C₁) To the second hydraulic pump (B
_TwoBoom merging valve (V) for supplying the pressurized oil from)
A backhoe provided with the boom cylinder
(6) is the descending stroke end (E₁) And ascending side strike
Row end (E_Two) Above the set position (B)
Ascending side stroke end (E _TwoRange of deceleration up to)
(B) Boom position detecting means for detecting position
(12), and a boom control valve (V₁) And said
By the control means (11) for the steam merge valve (V)
The boom control valve (V₁) And the boom merging valve
A non-operating state permitting operation of the valve (V);
Prior to (11), the boom control valve (V₁)
In a constant low speed state (X), and the boom merging valve
(V) is switched to the set amount refueling state (Y).
And a buffer means (13) that can be switched to a use state.
The buffer means (13) is provided with the boom position detecting means (12).
Is in the detection state, and the control means (11)
Lube (V₁) To the boom raising side in the raising operation state
The boom is automatically switched to the working state at some time.
To the position detection means (12) and the control means (11).
Backhoe linked.