JP2867097B2 - Hydraulic pilot operating device for excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pilot type operating device for an excavating machine capable of forcibly operating a hydraulic actuator even when a hydraulic pump stops due to an engine trouble or the like.

[0002]

2. Description of the Related Art Conventionally, in an excavator, a hydraulic pump and a hydraulic actuator are connected via a control valve, and the control valve controls the operation of the hydraulic actuator. At the base end, a remote control valve is arranged so as to interlock with the front, rear, left and right operations of the operation lever, and the remote control valve and the control valve are connected via a pilot hydraulic path, and the operation of the control valve is controlled by the pilot. There is a hydraulic pilot type operating device configured to be operated by hydraulic pressure.

[0003] Unlike a mechanical operating device in which an operating lever and a control valve are connected by a link mechanism or the like, this does not cause rusting or backlash and facilitates the delicate operation of the excavation work section. Can be done.

[0004]

However, the hydraulic pilot type operating device described above has the following problems to be solved.

That is, in general, when the engine is stopped due to an engine failure or the like during operation of the excavator, the excavator is also stopped because the hydraulic pump is linked with the engine. It will do.

Therefore, when the boom or the like of the excavation work part is located above the ground, it remains stopped at that position.

If the control valve and the operating lever are mechanically connected to each other, the operating lever is operated to activate the control valve, and the hydraulic pressure is released to lower the boom or the like by its own weight. Can be.

However, in the case of the above-mentioned pilot hydraulic excavator, the operating lever and the control valve are connected to each other through a hydraulic pump via a hydraulic pump linked to the engine or a pilot hydraulic pump linked to the engine. Because of the connection, the hydraulic pump is locked by the hydraulic pressure together with the engine stop, and the hydraulic pump does not operate even if the operation lever is moved, so that the excavation work unit cannot be operated to descend.

In this case, the inspection and repair of the excavator must be performed while the boom and the like are positioned at the top, and the boom and the like may fall naturally with time, which is very dangerous.

Further, for example, when it is necessary to replace a pipe or the like at the time of inspection or repair, there is a possibility that the hydraulic oil is ejected at a high pressure due to the hydraulic pressure acting on the pipe. It was extremely dangerous.

An object of the present invention is to provide a hydraulic pilot type operating device for an excavating work machine which can solve the above-mentioned problems.

[0012]

According to the present invention, a hydraulic pump and a hydraulic actuator are connected via a control valve, the operation of the hydraulic actuator is controlled by the control valve, and the control valve and the operating lever are interlocked. While connecting to the remote control valve,
In a hydraulic pilot type operating device for an excavator, which is provided in a pilot hydraulic path and operates a control valve by pilot hydraulic pressure, a pilot pump interlocked with an engine is arranged in the middle of the pilot hydraulic path. A hydraulic supply / discharge device for forcibly generating hydraulic pressure independently of the engine is provided in parallel with the pilot pump, and a supply / discharge device for connecting a downstream side of the hydraulic supply / discharge device to a pilot hydraulic path. A hydraulic pilot type operating device for an excavating work machine, characterized in that a check valve for a supply / discharge device is provided in the middle of a device oil passage.

Further, in the present invention, the hydraulic supply / discharge device comprises an electric pump using a battery as a power source and an operation switch of the electric pump. The hydraulic supply / discharge device can be operated manually. It is also characterized by comprising a drive pump and operating means for the drive pump.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

(First Embodiment) FIG. 1 is a side view of an excavator B equipped with a hydraulic pilot type operating device C according to the present invention, FIG. 2 is an explanatory view showing a control section 5 of the excavator B, FIG. 3 is an explanatory diagram showing a hydraulic circuit of the hydraulic pilot type operating device C.

As shown in FIG. 1, the excavating machine B has a machine frame main body 3 pivotally mounted on a central portion of a crawler type traveling device 1 via a swivel bearing 2 and a central portion of the machine frame main body 3. A cabin 4 is provided, and an excavation work section b is attached to the front side of the machine frame body 3. “e” denotes an engine disposed at the rear of the machine frame body 3.

A control section 5 is provided inside the cabin 4, and a driver's seat 6 is provided in the control section 5, and as shown in FIG.
Arms 19 and 19 are provided above the control boxes 15 and 15, and operation levers 16 and 16 are attached to the left and right of the arm boxes 19 and 19 in front of the arm boxes 19 and 19, respectively.

Reference numerals 17 and 17 denote traveling levers provided in front of the driver's seat 6, reference numeral 20 denotes a meter box protruding forward of the right control box 15, and reference numeral 24 safety lever.

On the other hand, the excavation work part b is provided with a boom bracket mounting fulcrum 7 at the front of the machine frame main body 3, and a boom bracket 8 is mounted on the mounting fulcrum 7 so as to be rotatable left and right. The main boom 9 is mounted so as to be able to move up and down, and a bucket arm 10 and a digging bucket 11 are connected to the tip of the main boom 9 via hydraulic actuators a.

The hydraulic actuator a includes a main boom cylinder 12, a bucket arm cylinder 13, a bucket cylinder 14, and a hydraulic motor m for turning the machine frame body 3, and each hydraulic pump m is linked to an engine e. P is connected to P via a hydraulic valve via a control valve 18 disposed below the cabin 4.

1 and 2, reference numeral 21 denotes a blade having an earth discharging operation and a stabilizer function;
It is an operating cylinder for raising and lowering.

The excavating machine B having the above-mentioned structure is provided with a hydraulic pilot type operating device C, which controls the operation of the hydraulic actuator a by operating the operating levers 16, 16 provided on the control unit 5. , Through a pilot-operated control valve 18.

That is, as shown in FIG. 3, a remote control valve is provided at the base end of the operation lever 16 in four directions of front, rear, left and right.
23 were arranged in conjunction state with the operation of the front and rear left and right respectively the proximal portion, P port 31 inputs the side, in communication with the pilot pump P ₁ side of each remote control valves 23, and the hydraulic oil tank T side A T port 32 is provided which communicates with the T port.

On the other hand, on the output side of each remote control valve 23,
A V port 33 is provided which communicates with the pilot pressure receiving portion 18a of the pilot operated control valve 18. In addition,
Reference numeral 26 denotes a hydraulic hose serving as a flow path for hydraulic oil.

As described above, the remote control valve provided in association with the pilot pump P ₁ and the operation levers 16, 16.
23 and the control valve 18 are connected by a hydraulic hose 26, and these constitute a pilot hydraulic path R.

In the hydraulic circuit, the control valve 18 disposed below the cabin 4 has a hydraulic pump P and each hydraulic actuator a, that is, the main boom 9,
Being interposed between the main boom cylinder 12, the bucket arm cylinder 13, the bucket cylinder 14, and the hydraulic motor m for turning the machine frame body 3 for operating the bucket arm 10, the excavating bucket 11, respectively. become.

When the pilot oil pressure from the remote control valve 23 acts on the pilot pressure receiving portion 18a of the control valve 18, the control valve is actuated by the fluid pressure.
The spool 18 is operated to switch the oil passage and operate the hydraulic actuator a.

The basic configuration of the entire excavator B in this embodiment is as described above, and the gist of the present invention is as follows.
The middle of the pilot hydraulic passage R, together with arranging a pilot pump P ₁ in conjunction with the engine e, lies in the provision of the hydraulic supply and discharge apparatus A forcibly generating hydraulic pressure independently of the engine e . In this embodiment, the hydraulic supply and discharge apparatus A includes an electric pump P ₂ to the battery 30 and power supply, are constructed from the operation switch S of the electric pump P _2.

[0029] That is, as shown in FIG. 3, in the middle of the pilot hydraulic path R, between the pilot pump P ₁ and the remote control valve 23, as the supply and discharge devices for the oil path of the supply and discharge device for a hydraulic hose 27 Connect the proximal end 27a to the end 27b of the hose 27
Connecting the discharge side of the electric pump P ₂ via the supply and discharge device for a check valve 28 to the. Then, the suction side of the electric pump P ₂ is connected to the proximal end 29a of the suction hydraulic hoses 29, its end
The 29 b, are connected to the hydraulic pipe 26a for connecting the hydraulic oil tank T and the pilot pump P _1.

Further, the electric pump P _2, and connects the electric motor M, the electric motor M via the operation switch S, is connected to the battery 30 as a power source.

In this embodiment, the operation switch S
Is provided in the control unit 5 so that the driver can easily operate it in an emergency such as an engine trouble.
Is disposed near the engine e to facilitate normal maintenance. However, the installation location is not particularly limited. In FIG. 3, 25 is a check valve for pilot hydraulic pressure, and 39 is a relief valve.

With the above construction, when the engine e stops for some reason during the excavation work and the excavation work part b stops at a position higher than the ground surface, the operation levers 16 and 16 and the control valve hydraulic pump P interposed between the 18, because the pilot hydraulic pump P ₁ is linked to the engine e, a state in which hydraulic pressure is locked together with the engine stop, excavation work unit or moving the operating lever 16, 16 b cannot be lowered, but if the driver operates the operation switch S, the excavation work part b can be easily lowered to the ground surface.

Therefore, it is possible to quickly avoid a dangerous state in which the excavation work part b is stopped upward, and in a safe state in which the excavation work part b is grounded on the ground surface, the engine e and the like are removed. Can be inspected and repaired.

(Second Embodiment) FIG. 4 shows another embodiment of the hydraulic pilot type operating device C in the excavating machine according to the present invention. Unlike the example, the hydraulic supply / discharge device A is constituted by an accumulation circuit F and an opening / closing cock 38. In the present embodiment, the same reference numerals are used for the same components as those in the previous embodiment.

[0035] That is, as shown in FIG. 4, in the middle of the pilot hydraulic path R, the hydraulic hose 26 for connecting the pilot pump P ₁ and the remote control valve 23, the provided parallel fluid passage 34 as juxtaposed, A relief valve 35 is attached to the parallel oil passage 34, and an accumulator 37 is connected to a branch oil passage 37a branched from the upstream side of the relief valve 35 via a check valve 36.
To form an accumulation circuit F.

[0036] Then, the same accumulator 37, and connects the hydraulic hose 26 for connecting the pilot pump P ₁ and the remote controller valve 23 described above with supply and discharge device for a hydraulic hose 27. An opening / closing cock 38 and a check valve 28 for the supply / discharge device are disposed on the hydraulic hose 27 for the supply / discharge device from the accumulator 37 side.

The hydraulic pilot type operating device C having the above configuration
Is usually off cock 38 is closed, in such a state, the hydraulic oil from the pilot pump P ₁ is the flow to the remote control valve 23 and also flows to the same time accumulation circuit F, through the check valve 36 Flow into the accumulator 37,
By the spring provided in the accumulator 37,
The pressure is stored in the accumulator 37 at a preset pressure.

When the set pressure is reached, the hydraulic oil flowing through the accumulation circuit F has its flow path switched by the relief valve 35 and is returned to the hydraulic oil tank T.

With the above configuration, when the engine e stops for some reason during the excavation work and the excavation work part b stops at a position higher than the ground surface, if the opening / closing cock 38 is opened, the operation in the accumulator 37 is started. Oil remote control valve 23
The control valve 18 can be operated so that the excavation work part b descends by causing the remote control valve 23 to perform a desired operation by the fluid pressure.

(Third Embodiment) Next, as another embodiment,
Drive pump P that can manually operate hydraulic supply / discharge device A
₃ and a hand lever 41 as an operating means of the pump P ₃
Will be described.

In this embodiment, the excavator B shown in FIG. 6 is used, and the first and second excavators B are used.
Differences from the embodiment will be described later in detail. The same reference numerals are used for the same components as those in the first and second embodiments.

The hydraulic pressure supply and discharge device A according to this embodiment, as shown in FIG. 5, in the middle of the pilot hydraulic passage R, between the pilot pump P ₁ and the remote control valve 23, supply and discharge hydraulic path 42 connect the proximal end 42a, it is disposed a driving pump P ₃ to the end 42b of the supply and discharge hydraulic path 42.

[0043] Such driving pump P ₃ is capable of manual operation, the axis of rotation of the pump P ₃ is attached to the hand lever 41 detachably.

[0044] In addition, as a high設個office of the drive pump P ₃ is,
Artificially rotated if the same pump P ₃ by hand lever 41 described above, it is not particularly limited.

In addition to the hand lever 41, a drive pump such as a stepping type, a foot pedal type, etc.
Anything may be used as long as the rotation of the P ₃ manual can be operated.

[0046] Further, between the pilot pump P ₁ and the engine e interlocked with the engine e, is interposed a clutch apparatus or the like, so as to disconnect the drive transmission between the pilot pump P ₁ and the engine e, pilot the pump P ₁ may be shared with the drive pump P ₃ as described above.

Also in this embodiment having the above-described structure, the hydraulic pressure of the pilot hydraulic circuit R can be generated at the time of maintenance and inspection such as when the engine is suddenly stopped, so that the excavating work part b can be lowered. Safety during maintenance and inspection can be achieved.

Furthermore, no electrical wiring is required, and safety can be improved without increasing costs.

As shown in FIG. 6, in this embodiment,
The machine frame body 3 is formed in a substantially circular shape, and a driver's seat 6 is disposed substantially at the center of the machine frame body 3.

The control box 15 has a front specification in which the control box 15 stands upright in front of the driver's seat 6. In the control box 15, a remote control valve 23 is provided.

In FIG. 6, reference numeral 7a denotes a fulcrum for mounting the boom bracket mounting fulcrum 7 and the boom bracket 8, 16a and 16a denote front operation levers erected on the control boxes 15 and 15, and 45 and 45 denote operation levers. It is a pedal.

Then, both sides 46a, 46a of the boom bracket mounting fulcrum 7 on the step surface 46 of the control section 5 are extended forward so as not to protrude at least from the periphery of the machine frame body 3, and the operation pedals 45, 45 are extended. Has also moved forward, widening the driver's feet.

That is, as shown in FIG.
The bosses 45a, 45a connected to the lower part of the shaft 5 and the shafts 45b, 45b inserted through the bosses 45a, 45a extend forward.

In FIG. 7, 45c is a fulcrum bracket, and 45d is a link ball.

FIG. 8 shows a knob 48 attached to the upper end of the front operation lever 16a.
a and a lower body 48b are divided into two parts, and a ball-type joint 50 provided substantially at the center of the knob 48 is capable of tilting in all directions.

Then, the knob 48 is set to an arbitrary position.
The angle of the upper body 48a can be adjusted, and the upper body 48a can be fixed with screws 51.

Therefore, the driver and the front operation lever 16a,
The inclination of the knob 48 can be adjusted according to the positional relationship with the position 16a, and fatigue can be reduced by adjusting the knob 48 to the driving posture of the driver.

As shown in FIG. 9, a pivot 49 may be provided instead of the ball joint 50 so as to be rotatable. 52 is a fixing screw.

FIG. 10 shows a hose guide cylinder 57 disposed in the cross member 56 of the track frame 55 of the excavator B used in this embodiment.
Is also used as the reinforcing material.

The hose guide cylinder 57 has a more compact shape than before, and the space around the swivel joint 58 can be increased.

Further, the welding length can be reduced, the number of parts can be reduced, and the cost can be reduced.

Further, the hydraulic hose 61 is easily passed between the traveling motor 60 and the swivel joint 58, so that the assembling work of the machine is facilitated. In FIG. 10, 62 is a traveling frame,
63 is a rib.

FIG. 11 schematically shows a hydraulic circuit of the sirocco motor 66 provided in the excavating machine B according to this embodiment. The hydraulic circuit from the hydraulic pump P is divided into two systems, and one hydraulic system is used. A sirocco motor 66 is provided halfway. The sirocco motor 66 is used for cooling the radiator.

Then, an in-line check 67 of a predetermined set pressure is arranged on the hydraulic oil discharge side of the sirocco motor 66,
The pressure is taken out as a pilot pressure, and the control valve 18 is operated. In this embodiment, the predetermined pressure is 30 kg / cm ² , but the numerical value is not particularly limited.

Therefore, conventionally, it was necessary to provide a pressure reducing valve for the control valve 18. However, such a configuration can eliminate the pressure reducing valve, and can reduce the size and cost of the control valve 18. it can.

Further, when the sirocco motor 66 becomes abnormal, the operation of the control valve 18 becomes impossible and safety can be improved.

[0067]

According to the present invention, a pilot pump interlocking with the engine is provided in the middle of the pilot hydraulic path, and a hydraulic supply / discharge device for forcibly generating hydraulic pressure independently of the engine is provided. Accordingly, when the engine stops for some reason during the excavation work and the excavation work unit stops at a position higher than the ground surface, the excavation work unit can be lowered to the ground surface.

Therefore, it is possible to quickly avoid a dangerous state in which the excavation work section is stopped upward, and to check and inspect the engine and the like in a safe state in which the excavation work section is grounded on the ground surface. Repairs can be made. At this time, when the check valve for the supply / discharge device is provided in the middle of the supply / discharge device oil path connecting the downstream side of the hydraulic supply / discharge device and the pilot hydraulic path, the remote control valve can be broken. In addition, it is possible to reliably prevent the hydraulic reaction force from acting as an overload on the hydraulic supply / discharge device by the check valve for the supply / discharge device, thereby preventing damage to the hydraulic supply / discharge device.

Further, since the hydraulic supply / discharge device is composed of an electric pump using a battery as a power source and an operation switch of the electric pump, the driver can operate the switch quickly and easily simply by operating the switch. The excavation work part can be lowered.

Further, since the hydraulic supply / discharge device is constituted by a drive pump which can be manually operated and operation means of the drive pump, safety can be improved without adding cost. At this time, by providing the check valve for the supply / discharge device on the downstream side of the hydraulic supply / discharge device, it is ensured that the check valve for the supply / discharge device acts as an overload on the hydraulic supply / discharge device by the hydraulic reaction force. The manual operation of the hydraulic supply / discharge device can be smoothly performed.

[Brief description of the drawings]

FIG. 1 is a side view of an excavator equipped with a hydraulic pilot type operating device according to the present invention.

FIG. 2 is an explanatory view of a control section of the excavator.

FIG. 3 is a hydraulic circuit diagram of the hydraulic pilot type operating device according to the present invention.

FIG. 4 is a hydraulic circuit diagram of a hydraulic pilot type operating device according to another embodiment.

FIG. 5 is a hydraulic circuit diagram of a hydraulic pilot type operating device according to another embodiment.

FIG. 6 is a plan view of an excavator in another embodiment.

FIG. 7 is a sectional side view of the operation pedal.

FIG. 8 is an explanatory view of a knob.

FIG. 9 is an explanatory diagram of a modification example of a knob.

FIG. 10 is an explanatory diagram of a track frame.

FIG. 11 is a hydraulic circuit diagram of a sirocco motor.

[Explanation of symbols]

A Hydraulic supply / discharge device P Hydraulic pump P ₁ Pilot pump P ₂ Electric pump P ₃ Drive pump R Pilot hydraulic path S Operation switch a Hydraulic actuator e Engine 16 Operating lever 18 Control valve 23 Remote control valve

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsuhiro Ohashi 428 Enami, Onami, Okayama Pref. 72) Inventor Koji Yamada 428 Enami, Okayama City, Okayama Pref. Inside Sairei Industry Co., Ltd. (56) References JP-A-5-125746 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) E02F 9/20 E02F 9/24 F15B 11/08 F15B 20/00

Claims (3)

(57) [Claims] 1. A hydraulic pump (P) and a hydraulic actuator
(a) is connected via a control valve (18), and the operation of the hydraulic actuator (a) is controlled by the control valve (18), and is linked to the control valve (18) and the operating lever (16). A hydraulic pilot-type operating device for an excavator, which is provided in a pilot hydraulic path (R) while being connected to a remote control valve (23) and configured to operate the control valve (18) by pilot hydraulic pressure, In the middle of the pilot hydraulic path (R), the engine (e)
With arranging a pilot pump (P ₁₎ which is linked to, parallel with the engine (e) a hydraulic supply and discharge device (A) pumping the pilot to force generates a hydraulic pressure independently of the (P ₁₎
It is installed in a row, and the downstream side of the hydraulic supply / discharge device (A) and the hydraulic path for pilot
(R) to the supply / discharge device oil passage
A hydraulic pilot-type operating device for an excavator, comprising a check valve (28) . The hydraulic supply / discharge device (A) includes a battery (30).
The hydraulic pilot type operating device for an excavating work machine according to claim 1, comprising an electric pump (P ₂ ) powered by a power source and an operation switch (S) of the electric pump (P ₂ ). 3. The hydraulic supply / discharge device (A) according to claim 1, further comprising a manually operable drive pump (P ₃ ) and operating means for the drive pump (P ₃ ). Hydraulic pilot type operating device for excavator.