WO2004053337A1

WO2004053337A1 - Automatic booster for working machines

Info

Publication number: WO2004053337A1
Application number: PCT/JP2003/013365
Authority: WO
Inventors: Shuji Okano; Makoto Hasuike; Ikuhisa Sawada; Masanobu Kawanaka
Original assignee: Shin Caterpillar Mitsubishi Ltd.
Priority date: 2002-12-10
Filing date: 2003-10-20
Publication date: 2004-06-24
Also published as: JP3876220B2; JP2004190749A

Abstract

A pilot-operated type relief valve (16) is provided for the delivery passages (12a, 12b) of main pumps (11a, 11b), and a relief set pressure variable adjustment means (17) for variably adjusting the relief set pressure to a pressure higher than the initial relief set pressure is provided for the relief valve (16). Pump delivery pressure sensors (32a, 32b) are provided for the delivery passages (12a, 12b), and a head-side pressure sensor (33) is provided for a bucket cylinder (7a). A controller (31) outputs a signal to the relief set pressure variable adjustment means (17) to boost the initial relief set pressure to a higher relief set pressure in the case where the head-side pressure in the bucket cylinder (7a) is not less than the threshold with the pump delivery pressure continuing in its relief state for a given time. The oil pressure drive force is automatically increased during high load operation of a hydraulic shovel so as to improve operability and working efficiency.

Description

Automatic booster for fine work machine Nomoto invention is a white booster for a work machine that controls the U-pressure of the reflex valve whitely.

Husband

Back technique

As shown in FIG. 3, the hydraulic cylinder 3 is configured such that the upper rotating body 2 is turned relative to the lower traveling body 1.

A cap 3 and a font work device 4 are mounted on the upper rotator 2 in the sword, and the hood working device 4 is provided with a bobbin machine. The arm 5 is turned up and down by the dam 5a, and the arm is turned ft by the arm holder 6a.

6 and a socket 7 that is rotated by a socket cylinder 7a via a socket cylinder 7b are sequentially connected. It is a thing,

A hook 8 is provided at the connection between the case 7 and the packet link cage 7b so that the hook 7 can be used in addition to the excavation work by the case 7. 8 can also be used to suspend cargo W

It has become a shaman.

Conventionally, the hydraulic pressure level of the hydraulic pump is 3 ベル Conventionally, as shown in FIG. 4, 5 ヽ The discharge passage 1 2 of the main pump 1 1 Is connected to the supply port of the control valve 13 and the control motor 13 allows the left and right traveling motors and the upper motor of the lower carrier 1 to be connected. Hydraulic pressure of the rotating motor of the rotating body 2, such as the boom cylinder 5a, the arm cylinder 6a, the bolt cylinder 7a, etc. The hydraulic oil supplied to the unit is directionally controlled and the flow rate is controlled.

The upper limit of the pump discharge pressure is provided between the discharge passage 12 of the main pump 11 and the tank 14 via the check valve 15. A V-leaf valve 16 of a pipe-actuated type for setting the leaf-set pressure is provided. The port-operated relief valve 16 of this type receives the externally supplied pulse pressure oil and changes the preset load of the spring 16a. In this way, a set pressure adjuster 16b for variably adjusting the relief set pressure is provided, and the set pressure adjuster 16b of the resilient valve 16 is provided. In addition, a solenoid valve 21 for controlling the supply and discharge of the hydraulic pressure oil is provided.

For the solenoid valve 21 of this embodiment, there is a pump 24 for supplying the pilot oil to the pilot cylinder and a tank line for recovering the return oil from the pilot rotor. And 23 are connected. The solenoid 24 of the solenoid valve 21 is connected to a controller 25 for controlling the switching of the solenoid valve 21. This controller 25 is connected to a switching switch 26 installed in the cabinet 3 and operated by an operator. o

And, in the excavation work, the operator

By operating the switching switch 26 in 3, the controller A drive signal is output from the solenoid valve 25 to the solenoid 24 of the solenoid valve 21, and the solenoid valve 21 operates the pilot pump from the pump 22. A state in which the pilot pressure oil for increasing the VV — pressure is supplied to the section pressure regulator 16 b of the relief valve 16 of the model The main pump 11 switches from the main pump 11 to the control D 13 by the rise in the relief set pressure of the relief valve 16. The supplied operating hydraulic pressure is increased, the hydraulic driving force of each hydraulic actuator of the font work unit 4 is increased, and a high-load excavation operation can be performed.

On the other hand, if the switch is operated incorrectly by the switch 26 during running or turning, etc., the operation of the switch will be unpredictable. In order to prevent this, the pressure sensor detects each operation signal for operating multiple hydraulic actuators using a pressure sensor. Each work signal is separated into a drilling signal and a non-digging signal, and only when the drilling signal is detected and large drilling power is required, the page y Some valves are used to temporarily increase the pressure of the valve (V) (see, for example, Japanese Patent Publication No. 1 1 2 4 7 2 3 3).

According to the conventional technology, the operator has to manually operate the switching switch 26 every time the operator needs to do so. There is a problem that the work efficiency is lowered while giving annoyance. In addition, features to prevent unexpected operation and unpredictable operation due to erroneous operation of the disconnect switch 26 can be achieved.

The technology described in No. 2 3 3 requires ヽ a pressure sensor for detecting a large number of operation signals respectively. ヽ

>.

The controller separates each operation signal into a drilling signal and a non-digging signal, and when only the drilling signal is detected, a place P requiring large drilling power is required. Only for α, the pressure of the peri-valve valve is controlled so that the y-set pressure of the valve can be increased in a timely manner, so that the system configuration is controlled. Have complicated problems,

The present invention has been made in view of such a point, and when the work machine is under a high load operation, the driving force due to the working fluid pressure is automatically increased. Automatic booster with simple structure that can improve operability and workability

The provision of-is intended to be §1. Disclosure of the invention

Self-boosting equipment of the work machine of the present invention

The pressure of the working fluid discharged from the pump and supplied to the fluid pressure actuator is reduced by a small amount, i.e., the initial pressure. The initial V-section pressure and the V-offset pressure can be set to the high V-offset pressure, and the V-offset is applied to the V-offset pressure. Adjust the V-section pressure of the valve to the y-reset pressure, which is higher than the initial di-V-section h pressure. G The pump discharge pressure detector detects the pump discharge pressure discharged from the pump and the pump discharge pressure detector, and the pump discharge pressure is detected by the pump discharge pressure detection. When the pump discharge pressure reaches the initial dif- set pressure, it detects that the reflex shape has continued for one time. And a control means for outputting a signal for increasing the initial y-reset pressure to a higher re-set-reset pressure. The pump discharge pressure detected by the discharge pressure detection has reached the initial dirift valve pressure of the dirift valve. It is detected that the y-f state has continued for a fixed time. The control means determines from this state of reflex that the working machine is in a state of insufficient fluid pressure driving force, and judges To Ope les in the you output a signal Ru is raised to the initial V Li off cell V Li off cell Bok pressure of the high pressure Ri by a click Bok pressure versus Shi di di off valve to click Bok variable pressure regulating means

Even if the switch does not actuate the switching switch, it drives the fluid pressure actuator against the higher pump discharge pressure which is automatically boosted by the reflex valve. In order to improve the operability and work efficiency of the actuator by applying a force dynamically, the control means is also controlled through the pump discharge pressure detection. When the pump discharge pressure reaches the initial V re-set V-pressure, the VV-off state continues for a fixed period of time.シの成成成成ぴ I will.

Also, the working machine according to the present invention is a hydraulic cylinder equipped with a foot working device used for excavating and lifting work, and the hydraulic cylinder is a hydraulic cylinder. The head work equipment is provided with a head V side pressure detector for detecting the head K side pressure of a package V provided in a pocket work device, and a control means is provided.

TO

If the head-side pressure of the cylinder detected by the side pressure detection is not set to the threshold value,

V Whitening pressure booster for working machines that has a function to limit the boosting of one sector pressure in the V-section pressure variable adjusting means. When the pressure shovel performs digging work, the pressure on the head side of the packet cylinder becomes high, and when the lifting work is performed, The head and side pressure of the cylinder were increased so that the pressure did not become high. The control means was detected by V 'side pressure detection ¾5. / If the head pressure and lateral pressure of the cylinder are higher than the threshold value, it is determined to be a digging operation.

A signal to raise the reset pressure to the V reset pressure variable adjustment means was output.リフリジ昇圧リリリリ昇圧ヽヽヽ馬馬馬馬馬馬馬馬 Fluid pressure力 During the excavation work, the body pressure is reduced.

What.

Automatically increase the drive power of the

Improve work efficiency ¹ Improve work efficiency ¹ At the same time, it is possible to prevent unexpected and intense actuator operation during the lifting operation. However, the control means only monitors the pressure and side pressure of the nozzle cylinder through the pressure detector on the side of the head and excavates and suspends. Since the operation can be distinguished from the operation, the system configuration and control of the automatic booster can be simplified.

In addition, the controller of the commercial booster m of the work machine of the present invention has a function of releasing the boosted pressure of the relief set pressure in a fixed time. O If the load operation under the relief set pressure in the pressurized state continues for a fixed period of time, the high load operation is forcibly interrupted. O Ensures the durability of the work machine o

Brief description of drawings

The first is an implementation of the white dynamic pressure-increasing clothing of the work machine according to the present invention.

FIG. 2 is a circuit diagram showing the control method by the control means of the automatic booster, and FIG. 3 is a schematic diagram showing the work machine and the work machine. And FIG. 4 is a circuit diagram showing an example of a conventional dynamic booster of a machine.

Best mode for carrying out own invention

The present invention is shown in Fig. 1 to Fig. 3-The details of the embodiment are described below. The same parts as those of the conventional circuit, which were not shown in Fig. 4, are also described with one sign.

As shown in Fig.3, the hydraulic press, which is a working machine, is a front working device used for excavation work and hanging work. Have

That is, on the upper rotating body 2 that is rotatably mounted on the lower traveling body 1 with the HX, a font working device 4 is mounted together with the cap 3 on the upper rotating body 2. The front working device 4 is a boom 5 that is turned upward and downward by a pump cylinder 5 a as a fluid pressure actuator. The arm 6 is rotated by an arm cylinder 0a as a fluid pressure actuator, and the fluid pressure actuator is a fluid actuator. The socket 7 which is rotated via the socket y 7b by the socket y of the socket 7a is sequentially connected. The difference between the socket 7 and the socket V cage 7b is provided with a hook 8 force S.

With the emphasis on the excavation work by 7, it is also possible to suspend the luggage W using the hook 8.

-Fig. 1 shows the automatic pressure booster of the hydraulic shovel of ~ drawn from a pair of main pumps 11a, 1lb as pumps. The pair of outlet passages 12a and 12b are provided with a pair of valve ports of the inlet π-valve 13 and the respective outlets of the valves 13a and 13b.

Γ> Β With the knobs V 13a and 13b respectively connected to the port, the upper rotating body on the left and right of the lower traveling body 1 2 rotation motor, Pumsilin Hydraulic pressure of fluids such as fluid cylinder pressure, such as dam cylinder 6a, bucket cylinder 7a, etc. It controls the direction and flow rate of the operating hydraulic fluid as an operating fluid to be supplied to and supplied to the actuator.

Between the discharge passages 12a, 12b of the main pumps 11a, lib and the tank 14, the check pressure is increased through the check valves 15a, 15b. O Limiting, that is, a relief valve 16 of a port opening type that sets the relief set pressure o

The pilot operated relief valve 16 of this type receives the externally supplied pipe port pressure oil and changes the preset load of the spring 16a. In this way, a set pressure adjuster 16b is provided to adjust the relief set pressure, and each oil is discharged from the main pumps 11a and 11b and The relief pressure of the hydraulic oil supplied to the pressure actuator should be at least the initial relief pressure and the initial relief pressure. It can be set to a higher relief pressure than the cut pressure.

The relief pressure of the relief valve 16 is set to a higher pressure than the initial relief pressure for the set pressure regulator 16b of the relief valve 16. The VV one-set pressure variable adjustment means 17 that variably adjusts to the relief set pressure of

The VV one-set pressure variable adjustment means 17 is provided to the set pressure adjustment part 16 b of the y-shaped valve 16, Solenoid valve 21 that controls the supply and discharge of pressure oil. The pilot line 23 is connected to the tank line 23 for recovering the return oil from the pilot.

The Sir magnetic valve 21 is provided with a solenoid 24 for switching the movable valve body by the ¾ ^ 1. The output terminal of a controller 31 as a control means for switching and controlling the solenoid valve 21 is connected to the solenoid 24 of the solenoid valve 21 ο

In addition, the discharge passages 1 2a,

12b-The each ku! Pump 11a, detects the pump discharge pressure discharged from 1 lb force, and outputs an electric signal corresponding to the pump discharge pressure. Pump discharge pressure sensor 32a, 32b force S as output pressure detection 0

Now, the hydraulic working machine for the front work of the hydraulic shock absorber 4 V HX was used for the head of the packet cylinder 7a and the head for the side passage. Detect the head side pressure of the Ket cylinder 7a and press it to the head (ヽ t side pressure) Head 7 Output the la'5¾ signal Head and side pressure detection The head side pressure sensor 33 as a container is HX-separated.

A pressure switch that detects a pressure equal to or higher than a predetermined value and outputs a constant switch signal is used as a node and a side pressure detector for pump discharge pressure detection. Even good 0

Pump discharge pressure sensor 32a, 32b and head, lateral pressure The sensors 33 are respectively connected to the input terminals of the controller 31.

This controller 31 is in a relief state in which the pump discharge pressure detected by the pump discharge pressure sensors 32a and 32b is set to the initial relief set pressure. -Fixed time? V Detects that the pressure has

A function to output a signal for increasing the initial V-reset pressure to a higher pressure for the solenoid valve 24 of the solenoid valve 21 of 17 is provided. Yes, there is.

Further, in this connector π-31, the ν-side pressure of the bucket cylinder 7a detected by the head and the side pressure sensor 33 reaches the threshold value. If you don't want to play u,

A function of limiting the increase of the segment pressure by the V-unit pressure variable adjusting means 17 and a function of canceling the state of the increase in the di-V-unit pressure in a time interval are provided. O

Next, the control method by the front opening door 31 will be described with reference to the front opening chart shown in FIG. 2. The circled numbers shown in the numbers indicate the step numbers.

(step 1 )

The controller 31 responds to the pump discharge pressure from the main pumps 11a and lib detected by the pump discharge pressure sensors 32a and 32b. To the bucket cylinder 7a detected by the head side pressure sensor 33 and the electric signal And the electrical signal corresponding to the pressure on the pad's side.

(Step 2)

Pump discharge pressure sensor 32a at controller 31

When the pump discharge pressure detected by 32b reaches the initial reset pressure of the reflex valve 16, the V-iff condition has been maintained for a certain period of time, for example, two seconds or more. Judge whether or not

(Step 3)

In the judgment of Step 2, if the re-reflection state continues for more than the specified time (YES), high load work more than the initial reset pressure may be required. It is conceivable that the automatic boosting function is activated during the lifting work, for example, when the pressure on the K-side suddenly increases to the boom cylinder 5a. In addition, unexpected operations such as the lifting of the front working device 4 occur.In order to prevent this, if the operation is a digging operation, hanging Ri Oh Ru or because Ru was necessary force ^s Me you determine at work, Ri by the click K side pressure cell down support 33 to, in the work that has to hanging Ri to rise during the drilling work pressure etc.殆The pressure should not rise.

The head and side pressure in 7a are detected, and it is determined whether or not the head and side pressure in ^v are equal to or greater than a certain threshold.

(Step 4)

In the judgment of Step 2, the reflex state does not continue for longer than the fixed time.

Mouth (NO), there is, step 3 If the pressure on the head of the bucket cylinder 7a does not reach a certain threshold (N〇), the automatic pressure boosting function is regarded as a lifting operation. Do not work.

That is, the drive current is not output from the controller 31 to the solenoid 24 of the solenoid valve 21, and the relay of the knock-operated relief valve 16 is not output. The offset pressure is equal to the spring pressure.

It is maintained at the initial relief set pressure set by the preset load of 16a.

(Step 5)

The controller 31 determines that the pump discharge pressure has reached the initial relief set pressure in the judgment of step 2 and the jirrif state has continued for more than a predetermined time. If the pressure and side pressure of the bucket cylinder 7a are equal to or greater than a certain threshold value (YES) in the judgment of step 3, the strong hydraulic drive power is required. It is determined that this is a digging operation that requires a work, and the automatic boosting function is activated.

That is, the drive current is automatically output from the controller 31 to the solenoid 24 of the solenoid valve 21, and the solenoid valve 21 is shown in FIG. By switching from the position force to another position, the noise from the nozzle pump 22 via the solenoid valve 21 to the set pressure adjustment section 16b of the y-relief valve 16 Since the low pressure oil is supplied and the relief set pressure of the relief valve 16 rises, the main pumps 11a and 11b force 1 the discharge passage 12a

The operating hydraulic pressure supplied to the outlets 13a and 13b of the outlet 13a and 13b of the outlet 13 through the outlet 12b also increases, and the front 4 Increase the hydraulic drive force of each hydraulic actuator of work equipment 4

(Step 6)

The duration of the increase in the hydraulic drive force is limited to a fixed time, for example, several seconds to 10 seconds, in order to ensure the durability of the siber structure during excavation work. The controller 31 determines the elapse of this fixed time.

(Step 7)

After the passage of this one-time period, the controller 31 stops the output of the drive current to the solenoid 24 of the valve 21 and stops the solenoid valve 21. 1 Return to the position shown in the figure, return the V port pressure oil that had acted on the set pressure adjustment section 16 b to the tank 14, and set the relief valve 16. Return to the preset load of only spring 16a to end the pressure increase of the relief set pressure, but when necessary, the hydraulic drive Since the force can be increased, a good operating feeling can be given to the operator.

Next, the effects of ^v · ~~-automatic booster will be described.

At the time of excavation work with a hydraulic shovel, the pump discharge pressure detected by the pump discharge pressure sensors 32a and 32b decreases the initial value of the relief valve 16. When the relief set pressure has been reached and the state of relief has continued for a fixed period of time, the

3 The solenoid valve 21 is driven by the drive signal output from 1 to increase the leaf-set pressure of the port-operated relief valve 16. Pump discharge larger than usual The output pressure can be secured, and the hydraulic drive force of the front work 4 can be increased t! _C )

This increase in hydraulic driving force is caused by the fact that the pump discharge pressure has reached the initial relief set pressure of the relief valve 16, and the relief state has a fixed time of '1½ fee. In a situation such as excavation, it works when a small amount of hydraulic driving force is desired, and the operator is dissatisfied with the operation. Manual operation as shown in switch 26 (Fig. 4)

In addition, the hydraulic drive force can be automatically increased P when necessary, so that the switch switching work that has been given to the observer is troublesome. Can be eliminated, and operability and work efficiency can be improved.

In order to achieve this, the pump discharge pressure detected by the pump discharge pressure sensors 32a and 32b is changed to the initial relief set of the relief valve 16. The controller 31 that has detected that the pressure has reached the resilient state for a certain period of time is replaced by the controller 31.

Judging from the V-off state that the hydraulic drive force is not connected to the hydraulic drive force, the solenoid valve 21 of the relief set pressure variable adjusting means 17 is determined. Since a drive current is output to the node 24 to raise the initial V-reset pressure of the valve 16 to a higher pressure, the reset-set pressure. Even if the pelletizer does not operate the switch as in the conventional switching switch 26 (FIG. 4), the yy automatic valve 16 automatically increases the pressure. Higher pump discharge pressure It is possible to improve the operability and work efficiency of the operator by automatically increasing the driving force of the hydraulic actuator against 6 forces. it can .

In the case of _ and _, the outlet port 31 is connected to the pump discharge pressure sensors 32a and 32b. The pump discharge pressure is initially Vy The system configuration and control of the automatic pressure booster can be easily performed by simply monitoring whether or not the relief condition that has reached the pressure has continued for a certain period of time. : it can

Also, in order to prevent the automatic pressure boosting function from working during the lifting operation, the head side pressure sensor 33 is used to control the height of the nozzle 7a. The pressure on the pressure side is detected, and the increase in the pressure of the V-section can be automatically restricted.

You Do not be Chi, you hydraulic tio bell force ^s excavation work door of the

When the pressure on the head side of the container cylinder 7a is high, the suspension must be carried out. When the side pressure does not rise to a high pressure, the controller 31 is replaced with a head and a bucket series detected by the side pressure sensor 33. If the head-side pressure of the solder 7a is equal to or higher than the threshold value, it is determined that the work is excavation, and the solenoid valve 21 of the variable pressure means 17 is determined to be drilling work. A drive signal to increase the pressure of the cylinder is output, and if the work does not reach the maximum value, it is determined that the work can be performed by suspending the work. By not outputting the drive signal for boosting, the boost of the relief set pressure is limited, so the hydraulic actuator suitable for the work content The drive force can be obtained and the force S can be obtained. During the excavation work, the drive force of the hydraulic actuator is automatically increased, and the operability by the operator is improved. In addition to improving the work efficiency, it is possible to prevent unexpected and intense actuator operation during the lifting operation.

However, the controller 31 is a head and side pressure sensor.

掘削 Excavation work and suspension work can be distinguished only by monitoring the head and side pressure of the nozzle cylinder 7a through 3 掘削. It is a system configuration ぴ Easy control o

In addition, the controller 31 forcibly performs the high-loading excavation work when the load excavation work under the pressurized pressure of the press-fit is continued for a certain period of time. Since the suspension is performed, the durability of the hydraulic cylinder can be ensured.

In addition, during actual operation, if the operator does not want the dynamic boosting function of this device at all, stop this function under the initial fixed conditions of the controller 31. 0 Possibility of industrial use

The present invention is not limited to 油圧 hydraulic hydraulics only, but can also be applied to other working machines that work with hydraulic pressure.

Claims

The scope of the claims

1. The relief pressure of the working fluid discharged from the pump and supplied to the fluid pressure actuator should be reduced to a small <<initial V-offset pressure. A relief valve that can set a P pressure to a relief pressure V higher than the initial y relief set pressure,

V) Set the V y valve pressure of the V valve to a higher value than the initial relief V pressure. V offset pressure adjusting means,

A pump discharge pressure detector for detecting a pump discharge pressure discharged from the pump; and

Detects that the pump discharge pressure detected by the pump discharge pressure detection has been maintained at the initial relief set pressure for a fixed period of time. Control means for outputting a signal for increasing the initial one-set pressure to a higher relief-set pressure for each of the U-sets. When

Work machine white dynamic pressure booster characterized by having

2. The working machine is a hydraulic sheave equipped with a front work device used for excavation work and lifting work. The head and the side for detecting the side pressure of the set-up V Equipped with pressure detection,

If the head pressure of the detected cylinder cylinder is not set to the threshold value by the head side pressure detection, the control means is set to It has a function to limit the increase of the V reset pressure by the cut pressure variable adjustment means.

-The automatic booster for a working machine according to claim 1, characterized in that:

(3) The control means has a function of releasing the boosted state of the relief set pressure in a fixed time.

An automatic booster for a working machine according to claim 1 or claim 2, characterized in that: