JPS59194104A - Fluid pressure actuator device - Google Patents

Abstract

PURPOSE:To reduce the number of solenoid valves to simplify the structure of a fluid pressure actuator device and to heighten the reliability of the device by driving a solenoid valve with a pulse current and controlling the duty ratio to control the operation speed of a hydraulic cylinder. CONSTITUTION:A fluid pressure actuator device includes a hydraulic cylinder 11, and the first and second solenoid valves 13, 14. The first solenoid valve 13 is mounted in an oil path 15 disposed between a pressure receiving chamber 11a of the hydraulic cylinder 11 and an oil pressure source 12, and the second solenoid valve 14 is mounted in an oil path 17 disposed between the pressure receiving chamber 11a and an oil tank 16. These solenoid valves 13, 14 are controlled to open and close by a control unit 18 having a drive pulse generator 26 for changing the duty ratio of repeat pulse signal, so that an operation rod 11c is located at such a position as to balance with the spring force of a spring 11b.

Description

[Detailed description of the invention] It is.

For example, hydraulic actuators are generally widely used as actuators for automatic clutch connection devices, etc., and as shown in FIG. 1a and a first electromagnetic valve 3 connected between the hydraulic power source 2 and the pressure receiving chamber 1.
a second solenoid valve 4 for releasing the hydraulic pressure, and an orifice 5
A third solenoid valve 7 is provided in the middle of a passage 6 having The operating frame 1c is positioned at a position where the spring force of the spring 1b within the hydraulic cylinder 1 is balanced. In this hydraulic actuator device, when the solenoid valve 3 is opened with the solenoid valves 4 and 7 closed, hydraulic pressure from the hydraulic source 2 is supplied to the pressure receiving chamber 1a, and the operation frame 1c is moved against the spring force of the spring 1b. Forced to move to the right. When the position sensor 8 detects that the operating frame 1c has moved to a desired position and the solenoid valve 3 is closed in response, the operating frame 1c will stop at that position. After that, when the operating frame 1c is returned to the left hand direction at high speed, the solenoid valve 4 is opened to rapidly reduce the hydraulic pressure in the pressure receiving chamber 1a.On the other hand, when the operating frame 1c is returned to the left hand direction at a slow speed, This is accomplished by opening the solenoid valve 7 instead of the solenoid valve 4 and gradually lowering the hydraulic pressure in the pressure receiving chamber 1a by the action of the orifice 5.

However, in this conventional device, the characteristics of each of the disposed fluid passages are different, and control is performed by a combination of a plurality of solenoid valves, so the idle running distance of the operating frame 1c caused by the operation of each solenoid valve is different. Therefore, it has the disadvantage that highly accurate positioning control cannot be expected. Furthermore, in order to improve the operating speed characteristics and the positioning accuracy, as mentioned above, when movement over a minute distance is required, an orifice is provided in the passage 6 where the flow rate of the oil is restricted. The opening and closing of the third solenoid valve 7 is controlled to obtain the desired minimum travel distance, and when moving at high speed, the opening and closing of the second solenoid valve 4 provided in the passage 9 with a large oil flow rate is controlled to move at a high speed. Since the position control was to be performed, as mentioned above, a passage for restricting the flow rate had to be provided separately, as well as a large number of solenoid valves, which made the configuration complicated, and the orifice for restricting the flow rate had to be installed separately. There was also the problem that there was a risk that dust and the like would become clogged and cause operational failures, resulting in lower reliability.

Therefore, the object of the present invention is to provide a highly reliable system that enables highly accurate positioning at controlled speeds from high to very slow, without providing an oriice and a corresponding solenoid valve in a hydraulic pressure adjustment mechanism. An object of the present invention is to provide a fluid pressure actuator device.

Features of the present invention include a fluid pressure cylinder, a fluid pressure supply source,
a first solenoid valve provided between the fluid pressure supply source and the pressure receiving part of the fluid pressure cylinder; a second solenoid valve for releasing pressure in the pressure receiving part; and a first or second solenoid valve. 0N10F
means for outputting a repetitive pulse signal for F driving;
means for changing the data ratio of the repetitive pulse signal, so that the operating speed of the fluid pressure cylinder can be continuously changed from very slow to high speed by adjusting the data ratio of the repetitive pulse signal. That's what I did.

Hereinafter, the present invention will be explained in detail with reference to the illustrated embodiments.

FIG. 2 shows an embodiment in which the hydraulic actuator of the present invention is used as an actuator for operating a clutch in an internal combustion engine vehicle. Fluid pressure actuator device 10
The hydraulic cylinder 11 and the first and second solenoid valves 13.1
4, the first solenoid valve 13 has an oil passage 1 disposed between the pressure receiving chamber 11a of the hydraulic cylinder 11 and the hydraulic pressure source 12.
On the other hand, the second solenoid valve 14 is provided in an oil passage 17 disposed between the pressure receiving chamber 1 ], a and the oil tank 16 . These electromagnetic valves 13 and 14 are controlled to open and close by a control unit 18, which will be described later, and thereby adjust the pressure in the pressure chamber 11a to some extent, and are operated to a position where the pressure and the spring force of the spring llb are balanced. The frame lie is positioned. Reference numeral 19 indicates the operation frame 11
This is a position sensor that outputs a position voltage signal V indicating the position of the operation frame 11c, and the position voltage signal v1 whose level changes depending on the position of the operation frame 11c is applied to the control unit 18. Data D1 indicating vehicle operating conditions (not shown), such as vehicle speed, engine speed, gear position, brake operation status, etc., is input to the control unit 18 from the operating condition detector 21, and the target position of the operating frame lie is input to the control unit 18. 5) The voltage signal V shown in FIG. 13 and 14 opening and closing are performed.

The control unit 18 converts each voltage signal V, , V, into digital data D, , D3, as shown in FIG.
An A/D converter 23.24 is provided to convert the data D1*D! +DS is input to the CPU 25, and a control program stored in the CPU 25 in advance is executed according to this information.

A flowchart of the clutch control program stored in CPU 25 is shown in FIG. This program is executed by interrupt processing in response to a gear change operation, and first, in step a, it is determined whether the shift lever position after the gear change is in the 1st gear (1st) or reverse (R) position. If the determination result in step a is r YES J, it is determined whether or not to start at Stella 7°b.

In the case of starting, a first control operation for latching the starting glue (6) is executed in step C, while in the case of not starting, a predetermined second control operation is executed in step d. Ru.

If the determination result in step a is r No J, determination is made in step e as to whether the gear position is 2nd speed (2nd), and if the determination result is r YES J, the result of further upshifting is determined. It is determined whether or not the gear position is in the third gear position (step f).
or a fourth control operation is performed (step g + h
).

If the determination result in step e is rNOJ, it is determined in step l whether or not the gear position is 3rd speed (3rd), and the fifth or sixth control operation is executed according to the determination result (step J .

k).

Each of the first to sixth control operations is executed according to control information read from a table prepared in advance, based on data indicating engine speed, vehicle speed, etc.

FIG. 5 shows a detailed flowchart illustrating the first control operation. To describe the control operation of the clutch 20 based on FIG.
Only in the case of o, the process proceeds to step C2, where it is determined whether the value of the engine speed N is decreasing. If the value of N is decreasing, there is a risk that the engine will stop.
Proceeding to step C3, the solenoid valve is operated so that the clutch 20 is in a clutch disengaged state. In the illustrated embodiment, the clutch 20 is connected when the operating frame 11c is fully moved in the direction of arrow A, and is disengaged when the operating frame 11c is fully moved in the direction of arrow B. Therefore, by opening the first solenoid valve 13 and closing the second solenoid valve 14, the shift latch 20 is brought into the disconnected state.

If the determination result in step C2 is "NO", it is determined in step C4 whether or not the brake is applied, and if the brake is applied, the brake is applied.
Proceed to step C3 and connect clutch 2 in the same way as in step C3.
If the brake is not applied, the process proceeds to Stella Zo C6 and the clutch 20 is connected.

Next, the operation of each electromagnetic valve 13.14 for connecting and disengaging the clutch 20 will be explained.The first and second electromagnetic valves 13.14 are respectively equipped with excitation coils 13a and 14a (see Fig. 2). As shown in FIG. 3, the first solenoid valve 13, which is a normally closed solenoid valve, is stimulated by applying the first excitation current 1 supplied from the CPU 25 to its excitation coil 13a. be opened. On the other hand, a second excitation current, which is an i4 pulse current output from the drive pulse generator 26, is applied to the excitation coil 14a of the second solenoid valve 14, which is a normally open solenoid valve. The drive A pulse generator 26 receives a control signal C output from the CPU 25.
When S is input, the duty ratio of the second excitation current generator is controlled by this control signal C8, and the second solenoid valve 14
The average opening degree of the second excitation current (1) is adjusted according to the duty ratio of the second excitation current (18).

According to such a configuration, the pressure in the pressure receiving chamber 11a can be changed at an arbitrary speed (9) by controlling the duty ratio of the second excitation current (2) using the control signal CS from the CPU 25. Therefore, the operation frame 11c
can be moved at a desired speed.

When moving the operation frame 11c a predetermined distance, the second
If the non-energizing time (the time during which the second electromagnetic valve 14 is opened) in one period T of the excitation current IIl is t, then the time required to move the above-mentioned fixed distance is t. The relationship between and the above time t& is expressed as follows (where a and b are constants).

That is, when moving the operation frame lie a predetermined distance, 1a
The size of 1. L□, t&2...tan, and the required time t at this time. 11 tog +...
... When ton is measured and the relationship between the two is plotted on a double logarithm (common logarithm) graph, it is shown as a -order curve.

That is, log (to) = a tog('',,') +
tag b---(2) holds true, and therefore, the relational expression shown by the first equation (10) t, = b·(ya)8 is obtained.

In this way, by controlling the duty ratio of the excitation current generator, the operating speed of the operating frame 11c can be freely and continuously set from high speed to slow speed, and therefore, the half-clutch can be set easily when starting the car. state, the duty ratio of the second excitation current I is reduced to slow down the engagement speed of the clutch 20. On the other hand, in the case of engagement of the clutch 20 after the car has been sufficiently accelerated, the data - The clutch can be engaged at a relatively high speed by increasing the tee ratio.

In FIG. 6, the state of the first control operation of the Stella 7''C shown in FIG.
It is shown at position P of a. Here, Pl is the position where the clutch 20 is in the disengaged state, P4 is the position where the clutch 20 is fully connected, and the area between P2 and P is the half-clutch zone. When the driving of the second solenoid valve 14 is started at T=T, the operation frame 11c
begins to move in the direction of arrow A and approaches P2 from Pl.

The position of the operation frame 11c is constantly monitored by the position sensor 19, and the duty of the second excitation current I2 is adjusted so that the clutch 20 is connected at a relatively high speed in the zone between Pl and P2. The ratio is controlled. T=T,
When P = P at 1, the clutch enters the half-clutch zone, so if the duty ratio is small, the clutch 2
0 becomes slow, and the clutch 20 is connected slowly.

When the clutch 20 is completely connected at T=T, the duty ratio is increased again, the clutch 20 is connected at a high speed, and the clutch 20 is completely connected at T=T.

Although the first control operation has been described in detail above, in the second to sixth control operations of the control program shown in FIG. To ensure smooth and quick connection,
Depending on vehicle speed, engine speed, gear position, and other operating conditions,
A so-called map calculation is performed to read out the optimum data ratio among the data ratios stored in advance in the ROM, and data ratio control of the second excitation current I8 is executed according to the read data. Connection speed is properly controlled.

In the above embodiment, a case has been described in which the operating speed of the clutch 20 is adjusted by changing the duty ratio of the excitation pulse current applied to a normally open solenoid valve, but the same applies to the case of a normally closed solenoid valve. control is possible. In the case of a normally closed solenoid valve, the valve is always closed with high oil pressure, and because of this oil pressure, even if current is applied to the excitation coil of the solenoid valve, it takes some time to overcome the oil pressure and open the valve. It becomes necessary. Taking this time as the valve response time t&, find the relationship between the duty ratio of the drive/arm current and the required time t. The following relational expression holds true.

According to such a configuration, when disengaging (13) the clutch 20, the first solenoid valve 13 is opened and the second solenoid valve 14 is closed to increase the pressure in the pressure receiving chamber 1a. When the operating frame 11c is fully moved in the direction of arrow B, for example, when a desired gear change is completed, any one of the first to sixth control operations is executed according to the flowchart shown in FIG. 20 connection operations are performed by the hydraulic cylinder 11. To connect the clutch 20, while the first solenoid valve 13 is kept closed, the second solenoid valve 14 is driven to open and close at a required duty ratio by the second excitation current generator 2. The clutch 20 can be connected at an optimum operating speed suitable for the operating conditions.

In this way, the operating speed of the hydraulic cylinder is adjusted by driving the electromagnetic valve with a pulse current and controlling its date ratio, so there is no need to provide an orifice or the like in the oil passage as in the past. Therefore, the number of solenoid valves can be reduced. Therefore, the problem of dust clogging in the orifice is solved, the structure is simplified, and reliability can be further improved.

In the above embodiment, the fluid pressure actuator device of the present invention is used as an actuator for connecting and disconnecting a clutch in an internal combustion engine vehicle, but it can also be widely applied to industrial robots, various positioning devices, etc. It is possible.

According to the present invention, as described above, the speed of the fluid pressure actuator can be continuously adjusted from slow to high speed with a single solenoid valve without providing an orifice or the like in the fluid passage. In addition to solving the problem of failures caused by tsutb, the configuration is simple because fewer solenoid valves are needed, and reliability is significantly improved, making it possible to perform more accurate control. be effective.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the structure of a conventional fluid pressure actuator device, FIG. 2 is a block diagram showing the structure of a vehicle device using the fluid pressure actuator device according to the present invention, and FIG. A detailed block diagram of the control unit shown in Fig. 3 is shown in Fig. 4.
FIG. 5 is a detailed flowchart of the first control operation in FIG. 4, and FIG. 6 explains the clutch connection operation in the device shown in FIG. 2. This is a graph for DESCRIPTION OF SYMBOLS 10... Fluid pressure actuator device, 11... Hydraulic cylinder, 11a... Pressure receiving chamber, 11b... Spring, ll
c... Operation frame, 12... Hydraulic pressure source, 13... First solenoid valve, 14... Second solenoid valve, 16... Oil tank, 1
8... Control unit, 21... Operating condition detector, 2
5...CPU. 26... Drive pulse generator, I... first drive current, work 2... second drive current. Patent applicant: Diesel Kiki Co., Ltd. Agent: Patent attorney: Masatoshi Takano -26- +1-″ o!'Ja!' - □〇-

Claims (1)

[Claims] 1. A fluid pressure cylinder, a fluid pressure supply source, a first electromagnetic valve provided between the fluid pressure supply source and a pressure receiving section of the fluid pressure cylinder, and a first solenoid valve for releasing the pressure of the pressure receiving section. 2
It is characterized by comprising a solenoid valve, means for outputting a repetitive pulse signal for driving the first or second solenoid valve 0N10FF, and means for changing the duty ratio of the repetitive pulse signal. Fluid pressure actuator device.