JP2887502B2 - Driving method of hydraulic vane pump - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a variable displacement hydraulic vane pump used for a drive system of an automobile or the like, and a method of driving the same.

[Prior Art] FIG. 4 is a system diagram showing a conventional clutch hydraulic control circuit.

In FIG. 4, a piston 7c of the hydraulic actuator 7 is linked to a clutch provided between the engine and the transmission (not shown) of the automobile, and a displacement chamber 7a of the hydraulic actuator 7 is connected to a pipeline 7e. It is connected to the discharge hole of the gear pump 11 via the switching valve 3 and the high hydraulic line 11a, and the pilot line 3a and the high hydraulic line in the switching valve 3 are connected.
A switching valve 5 is interposed between the switching valve 11a and the switching valve 11a. The gear pump 11 is driven by an engine in an automobile.

The displacement chamber 7b of the hydraulic actuator 7 is connected to the reservoir 4 via the low hydraulic pressure line 7d and the back pressure valve 6,
The back pressure valve 6 is a pressure setting valve that regulates the oil pressure in the low oil pressure line 7d to be constant, and the oil pressure in the high oil pressure line 11a is provided between the high oil pressure line 11a and the low oil pressure line 7d. A hydraulic adjustment valve 2 for controlling is provided.

The operation of the conventional configuration shown in FIG. 4 is as follows.

In a so-called engine idling state where the engine is operating before the vehicle starts, the switching valve 5
The solenoid 5a is turned off and its switching position is 5A. As a result, the pilot line 3a opens to the reservoir 4 and the switching position of the switching valve 3 is 3B.

At this time, the instruction to the solenoid 2b in the hydraulic pressure adjusting valve 2 is in a state where the space between the high hydraulic pressure line 11a and the high pressure line 2a is maximized, that is, the hydraulic pressure in the high hydraulic pressure line 11a is set to the minimum value (back pressure (A value of the hydraulic pressure somewhat higher than the set hydraulic pressure of No. 6).

With the above setting, the displacement chamber 7a is opened to the reservoir 4 through the switching valve 3, and the pressure oil discharged from the gear pump 11 is sent to the low hydraulic line 7d through the hydraulic pressure adjusting valve 2 and the line 2a, The hydraulic pressure of the low hydraulic pressure line 7d is set to a low pressure of about 2 atm by the back pressure valve 6, and the pressure oil in the low hydraulic pressure line 7d is sent to the displacement chamber 7d by pressure, returning the piston 7c to the right to disengage the clutch. It is in a disconnected state.

When the vehicle is started from this engine idling state, the driver depresses the accelerator pedal.However, in conjunction with the operation of the accelerator pedal or the increase in the engine speed due to the depression of the accelerator pedal, etc., The solenoid 5a is turned on, and the switching valve 5 is set to the switching position 5B.

Then, since the oil pressure in the high oil pressure line 11a communicates the branch line 5b and the switching valve 5 with the pilot line 3a, the oil pressure generated in the pilot line 3a by the communication sets the switching valve 3 to the switching position 3A.

In this state, the command value to the solenoid 2b is increased so that the oil pressure in the high oil pressure pipeline 11a becomes a function of the accelerator pedal operation or the engine rotation speed. As a result, the increase in oil pressure in the high oil pressure line 11a increases the oil pressure in the displacement chamber 7a via the switching valve 3 and the line 7e,
Since the increase in the oil pressure is higher than the oil pressure in the displacement chamber 7b, the piston 7c is shifted to the left to engage the clutch, and the engagement force is increased following the engagement.

In this way, the vehicle is started by engaging the clutch,
When the power from the engine is continuously transmitted to the drive wheels, the instruction value to the solenoid 2b is kept at the high value, that is, the hydraulic pressure in the high hydraulic pressure line 11a is kept at a high value.

Conversely, when the clutch is disengaged during a gear change operation or the like, the switching valve 5 is disengaged in the same manner as during idling.
May be switched to the switching position 5A and the value indicated to the solenoid 2b may be set to the lowest value.

[Problem to be Solved by the Invention] The conventional configuration described above has the following problems.

As can be understood from the above description of operation, in the state where the clutch is engaged, that is, in the state where the piston 7c is pressed to the left and the piston 7c is fixed at the pressed left position, It is sufficient that sufficient hydraulic pressure is generated in the displacement chamber 7a to maintain the pressure.
No inflow of pressurized oil has occurred.

This means that in this state, the pressure oil discharge amount from the gear pump 11 may be small enough to keep the oil pressure required for clutch engagement.

However, since the gear pump 11 is a fixed displacement type, even in a state where such a clutch is engaged and held,
Regardless of the operation state, the discharge amount which is always at the maximum value is continuously discharged to the high hydraulic pressure line 11a as the discharge line.
In addition, the clutch engagement time is relatively long.

This means that unnecessary hydraulic energy is consumed in this clutch engaged state.

Further, in a circuit in which such a state that the required pressure oil amount may be small, in order to eliminate such a hydraulic energy loss, such a fixed displacement type gear pump 11 is replaced with a variable displacement type hydraulic pump. What is necessary is just to substitute. That is,
What is necessary is just to set the value of the displacement of the hydraulic pump corresponding to the pump discharge amount at which the high hydraulic pressure line 11a always becomes the required hydraulic pressure in each state.

However, in general, when such a variable displacement hydraulic pump is employed, there is a disadvantage that the entire apparatus becomes expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a variable displacement hydraulic vane pump used in a hydraulic device in which the entire device is inexpensive and does not cause the above-described hydraulic energy loss, and a driving method thereof.

[Means for Solving the Problem] In the means of the first aspect, the hydraulic actuator (7) guides the hydraulic pressure from the low hydraulic pressure line (7d) acting in a direction to disconnect the clutch from the engine. And the other displacement chamber for selectively guiding the hydraulic pressure of the high hydraulic pressure line (1a) acting in the direction of engaging the clutch in opposition to the hydraulic pressure of the one displacement chamber (7b). (7a), the other displacement chamber (7a) and the high hydraulic pressure line (1a)
And a switching valve (3) for selectively communicating the other displacement chamber (7a) to either the high hydraulic pressure line (1a) or the reservoir (4). Between the hydraulic line (7d) and the reservoir (4), a back pressure valve (6) for setting the oil pressure of the low hydraulic line (7d) to be constant is provided, and the back pressure valve (6) is connected to the high hydraulic line (1a). A hydraulic adjustment valve (2) for controlling the hydraulic pressure of the high hydraulic line (1a) is provided between the low hydraulic line (7d) and a variable displacement hydraulic vane pump (1). Each of the grooves (1k) cut in the radial direction at the plurality of positions in the circumferential direction of the driven rotor (1c) and the vanes (1k) are respectively slidable in the radial direction. 1d), and the tip of each vane (1d) is slidably in contact with the cam ring (1b). The rotor (1c) and the cam ring (1b)
Of the displacement chambers (1g, 1h) formed by the above, the displacement chamber (1g) on the suction side which is performing the expansion stroke by the rotation communicates with the reservoir (4) through the suction port,
The discharge-side displacement chamber (1h) performing a compression stroke by the rotation communicates with the high-hydraulic-pressure pipe (1a) via a discharge port, and forms the discharge-side displacement chamber (1h). Once on the radial back of the vane (1d),
The hydraulic pressure from the high hydraulic pressure line (1a) after being increased to a predetermined rotation speed is guided, and the vane (1d) forming the suction side displacement chamber (1g) is provided on the radially rear surface of the vane (1d). It is characterized in that hydraulic pressure is guided from the low hydraulic pressure line (7d) after the engine is once increased to a predetermined rotational speed.

According to the means of claim 2, each of the grooves (1) formed at a plurality of positions in the circumferential direction of the rotor (1c) driven by the engine and cut in the respective radial directions at the plurality of positions.
k), each of the vanes (1
d), the tip of each vane (1d) slidably contacts the cam ring (1b), and each displacement chamber formed by the vane (1d), the rotor (1c) and the cam ring (1b). Of (1g, 1h), the displacement chamber (1g) on the suction side, which is performing the expansion stroke by the rotation, communicates with the reservoir (4) through the suction port, and the discharge side, which performs the compression stroke by the rotation, The displacement chamber (1h) communicates with the high hydraulic pressure line (1a) via a discharge port, and the hydraulic pressure from the high hydraulic pressure line (1a) is used as a hydraulic pressure source in the radial direction of the vane (1d). A hydraulic vane pump (1) led to the back of the engine for a predetermined time immediately after the start of the engine and before the hydraulic oil in the high hydraulic pressure line (1a) is used as hydraulic energy. Rotation speed to a certain speed It is characterized by that.

[Operation] In the hydraulic vane pump (1), when the rotor (1c) is driven by the engine, centrifugal force acts on the vane (1c) by the rotation.

However, in the state where the rotation of the engine idling is initially low in the driving, sufficient centrifugal force is not generated in the vane (1d).

Therefore, in such an engine idling state, the vane (1d) is brought into contact with the cam ring (1b) by the small centrifugal force due to the sliding resistance between the vane (1d) and the groove (1k). I can't jump out.

Here, the hydraulic vane pump (1) is connected to the high hydraulic pipeline (1a).
The reason why the pressurized oil is discharged is that the displacement chamber (1h) of the hydraulic vane pump (1) performs the compression stroke by the rotation of the rotor (1c).

The displacement chamber (1h) in the hydraulic vane pump (1) is formed by the cam ring (1d) at the tip of the vane (1d).
b) must be touched.

Therefore, as described above, when the engine rotation speed at the time of starting the engine is low and the vane (1d) has not yet come into contact with the cam ring (1b), the displacement chamber (1g, 1h) has not been formed yet.

Therefore, the hydraulic oil cannot be discharged from the hydraulic vane pump (1) to the high hydraulic pipeline (1a) when the engine is started and the engine rotational speed is low.

In the present invention, in a state after the engine is once increased to a predetermined rotational speed, one side of the vane (1d) forming the discharge-side displacement chamber (1h) is provided on the radially rear surface of the vane (1d). The hydraulic pressure generated in the high hydraulic line (1a) is guided, while the displacement chamber on the suction side (1g)
The hydraulic pressure generated in the low hydraulic pressure line (7d) is guided to the radially rear surface of the vane (1d) forming the hydraulic pressure.

 This means the following.

Once the engine speed is increased to a predetermined rotation speed, the rotation speed of the rotor (1c) increases, and the centrifugal force of the vane (1d) also increases.

As a result, the vane (1d) jumps out due to the increased centrifugal force until its tip comes into contact with the cam ring (1b), thereby forming a displacement chamber (1g, 1h) of the hydraulic vane pump (1).

Thus, the displacement chamber (1) of the hydraulic vane pump (1)
g, 1h), the hydraulic oil is discharged from the hydraulic vane pump (1) to the high hydraulic line (1a), and the hydraulic oil is discharged through the hydraulic adjusting valve (2) to the low hydraulic line (7d). ).

When the hydraulic pressure is generated in the high hydraulic pressure line (1a) and the low hydraulic pressure line (7d) in this way, on the other hand, the radial back surface of the vane (1d) forming the discharge side displacement chamber (1h) The hydraulic pressure from the high hydraulic pressure line (1a) is guided to the vane (1d) which forms the displacement chamber (1g) on the suction side.
The hydraulic pressure from d) is led.

The hydraulic pressure guided to the back of the vane (1d) presses each vane (1d) in a direction to assist the centrifugal force. By this pressing, each vane (1d) is pushed up in the radial direction, and the tip of the vane (1d) surely comes into contact with the cam ring (1b).

As a result, the displacement chamber (1g, 1h) of the hydraulic pump (1)
Is formed.

Displacement chamber (1g, 1h) of such a hydraulic pump (1)
Once formed, even if the rotational speed of the engine drops again to the idling state and the centrifugal force of the vane (1d) decreases, the hydraulic pressure of the high hydraulic line (1a) generated The vane (11d) is pressed toward the cam ring (1b) to continuously form the displacement chambers (1g, 1h) of the hydraulic pump (1) and to continuously discharge the hydraulic pressure to the high hydraulic pipeline (1a).

Thus, the hydraulic vane pump (1) can be used even when the engine is idling and the centrifugal force of the vane (1d) is reduced, and the hydraulic vane pump (1) is used.
Is a variable displacement type, so that in the clutch hydraulic control circuit, the hydraulic vane pump (1) can always adjust and discharge the required amount of pressure oil.

On the side of the displacement chamber (1h) in the compression stroke, the high hydraulic pressure in the displacement chamber presses the vane (1d) radially inward, and the high hydraulic pressure is applied to the back of the vane (1d). The high-pressure oil in the pipeline (1a) is guided, and on the side of the displacement chamber (1g) in the expansion stroke, the low oil pressure in the displacement chamber pushes the vane (1d) radially inward, and the vane (1d) is pressed against the vane (1d). The low-pressure oil in the low-pressure hydraulic line (7d) is led to the back of the vane (1d), and a hydraulic balance is maintained for each of the high-pressure side and the low-pressure side.

The hydraulic vane pump (1) discharges the pressurized oil to the high hydraulic line (1a) because the displacement chamber (1h) performs a compression stroke, and the displacement chamber (1h) performs the compression stroke.
h) The vane (1d) has a cam ring (1b)
Is not formed unless it is in contact with.

In addition, when the engine rotation speed at the time of starting the engine is low and the vane (1d) cannot yet come into contact with the cam ring (1b), the displacement chamber (1) of the hydraulic pump (1)
g, 1h) is not formed yet as in the case of claim 1.

In the present invention, the rotation speed of the engine is increased to a certain rotation speed for a predetermined time immediately after the start of the engine and before the hydraulic oil in the high hydraulic pressure line (1a) is used as hydraulic energy. .

When the rotation speed of the engine is increased to a certain rotation speed for a predetermined time, the rotation speed of the rotor (1c) increases and the centrifugal force of the vane (1d) also increases.

As a result, due to the increased centrifugal force, the vane (1d) jumps out until its tip contacts the cam ring (1b), and a displacement chamber (1g, 1h) of the hydraulic vane pump (1) is formed.

When the displacement chambers (1g, 1h) are formed in this way, the hydraulic oil is discharged from the hydraulic vane pump (1) to the high hydraulic pipeline (1a).

When pressure oil is discharged to the high hydraulic pressure line (1a), the hydraulic pressure from the high pressure hydraulic pressure line (1a) is applied to the vane (1a).
d) is guided to the radial back.

The hydraulic pressure guided to the back of the vanes (1d) pushes each vane (1d) in a direction to assist the centrifugal force. By this pressing, each vane (1d) is pushed up in the radial direction, and the tip of the vane (1d) surely comes into contact with the cam ring (1b). As a result, a displacement chamber (1g, 1h) is formed.

The hydraulic chamber (1a) generates hydraulic pressure and the displacement chamber (1g, 1
h) is formed once, even if the rotational speed of the engine is reduced again to the idling state and the centrifugal force of the vane (1d) is reduced, the generated high hydraulic pipeline (1a) The hydraulic pressure presses the vane (1d) toward the cam ring (1b), continuously forming the displacement chambers (1g, 1h), and continuously discharging the hydraulic pressure to the high hydraulic pressure pipeline (1a).

[Examples] Hereinafter, the present invention will be described based on examples.

FIG. 1 is a system diagram showing a hydraulic control circuit of a clutch according to an embodiment of the present invention, and FIG. 2 is a side sectional view of a variable displacement hydraulic vane pump 1 in FIG. Things.

The hydraulic control circuit of the clutch shown in FIG. 1 is different from the conventional hydraulic control circuit shown in FIG. 4 in that the gear pump 11 in FIG. 4 is replaced by a variable displacement hydraulic vane pump 1 in FIG. In addition, a throttle passage 8 is provided between the high hydraulic line 1a and the low hydraulic line 7d, and a groove in the hydraulic vane pump 1 is provided from the low hydraulic line 7d via a branch line 1i.
1f (FIG. 2) is communicated with the low hydraulic pressure, and the high-pressure hydraulic line 1a serving as the discharge line of the hydraulic vane pump 1 is connected to the groove 1e (second
(Fig.) Is that the high hydraulic pressure is communicated.

The grooves 1f and 1e are respectively provided on side plates of the rotor 1c in FIG. 2 (in the illustration of FIG. 2, both side plates provided on both sides of a back surface side portion of the rotor 1c and an upper surface side portion of the rotor 1c). It is provided to be open to 1c.

As shown in FIG. 2, the hydraulic vane pump 1 has the structure of a normal hydraulic vane pump, and each vane 1d guided by the cam ring 1b to move in the radial direction is provided in each groove 1k cut into the rotor 1c. Inserted so that it can slide in the radial direction,
Each displacement chamber 1g on the suction side formed by each vane 1d, the rotor 1c and the cam surface 1b is located on the right side of the line connecting
It communicates with a low-pressure port (not shown), which communicates with the reservoir 4 in FIG.

Further, each vane 1d, which is located on the left side of the line connecting a-b,
Each displacement chamber 1h on the discharge side formed by the rotor 1c and the cam surface 1b communicates with a high-pressure port (not shown), and the high-pressure port communicates with the high-hydraulic-pressure line 1a in FIG.

In addition, the cam ring 1b in FIG. 2 can be controlled in an ab direction by an actuator (not shown) to change the displacement of the displacement chambers 1g and 1h, and is a so-called variable displacement type. The control is based on the hydraulic pressure of the high hydraulic pressure line 1a as a feedback signal.
The displacement is controlled so that the oil pressure is equal to the set oil pressure.

 The operation of the above configuration will be described below.

First, when the engine is started, the hydraulic vane pump 1 linked to the engine is also driven, and the hydraulic vane pump 1 pumps hydraulic oil from the reservoir 4 and transfers the pumped oil to the high hydraulic pipeline 1a as a discharge pipeline. Try to eject.

However, at the idling rotational speed at which the engine is started, the rotational speed of the rotor 1c is low, so that the centrifugal force of the vane 1d due to the rotational speed is still small. As a result, especially when the viscosity of the hydraulic oil is high due to the low temperature of the hydraulic oil in the reservoir 4,
The small centrifugal force may not be able to urge the vane 1d to the cam ring 1b against the viscous frictional resistance of the working oil between the groove 1k and the vane 1d.

FIG. 3 is a flowchart showing the control of the clutch hydraulic pressure control device which copes with such a case, and its operation is as follows.

Calculation E1: The calculation by the computer is started in conjunction with the switch-on of the engine.

Operation E2: Initialize the computer.

Arithmetic operation E3: The rotational speed n of the engine is detected.

Arithmetic E4: It is determined whether or not the rotation speed n of the engine has reached a predetermined rotation speed no. That is, it is determined whether or not the engine has been started by switching on the engine.

If the above determination is negative, the process returns to the calculation E3 to continue detecting the engine speed n.

Arithmetic E5: If the determination in arithmetic E4 is yes, the fuel supply to the engine is increased until the engine rotational speed n becomes a constant rotational speed.

Arithmetic E6: Time measurement from the start of the fuel supply increase is performed.

Calculating E7: that time measurement is a determination of whether the elapsed predetermined time T _0. If the determination is negative, the process returns to E6.

Arithmetic E8: If the determination in the arithmetic E7 is yes, the fuel supply to the engine is returned to the fuel supply amount corresponding to the original idling rotational speed, and the control is shifted to the following control for entering a normal running state. .

Here, the fact that the engine speed is temporarily increased to a certain high speed as described above before the control of the normal running means the following.

Before the pressure oil in the high hydraulic pressure line 1a is used as hydraulic energy for clutch control, if the rotation speed of the engine is increased to a predetermined rotation speed, the rotor 1c driven by the engine also rotates for a certain period of time. Increase. As a result, the centrifugal force of the vane 1d resulting from the rotation rise also increases, and each vane 1d is surely urged to the surface of the cam ring 1b. As a result, the displacement chambers 1g and 1h in the hydraulic vane pump 1 are reliably formed. Thus, a state in which pressure oil can be discharged is formed in the high hydraulic pressure line 1a, and hydraulic pressure is generated in the high hydraulic pressure line 1a.

Once the hydraulic pressure is thus formed in the high hydraulic pressure line 1a, the hydraulic pressure is applied to each vane 1d via the branch line 1i or 1i.
The vanes 1d are forcibly urged radially outward by the introduced hydraulic pressure.

As a result, each vane is
1d continues to be urged to the cam ring 1c,
As long as the rotation exists, the hydraulic pressure is generated in the high hydraulic pressure pipeline 1a, and the urging force continues to exist.

Therefore, even if the rotational speed of the engine decreases and the centrifugal force generated in the vane 1d decreases thereafter, the generated hydraulic pressure causes the vane 1d to move the vane 1d through the groove 1e or 1f. , Whereby the tip of the vane 1d keeps in contact with the cam ring 1b.

 Hereinafter, the operation at the time of normal traveling control will be described.

In the idling state where the engine is started, the operation of the switching valves 3 and 5 is the fourth operation in the conventional example.
It is the same as the case of the figure. In other words, before the vehicle starts moving, the switching valve 5 is set to the switching position 5A, whereby the switching valve 3 is set to the switching position 3B, so that the displacement chamber 7a is opened to the reservoir 4.

At the same time, the pressure oil in the high hydraulic pressure line 1a is supplied to the low hydraulic pressure line 7d via the hydraulic pressure adjusting valve 2 and the throttle flow path 8, so that the low hydraulic pressure line 7d is connected to the back pressure valve 6d. Is set to a constant low pressure state. Therefore, while the displacement chamber 7a is open to the reservoir 4, the pressure oil in the low hydraulic pressure line 7d is fed to the displacement chamber 7b, and the piston 7c disengages the clutch (not shown).

In the case of this engine idling state, the command value to the solenoid 2b is set to the lowest value,
As a result, the amount of communication from the high hydraulic line 1a to the line 2a via the hydraulic pressure adjusting valve 2 increases, and the hydraulic pressure in the high hydraulic line 1a becomes a low value close to the set value of the back pressure valve 6. It has become.

From this state, when transmitting the power of the engine to the drive wheels, the driver depresses the accelerator pedal, but in conjunction with the operation of the accelerator pedal or an increase in the engine speed due to the operation. 4, the switching valve 5 is switched to the switching position 5B, whereby the switching valve 3 is switched to the switching position 3A.

At the same time as the switching of the switching valve 3, the command value to the solenoid 2b increases in conjunction with the operation of the accelerator pedal or the increase of the engine rotation speed, and the hydraulic pressure of the high hydraulic line 1a increases. In this case, the low hydraulic line 7d
That is, since the oil pressure in the displacement chamber 7b side is a constant low pressure, the oil pressure in the high hydraulic pressure line 1a increases, and the increase increases the oil pressure in the displacement chamber 7a through the switching position 3A and the line 7e. Then, the rising hydraulic pressure shifts the piston 7c to the left due to a difference from the hydraulic pressure in the displacement chamber 7b to engage the clutch.

Further, after the engagement, the increase in the oil pressure of the displacement chamber 7a increases the engagement force to a required value, and enables power transmission from the engine to the drive wheels via the clutch.

In the clutch engagement completed state, that is, in the state where the shift of the piston 7c to the left is stopped, the command value to the solenoid 2b becomes a high value, and the hydraulic adjustment valve 2
The communication from 1a to conduit 2a is almost closed. Moreover, in this case, the transition stop of the piston 7c causes the high hydraulic
The flow of the pressure oil flowing from the 1a side into the displacement chamber 7a via the pipe 7e is stopped, and there is no pressure oil flowing from the low hydraulic pressure pipe 7d to the displacement chamber 7b.

Therefore, in this state, the amount of oil discharged from the hydraulic vane pump 1 is very small enough to maintain the oil pressure of the high hydraulic line 1a at the control set value by controlling the displacement of the hydraulic vane pump 1. I have to.

That is, in this state, almost all of the hydraulic oil discharge amount of the hydraulic vane pump 1 is changed from the high hydraulic line 1a to the throttle passage 8 and the low hydraulic line 7d because the hydraulic pressure adjusting valve 2 is almost closed at this time. Inflow. The pressure oil that flows in is a low hydraulic line
This is only the amount by which the back pressure valve 6 leaks pressure oil to the reservoir 4 in order to maintain the set pressure of 7d.

Thus, the hydraulic pressure regulating valve 2 stops the flow from the high hydraulic pressure line 1a to the low hydraulic pressure line 7d, and the hydraulic vane pump 1
Even if the displacement control is such that the discharge of pressure oil to the high hydraulic line 1a is minimized, the hydraulic pressure set by the back pressure valve 6 exists in the low hydraulic line 7d.

In this case, the pressure oil supplied through the throttle flow path 8 to maintain the set hydraulic pressure depends on the condition for maintaining the set pressure on the downstream side of the throttle flow path 8 (low hydraulic line 7d). The discharge flow rate of the hydraulic vane pump 1 is sufficient to satisfy the hydraulic pressure required for the high hydraulic pipeline 1a.

In FIG. 2, on the low pressure port side, low oil pressure is introduced from the low oil pressure line 7d to the back of each vane 1d,
On the high pressure port side, a high hydraulic line is provided on the back of each vane 1d.
High hydraulic pressure from 1a is introduced.

This means that even if the low hydraulic pressure of the low hydraulic pressure line 7d is introduced to the back of all the vanes 1d, or if the high hydraulic pressure of the high hydraulic pressure line 1a is introduced to the back of all the vanes 1d, It is useful in urging the vane 1d radially outward.

However, on the low pressure port side, the low oil pressure in the displacement chamber 1g acts on the vane 1d to press the vane 1d radially inward, and on the high pressure port side, the displacement chamber
The high oil pressure at 1h acts on the vane 1d to press the vane 1d radially inward. Besides, cam ring of vane 1d
Considering the abrasion and sliding resistance to 1b, there is a problem that it is desirable to always apply a constant radial pressing force to the vane 1d regardless of the side of the low-pressure port or the high-pressure port.

For this reason, on the low pressure port side, the low hydraulic pressure of the low hydraulic pressure line 7d is introduced to the back of the vane 1d on the low pressure port side, and the component of the hydraulic pressure of the low pressure port acting on the vane 1d is offset by the same low hydraulic pressure. ing. On the other hand, on the high pressure port side, the high oil pressure of the high oil pressure pipeline 1a is introduced into the back of the vane 1d on the high pressure port side, and the component acting on the vane 1d due to the oil pressure of the high pressure port is canceled by the same high oil pressure. Is what it is.

In the above embodiment, the hydraulic control device for the clutch has been described as an example. However, in the present invention, when the hydraulic vane pump is driven by the engine, the vane 1d is attached to the cam ring 1b by the discharge pressure of the hydraulic vane pump 1 itself. This can be applied to all drives to be driven.

[Effects of the Invention] 1) Vane 1d to assist centrifugal force acting on vane 1d
Means for guiding the hydraulic pressure to the radial rear surface of
In both cases, instead of providing another independent hydraulic pressure source and guiding hydraulic pressure from the hydraulic pressure source, the discharge pressure of the hydraulic vane pump 1 itself can be used. This simplifies the entire apparatus and reduces the unit price of the entire apparatus.

2) The means for guiding the hydraulic pressure to the radially rear surface of the vane 1d is the hydraulic vane pump according to claim 1, since the hydraulic pressure generated in the high hydraulic pipeline 1a after the rotational speed of the rotor 1c is once increased is used. Even if the rotation speed of the engine that drives the engine 1 becomes the idling low-speed rotation again and the centrifugal force acting on the vane 1d decreases, the tip of the vane 1d continues to contact the cam ring 1b, and the hydraulic oil discharge of the hydraulic vane pump 1 continues. to enable.

As a result, the hydraulic vane pump 1 which is inexpensive and can perform variable displacement control can minimize the pressure oil discharge amount in a state where the clutch is not operated, that is, in a state where almost no control pressure oil is required, and the hydraulic vane pump 1 1 can be reduced.

3) In the first aspect, the means for guiding the hydraulic pressure to the radially back side of the vane 1d includes: a high-pressure side serving as a discharge side and a low-pressure side serving as a suction side of the hydraulic vane pump 1; Since the hydraulic pressure of the high hydraulic line 1a is guided and the hydraulic pressure of the low hydraulic line 7d is guided on the low hydraulic side to achieve hydraulic balance, when the tip of the vane 1d slides in contact with the cam ring 1b. Can be maintained at an appropriate value.

4) In claim 2, the tip of the vane 1d continues to contact the cam ring 1b even if the rotational speed of the engine that drives the hydraulic vane pump 1 becomes the idling low-speed rotation again and the centrifugal force acting on the vane 1d is reduced. The hydraulic vane pump 1 enables discharge of pressure oil.

This is the case where it is necessary to drive the hydraulic vane pump as the hydraulic source of the hydraulic circuit by the engine, and during operation, the engine runs at a low idling speed and reduces the centrifugal force of the vane 1d. In the method, all the systems of the hydraulic vane pump 1 according to the invention can be used.

[Brief description of the drawings]

1 is a system diagram showing a hydraulic control circuit for a clutch according to the present invention, FIG. 2 is a side sectional view of a hydraulic vane pump 1 used in FIG. 1, and FIG. 3 is a hydraulic vane pump according to the present invention. FIG. 4 is a flowchart showing a conventional hydraulic control circuit for a clutch by a system diagram. The reference numerals used in the examples are as follows. 1: Hydraulic vane pump, 1a: High hydraulic line, 1b: Cam ring,
1c: rotor, 1d: vane, 1e, 1f: groove, 1g, 1h: displacement chamber,
2: Hydraulic adjusting valve, 3: Switching valve, 4: Reservoir, 6: Back pressure valve, 7: Hydraulic actuator, 7a, 7b: Displacement chamber, 7d: Low hydraulic line.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F04C 2/30-2/352 F04C 15/04 311

Claims (2)

(57) [Claims] A hydraulic actuator (7) is provided with a low hydraulic line (7) acting in a direction of disengaging a clutch from an engine.
One displacement chamber conducting hydraulic pressure from d) (7b)
And a high hydraulic pressure line (1) acting in a direction to engage the clutch in opposition to the oil pressure in the one displacement chamber (7b).
a) the other displacement chamber (7a) for selectively guiding the hydraulic pressure, and the other displacement chamber (7a) is provided between the other displacement chamber (7a) and the high hydraulic pressure line (1a). A switching valve (3) for selectively communicating with the high hydraulic line (1a) or the reservoir (4), and between the low hydraulic line (7d) and the reservoir (4). Is provided with a back pressure valve (6) for setting the hydraulic pressure of the low hydraulic pressure line (7d) constant, and the high pressure line (1a) and the low hydraulic pressure line (7d) are provided between the high hydraulic pressure line (7d) and the low hydraulic pressure line (7d). A hydraulic adjustment valve (2) for controlling the hydraulic pressure of the hydraulic pipeline (1a) is provided. The hydraulic vane pump (1) is provided at a plurality of positions in a circumferential direction of a rotor (1c) driven by the engine, and A vane (1d) is inserted into each groove (1k) cut in each radial direction to enable sliding in that radial direction. Each vane (1d) is slidably in contact with the cam ring (1b), and each displacement chamber (1g, 1h) formed by the vane (1d), the rotor (1c) and the cam ring (1b). ), The displacement chamber (1g) on the suction side, which is performing an expansion stroke by the rotation, communicates with the reservoir (4) via the suction port, and the displacement chamber (1g) on the discharge side, which is performing the compression stroke by the rotation, 1h) communicates with the high hydraulic pipeline (1a) through a discharge port, and the radial direction of the vane (1d) forming the displacement chamber (1h) on the discharge side in the hydraulic vane pump (1). A hydraulic pressure from the high hydraulic pressure line (1a) after the engine is once increased to a predetermined rotational speed is led to a rear surface of the hydraulic vane pump (1) to displace the suction side displacement chamber (1g) in the hydraulic vane pump (1). The vane forming (1d) Wherein the back of the radial, once the engine, a variable displacement hydraulic vane pump which led to hydraulic pressure from the low pressure pipe after increased to a predetermined rotational speed (7d). 2. A rotor (1c) driven by an engine.
A plurality of vanes (1d) are slidably inserted in the grooves (1k) at a plurality of positions in the circumferential direction and cut in the respective radial directions at the plurality of positions. The tip of each vane (1d) is slidably in contact with the cam ring (1b), and each displacement chamber (1) formed by the vane (1d), the rotor (1c) and the cam ring (1b).
g, 1h), the displacement chamber (1g) on the suction side, which is performing the expansion stroke by the rotation, communicates with the reservoir (4) via the suction port, and the discharge side on the discharge side, which is performing the compression stroke by the rotation, The displacement chamber (1h) communicates with the high hydraulic pressure line (1a) through a discharge port, and the hydraulic pressure from the high hydraulic pressure line (1a) is used as a hydraulic pressure source in the radial direction of the vane (1d). In the hydraulic vane pump (1) led to the back, immediately after the start of the engine,
A method for driving a hydraulic vane pump, wherein the rotational speed of the engine is increased to a constant rotational speed for a predetermined time before the hydraulic oil of a) is used as hydraulic energy.