JPH06207581A - Vane type hydraulic motor - Google Patents

Abstract

PURPOSE:To improve precision of position control of the turret of a lathe by reliably preventing isolation of a vane from the slide contact surface of a cam ring and preventing the occurrence of runaway of a rotor. CONSTITUTION:A vane type hydraulic motor comprises a rotor 1 having a number of vanes 12; slide contact surfaces 21 and 25 with which the head part of the vane 12 is brought into contact; and a cam ring 12 having a liquid feed part 2 and a liquid discharge part 24. The vane type hydraulic motor is formed such that a press chamber 13 is arranged at the bottom part of a slit 11 in which the vane 1 is inserted and the vane 12 is pressed against the slide contact surfaces 21 and 25 by means of a liquid pressure guided to the press chamber 13. A constant ratio pressure reducing valve 4 to reduce a pressure on the liquid feed side at a specified rate by setting a specified ratio of a sum of a pressure on the liquid feed side and a pressure liquid discharge side as a pilot pressure is located in a press passage 3 communicated to the press chamber 13 for the vane 12 oh which the both pressures of the pressure on the liquid feed side and the pressure on the liquid discharge side are exerted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vane hydraulic motor used for automatic machine tools such as turret lathes and other machines.

[0002]

2. Description of the Related Art Conventionally, a vane type hydraulic motor is known as disclosed in, for example, Japanese Patent Application Laid-Open No. 58-82078. The vane type hydraulic motor disclosed in this publication is
As shown in FIG. 5, a large number of slits A extending radially.
1, a vane A2 is slidably inserted into each of these slits A1, and the head of the vane A2 is slidably contacted with the rotor A having an output shaft C coupled to the central portion and the inner peripheral surface. Sliding contact surface B1 that determines the stroke of A2 and liquid supply section B
2 and a cam ring B having a drain portion B3, and the vane A2 is provided on the bottom surface side of the slit A1.
A piston A3 that presses in the direction of is arranged, and the vane A2 is pressed against the sliding contact surface B1 of the cam ring B by applying hydraulic pressure to the back chamber A4 provided on the back side of the piston A3. It is a thing.

The above vane type hydraulic motor is provided with a hydraulic pump D, and the discharge side of the hydraulic pump D has a first valve E having a manually operated spool E1 and a spool. A second valve F having F1 is provided, the secondary side of the second valve F is communicated with the liquid supply part B2, and the primary side of the first valve E is communicated with the back chamber A4. There is.

At the start of operation of the vane type hydraulic motor, the first valve E is held in the open state by the manual operation of the spool E1, and the second valve F is also operated.
The spool F1 is always urged in the blocking direction by a spring to be held in the blocked state.

However, in order to operate with the above configuration, first, the hydraulic pump D is driven, and the driving of the hydraulic pump D causes the pressure liquid PP discharged from the pump D to be the above-mentioned. First and second discharge pipes E connected from the input port E2 of the first valve E to the discharge side of the first valve E
Although it tries to reach the side of the second valve F via 3, E4, since the second valve F is blocked at the start of operation, the pressure liquid PP from the hydraulic pump D enters the input port E2. The liquid is supplied from the connected liquid pipe E5 to the back chamber A4 of the rotor A, and the vane A2 is pressed against the sliding contact surface B1 of the cam ring B via the piston A3 by the hydraulic pressure acting on the back chamber A4. Contacted. Incidentally, on the body side where the rotor A and the cam ring B are assembled, a large number of discharge ports a for releasing the hydraulic pressure supplied to the rear chamber A4 provided in the rotor A to the outside are formed. Also,
Input port E2 of the hydraulic pump D and the first valve E
And a relief valve D1 for relieving the pressure liquid PP when the pressure liquid PP reaches a predetermined pressure or more.

Further, a communication pipe F3 having an orifice F2 in the middle is connected between the liquid pipe E5 and the second valve F, so that the pressure liquid P passing through the liquid pipe E5 is connected.
Part of P is connected to the second valve F via the communication pipe F3.
The spool F1 acts as a pilot pressure on the spool F1 and the spool F1 is moved to the left in the figure, and each passage of the second valve F is opened. Therefore,
The pressure liquids P1 and P2 discharged from the first and second discharge pipes E3 and E4 of the first valve E pass through the second valve F to supply the second valve F and the cam ring B respectively. The liquid is supplied to each of the liquid supply parts B2 via liquid supply pipes F4 and F5 provided between the liquid supply part B2 and the part B2, while each drainage part B3 of the cam ring B is connected to a tank via a drainage pipe E6. Since it is opened to the side, the vanes A2 are pressed to the right by the pressure liquids P1 and P2 supplied to the liquid supply parts B2, and the rotor A is moved to the right as shown by the arrow in the figure. The output shaft C coupled to the rotor A is driven to rotate in the same direction, and the position control of, for example, a turret in a lathe is performed via the output shaft 55.

Further, when the first valve E is held in the open state as shown in the figure, as described above, the first and second discharge pipes E3 and E4 of the first valve E are connected to the cam ring. The rotor A is rotated at a high speed by acting the pressure liquids P1 and P2 supplied to the liquid supply parts B2 on the vanes A2 because they are both connected to the liquid supply parts B2 of B. You can On the other hand, by manually operating the spool E1 provided on the first valve E,
When one of the second discharge pipes E3 and E4 is connected to the low pressure side and the other is connected to the high pressure side, only one of the pressure liquids P1 and P2 connected to the high pressure side is caused to act on the vane A2,
The rotor A can be rotated at a low speed.

[0008]

However, the conventional vane type hydraulic motor constructed as described above has the above-mentioned vane A2.
Since the liquid chamber E4 communicating with the discharge side of the hydraulic pump D is connected to the rear chamber A4 of the piston A3 provided on the bottom side of the vane, the discharge side pressure liquid is supplied. The pressing force that presses A2 against the sliding contact surface B1 of the cam ring B is constant corresponding to the pressure set by the relief valve D1. Therefore, the vane A2
The pressure on the liquid supply side and the pressure on the liquid discharge side acting on the head of the are constant pressure, the force (back pressure) for separating the vane A2 from the sliding contact surface B1 is constant, and the sliding contact When it is balanced with the pressing force pressing against the surface B1, it can be pressed against the sliding contact surface with a predetermined pressure balance, but when the back pressure acting on the vane head becomes large, For example, when the rotation of the rotor A is stopped by stopping the hydraulic pump D, and the rotor A pumps by its inertial rotation, the drainage portion B3 is generally used.
5 communicates with the tank T via the throttle (back pressure portion) G as shown in FIG. 5, the pressure of the drainage portion B3 increases, and the back pressure increases to increase the pressure. The balance is lost, the vanes A2 are separated from the sliding surface B1, the rotor A runs away, and there arises a problem that accurate position control cannot be performed.

On the other hand, the direction of the rotor A can be switched between forward and reverse by using a directional flow control valve instead of the first valve E and the second valve F, and an arbitrary speed control of the rotor A can be performed by the flow control. Also provided are those that enable position control. However, in order to improve the responsiveness of the directional flow control valve, the spool land wrap amount in the neutral state is usually used with zero wrap or under lap, and the discharge side pressure of the hydraulic pump is Since the pressure is controlled to be constant by the relief valve or the PC valve, the following problems occur in the vane type hydraulic motor using the above directional flow control valve.

That is, when the directional flow control valve is positioned in the neutral state and the liquid supply part and the liquid discharge part are blocked on the hydraulic pump and the tank side, the rotor rotates inertially to act as a pump. As in the above-mentioned conventional example, the pressure of the drainage portion, that is, the back pressure acting on the vane increases,
If the vane is released from the sliding surface of the cam ring and the rotor runs out of control, and the land up amount of the spool is zero lap or under lap, the directional flow control valve spoils. When the rotor is stopped by setting the valve to the neutral state, both the liquid supply side pressure and the liquid discharge side pressure rise, and the vanes are balanced when they are separated. There is also a problem that the rotor does not move even if it is tried to drive it.
In addition, when a brake is applied by a pump action to stop the turret connected to the output shaft of the rotor at a desired position, the liquid supply portion is charged to prevent it from becoming vacuum. Then, depending on this charging method, the pressure of the liquid supply part increases and the vanes are released, which causes a problem that the vane cannot be stopped at a desired position.

With respect to the above problems, it is conceivable to increase the pressing force of the vane A2 by increasing the diameter of the piston A3 in the structure of the conventional example described above.
In this case, there is a problem that the pressing force during steady operation becomes too large and the friction loss becomes large, or the frictional resistance becomes large and power loss occurs, and the above-mentioned problem cannot be fundamentally solved.

An object of the present invention is to prevent the vane from being separated from the sliding contact surface of the cam ring even if the back pressure acting on the head of the vane becomes high, and to accurately drive a driven member such as a turret in a lathe. While the position can be controlled, the pressing force to the sliding contact surface of the cam ring can be properly adjusted to reduce the friction loss, and the friction resistance can be reduced to improve the efficiency.

[0013]

In order to achieve the above-mentioned object, in the first invention, a large number of vanes 1 arranged radially are provided.
2. A rotor 1 having 2 and a sliding contact surface 2 on which the head of the vane 12 slidably contacts the inner peripheral surface thereof and which determines the stroke of the vane 12.
1, 25, a cam ring 2 having a liquid supply section 23 and a liquid discharge section 24, a press chamber 13 is provided at the bottom of a slit 11 into which the vane 1 is inserted, and the hydraulic pressure introduced to these press chambers 13 causes The vane 12 is attached to the sliding contact surfaces 21, 25 of the cam ring 2.
In the vane type hydraulic motor that is pressed against, the pressurizing passage 3 communicating with the pressurizing chamber 13 of the vane 12 of the pressurizing chamber 13 where both the pressure on the liquid supply side and the pressure on the liquid draining side act, The constant ratio pressure reducing valve 4 is provided to reduce the liquid supply side pressure at a constant rate with the constant ratio of the sum of the liquid supply side pressure and the drainage side pressure as the pilot pressure.

Further, in the above construction, the liquid supply section 2
3 and the drainage unit 24 are connected to the hydraulic pressure source 5 via the flow rate control valve 6, and the primary side pressure of the flow rate control valve 6 and the liquid supply side pressure are applied to the primary side of the constant ratio pressure reducing valve 4. A high pressure selecting means 7 for selecting a higher pressure of the secondary side pressure may be provided.

In the second aspect of the invention, the liquid supply section 23 and the drainage section 24 are communicated with the hydraulic pressure source 5 via the directional flow control valve 6 under the same preconditions as the first invention. Of the pressure chamber 13, the pressure chamber 13 of the vane 12 on which both the pressure on the liquid supply side and the pressure on the liquid discharge side act and the directional flow control valve 6
The pressing passage 3 is provided between the pressing passage 3 and the secondary side of
Further, the secondary-side high-pressure selecting means 8 for selecting a higher pressure of the liquid supply-side pressure and the liquid discharge-side pressure on the secondary side of the directional flow control valve 6 is provided.

[0016]

In the vane type hydraulic motor according to the first aspect of the present invention, the constant ratio pressure reducing valve 4 interposed in the pressing passage 3 causes a constant ratio to the sum of both the liquid supply side pressure and the liquid discharge side pressure. Is used as a pilot pressure to reduce the pressure on the liquid supply side at a constant rate, and the pressure reduced at this predetermined rate is applied to the pressing chamber 13 via the pressing passage 3 to move the vane 12 to the sliding contact surface of the cam ring 2. Since the pressure is applied to 21 and 25, no matter whether the pressure on the liquid supply side or the pressure on the liquid discharge side fluctuates,
The vane 12 is attached to the sliding contact surfaces 21, 25 of the cam ring 2.
It can be pressed with a predetermined pressing force without being released. That is, the liquid supply and drain parts 23, 2
Even if the liquid supply and drain pressures in 4 fluctuate and the back pressure increases, the pressure at a constant ratio to the sum of these two pressures,
Since it can be applied to the pressing chamber 13 of the vane 12, it is possible to press the vane 12 against the sliding contact surfaces 21 and 25 with a predetermined pressing force. Release to 21, 25 can be prevented. Therefore, even if a flow control valve with a spool land wrap amount of zero lap or under lap is used, the rotor 1 can be smoothly started when the operation is started from the state in which the spool lap amount is stopped at the neutral position.
Even when the rotor 1 is stopped by applying a brake by a pump action, the rotor 1 can be prevented from running away and accurate position control of the turret or the like on the lathe can be performed. Moreover, since the vane 12 is pressed against the sliding contact surfaces 21 and 25 by the pressure applied to the pressing chamber 13, the pressing force to the sliding contact surfaces 21 and 25 can be made appropriate, and the sliding contact can be performed. It is possible to reduce the friction loss of the surfaces 21, 25 and the head of the vane 12, reduce the frictional resistance, and improve the efficiency.

Further, in the above construction, the liquid supply section 2
3 and the drainage unit 24 are connected to the hydraulic pressure source 5 via the flow rate control valve 6, and the primary side pressure of the flow rate control valve 6 and the liquid supply side pressure are applied to the primary side of the constant ratio pressure reducing valve 4. When the high pressure selecting means 7 for selecting a high pressure among the secondary pressures is provided, the high pressure selecting means 7 selects a high pressure of the primary pressure and the secondary pressure, and the high pressure selecting means 7 selects the high pressure through the constant ratio pressure reducing valve 4. Since it is applied to the pressing chamber 13 by means of the pressurization chamber 13, it is possible to compensate at the start of operation and effectively eliminate the insufficient pressing force of the vane 12 even when a brake is applied by the pump operation, and the sliding contact of the vane 12 is prevented. It is possible to reliably prevent the release from the surfaces 21 and 25.

Further, the hydraulic pressure source 5 and the cam ring 2
Directional flow control valve 6 between the liquid supply and drain parts 23, 24 of
And a pressurizing passage 3 is provided between the secondary side of the directional flow control valve 6 and the pressurizing chamber 13, and the pressurizing passage 3 is connected to the liquid supplying and draining parts 23, 24 on the liquid supplying side. Since the secondary side high pressure selecting means 8 for selecting a higher pressure between the pressure and the drain side pressure is provided, the vane 12 can be operated in either forward or reverse direction by switching the directional flow control valve 6. The high pressure selecting means 8 while being able to rotate in any direction.
Selects the higher pressure of the liquid supply side and the liquid discharge side pressure discharged to the secondary side of the directional flow control valve 6, and presses the pressure chamber 1
It is possible to prevent release of the vane 12 with a simple structure by acting on 3 and even if a directional flow control valve with a spool land wrap amount of zero lap or under lap is used, the rotor 1 does not move at the start of operation. It can be started smoothly without being lost, and when the rotor 1 is stopped by applying a brake by a pump operation, the rotor 1 is prevented from running away and the lathe is turned off. The driven object such as the turret can be stopped at an accurate position and the accuracy of its position control can be improved.

[0019]

FIG. 4 shows an example in which the vane type hydraulic motor according to the present invention is applied to drive a turret in a lathe machine. The lathe apparatus shown in FIG. 4 rotatably supports a cylindrical shaft 33 in a housing 31 via a plurality of bearings 32, and a turret 34 to which a plurality of types of blades and the like are attached to one end of the shaft 33 in the axial direction. Bolt to 34a
And a vane type hydraulic motor 35 is disposed on one side of the housing 31 around the outer circumference of the shaft 33. The hydraulic motor 35 causes the turret 34 to move through the shaft 33 in a predetermined manner. It is designed to be angularly driven to the working position.

An end cover 36 having various passages, which will be described later, is provided on the outer periphery of the shaft 33 on the side opposite to the turret of the hydraulic motor 35.
The balance pressure generating means 100 and the directional flow control valve 6 which will be described later are attached to the outer periphery of the shaft 33 and
An angle detecting means 37 such as a rotary encoder is provided on the other end side of the, and an elastically deformable clamp sleeve 38 is provided between the housing 31 and the shaft 33.
And a high pressure is applied to the clamp sleeve 38 from a high pressure generating means 39 provided on the outer periphery of the housing 31 to elastically deform the clamp sleeve 38, thereby applying a brake to the shaft 33. Thus, the shaft 33 can be forcibly stopped.

As is apparent from FIG. 1, the vane type hydraulic motor 35 comprises a rotor 1 spline-coupled to the shaft 33 and a cam ring 2 arranged around the outer periphery of the rotor 1. The rotor 1 is provided with a large number of radially extending slits 11, and vanes 12 each having an anti-spherical shape on the tip head side are slidably inserted into the respective slits 11. Further, a head side of the vane 12 is in sliding contact with an inner peripheral surface side of the cam ring 2 facing the rotor 1, and has a sliding contact surface 21 that determines a stroke of the vane 12, and a plurality of the vanes 21 are projected. The arcuate concave portions 22 and the arcuate peripheral surface having the sliding contact surface 25 for retracting the vane 12 are formed between the concave concave portions 22.
A liquid supply part 23 and a liquid discharge part 24 are formed in the front and rear parts of the recessed part 22 defined by the vane 12 that is in sliding contact with the sliding contact surface 21. Further, a pressing chamber 13 is formed on the bottom side of each slit 11 provided in the rotor 1, and a spring 14 that abuts against the back side of the vane 12 is disposed in each pressing chamber 13, and A hydraulic pressure is introduced into each of the pressing chambers 13, and the tip end side of the vane 12 is pressed against the sliding contact surfaces 21 and 25 of the cam ring 2 by the hydraulic pressure and the spring 14. There is.

However, what is shown in FIG. 1 is the liquid supply side in the liquid supply part 23 formed in the cam ring 2 among the pressing chambers 13 provided on the rotor 1 side in the above vane type hydraulic motor 35. The pressure chamber 13 on which both the pressure and the pressure on the drain side of the drain portion 24 act, that is, the vane 1 slidingly contacting the intermediate portion of the sliding contact surface 21 and the sliding contact surface 25.
The pressure passage 3 communicating with the second pressure chamber 13 is provided with a constant ratio pressure reducing valve 4 for reducing the liquid supply side pressure at a constant rate with the constant ratio of the sum of the liquid supply side pressure and the drainage side pressure as the pilot pressure. It was.

The embodiment shown in FIG. 1 includes a hydraulic pump 51,
A hydraulic pressure source 5 including a motor 52 for rotating the pump 51 is provided, a directional flow control valve 6 is connected to the discharge side of the hydraulic pressure source 5, and the constant ratio pressure reducing valve 4 is provided in the pressing passage 3. Is provided.

More specifically, the directional flow control valve 6 will be described.
Is a 4-port 3-position proportional servo valve as symbolized in FIG. 1, in which the discharge line 53 of the pump 51 is connected to the pump port P and the tank port T is connected to
The back pressure valve 55 is connected to the tank T of the hydraulic pressure source 5,
A tank line 54 having a connection is connected to the two switching ports X and Y, and a liquid supply / drain pipe 6 serving as a liquid supply pipe or a liquid discharge pipe.
1, 62 are connected, and these supply / drainage pipes 61, 62
Branch pipes 61a and 62a, respectively, and branch pipes 61a and 62a of the valve plate 80, which are interposed between the supply / drain passages 36a and 36b provided in the end cover 36 and between the end cover 36 and the cam ring 2. The liquid supply unit 2 of the cam ring 2 via the communication passages 80a and 80b.
3 and the drainage unit 24.

In the configuration shown in FIG. 1, one of the supply / drainage pipes 61, 62 serves as a liquid supply pipe and the other serves as a drainage pipe by the switching operation of the directional flow control valve 6. When the drainage pipe 61 serves as a liquid supply pipe and the supply and drainage pipe 62 serves as a drainage pipe,
The pressure liquid from the discharge line 53 is supplied to the liquid supply part 23 communicating with the supply / drainage pipe 61, and the liquid discharge part 24 communicating with the supply / drainage pipe 62 is communicated with the tank line 54 to be discharged. On the other hand, when the liquid supply / drainage pipe 61 serves as a liquid drainage pipe and the liquid supply / drainage pipe 62 serves as liquid supply, the liquid supply part 23 communicates with the discharge line 53. In this case, since the flow control valve is used without using the directional flow control valve and the rotor 12 is rotated only in one direction, the communication side with the supply / drainage pipe 61 is referred to as the supply side portion 23 for convenience of description. The communication side with the supply / drainage pipe 62 is referred to as a drainage unit 2
It is called 4.

On the other hand, the end cover 36 is provided with a secondary passage 3a for connecting the secondary side of the constant ratio pressure reducing valve 4 in the pressing passage 3 in which the constant ratio pressure reducing valve 4 is interposed. The valve plate 80 includes the secondary passage 3a.
Are provided with a plurality of communication passages 3c communicating with a plurality of inlet ports 3b opening on the rotation locus of the pressing chamber 13 provided in the rotor 1. Further, the primary side of the constant ratio pressure reducing valve 4 in the pressing passage 3 is connected to the discharge line 53 of the hydraulic pump 51 in the hydraulic pressure source 5, but in the embodiment shown in FIG. The discharge line 53 and the pilot passages 63 and 64 which will be described later are provided through the selecting means 7.
It is connected to one of the pilot passages 63 or 64, which has a higher pressure.

Thus, when the rotor 1 rotates with respect to the cam ring 2, the pressing chambers 13 and the inlet port 3 are rotated.
When b matches, the pressure liquid supplied from the secondary side of the constant ratio pressure reducing valve 4 in the pressure passage 3 is supplied to each of the pressure chambers 13, and the pressure liquid supplied to these pressure chambers 13, The vane 12 is pressed against the sliding contact surface 21 of the cam ring 2 by the pressing force of the spring 14 arranged in each pressing chamber 13, and the vane 12 is pressed against the sliding contact surface 21. The cam ring 2 upon contact
The liquid supply part 23 and the liquid discharge part 24 are formed in a defined manner at the front and rear parts of the recessed part 22 provided in the. Further, a plurality of discharge ports 3d are formed near the inlet port 3b on the rotation loci of the pressing chambers 13 in the end cover 36 and the valve plate 80, and the rotor 1
When the pressing chambers 13 and the discharge port 3d are aligned with each other when rotating with respect to the cam ring 2, although not shown, the pressure liquid in the pressing chambers 13 is returned to the tank side.

The constant ratio pressure reducing valve 4 constitutes the balance pressure generating means 100, and as shown in FIG.
A first valve casing 40A and a second valve casing 40B, which are divided into two parts, are integrally provided with a valve body 40,
A three-land type first spool 45 is slidably installed in the valve chamber of the first valve casing 40A, and two lands 49 having different diameters are provided in the valve chamber of the second valve casing 40B.
A second land type second spool 49 having a and 49b is slidably installed, and a front end portion of the second spool 49 is opposed to a rear end portion of the first spool 45. Let The inlet port 41 communicating with the high pressure selection passage 77 of the high pressure selection means 7 described later is provided on the primary side of the first valve casing 40A.
And a tank port 42 for opening an interlocking portion where the first spool 45 and the second spool 49 face each other to the tank, and the pressing chamber of the pressing passage 3 is provided on the secondary side. Side (secondary side) is provided with an outlet port 43, and the outlet port 43 is provided in a front chamber 44a of the first spool 45 formed by screwing a plug 4C to the first valve casing 40A. A communication passage 44 communicating with each other is provided, and by the intermediate land 45a in the first spool 45,
The pressure liquid supplied to the high pressure selection passage 77 is depressurized at a constant depressurization ratio based on the opening degree of the intermediate land 45a with respect to the inlet port 41, and the depressurized pressure liquid is supplied to the secondary side of the pressing passage 3. I am trying to guide you.

Further, in the second valve casing 40B,
Between the lands 49a and 49b of the second spool 49, a supply / drainage pipe 61 connected to the secondary side of the directional flow control valve 6,
A first inlet port 46 for communicating one of the pilot passages 63 and 64 branched from the middle of 62 is provided, and the other pilot passage 64 is connected to the rear chamber of the second spool 49. A second inlet port 47 is provided to allow the plug 4D to be screwed to the rear end of the second spool 49 and the second valve casing 40B.
A spring 50 is interposed between and.

In the embodiment shown in FIG. 2, the second
The pressure receiving area ratio of the lands 49a and 49b in the spool 49 is set to 2: 1, and the pressure of the supply / drainage pipes 61 and 62 acting via the pilot passages 63 and 64 causes the second spool 49 The pressing force to the 1-spool 45 is set to be 1: 1. That is, the supply / drainage pipe 6
50% of the sum of the liquid supply side pressure acting on one side and the drainage side pressure acting on the other side is made to act on the first spool 45 via the second spool 49 as a pilot pressure. The pressure in the high pressure selection passage 77, in other words, the pressure on the liquid supply side can be reduced at a constant rate. The pilot pressure is 50, which is the sum of the liquid supply side pressure and the liquid discharge side pressure.
It is not necessary to set to%, and the ratio may be increased.

Next, the operation of the embodiment configured as described above will be described. First, when the rotor 1 is rotationally driven in the right direction shown by the arrow in FIG. 1, the directional flow control valve 6 is switched to the left position in FIG. 1, and the supply / drainage pipe 61 is used as a supply pipe. In addition to communicating with the discharge line 53, the supply / drainage pipe 62 is communicated with the tank line 54 as a drainage pipe. Therefore, the pressure liquid in the discharge line 53 is supplied to the cam ring 2 via the supply / drainage pipe 61.
Of the pressure liquid P1 supplied to the liquid supply unit 23, the vane 12 is pressed to the right by the pressure liquid P1 supplied to the liquid supply unit 23. ,
Since the tank is opened from the water supply / drainage pipe 62 to the tank side, the rotor 1 is rotated in the right direction, and the shaft 33 coupled to the rotor 1 is rotationally driven in the same direction, so that the turret provided on the lathe. The position control of 34 is performed.
Contrary to the case described above, when the pressure liquid is supplied and discharged in the opposite direction by the switching operation of the directional flow control valve 6, the rotor 1 is rotationally driven in the left direction.

When the rotor 1 is driven to rotate as described above, the inlet port 41 of the first valve casing 40A.
To the second side from the pilot passages 63 and 64 connected to the secondary side of the directional flow control valve 6 and into which the higher pressure fluid is introduced from the discharge line 53 and the supply / drainage pipe 61. The first and second inlet ports 46 of the valve casing 40B,
The pressure liquid having the liquid supply side pressure and the discharge liquid having the liquid discharge side pressure are introduced into 47, respectively, and a fixed ratio (50%) to the sum of both the liquid supply side pressure and the liquid discharge side pressure is the pilot pressure. Acting on the second spool 49 and pushing the first spool 45 through the second spool 49, the land 45a of the first spool 45 reduces the pressure liquid at a constant rate, and thus the pressure is reduced. The pressure liquid is the pressure passage 3
Is introduced into the pressing chamber 13 of the rotor 1 from the above, and the pressing force by the pressure reduced as described above and the spring 14
The vane 12 is pressed against the sliding contact surfaces 21 and 25 by the pressing force of.

Therefore, even if the pressure on the liquid supply side or the pressure on the liquid discharge side may be higher than the pressure in the discharge line 53, the vane 12 can be prevented from being separated from the sliding contact surfaces 21 and 25 of the cam ring 2. . That is, the directional flow control valve 6
When the brakes are applied to the rotor 1 by pumping the supply / drainage pipes 61 and 62 in the neutral position, the pressure of the drainage part 24 is changed to the pressure of the discharge line 53 by the inertial rotation of the rotor 1. Will increase more, and also
In the case of pumping as described above, in order to prevent the liquid supply unit 23 side from becoming vacuum, the liquid supply unit 2
When the charging is performed on the third side, the pressure on the liquid supply unit 23 side becomes higher than the pressure on the discharge line 53 depending on this charging method, but in either case, the sum of the liquid supply side pressure and the drainage side pressure is the sum. Is used as a pilot pressure, and the pressure obtained by depressurizing the liquid supply side pressure at a constant rate is applied to the pressing chamber 13 of the vane 12 to press it.
When the back pressure acting on the head of No. 2 increases, the pressing force that presses the vane 12 against the sliding contact surfaces 21 and 25 also increases and balances.
Can be prevented from being separated from the sliding contact surface 21. As a result, when the rotor 1 is braked by the pump action, it is possible to prevent the vane 12 from separating and the inertial rotation from running out of control, so that the rotor 1, and thus the turret, are stopped at a desired position, and the position control is performed. The accuracy can be improved.

Further, when the spool land lap amount at the neutral position of the directional flow control valve 6 is zero lap or underlap, the liquid supply section 23 is in the neutral state.
And the pressure of the drainage unit 24 will both increase,
Even in this case, the pressurizing chamber 13 of the vane 12 is acted on by a constant pressure of the sum of the liquid supply side pressure and the liquid discharge side pressure in the neutral state as the pilot pressure. Therefore, the vane 12 is pressed against the sliding contact surfaces 21 and 25 without being released, and the problem that the rotor 1 does not move at the time of restart can be avoided.

As described above, in any case, the vane 12
Since it is possible to prevent the back pressure acting on the head of the vehicle from increasing and losing the balance to release the vane 12, it is possible to avoid the braking method by the pump action of the rotor 1, the configuration of the directional flow control valve 6, and the drain side. A back pressure valve, a discharge line 53 and a relief valve or a PC valve can be freely selected, and there are no restrictions on the liquid supply pattern, so the application restrictions of the hydraulic motor can be reduced and versatility is improved. In addition, the position control of the rotor 1, that is, the position control of a driven object such as a turret driven by the rotor 1 can be accurately performed.

In addition, since the above-mentioned depressurizing pressure is applied to the pressing chamber 13, it is possible to set a balanced state close to a perfect balance. Therefore, friction loss is reduced and wear of the vane 12 and the cam ring 2 is reduced. Can decrease
It is also possible to reduce frictional resistance and efficiency.

In the embodiment shown in FIG. 1, the primary side pressure of the directional flow control valve 6, that is, the discharge pressure of the discharge line 53 and the liquid supply side pressure are provided on the primary side of the constant ratio pressure reducing valve 4. A high-pressure selecting means 7 is provided for selecting a higher pressure from the secondary side pressure of the directional flow control valve 6, that is, one of the supply / drainage pipes 61 and 62 on the high pressure side. . The high pressure selecting means 7 shown in FIG. 1 is provided with a shuttle valve 71 for selecting the high pressure side of the pilot passages 63, 64 branched from the supply / drainage pipes 61, 62, and at the same time, of the constant ratio pressure reducing valve 4. A secondary side passage 74 of the shuttle valve 71 is connected to the high pressure selection passage 77 connected to the inlet port 41 via a check valve 75, and a primary side of the pressure passage 3 connected to the discharge line 53. Is connected via a check valve 76. First, the shuttle valve 71 selects the high pressure side of the pilot passages 63 and 64, and then the high pressure side pilot passage 63 is selected.
Or, the high pressure side is selected from the pressure of 64 and the pressure of the discharge line 53, that is, the liquid supply side which becomes the high pressure of the primary side pressure and the secondary side pressure of the directional flow control valve 6 A pressure is selected, and the liquid supply side pressure is reduced by the constant ratio pressure reducing valve 4 at a constant rate.

Therefore, by using the above-mentioned high pressure selecting means 7, even if the secondary side pressure of the directional flow control valve 6 does not immediately rise at the start of operation, the vane 12 can be selected by selecting the pressure of the discharge line 53. Since the rising of the pressing chamber 13 of the rotor 1 can be accelerated, the pressing of the vane 12 at the start of operation can be compensated, and the rotor 1 can be operated by the pump action.
In the case of applying the brake, it is possible to compensate for the insufficient pressing force of the vane 12.

Next, the embodiment shown in FIG. 3 will be described. FIG. 3 shows an embodiment of the second invention, which is a secondary chamber of the pressing chamber 13 of the vane 12 and the directional flow control valve 6 on which both the pressure on the liquid supply side and the pressure on the liquid discharge side act. The pressure chamber 3 is provided between the pressure chamber 13 and the pressure chamber 13. The pressure chamber 3 is provided with a pressure passage 3 and a pressure higher than the liquid supply side pressure and the liquid discharge side pressure on the secondary side of the directional flow control valve 6 is selected. The secondary-side high-voltage selecting means 8 that communicates with is provided. That is, the secondary side high pressure selecting means 8 mainly uses the shuttle valve 81, and the supply / drainage pipe 61 connected to the secondary side of the directional flow control valve 6 is connected to the primary side of the shuttle valve 81. , 62 branching from the valve 62, 62, and the pressurizing passage 3 communicating with the pressurizing chamber 13 of the rotor 1 is connected to the secondary side of the shuttle valve 81.

As described above, the directional flow rate control is performed in the same manner as in the above-described first embodiment by causing the pressurizing chamber 13 to act on the high pressure side liquid supply side pressure of the secondary side of the directional flow control valve 6. The valve 6 is controlled to the neutral position to control the supply / drain pipes 61, 62.
When the rotor 1 is braked by a pumping action with the rotor blocked, the drainage portion 2 is rotated by inertial rotation of the rotor 1.
Even if the pressure of 4 increases, it is possible to prevent the vane 12 from separating from the sliding contact surfaces 21 and 25, and
Even if the spool land wrap amount is zero lap or under lap in the neutral state of the directional flow control valve 6, the vane 12 can be prevented from being released, and the vane release phenomenon as in the conventional example can be eliminated, and The same operation and effect as those of the first embodiment can be obtained with a simple structure such as the shuttle valve 81. Moreover, since the structure is simple, the degree of failure can be reduced, and malfunctioning due to dust can be reduced, and the cost is low. You can do it.

In the second embodiment, the vane release phenomenon can be avoided as in the first embodiment, and when the pressure on the liquid supply side is high, the pressing force of the vane 12 is also high, so that wear is reduced, Although the action and effect of the first embodiment which can reduce the frictional resistance cannot be obtained, the action and effect of avoiding the vane release phenomenon can be obtained. Therefore, when the pressure on the liquid supply side is low, it is improved as compared with the conventional example. You can expect the effect that was done.
When the pressure on the liquid supply side is high, the shuttle valve 8
The secondary side of No. 1 and the constant ratio pressure reducing valve shown in the first embodiment may be arranged.

[0042]

As described above, according to the present invention, the stroke of the vane 12 is determined by the rotor 1 having a large number of vanes 12 arranged radially and the head of the vane 12 slidingly contacting the inner peripheral surface thereof. The vane 1 is provided with a cam ring 2 having sliding contact surfaces 21, 25, a liquid supply portion 23, and a liquid discharge portion 24.
In the vane type hydraulic motor, a pressing chamber 13 is provided at the bottom of the slit 11 for inserting the vane, and the vane 12 is pressed against the sliding contact surfaces 21 and 25 of the cam ring 2 by the hydraulic pressure introduced into the pressing chamber 13. In the pressing chamber 13, the sum of the liquid supply side pressure and the liquid discharge side pressure is applied to the pressing passage 3 communicating with the pressure chamber 13 of the vane 12 on which both the liquid supply side pressure and the liquid discharge side pressure act. Since the constant ratio pressure reducing valve 4 for reducing the liquid supply side pressure at a constant ratio is provided by using the constant ratio of the above as the pilot pressure, even if either the liquid supply side pressure or the liquid discharge side pressure fluctuates,
The vane 12 can be constantly held in a pressed state with a predetermined pressing force without being separated from the sliding contact surfaces 21 and 25. As a result, even when the rotor 12 is braked by the pump action, the rotor 12 does not run away, so that the position of the driven object such as the turret can be accurately controlled, and the spool land lap amount can be reduced. Even if a zero-lap or under-rabb flow control valve is used, the problem that the rotor 12 does not move at the start of operation can be solved, and the pressing force to the sliding contact surfaces 21 and 25 of the vane 12 can be properly adjusted. 12 and sliding surface 2
The friction loss of Nos. 1 and 25 can be reduced, wear can be reduced, frictional resistance can be reduced, and efficiency can be improved.

Further, in the above structure, the liquid supply section 2
3 and the drainage unit 24 are connected to the hydraulic pressure source 5 via the flow rate control valve 6, and the primary side pressure of the flow rate control valve 6 and the liquid supply side pressure are applied to the primary side of the constant ratio pressure reducing valve 4. By providing a high pressure selecting means 7 for selecting a high pressure among the secondary pressures, the high pressure selecting means 7 selects the higher pressure of the primary pressure and the secondary pressure to select the constant ratio pressure reducing valve. Since it is made to act on the pressing chamber 13 via 4, it is possible to compensate at the time of starting the operation and to effectively eliminate the insufficient pressing force of the vane 12 even when the brake is applied by the pump operation. It is possible to reliably prevent the release of 12 from the sliding contact surfaces 21 and 25.

Further, the liquid supply unit 23 and the liquid discharge unit 24 are communicated with the hydraulic pressure source 5 via the directional flow control valve 6, and the liquid supply side pressure and the liquid discharge side pressure in the pressing chamber 13 are adjusted. The pressure passage 3 is provided between the pressure chamber 13 of the vane 12 on which both the pressures of the pressure acting on the pressure chamber 13 and the secondary side of the directional flow control valve 6 are provided.
In the case where the secondary side high pressure selecting means 8 which selects and communicates with the higher pressure of the liquid supply side pressure and the liquid discharge side pressure on the secondary side of the directional flow control valve 6 is provided, the vane has a simple configuration. Since the release of 12 can be prevented, even if a directional flow control valve with a spool land wrap amount of zero wrap or under lap is used, the rotor 1 can be smoothly started without stopping at the start of operation. Also, when the rotor 1 is stopped by applying a brake by the pump operation, the runaway of the rotor 1 is eliminated, and the driven object such as the turret on the lathe can be stopped at an accurate position. The control accuracy can also be improved.

[Brief description of drawings]

FIG. 1 is a piping diagram showing a vane hydraulic motor of a first invention.

FIG. 2 is a vertical sectional view showing a constant ratio pressure reducing valve.

FIG. 3 is a piping diagram showing a vane type hydraulic motor of a second invention.

FIG. 4 is a cross-sectional view of a main part of a lathe shown as an application example of the vane hydraulic motor.

FIG. 5 is a piping diagram showing a conventional vane type hydraulic motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotor 11 slit 12 vane 13 pressing chamber 2 cam ring 21,25 sliding contact surface 23 liquid supply part 24 draining part 3 pressing passage 4 constant ratio pressure reducing valve 5 hydraulic pressure source 6 directional flow control valve 7 high pressure selecting means 8 secondary side High voltage selection means

Claims (3)

[Claims] 1. A number of vanes (12) arranged radially.
With a rotor (1) having an inner peripheral surface, the head of the vane (12) slidingly contacts the inner peripheral surface, and the sliding contact surfaces (21) (25) and the liquid supply section (23) that determine the stroke of the vane (12). And a cam ring (2) having a drainage part (24), a pressing chamber (13) is provided at the bottom of a slit (11) into which the vane (12) is inserted, and the liquid is introduced into these pressing chambers (13). The vane (12) is pressed against the sliding surface (2) of the cam ring (2).
1) In the vane type hydraulic motor which is pressed against (25), of the pressing chamber (13), the pressing chamber of the vane (12) on which both the pressure on the liquid supply side and the pressure on the liquid discharge side act A constant ratio pressure reducing valve (4) for reducing the liquid supply side pressure at a constant rate using a constant ratio of the sum of the liquid supply side pressure and the liquid discharge side pressure as a pilot pressure in a pressing passageway (3) communicating with (13). A vane-type hydraulic motor characterized by being provided with. 2. The liquid supply part (23) and the liquid discharge part (24) are
It is connected to the hydraulic pressure source (5) through the flow rate control valve (6), and the primary side pressure and the liquid supply side pressure of the flow rate control valve (6) are connected to the primary side of the constant ratio pressure reducing valve (4). The vane type hydraulic motor according to claim 1, further comprising high-pressure selecting means (7) for selecting a higher pressure among the secondary pressures. 3. A number of vanes (12) arranged radially.
With a rotor (1) having an inner peripheral surface, the head of the vane (12) slidingly contacts the inner peripheral surface, and the sliding contact surfaces (21) (25) and the liquid supply section (23) that determine the stroke of the vane (12). And a cam ring (2) having a drainage part (24), a pressing chamber (13) is provided at the bottom of a slit (11) into which the vane (12) is inserted, and the liquid is introduced into these pressing chambers (13). The vane (12) is pressed against the sliding surface (2) of the cam ring (2).
1) In the vane type hydraulic motor which is pressed against (25), the liquid supply part (23) and the liquid discharge part (24) are connected to the hydraulic pressure source (5) via the directional flow control valve (6). The pressure chamber (1) of the vane (12), which is in communication with the pressure chamber (13) and on which both the pressure on the liquid supply side and the pressure on the liquid discharge side act.
3) is provided between the directional flow control valve (6) and the secondary side of the directional flow control valve (6), and the pressurizing passage (3) is provided on the secondary side of the directional flow control valve (6). Secondary-side high-pressure selecting means (8) for selecting a higher pressure between the pressure and the drain-side pressure
A vane-type hydraulic motor characterized by being provided with.