JP3883109B2 - Double-rotation vane pump device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention includes a casing, a vane pump main body housed in the casing, a first port provided in the casing and leading to a first suction port of the vane pump main body, and a first port of the vane pump main body provided in the casing. The present invention relates to a bi-rotary vane pump device provided with a second port that communicates with two suction ports.
[0002]
[Prior art]
Conventionally, in a double-rotation vane pump capable of both forward rotation and reverse rotation, a conduit with a double check valve including a pilot check that bypasses the vane pump is used to avoid cavitation damage that normally occurs during reverse rotation with negative suction pressure. In addition, measures such as providing a relief valve in a pipeline that generates suction negative pressure have been taken.
[0003]
However, due to the generation of negative pressure due to the delay in operation of the double check valve, complete avoidance of cavitation was inevitable. In addition, the installation of the pipe with the double check valve including the pilot check and the installation of the relief valve to the negative pressure generating pipe have the disadvantages of securing the installation and construction space and the complexity of the construction.
[0004]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a double-rotation vane pump device that does not have cavitation even if a pipe line with a double check valve including a pilot check is provided or a relief valve is not provided outside.
[0005]
[Means for Solving the Problems]
The double-rotary vane pump device of the present invention includes a casing, a vane pump main body housed in the casing, a first port provided in the casing and leading to a first suction port of the vane pump, and the casing. A second port communicating with the second suction port of the vane pump, a pressure regulating hole communicating with the first and second ports, and the pressure of the second port in the pressure regulating hole is a first predetermined pressure. And a second relief valve for adjusting the pressure of the second port to a second predetermined pressure in the pressure adjusting hole.
[0006]
Accordingly, if the first port to which positive pressure is applied is normally set to the suction side and the second port is set to the discharge side to perform forward rotation, the pressure in the second port on the discharge side becomes the first predetermined pressure ( For example, when the maximum allowable pressure is reached, the first relief valve adjusts the first predetermined pressure (the maximum allowable pressure) to prevent leakage due to overpressure and damage to the apparatus. When the reverse rotation operation is performed with the second port set as the suction side and the first port set as the discharge side, the pressure in the second port on the suction side is set to a second predetermined pressure (for example, allowable negative pressure). When the pressure reaches the value, the pressure is adjusted to the second predetermined pressure (allowable negative pressure) by the second relief valve, and damage to the vane body due to the occurrence of cavitation can be prevented.
[0007]
Moreover, according to the present invention, since the first and second relief valves are provided in the vane pump device of the present invention, a double check valve including a pilot check for a load device such as a fluid cylinder which has been conventionally performed. It can be easily attached to an existing load device without attaching an additional pipe line or attaching a relief valve to the external pipe line.
[0008]
The first relief valve is formed in the pressure adjusting hole, a cylindrical plunger slidably fitted in the pressure adjusting hole, an outer valve seat formed at one end of the plunger, and the pressure adjusting hole. The second relief valve is formed on the poppet valve disposed at the other end of the plunger, and the poppet valve is configured by a first spring that elastically supports the plunger in the axial direction. The outer valve seat, the inner valve seat formed on the plunger, and a second spring that elastically supports the poppet valve in the axial direction are preferable.
[0009]
In a specific implementation of the present invention, the first valve portion formed by the outer valve seat formed at one end of the plunger and the inner valve seat formed in the pressure adjusting hole has a first predetermined pressure. The first spring is pre-compressed so as to open at the maximum allowable pressure, and is composed of an outer valve seat formed on the poppet valve and an inner valve seat formed on the plunger. It is important that the second spring is pre-tensioned so that the second valve portion opens at a second predetermined pressure (allowable negative pressure).
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows an overall configuration cross section of a vane pump device 1 of the present invention. A vane pump main body 2 </ b> V whose details are shown in FIG. 3 is mounted on a casing 20 that includes the entire vane pump device 1.
[0011]
In the vane pump main body 2V, the liquid sucked from the first suction port 12 during the forward rotation by the four vanes 8 provided on the rotor shaft 6 driven by the drive shaft 5 and sliding in the radial direction is the liner ring 10 and the vane. This is a known vane pump that constitutes a positive displacement pump that moves through a gap 9 between 8 and pumps and pressurizes and discharges from a second suction port 14.
[0012]
In the figure, reference numerals 4 and 2 denote front and rear bearings for supporting the vane 8 and the liner ring 10 from the side. Further, the first and second suction ports 12 and 14 are formed in the front and rear bearings 4 and 2, respectively, and the vanes 8 slide in the radial direction by the check valves 16 and 18. Further, the check valve 16 or 18 acts as a check valve for the discharge side by forward rotation and reverse rotation. This operation is also known.
[0013]
Returning to FIG. 1, a first port Pa of the flow passage leading to the first suction port 12 of the vane pump body 2 </ b> V is provided in the casing 20, and a second port of the flow passage leading to the second suction port 14 of the vane pump body 2 </ b> V. Pb is provided in the casing 20. The first port Pa is in communication with a liquid tank that is normally guided at a positive pressure, and the second port Pb is in communication with a load device such as a hydraulic cylinder that accompanies the generation of a negative pressure.
[0014]
The casing 20 is provided with a pressure regulating hole 22 that communicates the first port Pa and the second port Pb, and a first relief valve Rv1 that regulates the pressure of the second port Pb in the pressure regulating hole 22; A second relief valve Rv2 is mounted.
[0015]
FIG. 2 shows details of the first and second relief valves Rv1 and Rv2 in FIG.
A plunger 26 having an outer diameter portion 26a formed in a fluid-tight and slidable manner is fitted in the pressure adjusting hole 22. The plunger 26 is formed in a cylindrical shape having an inner diameter portion 26 b, and a large diameter portion 26 c that is tapered from the outer diameter portion 26 a to the first port Pa side at one end thereof is formed. An outer valve seat 26e is formed in the tapered portion, an inner valve seat 22a is formed in the casing 20 corresponding to the outer valve seat 26e, and the first valve portion V1 is configured by the valve seats 26e and 22a. Yes.
[0016]
A groove 26o is formed in the outer diameter portion 26a of the plunger 26 so as to communicate with the second port Pb and reach the small diameter end of the outer valve seat 26e.
A hole 26f having a larger diameter than the inner diameter portion 26b is formed on the first port Pa side of the plunger 26, and the inner diameter portion 26b and the larger diameter hole 26f are connected by a shoulder portion 26d.
[0017]
A first spring 30 seated at one end of the shoulder 26d and elastically supporting the plunger 26 is accommodated in the hole 26f, and is disposed across the first port Pa coaxially with the pressure adjusting hole 22. The other end is seated and attached to the end of the pressure adjusting screw 32 screwed from the outside of the casing 20 so as to surround the positioning convex portion 32.
[0018]
The first spring 30 is mounted with a precompression force applied by a pressure adjusting screw 32. The precompression force is such that when the positive pressure in the second port Pb reaches the first predetermined maximum allowable pressure, the plunger 26 slides toward the first port Pa, and the outer valve seat 26e floats. It is set to do.
The pressure adjusting screw 32 is fixed and covered with a cap nut 34.
A first relief valve Rv <b> 1 is configured including the first spring 30, the first valve portion V <b> 1 including the valve seats 26 e and 22 a, and the plunger 26.
[0019]
A tapered inner valve seat 26h is formed on the second port Pb side of the other end of the plunger 26, and a poppet valve 24 in which a tapered outer valve seat 34a is formed is disposed. The valve seats 34a and 26h constitute a second valve portion V2.
[0020]
A stopper hole 24c is formed in the stem part 24b of the poppet valve 24, and a hook-like stopper part 28a at one end of the second spring 28 that elastically supports the poppet valve 24 is engaged with the stopper hole 24c.
An annular claw portion 28b having an enlarged diameter at the other end of the second spring 28 is locked so as to be seated on a shoulder portion 26d of the plunger 26, and a predetermined pretension is applied to the second spring 28 to thereby move the plunger 26. It is installed inside.
[0021]
The pre-tension is applied to the second spring 28 when the poppet valve 24 moves to the second port Pb side when the negative pressure in the second port Pb reaches the second predetermined allowable negative pressure. The outer valve seat 26h is set to float.
A second relief valve Rv2 is configured to include the second valve portion V2 configured by the first spring 28, the valve seats 34a and 26h, and the poppet valve 24.
[0022]
The operation of the vane pump device 1 having the above-described configuration will be described by taking the cylinder operation shown in FIG. 4 as an example.
A liquid tank that stores hydraulic fluid in the first port Pa of the vane pump device 1 constituted by the vane pump main body 2V, the first relief valve Rv1 and the second relief valve Rv2 shown individually in the drawing. Tc is communicated with the pipe line Lt, and the cylinder Cy that performs work with the hydraulic fluid is communicated with the second port Pb of the vane pump device 1 through the pipe line Lc.
[0023]
The first suction port 12 of the vane pump body 2V is in communication with the first port Pa, and the second suction port 14 is in communication with the second port Pb.
A cylinder rod Ps is slidably mounted in the cylinder Cy, and is configured to work outside by means not shown by the movement of the cylinder rod Ps by the hydraulic pressure applied to the lower surface of the cylinder rod Ps.
[0024]
In FIG. 1, when the vane 8 rotates forward in the R direction, the hydraulic fluid is guided from the liquid tank Tc to the first port Pa. The hydraulic fluid is further pressurized by the vane 8 from the first suction port 12 through the gap 9 and is pumped from the second suction port 14 to the second port Pb. The hydraulic fluid pumped to the second port Pb moves the cylinder rod Ps toward the top Cyu of the cylinder Cy via the pipe line Lc.
[0025]
When the cylinder rod Ps reaches near the cylinder top Cyu and the pressure of the hydraulic fluid pumped from the vane pump body 2V reaches the first predetermined maximum allowable pressure Pmax, the plunger 26 shown in FIGS. The first spring 30 of the first relief valve Rv1 is compressed and moved to the first port Pa side, the outer valve seat 26e floats, and the first valve portion V1 opens. By opening the valve, the groove 26o provided in the plunger 26 is communicated from the second port Pb to the first port Pa, and the hydraulic pressure in the second port Pb is reduced and adjusted to avoid overpressure. .
[0026]
Next, in order to move the cylinder rod Ps toward the cylinder bottom Cyd, when the vane pump main body 2V in FIG. 1 rotates backward in the L direction, the hydraulic fluid moves in the direction opposite to the movement of the hydraulic fluid in the forward rotation. . When the moving speed of the cylinder rod Ps is increased, a negative pressure is generated in the pipe line Lc and the second port Pb, and when the negative pressure reaches a predetermined limit allowable negative pressure Pmin, the poppet valve 24 is moved to the second spring. 28 is extended and moved to the second port Pb side, the outer valve seat 24a is floated, and the second valve portion V2 is opened.
[0027]
By opening the valve, the inner diameter portion 26b of the plunger 26 is communicated from the first port Pa to the second port Pb, and the hydraulic pressure in the second port Pb is adjusted to increase, thereby avoiding negative pressure that causes cavitation. Is done. And generation | occurrence | production of the noise by cavitation and damage to the vane pump main body 2V can be prevented.
[0028]
FIG. 5 is a block configuration diagram showing an example of use of a conventional double-rotary vane pump for explaining the effect of the vane pump device 1 of the present invention in comparison. Description will be made by omitting a self-evident part from the above description of FIG.
A liquid tank Tc for storing hydraulic fluid is connected to a first port Pa1 of a vane pump device Vr configured by a vane pump body 2V1 and a relief valve Vri that opens at an allowable maximum pressure Pmax through a pipe line Lt1. A cylinder Cy working with hydraulic fluid is communicated with the second port Pb1 of the vane pump device Vr through a pipe line Lc1.
[0029]
An external relief valve Vro is mounted between the pipe line Lt1 and the pipe line Lc1 to keep the negative pressure in the pipe line Lc1 at the limit allowable negative pressure Pmin.
Between the bottom of the cylinder Cy and the liquid tank Tc, a pipe line Cp with a pilot valve vp and a check valve vc is attached.
[0030]
With the above configuration, when the vane pump body 2V1 rotates forward, the relief valve Vri adjusts the overpressure applied to the cylinder Cy, and when the vane pump body 2V1 rotates backward, the pipe Cp that is interposed between the pilot valve vp and the check valve vc is externally attached. The over-negative pressure is reduced and adjusted by the relief valve Vro to avoid the occurrence of cavitation.
[0031]
In the conventional configuration shown in FIG. 5, if the vane pump device 1 of the present invention is used, the pipe line Cp and the external relief valve Vro interposing the pilot valve vp and the check valve vc can be reduced, thereby saving space and saving. Construction can be planned.
[0032]
【The invention's effect】
The effects of the present invention are listed below.
(1) In the vane pump device of the present invention, the first and second relief valves are built in, and cavitation does not occur even during reverse rotation. Therefore, the first port is connected to the liquid tank, and the second port is connected to the hydraulic cylinder. This will prevent cavitation damage.
(2) With the vane pump device of the present invention, it is possible to reduce the number of pipes and external relief valves that are conventionally provided with a pilot valve and a check valve, and space and construction can be saved.
(3) Since the first relief valve and the second relief valve are provided in the pressure adjusting hole, the structure is simple, the number of parts is small, and the assembly to the casing is easy without taking up space.
[Brief description of the drawings]
FIG. 1 is a structural cross-sectional view showing an embodiment of a double rotary vane pump device of the present invention.
FIG. 2 is an enlarged view showing details of the second and first relief valves of FIG. 1;
FIG. 3 is a structural sectional view of a vane pump main body.
FIG. 4 is a block configuration diagram showing an example of use of the dual rotary vane pump device of the present invention.
FIG. 5 is a block diagram showing a usage example of a conventional double-rotary vane pump.
[Explanation of symbols]
Pa ... first port Pb ... second port 1 ... vane pump device 2V ... vane pump body 6 ... rotor shaft 8 ... vane 10 ... liner ring 20 ... ··· Casing 22 ··· Pressure regulating hole Rv2 · · · Second relief valve 24 · · · Poppet valve 26 · · · Plunger 28 · · · Second spring Rv1 · · · First relief valve 30 · · · 1 spring 32 ... pressure adjusting screw

Claims (2)

A casing, a vane pump body housed in the casing, a first port provided in the casing and leading to a first suction port of the vane pump body, and a second suction port of the vane pump body provided in the casing. In the double-rotary vane pump device provided with a second port that communicates, a pressure adjusting hole that communicates the first and second ports, and the pressure of the second port in the pressure adjusting hole is a first predetermined value. A first relief valve for adjusting the pressure of the second port and a second relief valve for adjusting the pressure of the second port to a second predetermined pressure in the pressure adjusting hole. Rotary vane pump device. The first relief valve includes a cylindrical plunger slidably inserted into the pressure adjusting hole, an outer valve seat formed at one end of the plunger, and an inner valve formed in the pressure adjusting hole. A valve seat and a first spring that elastically supports the plunger in the axial direction. The second relief valve is a poppet valve disposed at the other end of the plunger, and an outer formed on the poppet valve. The double-rotary vane pump device according to claim 1, comprising a valve seat, an inner valve seat formed on the plunger, and a second spring that elastically supports the poppet valve in the axial direction.

Images