JPH0588391B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oil supply device for an oil rotary vacuum pump.

[Prior Art] Conventionally, oil rotary vacuum pumps in which a rotor fixed to a rotor shaft is rotated in a cylinder chamber are equipped with an oil supply device for oil rotary vacuum pumps that can supply oil from an oil reservoir chamber into a cylinder chamber. It becomes. That is,
The oil rotary vacuum pump sequentially supplies a predetermined amount of oil into the cylinder chamber in order to lubricate the rotor rotating within the cylinder chamber and ensure airtightness between the rotor and the inner wall of the cylinder chamber. For this reason, the conventional oil supply device sequentially supplies oil from the oil reservoir chamber through the negative pressure into the cylinder chamber, which is made to have a negative pressure under the rotating state of the rotor.

However, in the oil supply system for the oil rotary vacuum pump as described above, when the pump operation is stopped, the vacuum system path including the cylinder chamber becomes negative pressure, so the oil in the oil reservoir chamber is reduced by the negative pressure. will be supplied to the cylinder chamber etc. in excess. Therefore, when restarting the pump, a large starting torque was required for the rotor due to the excess oil supplied into the cylinder chamber. In particular, when the oil cools, the viscous resistance increases and it takes time for the rotor to reach steady operation.

In order to solve these problems, the applicant has made a proposal as described in Japanese Patent Publication No. 7840/1983. According to this proposal, oil is sequentially supplied into the cylinder chamber when the pump is operating, and even though a small amount of oil may be supplied to the cylinder chamber when the pump is stopped, it will not interfere with restarting the pump. The problems caused by the supply of large amounts of oil have now been resolved.

[Problems to be Solved by the Invention] However, in the conventional oil supply device for the oil rotary vacuum pump described above, oil is supplied into the cylinder chamber through negative pressure in the cylinder chamber. This was inefficient in terms of providing a stable supply of oil. In particular, when the pump was stopped and then restarted, it took a long time for the oil to be stably supplied, making the lubricity and airtightness unstable.

An object of the present invention is to stably supply oil into the cylinder chamber of an oil rotary vacuum pump and to stabilize the lubricity and airtightness during operation of the pump.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a system in which oil in an oil reservoir can be supplied into a cylinder chamber while a rotor fixed to a rotor shaft is rotated in the cylinder chamber. An oil supply system for an oil rotary vacuum pump includes an oil supply pump connected to a rotor shaft and capable of pumping oil in an oil reservoir chamber into a cylinder chamber via an oil supply passage, and a vacuum pump interposed in the oil supply passage. The engine is equipped with an on-off valve that closes against negative pressure in the cylinder chamber when the engine is stopped.

[Operation] According to the present invention, when the oil rotary vacuum pump is operated, the oil supply pump is reliably driven in conjunction with the rotor shaft, making it possible to ensure the supply of oil into the cylinder chamber. Become. This makes it possible to stabilize the lubricity and airtightness during operation of the pump.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

Fig. 1 is a cross-sectional view showing a lubricating device for an oil rotary vacuum pump according to an embodiment of the present invention, Fig. 2 is a view taken along the - line in Fig. 1, and Fig. 3 A and B are respective opening/closing valves. Fig. 3A is a sectional view showing the on-off valve in the open state, Fig. 3B is a sectional view showing the on-off valve in the closed state, and Fig. 4 is a sectional view taken along the - line in Fig. 1. It is.

As shown in FIG. 4, the oil rotary vacuum pump 10 has a housing 11 as an oil reservoir chamber 12, and a substantially cylindrical rotor housing 13 is provided within the oil reservoir chamber 12. Inside the rotor housing 13 is a cylinder chamber 14, and a rotor shaft 15 is disposed in the cylindrical axis direction of the cylinder chamber 14. The rotor shaft 15 can be rotated in the direction of arrow A by driving a drive motor (not shown). Rotor shaft 15
A cylindrical rotor 16 is supported.
The rotor 16 can be rotated in the direction of arrow A within the cylinder chamber 14 by rotation of the rotor shaft 15. The rotor shaft 15 in the cylinder chamber 14 is eccentrically disposed in the cylinder chamber 14 having a circular cross section, so that the rotor 16 supported by the rotor shaft 15 also rotates within the cylinder chamber 14. It will be eccentrically arranged with its upper side in contact with the inner wall.

An insertion hole 17 is formed in a direction [B direction] perpendicular to the axial directions of the rotor shaft 15 and the rotor 16, and a compression spring 18 is disposed at the center of the insertion hole 17. Furthermore, vanes 19 are disposed at both ends of the compression spring 18, and each vane 19 is brought into contact with the inner wall of the cylinder chamber 14 by the biasing force of the compression spring 18.

A suction port 20 and a discharge port 21 are formed on the inner wall of the cylinder chamber 14 against which the vane 19 comes into contact, respectively. The suction port 20 communicates with an air intake port 22 located above the housing 11, and a pump hose connected to a vacuum chamber, for example, can be connected to the air intake port 22. On the other hand, the discharge port 21
communicates with the oil reservoir chamber 12, and a valve body 23 is disposed on the oil reservoir chamber 12 side of the discharge port 21.

The oil rotary vacuum pump 10 is operated by the rotation of a rotor 16 driven by a driving motor, and this operation is performed by continuously rotating the vane 19 in the direction of arrow A, which is in contact with the inner wall of the cylinder chamber 14. As a result, air can flow into the cylinder chamber 14 through the suction port 20, and furthermore, the air that has flowed into the cylinder chamber 14 can be discharged through the discharge port 21. The air discharged from the discharge port 21 flows into the oil reservoir chamber 1.
The oil is discharged into the oil reservoir chamber 12, and is further opened to the atmosphere from the oil reservoir chamber 12. At this time, the discharge port 21
The valve body 23 disposed in the oil reservoir chamber 12 prevents the oil in the oil reservoir chamber 12 from entering the cylinder chamber 14 .

In this way, the oil rotary vacuum pump 10 can sequentially draw in air from the suction port 20 by continuous rotation of the rotor 16. As a result, by connecting, for example, a pump hose connected to a vacuum chamber to the air intake port 22 communicating with the suction port 20, it is possible to evacuate the inside of the vacuum chamber.

One end side of the rotor shaft 15 is a shaft bearing portion 24 of the rotor shaft 15, as shown in FIG.
A bearing 25 is disposed between the rotor shaft 15 and the rotor shaft 15 . Shaft bearing part 24 for inside of cylinder chamber 14
An oil supply pump 26 is disposed outside the pump housing 27, and the oil supply pump 26 is disposed inside the pump housing 27. That is, the pump housing 27
An oil supply cylinder chamber 28 having a substantially circular cross section as shown in FIG. 2 is formed inside the cover 27A. This cylinder chamber 28 is connected to a support hole 29 of the rotor shaft 15 in the bearing portion 24, and a connecting shaft 30 connected to the rotor shaft 15 is disposed within the cylinder chamber 28. Furthermore, a sealing material 30A is provided in the support hole 29 to partition the bearing 25 side and the cylinder chamber 28 for oil supply. The connecting shaft 30 is rotatable in the direction of arrow A as the rotor shaft 15 rotates.
As shown in FIG. 2, there is a rotor 31 with a circular cross section.
is supported. The rotor 31 can be rotated in the direction of arrow A within the cylinder chamber 28 as the connecting shaft 30 rotates. The connecting shaft 30 in the cylinder chamber 28 is arranged eccentrically in the cylinder chamber 28 having a circular cross section, so that the connecting shaft 30
The rotor 31 supported at zero is also eccentrically arranged within the cylinder chamber 28 so as to be in contact with the inner wall of the cylinder chamber 28 .

As shown in FIG. 2, an insertion hole 32 is bored in a direction [direction B] perpendicular to the axial directions of the connecting shaft 30 and the rotor 31, and a diameter approximately equal to the diameter of the cylinder chamber 28 is formed in the insertion hole 32. One vane 34 having the same length is provided, and both ends of the vane 34 abut against the inner wall of the cylinder chamber 28 .

An oil inlet 35 and an oil outlet 36 are provided on the inner wall of the cylinder chamber 28 against which the vane 34 comes into contact, respectively.
are formed, and the oil inlet 35 and oil outlet 36
are arranged at substantially opposite positions in the cylinder chamber 28 having a circular cross section. The oil inlet 35 is
It communicates with the oil reservoir chamber 12 via a suction passage 37 formed in the cover 27A. On the other hand, the oil discharge port 36 is
It is communicated with the cylinder chamber 14 via an oil supply path 38 formed in the pump housing 27 and the bearing portion 24 . Further, an oil supply path 38 formed in the pump housing 27 is communicated with the oil reservoir chamber 12 via a relief hole 39 . An on-off valve 40 is interposed in the oil supply path 38 formed in the bearing portion 24, and the on-off valve 40 closes against negative pressure in the cylinder chamber 14 that occurs when the oil rotary vacuum pump 10 is stopped. . That is, the on-off valve 40 applies the spring force of the compression spring 41 constituting the on-off valve 40 in advance so that the on-off valve 40 is closed against the negative pressure generated in the cylinder chamber 14 when the pump 10 is stopped. It is set.

In addition, in the figure, 13A is a sealing material provided on the mating surface of the rotor housing 13 and the shaft bearing part 24;
A indicates a sealing material provided on the mating surface of the shaft bearing 24 and the pump housing 27, and 27B indicates a relief hole provided in the pump housing 27 to communicate the oil reservoir chamber 12 and the support hole 29.

The oil supply pump 26 is operated as the vacuum pump 10 is operated, and is driven as the rotor shaft 15 rotates. That is, when the rotor shaft 15 is rotated, the connecting shaft 30 connected thereto is rotated, and as a result, the rotor 31 is rotated in the direction of arrow A within the oil supply cylinder chamber 28. When the rotor 31 is rotated, the cylinder chamber 28
The vane 34 that comes into contact with the inner wall of the vehicle is continuously rotated in the direction of arrow A. This allows the oil in the oil reservoir chamber 12 to flow into the cylinder chamber 28 from the oil suction port 35. Furthermore, the cylinder chamber 28
The oil flowing into the inside is discharged from the discharge port 36,
The oil can be supplied to the oil supply path 38. Note that in the cylinder chamber 28, oil discharged into the support hole 29 through the minute gap between the rotor 31 and the pump housing 27 is returned to the oil reservoir chamber 12 from the escape hole 27B, and the oil that is more than necessary is returned to the oil reservoir chamber 12 through the escape hole 27B. Pressure is prevented from being applied to the sealing material 30A. Now, the oil supplied to the oil supply path 38 is pumped in the direction of arrow C, and through the pumping force of this oil, the on-off valve 40 is moved as shown in FIG. 3A.
will open. That is, the compression spring 41 constituting the on-off valve 40 is set to have a spring force smaller than the sum of the hydraulic power of the oil supply pump 26 and the negative pressure inside the cylinder chamber 14 . When the on-off valve 40 opens as shown in FIG. 3A, the oil in the oil reservoir chamber 12 is continuously supplied into the cylinder chamber 14 via the oil supply path 38. As a result, the supplied oil ensures lubrication of the rotor 16 rotating within the cylinder chamber 14 and airtightness between the vane 19 and the inner wall of the cylinder chamber 14. A portion of the oil supplied to the oil supply path 38 is circulated to the oil reservoir chamber 12 via the relief hole 39. Relief hole 39
Nozzles 42 having various nozzle diameters D can be attached to the outlet portion of the oil sump chamber 1 through the relief hole 38 by selectively attaching each nozzle 42.
2. The amount of oil discharged can be variably adjusted.
As a result, it becomes possible to variably adjust the pumping force and flow rate of the oil pumped to the on-off valve 40 side via the oil supply path 38 by selecting the nozzle 42 .

When the operation of the oil rotary vacuum pump 10 is stopped and the rotation of the rotor shaft 15 is stopped, the rotation of the connecting shaft 30 connected to the rotor shaft 15 is stopped. As a result, the operation of the oil supply pump 26 is stopped, and the supply of oil pumped in the direction of arrow C through the oil supply path 38 is also stopped. Along with this, the third
As shown in Figure B, the on-off valve 40 pushed by the spring 41 having a spring force greater than the negative pressure in the cylinder chamber 14 closes the oil supply path 38 against the negative pressure in the cylinder chamber 14. Therefore, the supply of oil into the cylinder chamber 14 is completely cut off. When the oil rotary vacuum pump 10 that has been stopped is restarted, the oil supply pump 26 is activated again in the oil supply path 3.
8, and the on-off valve 40 is opened. When the on-off valve 40 opens, the oil whose supply was cut off by the valve 40 immediately flows into the cylinder chamber 14.
It will be supplied within Therefore, it is possible to immediately and stably supply oil into the cylinder chamber 14 even when the engine is restarted.

Next, the operation of the oil rotary vacuum pump supply device according to the above embodiment will be explained.

According to the above embodiment, when the oil rotary vacuum pump 10 is operated, the oil supply pump 26 is reliably driven in conjunction with the rotor shaft 15 to ensure the supply of oil into the cylinder chamber 14. becomes possible. Thereby, it is possible to stabilize the lubricity and airtightness during operation of the pump 10, regardless of whether it is at startup or during continuous operation.

Further, by selectively attaching nozzles 42 having various nozzle diameters D, an appropriate amount of oil can always be supplied to the oil rotary vacuum pump 10 in operation.

[Effects of the Invention] As described above, the present invention provides the following advantages: under the condition in which the rotor fixed to the rotor shaft is rotated within the cylinder chamber,
In an oil supply system for an oil rotary vacuum pump that can supply oil from an oil reservoir into a cylinder chamber, an oil supply pump is connected to a rotor shaft and can pump oil from an oil reservoir into a cylinder chamber through an oil supply path. and an on-off valve that is interposed in the oil supply path and closes against negative pressure in the cylinder chamber when the vacuum pump is stopped, thereby stably supplying oil into the cylinder chamber of the oil rotary vacuum pump and increasing the efficiency of the pump. This has the effect of stabilizing lubricity and airtightness during operation.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a lubricating device for an oil rotary vacuum pump according to an embodiment of the present invention, Fig. 2 is a view taken along the - line in Fig. 1, and Fig. 3 A and B are respective opening/closing valves. Fig. 3A is a sectional view showing the on-off valve in the open state, Fig. 3B is a sectional view showing the on-off valve in the closed state, and Fig. 4 is a sectional view taken along the - line in Fig. 1. It is. 10...Oil rotary vacuum pump, 12...Oil sump chamber,
14... Cylinder chamber, 15... Rotor shaft, 16...
... Rotor, 26 ... Oil supply pump, 38 ... Oil supply path, 40 ... Opening/closing valve.

Claims (1)

[Claims] 1 In an oil supply device for an oil rotary vacuum pump that is capable of supplying oil from an oil reservoir into a cylinder chamber while a rotor fixed to the rotor shaft rotates within the cylinder chamber, It has an oil supply pump that can pump oil into the cylinder chamber through an oil supply path, and an on-off valve that is interposed in the oil supply path and closes against negative pressure in the cylinder chamber when the vacuum pump is stopped. Oil supply device for oil rotary vacuum pump.