JPH0720392Y2 - Vacuum pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to a vane type vacuum pump which is formed so as to eliminate a side gap and increase the degree of vacuum.

2. Description of the Related Art A vane vacuum pump in a conventional example is formed so that a side surface of a rotor that rotates in a casing is guided by a fixed side plate. In other words, a gap is provided between the side surface of the rotor and the side plate. FIG. 3 is a vertical sectional front view showing an example of a conventional vane type vacuum pump, and FIG. 4 is a vertical sectional side view thereof. In the figure, 1 is a casing, 2 is a side plate, 3 is a rotor, 4 is a cover, and 5 is a lid. The rotor 3 is configured to be guided by the side plate 2 fixed to the casing 1 and the side plate 2 fixed to the cover 4 to rotate in the rotor chamber 6 of the casing 1 to perform suction and discharge. . A predetermined gap is provided between the side surface of the rotor 3 and the side plate 2 in order to prevent abrasion and seizure due to sliding of the side plate 2 and the roller 3.

Problems to be Solved by the Invention In the conventional vane type vacuum pump, the rotor 3 is used.
Then, due to leakage from the gap between the side plates 2 formed on both sides of the roller 3, the pump with a high degree of vacuum could not be formed. Further, if the clearance is eliminated, it becomes a sliding surface for solid contact, the side plate 2 or the rotor 3 is significantly damaged, and there is a problem that the vacuum pump becomes extremely inefficient.

This invention was made for the purpose of solving the above-mentioned conventional technology.

Means for Solving the Problems Means for solving the above problems will be described below with reference to FIGS. 1 and 2 corresponding to the embodiment. This invention has a casing 7 provided with a rotor chamber 8 having a circular cross section having a center eccentric to the rotation center of the rotor 11, and oil chambers 15 and 31 formed in circular bottomed holes. The anti-load-side cover 14 and the load-side cover 28 fixed to the rotor 11 and the rotor 11 which has the same axial length as the width of the casing 7 and rotates integrally with the drive shaft 22 in the rotor chamber 8.
And two sets of vanes 26 located on opposite sides of a regular quadrilateral centered on the rotor axis in the rotor 11 and pressed outward by elastic forces of springs 25, and the rotor 11 Of the rotor 11 and the bottom of the vane 26 in the rotor chamber 8 is pressed against the bottom surface of the vane 26 without a gap due to the pressing force of the spring, and the periphery has a slight gap with the end face of the casing 7. Side plates 9 and 10 that rotate with
And the pressing wheels 20 and 33 that are fixed to the anti-load side cover 14 and the load side cover 28 so as to move only in the axial direction and do not rotate and press the side plates 9 and 10, and the anti-load side cover 14 and the load side. It is arranged between the cover 28 and the pressing wheels 20, 33, and
Coil springs 21 and 34 for applying a pressing force to the pressure ring 2
In order to lubricate the sliding surface between 0 and 33 and the side plates 9 and 10 and the clearance between the outer peripheral portions of the side plates 9 and 10 and the end face of the casing 7,
The present invention relates to a vacuum pump including a lubricating oil filled in the oil chambers 15 and 31.

Action In the one thus constructed, the side plates 9 and 10 are
The inner peripheral portion is pressed against the side surfaces of the rotor 11 and the vane 26 without clearance, and the outer peripheral portion has a slight clearance with the end surface of the casing 7 and rotates integrally with the rotor 11. Further, the side plates 9 and 10 slide on the pressing wheels 20 and 33. further,
The lubricating oil is supplied to the sliding surfaces between the pressing wheels 20 and 33 and the side plates 9 and 10 and the clearance between the outer peripheral portions of the side plates 9 and 10 and the end surface of the casing 7.

Embodiments FIGS. 1 and 2 are views showing an embodiment of the present invention. In FIGS. 1 and 2, 7 is a casing, 14 is an anti-load side cover, 28 is a load side cover, 11 is a rotor, 26 is a vane,
Reference numerals 9 and 10 are side plates, 20 and 33 are pressing wheels, 21 and 34 are coil springs, and 15 and 31 are oil chambers. The casing 7 is provided with a circular rotor chamber 8 inside, and is provided with a suction port 12 and a discharge port 13 which are open on opposite sides in FIG. The counter-load side cover 14 is formed by providing an oil chamber 15 formed in a circular bottomed hole, and a bearing chamber 17 is provided in the center of the bottom wall portion 16 to insert and fix the bearing 18. Further, a disk-shaped side plate 9 with a boss that is loosely fitted to the inner peripheral surface of the oil chamber 15 is inserted with the boss portion 19 facing the bottom wall portion 16, and the side plate 9 is connected by a ring-shaped pressing wheel 20 and a coil spring 21. It is formed so as to be pushed outward of the oil chamber 15. In this case, the ring-shaped pressing wheel 20 itself is formed into a flat surface by cutting two opposite sides of the outer peripheral surface, and the flat surface is engaged with the wall of the oil chamber 15 so as not to rotate, and the coil spring 21 It is formed so that it can be moved in the opening direction of the oil chamber 15 by a pressing force.
Further, the side plate 9 is provided with a fitting hole 27 into which the drive shaft 22 is inserted at the center of the boss portion 19 so that the drive shaft 22 can be inserted so that the side plate 9 can rotate integrally with the drive shaft 22 and move axially. Fix it.

The counter-load side cover 14 is detachably fixed to one side end surface of the casing 7 in a state where the shaft center of the bearing 18 is eccentric by a predetermined eccentric amount such as a circular center of the rotor chamber 8 of the casing 7. In this case, the side plate 9 in the counter-load side cover 14 is formed in a circular shape having a radius that is the maximum distance from the center of the side plate 9 in the mounted state to the rotor chamber. That is, at the end edge of the one eccentric rotor chamber 8, the outer peripheral portion of the side plate 9 and the casing 7 are
Are slightly overlapped with each other, and the opposite edges are formed to be overlapped by the sum of the overlap and the eccentricity. The rotor 11 is formed of a solid cylindrical body that is detachably fixed to the drive shaft 22, and the axial length of the rotor 11 is the same as the width of the casing 7. Also, as shown in FIG. 2, the rotor 11
In a cross section perpendicular to the axis of, two sets of width-like grooves 23, 24 that open in opposite directions on the extension lines of two parallel sides of a regular quadrangle centered on the axis of the drive shaft 22 and extend over the entire length in the axial direction. To provide. A plurality of springs 2 are provided in the width grooves 23 and 24, respectively.
5 is inserted and fixed, and plate-shaped vanes 26 that are fitted into the width-shaped grooves 23, 24 in a sliding manner are inserted. That is, the vane 26 is formed so as to always project outward in the width-shaped grooves 23, 24.
The load side cover 28 is formed symmetrically with the anti-load side cover 14.
However, the only difference is that the shaft sealing ring 30 is provided so as to be connected to the outside of the bearing 29. That is, the oil chamber 31 and the bearing chamber 32 formed by circular bottomed holes and the bearing 29 in the bearing chamber 32.
Are fixed and formed. The oil chamber 31 communicates with the oil chamber 15.
Further, in the oil chamber 31, a side plate 10 and a pressing wheel for pressing the side plate 10 are provided.
33 and a coil spring 34 for pressing the pressing wheel 33. Either one of the side plates 9 and 10 may be formed integrally with the rotary. There is an advantage that the axial length can be reduced.

Next, the assembly procedure and the function of each part will be described.

First, insert the bearing 18 into the bearing chamber 17 of the cover 14 on the anti-load side and fix it, and use the outer peripheral wall of the bearing chamber 17 as a guide for the coil spring.
21 is fixed, the other end surface of the coil spring 21 is contacted, the pressing wheel 20 is moved in the axial direction, and is inserted so as not to rotate. The side plate 9 is axially moved to the drive shaft 22, and at the same time,
It is fixed so as to rotate integrally with the drive shaft 22. Further, the rotor 11 is in surface contact with the side plate 9, and the rotor 11 is fixed to the drive shaft 22 so as not to move in the axial direction and to rotate integrally with the drive shaft 22. One end of the drive shaft 22 is inserted into the bearing 18, the outer peripheral surface of the side plate 9 is slightly loosely fitted to the inner peripheral surface of the oil chamber 15, and the surface of the side plate 9 on the oil chamber 15 side is pressed. Form so that it is in contact with 20. Next, the casing 7 is placed in the rotor chamber 8
The vane 26 of the rotor 11 is inserted into the inner peripheral surface of the rotor 11 so as to be in contact therewith, and the shaft center of the rotor 11 and the circular center of the rotor chamber 8 are provided with a predetermined eccentric amount, and are connected to the anti-load side cover 14.
In this state, in order to prevent wear and seizure due to sliding between the side plate 9 and the end surface of the casing 7, the outer peripheral portion of the side plate 9 faces the end surface of the casing 7 with a slight gap, and the inner side of the side plate 9 is prevented. The peripheral portion is in pressure contact with the side surfaces of the rotor 11 and the vane 26 by the pressing force of the coil spring 21 without clearance. The load side cover 28 also inserts and fixes the bearing 29, and fixes the coil spring 34 by using the outer peripheral surface of the bearing chamber 32 as a guide so that the other end surface of the coil spring 34 does not move but rotate in the axial direction. Load side cover 28
It is formed by providing a pressing wheel 33 fixed to the wall meat. Side plate
10 is fixed to the drive shaft 22 so as to move in the axial direction and rotate integrally with the drive shaft 22. The load side cover 28 is also connected to the casing 7 with a predetermined eccentric amount. In this state, similarly to the side plate 9, the side plate 10 faces the end surface of the casing 7 with a slight gap and is in pressure contact with the side surfaces of the rotor 11 and the vane 26. The outer peripheral surface of the side plate 10 is slightly loosely fitted to the inner peripheral surface of the oil chamber 31.
Now, when the drive shaft 22 is rotated, the rotor 11 is rotated integrally with the drive shaft 22, and the vane 26 is rotated by the pressing force of the spring 25 while constantly contacting the rotor chamber 8 and the inner peripheral surface. At the same time, the side plates 9 and 10 rotate integrally while sandwiching both side surfaces of the rotor 11. In this case, the side plate 9 rotates with the contact surface with the pressing wheel 20 as the sliding surface, and the side plate 10 rotates with the contact surface with the pressing wheel 33 as the sliding surface. Therefore, there is no gap in the rotor chamber 8, and there is only a slight gap between both end faces of the casing 7 and the outer peripheral portions of the side plates 9 and 10. Oil chamber
Lubricating oil is filled in 15,31, and the sliding surface between the pressing wheel 20 and the side plate 9, the sliding surface between the pressing wheel 33 and the side plate 10, the clearance between the side plate 9 and the casing 7, and the clearance between the side plate 10 and the casing 7 are provided. Lubricate.

Effect According to the present invention, the side plate is rotated integrally with the rotor while being in pressure contact with the side surfaces of the rotor and the vane and in pressure contact with the end surface of the casing through the lubricating oil, so that there is no side surface clearance. The amount of leakage from the side surface that returns to the suction side through this gap becomes "0". Therefore, a vacuum pump having a high degree of vacuum can be formed. According to the embodiment, a vane type vacuum pump having a rotation rate of 1450 rpm and a rated discharge rate of 160 liters / minute, the conventional pump having a vacuum degree of 450 mm mercury column is the same as the vacuum pump according to the present invention. You are getting 680 mm mercury column in the condition. Further, except for the tip of the vane, the sliding contact between the solids is the sliding surface between the pressing wheel and the side plate and the sliding surface between the outer peripheral portion of the side plate and the casing 7. This part is lubricated. It is possible to suppress the frictional resistance to a low level, and it is possible to provide a vacuum pump with high overall efficiency.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a vane type vacuum pump according to the present invention, and FIG. 2 is a vertical sectional side view thereof. FIG. 3 is a vertical sectional front view showing an example of a conventional vane type vacuum pump, and FIG. 4 is a vertical sectional side view thereof. 7 ... Casing, 8 ... Rotor chamber, 9, 10 ... Side plate,
11 …… Rotor, 14 …… Anti-load side cover, 15,31 …… Oil chamber, 20,33 …… Pressing ring, 21,34 …… Coil spring, 22
...... Drive shaft, 26 …… Vane, 28 …… Load side cover

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-54-90009 (JP, A) Actually open 50-152210 (JP, U) Actual-opening Sho-56-17389 (JP, U) Actual public 47- 18211 (JP, Y1)

Claims (1)

[Scope of utility model registration request] 1. A casing 7 provided with a rotor chamber 8 having a circular cross section having a center eccentric to the center of rotation of a rotor 11, and
The oil chambers 15 and 31 formed in circular bottomed holes are provided, and the anti-load side cover 14 and the load side cover 28 fixed to both end surfaces of the casing 7 have the same axial length as the width length of the casing 7. And a rotor 11 that is integrally formed with the drive shaft 22 in the rotor chamber 8 and that are located on opposite sides of a regular quadrilateral centered on the rotor axis center in the rotor 11 and in opposite directions outward. 2 sets of vanes 26 that are pressed by the elastic force of the spring 25 and the outer diameter of the rotor 11, and the inner peripheral portion is pressed against the side surfaces of the rotor 11 and the vanes 26 in the rotor chamber 8 against the side surface of the spring without a gap. However, the outer periphery is the casing 7.
End plates and a slight clearance, and the side plates 9 and 10 that rotate together with the rotor 11, and the anti-load side cover 14 and the load side cover 28 are fixed so as not to rotate and move only in the axial direction. Coil spring 2 which is arranged between pressing wheels 20 and 33 that press 10 and anti-load side cover 14, load side cover 28 and pressing wheels 20 and 33, and applies a pressing force to pressing wheels 20 and 33.
Oil chambers 15 and 31 are filled in order to lubricate the sliding surfaces of 1, 34, the pressing wheels 20, 33 and the side plates 9, 10 and the clearance between the outer peripheral portions of the side plates 9, 10 and the end surface of the casing 7. Vacuum pump consisting of lubricating oil