JPS59183094A - Air pump - Google Patents

Abstract

PURPOSE:To improve durability of respective bearings as well as the performance of the pump by a method wherein loads are reduced in the bearings supported on a vane shaft while rotating speeds are reduced in the bearings supported by an intermediate sleeve member respectively. CONSTITUTION:A pair of needle bearings 16A, 16A, supporting one sheet of vane 9 among three sheets of vanes 9 supported with respect to the vane shaft 10, are mounted on the vane shaft 10 at both end sides thereof. The intermediate sleeve member 30 is supported rotatably on the vane shaft 10 by the pair of needle bearings 16A, 16A in loose conditions. The needle bearings 16B, 16B, 16C, 16C, supporting remaining vanes 9, are mounted on the intermediate sleeve member 30. According to this method, the loads therefor are reduced in the outside needle bearings 16A, 16A while the rotating speeds are reduced in the inside needle bearings 16B, 16B, 16C, 16C, therefore, the durability of respective bearings may be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a vane type air pump, and more particularly to an improvement in the air pump that can improve the durability of a vane support portion rotatably supported on a vane shaft. .

[Prior art]

For example, secondary air supply devices used to purify automobile exhaust gas, and superchargers, which have been developed in recent years with the aim of improving automobile engine output and fuel efficiency, are A vane type air pump is used as a driving source, and the above purpose is achieved by supplying air from the pump to the exhaust system or intake system of the engine.

Such vane-type air pumps generally include a rotor with a plurality of vanes and a vane shaft that supports the vanes built into an internal space, a pump chamber that houses the rotor, and suction and discharge passages on both sides of the rotor. The pump housing has a Then, by rotating the rotor around a position eccentric to the vane shaft located on the axis of the pump chamber, each vane is rotated while moving forward and backward with respect to the pump chamber. Various structures have been known in the art for sending the air guided through the passage to the discharge side passage and discharging it from the discharge port.

By the way, in a vane-type air pump having such a configuration, the vanes are rotatably supported by a vane shaft, which is a fixed shaft, through a pair of bearings each incorporated in a vane holder. Bearings rotate at high speed along with the rotor, and are subjected to high loads during this rotation, so the pv value (P
; load, v: rotational speed) is large. In particular, in this type of air pump, needle bearings are generally used as the vane support bearings mentioned above due to their space and ease of assembly, and the large pv value of such needle bearings is not uncommon. This is a big problem in terms of durability.)
In the end, the durability of this needle bearing was one of the major factors in determining pump life.

For such needle bearings, the leakage of grease under high temperature conditions during pump operation is one of the factors that shortens the life of the needle bearing, and the thrust force generated due to its structure acts on the vane. In particular, there is a problem in which the side seals of the vanes wear out, reducing the durability of the pump and even lowering the performance of the pump.) Taking these points into consideration, we will improve the vane support. It is hoped that

[Summary of the invention]

The present invention has been made in view of these circumstances.
One of the plurality of vanes supported on the vane shaft is supported on the vane shaft via a pair of bearings, and the intermediate sleeve member is rotatably supported on the vane shaft using these bearings. death,
This simple configuration in which the remaining vanes are supported by this intermediate sleeve member reduces the load acting on the bearings that support each vane or its rotational speed, thereby reducing the pv value of each vane and increasing its durability. An object of the present invention is to provide an air pump whose performance can be greatly improved.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

1 and 2 show an embodiment of the vane type air pump according to the present invention. In these figures, first, the general structure of the air pump as a whole will be briefly explained. , inside thereof there is a pump chamber 1a and suction side and discharge side passages 1b.

In this example, the pump housing is formed by forming a housing main body 2 having a substantially cylindrical shape formed by cutting an extruded or pultruded elongated vibrator to a desired length, and a pump housing formed by forming a pump housing 1c, which is joined to both ends of the housing main body 2. It consists of a front cover 3 and a rear cover 4.

Reference numeral 5 denotes a rotor disposed in the pump chamber 1a, which includes a cylindrical rotor body 6 formed by cutting an extruded or pultruded long pipe similar to the housing body 2, and a rotor body 6 attached to both ends of the rotor body 6. It consists of a front camp T and a rear camp 8. Three vanes 9 and a vane shaft 10 that rotatably supports the vanes 9 are integrally assembled inside the rotor 5. In addition, at three locations on the outer periphery of the rotor 5,
A slit 11 for allowing the vane 9 to move in and out is formed along the axial direction. In addition, in the figure, 12.13 is a gasket as a seal interposed between the rotor body 6 and both camps 1.8, 14 is a bolt for fixing both caps 7.8 to the rotor body 6, and 15 (15A,
1513, 15C) are a pair of needle bearings 16 (16A).

16B, 16C)'e This is a vane holder that supports each vane 9 on the vane shaft 10 via. Also,
The front cap 7 is integrally formed with a rotor shaft 7m projecting outward, while the rear cap 8 has a shaft hole 8a bored in its center.

The rotor 5 configured as described above is supported by the front cover 3 and rear cover 4 that constitute the housing 1 at a position eccentrically upward from the axis of the pump chamber 1a (indicated by R0 in FIG. 2). , while vane shirt)
10 is supported at a position eccentric from the axis of the pump chamber 1a (indicated by ■ in FIG. 2), that is, from the axis of the rotor 5.

That is, the rotor shirt 7a of the front camp 7 of the rotor 5 is pivotally supported by the front cover 3 of the housing 1 via a bearing 17, and the shaft hole 8a of the rear camp 8 is supported by the bearing 18 to the rear cover 4.
It is pivotally supported by a boss part Ja. One end of the vane shaft 10 is supported within the front cap I via a hanger portion 10a, and the rotor 5 is rotatable relative to the vane shaft 10 by a bearing 19. Further, the other end of the vane shaft 10 is connected to a part of the boss portion 4& of the rear cover 4 by a Nikie 20, etc., and is fixed by a Nand 21.

Incidentally, reference numerals 22 in the figure indicate bolts for fixing the covers 3 and 4 to both ends of the housing body 2 constituting the housing 1. In the figure, reference numeral 23 denotes a pulley that receives rotation transmission from the automobile engine through a V-belt or the like, and is supported on the rotor shaft 7a via a well-known electromagnetic clutch 24.
a is selectively connected to the pulley 23. Further, the rear cover 4 of the housing 1 is formed with a suction port 25 and a discharge port (not shown) which communicate with the suction side and discharge side passages 1b and 1c, respectively.

In such a configuration, when the rotor 5 rotates, the vanes 9 on the vane shirt 10 rotate together, and the vanes 9 move back and forth through the slit 11 on the outer periphery of the rotor 5 while rotating within the pump chamber a. As a result, the air guided from the suction port 25 into the suction side passage 1b passes through a passage formed on the outside of the rotor 5 by the outer periphery of the rotor 5 and the pump chamber 1a, and then flows to the discharge side. It is sent out from a discharge port (not shown) through a passage 1c.

Now, according to the present invention, in the air pump having the above-described configuration, a pair of needle bearings 16A supports one of the three plates 79 supported with respect to the vane shirt 10.

16A are mounted on both end sides of the vane shaft 10, and these pair of needle bearings 16
A and 16A are needle bearings that rotatably support the intermediate sleeve member 30 having a substantially cylindrical shape on the vane shaft 10 in a loosely fitted state, and support the remaining vanes 9 on the intermediate sleeve member 30; 16B, 16B;
The feature is that 160, 160 are mounted on shafts.

To explain this in detail using FIG. 1 and further FIG. 3, the intermediate sleeve member 30 has the needle bearing 16A,
a large diameter portion 30a forming an annular space in which 16A is interposed;
30a, and a small diameter portion 30b extending along the axial direction of the vane shaft 10 between the large diameter portions 30a, 30a and having an inner diameter slightly larger than the outer diameter of the vane shaft 10. There is. The large diameter portions 30m and 30m of the intermediate sleeve member 300 are held by a first vane holder 15A that supports the vane 9, whereby the vane 9 is rotatably supported on the vane shaft 10. Also, a vane holder 15B supports the remaining vanes 9.

Needle bearing 16B built into 15C.

16B; 16C and 16C are mounted on the outside of the small diameter portion 30b of the intermediate sleeve member 30. In FIG. 3, the portion of the vane shaft 10 corresponding to the small diameter portion 30b of the intermediate sleeve member 30 is formed to have a small diameter, and the grease IJ-sump from the grease filling passage 31, which will be described later, and the needles at both ends of the vane shaft 10 are formed to have a small diameter. The structure is substantially the same as that shown in FIG. 1, although the structure is shown to have a function of smoothing the supply of grease to the bearings 16A, 16A.

According to this configuration, the vane shaft 10
Outer needle bearings 16A, 16 mounted on the side
In A, the load is reduced, and the inner needle bearing 16B is mounted on the intermediate sleeve member 30 side.
, 16B; 16C and 16C have lower rotational speeds, which makes it possible to reduce the PV value of each of these needle bearings 16A, 16B and 16C and improve their durability.

First, let's talk about the rotational speed of each bay 79 and the 21 dollar bearings 16A, 16B, and 16C that support them.As shown in FIG. As is clear from FIGS. 2 and 4, the rotation speed of the vanes 9, which are equally spaced at intervals of , is the minimum circumferential speed when passing through the rotation center RO of the rotor 5 at 0 degrees Furthermore, rotor 5 at 105 degrees
It is represented by characteristic curves A, B, and C that coincide with the peripheral speed of the rotor 5, reach the maximum peripheral speed at 180 degrees, and again match the peripheral speed of the rotor 5 at 255 degrees. here,
In Fig. 4, A shows the characteristic curve for the vane 9 supported by the outer needle bearing 16A, and B and C show the characteristic curve for the vane 9 supported by the inner needle bearings 16B and 16C, each of which is shifted by 120 degrees. The same pattern as shown in FIG.

However, as in the present invention, the outer needle bearing 16
The actual rotational speed of the needle bearing i5B, 160 supported by the intermediate sleeve member 30 that rotates together with A is determined by the relative speed difference between the two.
A), F (C-A), it is easy to understand that the rotational speed is lower than that in the conventional case in which the vane shaft 10 is directly supported. The lower rotational speed of the inner needle bearings 16B and 16C results in a smaller pv value of these bearings, thereby improving the durability of these inner needle bearings 16B and 16C. It is something. In addition, these needle bearings 1
As is clear from the characteristic curves E and F in FIG. 4, the rotations of 6B and 16C are such that they rotate alternately in both the forward and reverse directions for one revolution of the vane 9, and this results in the rotation of the vane 9. There is also the advantage that the thrust force acting on the pump 9 is offset and reduced, and wear of the side seal portion of the vane, which affects pump durability and performance, can be reduced. This is clear from the fact that the direction in which the thrust force exerted by a needle bearing is generally determined by the direction of its rotation. It goes without saying that the rotational speed of the outer needle bearing 16A follows the same pattern as the conventional one shown by A in the figure.

Also, each needle bearing 1 is rotated by the rotation of the vane 9.
The loads applied to 6A, 16B, and 16C are as shown in FIG. That is, the inside of the figure represents the load acting on the large diameter portion 30m of the intermediate sleeve member 30 supported by the outer needle bearing 16A by the vane 9, and B and C represent the load applied to the inner needle bearings 16B and 16C. are shown respectively. What should be noted here is that, as shown in FIG. 6, the load F that actually acts on the outer needle bearing 16A is the resultant force (sin
3 Q°(B-1-C)) acts as a reaction force on the intermediate sleeve member 30, so these forces cancel each other out and form the characteristic curve shown by F in the figure, which is sufficiently reduced compared to the conventional case. This results in Therefore, it is easy to understand that this load reduction reduces the pv value of the outer needle bearing 16A and improves durability.

Therefore, with such a configuration, by skillfully utilizing the intermediate sleeve member 30, the pv value can be reduced by reducing the load on the outer needle bearing 16A and reducing the rotational speed on the inner needle bearings 16B and 16C. It is effective in suppressing heat generation in each part to reduce the load or rotation speed mentioned above and further improving durability. This can also be effective in reducing the thrust force acting on the side seals and preventing wear on the side seals.

In addition, in the configuration using the intermediate sleeve member 3o described above, the space formed between the sleeve member 3o and the vane shaft 10 is filled with the outer needle bearing 16A,
Grease supply path and grease reservoir for 16A-ib
It has great advantages, and if a grease supply passage 31 is provided in the vane shaft 10 as shown in Figs. 1 to 3, it is possible to sequentially supply grease from the outside. As a result, the outer needle bearing 16A has a high rotational speed.

This is effective in improving the lifespan of 16A.

Here, the opening of the passage 31 in the vane shaft 10 need only be provided at one location in the center of the shaft 10, which has the advantage of being easy to form. Further, 32 in FIG. 1 is a grease nipple.

Note that the present invention is not limited to the structure of the embodiment described above, and the shape, structure, etc. of each part may be modified as necessary.

Needless to say, it can be changed. For example, in the embodiment described above, the intermediate sleeve member 3 is mounted on the vane shaft 10.
0 and the vane 9, the present invention is not limited thereto, and as shown in FIG. 7 or 8, both or one of them may be replaced with a ball bearing 33. Free 1))
It is obvious that this can greatly improve the durability, strength, etc. of the vane support. Further, as shown in FIG. 8, the strength of the vane shaft 10 can be improved by forming a part of the vane shaft 10 with a large diameter part 34 and supporting the needle bearing 16A in this part. There are also advantages.

〔Effect of the invention〕

As explained above, according to the air pump according to the present invention, a pair of bearings that support one of the plurality of vanes supported on the vane shaft are mounted on the vane shaft, and , These bearings rotatably support the υ intermediate sleeve member on the vane shaft, and the remaining vanes are supported by this intermediate sleeve member. The load on the supported bearing can be reduced, and the rotational speed of the bearing supported on the intermediate sleeve member can be reduced, thereby reducing the respective Pv values and improving their durability. It also suppresses heat generation at the vane support part.
It is possible to significantly extend the life of the bearings, and it is also possible to reduce the thrust force acting on the vanes, reducing wear on the side seals of the vanes, thereby improving the durability of the entire pump and pump performance. There are various excellent effects such as improved performance.

[Brief explanation of drawings]

FIGS. 1 and 2 are a longitudinal cross-sectional view of the entire air pump showing an embodiment of the present invention, and a cross-sectional view taken along the line ■-■, and FIG. 3 is a schematic configuration of the main parts showing an enlarged view of the main parts. figure,
4 to 6 are characteristic diagrams and operation explanatory diagrams for explaining the effects of the present invention, and FIGS. 7 and 8 are diagrams showing other embodiments of the present invention. 1...Housing, 5...Rotor, 9...
Vane, 10... Vane shaft, 15 (15A,
15B, 15C)... Vane holder, 16 (16A
, 16B, 160)...Needle bearing, 30
...Intermediate sleeve member, 30a...Large diameter portion, 3
0b...Small diameter part, 33...Ball bear link. Patent applicant: Automotive Equipment Co., Ltd. Agent: Masaki Yamakawa (and one other person) 57
9? □;! 31:i'1 9 Kinobeden banknote

Claims (1)

[Claims] In an air pump in which a plurality of vanes are rotatably supported via a pair of bearings on a vane shaft supported within a rotor, a pair of bearings that support one vane are mounted on a shaft on the vane shaft. An air pump characterized in that an intermediate sleeve member is rotatably supported on the vane shaft by these bearings, and the remaining vanes are supported by the intermediate sleeve member.