JPS59105989A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To make a balance weight unnecessary and obtain a space for a thrust bearing sufficiently by a method wherein a follower link is interposed between a rocking scroll and a driving shaft and the bearing clearance of the follower link is set larger than the same of a main bearing to utilize the component of the resultant of a gas compressing load and a centrifugal force, acting on the rocking scroll, for the radial sealing force of a scroll. CONSTITUTION:The follower link 18 is interposed between the rocking scroll 2 and the driving shaft 10, the follower link pin 11 of the driving shaft 10 is engaged with the follower link pin hole 13 of the follower link 18, a bearing 7 is engaged with and fixed to the eccentric hole 6 of the follower link 18 and the shaft 8 of the rocking scroll 2 is engaged rotatably with the bearing 7. The large diametral part of the driving shaft 10 is engaged with the main bearing 15 of the fixed side rotatably while the follower link 18 is engaged with the part of the extension of the main shaft 15 on the driving shaft 10. The outer diameter of the follower link 18 is formed so as to be smaller than the large diametral part of the driving shaft 10. A straight line, connecting the center O'' of the follower link pin 11 and the center O' of eccentricity, intersects with the resultant F of the loads with an angle of several degrees to several ten degrees.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a scroll compressor with improved radial sealing of the swirl.

Before entering into the description of this invention, the operating principle of a scroll compressor will be explained.

The basic components of a scroll compressor are shown in Figure 1. Figures 1 (a), (b), (C)
, (d), 1 is a fixed scroll, 2 is an oscillating scroll, 3 is a discharge port, 4 is a compression chamber, 0 is the center of the fixed scroll 1, and 0' is the center of the oscillating scroll 2. The fixed scroll 1 and the oscillating scroll 2 have spirals having the same shape and opposite winding directions, and the shape of these spirals is an involute or a combination of circular arcs, etc., and a compression chamber 4 is located between the spirals. It is formed.

Next, the operation will be explained. In FIG. 1, a fixed scroll 1 is stationary with respect to space, and an oscillating scroll 2 is combined with the fixed scroll 1 as shown in the figure, and performs rotational movement, that is, oscillation, without changing its attitude in space. Figure 1(a).

(b) I (e) 0', 90° shown in I (d)
, 180': 270° operating position. As the swinging scroll 2 swings, 1. ";] The crescent-shaped compression chamber 4 formed between the spirals of the fixed scroll 1 and the oscillating scroll 2 gradually reduces its volume, and the gas taken into the compression chamber 4 is compressed and discharged from the discharge port 3. During this time, the distance oo between the centers O and O' in Figure 1 is kept constant, and if the spiral spacing is r1 and the thickness is t, then oo
'=7-t. r corresponds to the pitch of the spiral.

The outline of the device known by the name of scroll compressor is as follows.
It is conventionally known from, for example, No. 994,636.

Next, conventional technology related to this invention will be explained.

This conventional technique can be referred to, for example, in Japanese Patent Laid-Open No. 129791/1983, and the principle of the conventional technique is shown in FIGS. 2 and 3. In these figures, 2 is an oscillating scroll, 5 is a plywood tear of the oscillating scroll 2, and an oscillating scroll shaft 8 is provided protruding from the center of the base plate 5. The eccentric hole 7 formed in the six-piece balance weight 9 is a bearing fitted into the eccentric hole 6. The oscillating scroll shaft 8 is rotatably fitted into the bearing 1, and the base plate 5 is supported by a balance weight 9 which also serves as a driven link.

Reference numeral 10 denotes a drive shaft driven by a drive source (not shown) such as an electric motor, and a steady rest pin 12 is provided on the center of the large diameter portion of the drive shaft 1o, and a driven IJ link pin 11 is provided on the outer peripheral portion of the drive shaft 1o.
are respectively provided, and the lano pins 12 and 11 are fitted into the steady rest pin hole 14 and the driven link pin hole 13 provided in the balance weight 9, respectively. In addition, in FIG. 3, 0 is the rotation center that coincides with the center of the fixed scroll and the drive shaft 1o, oI is the center of the oscillating scroll 2, that is, the eccentric center, oI is the center of the driven link pin 11, r is the radial direction, and F θ is the angle between the eccentric center σ and the center σ of the driven link pin 11, and arrow A indicates the rotation direction.

Next, the operation will be explained. A balance weight 9 fitted to the drive shaft 1o and an oscillating scroll 2 fitted thereto
is driven via a drive shaft 1° by a drive source (not shown). The oscillating scroll 2 is shown in Fig. 1 (a), (b) t
(c) t The movement shown in (d) is performed, and when this movement is performed, a gas compression load and a centrifugal force act on the oscillating scroll 2. In the conventional example shown in FIGS. 2 and 3, the balance weight 9 and the swinging scroll 2 are integrally fitted to the drive shaft 10, so the balance weight 9 and the swinging scroll are integrated. 2 becomes a load F perpendicular to the radial direction r, as shown in FIG. That is,
The force in the radial direction r is applied to the center of the drive shaft 10, that is, the center of rotation 0.
It is constructed so that it cancels out when viewed from the outside. By the way, as shown in FIG. 3, the driven link pin 11 is located at a different position by an angle θ with respect to the center of the eccentric hole 6, that is, the eccentric center 0', and is different from the direction of the load F by #'i. Therefore, this load F is at the center O' of the oscillating scroll 2.
is attempted to be pushed outward around the center d of the driven link pin 13. As a result, the link radius corresponding to 0-0' increases, and the radial sealing of the spirals of the fixed scroll 1 and the swinging scroll 2 shown in FIG. 1 is realized.

Then, the radial sealing force is determined by the geometric relationship F'
It is known that tanθ. Furthermore, since the balance weight 9 is rotatable around the center 0' of the driven link pin 11, the steady rest pin 12 of the drive shaft 10 has an appropriate gap in the steady rest pin hole 14 for steady rest. By being fitted, free rotation around the driven link pin 11 is restricted.

Although the device constructed as described above was excellent as a practical radial sealing device for a scroll compressor, it had the following drawbacks. In other words, the balance weight 9 and the swinging scroll 2 must be constructed integrally, and the large balance weight 9 does not provide sufficient space for supporting the back surface of the swinging scroll 2 with a thrust bearing, and the radial sealing is not sufficient. Since the force is proportional to the load F, there is a serious drawback that the radial sealing force becomes unnecessarily large under high load conditions or liquid back conditions of a refrigerator.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and is designed to apply a component of the resultant force of the gas compression load and centrifugal force acting on the oscillating scroll to the radial sealing force of the vortex. It is an object of the present invention to provide a scroll compressor in which there is no need to attach a balance weight directly to the oscillating scroll, and in which the radial sealing force does not become excessive even when operating under moderate load conditions.

Before describing embodiments of the present invention, a scroll compressor having a structure in which a balance weight is not combined with an oscillating scroll will be described with reference to FIGS. 4 and 5.

In FIGS. 4 and 5, 2 is an oscillating scroll;
The oscillating scroll 2 includes a base plate 5 on which an oscillating scroll shaft 8 is provided. 10 is a drive shaft, an eccentric hole 6 is formed in the large diameter part of this drive shaft 100, a bearing T is fitted into the eccentric hole 6, and the above-mentioned oscillating scroll shaft δ is fitted into this M bearing 7.
are rotatably fitted, and the base plate 5 is supported by the large diameter portion of the drive shaft. Also, 0 is the rotation center, o' is the eccentric center, F' is the radial force, F' is the load perpendicular to the radial direction,
F is a load that is a combination of F' and Fl.

In a scroll compressor as shown in FIGS. 4 and 5, both a load V mainly consisting of a gas compression load perpendicular to the radial direction and a radial force I mainly consisting of a centrifugal force due to the mass of the oscillating scroll 2 are applied. and these are combined to form the load F.

This invention attempts to obtain a spiral sealing force in the radial direction by using the component force of the load F, and one embodiment of this invention will be described with reference to FIGS. 6 and 7.

6 and 7, 2 is an oscillating scroll, 8 is an oscillating scroll shaft, 10 is a drive shaft, 11 is a driven link pin, and 18 is a driven link, and this driven link 18 is an oscillating scroll 2. and the drive shaft 10, the driven link pin 11 provided on the drive shaft 10 is fitted into the driven link pin hole 13 provided on the driven link 18, and the bearing 7 is inserted into the eccentric hole 6 provided on the driven link 18. An oscillating scroll shaft 8 provided on the base plate 5 of an oscillating scroll 20 is rotatably fitted into this bearing I. Further, the large diameter portion of the drive shaft 10 is rotatably fitted into the main bearing 15 fitted on the inner peripheral surface of the main bearing 16 on the fixed side, and protrudes onto the drive shaft 10 of the main shaft 15. The driven link 18 is attached to the extended portion 15a.
are fitted, and the amount of movement of the driven link 1B is restricted by the inner surface of the extension portion 158, so that the driven link 1B is prevented from swaying. By forming the outer diameter of the driven link 18 to be smaller than the outer diameter of the large diameter portion of the drive shaft 10, the bearing gap 19 between the extension portion 15a of the main bearing 15 and the driven link 18 is formed between the main bearing 15 and the drive shaft. It is formed larger than the bearing clearance of the shaft 10. moreover,
An oscillating scroll 20 base plate 5 is supported on a thrust bearing 1T provided on the upper surface of the main bearing nozzle 16.

The straight line connecting the center d of the driven link pin 11 and the eccentric center 0' makes an angle θ with the vector of the resultant force F of the radial force F' and the load F' perpendicular to this, as shown in FIG. The angle θ is several degrees to several tens of degrees from the vector of the resultant force F. Therefore, the resultant force F tends to rotate the eccentric center 0' around the center 0' of the driven link 11, and increases the distance between the centers 0 and 0' corresponding to the crank radius. Therefore, the spirals of the orbiting scroll 2 tend to come into contact with the fixed scroll in the radial direction, and a radial sealing force is obtained. In this case as well, the magnitude of the radial sealing force is F tan θ.

Note that the configuration and operation of this embodiment other than those described above are the same as those in the first
Since it is substantially the same as the conventional one shown in FIGS. 2 and 3, the explanation will be omitted.

As explained above, this invention can achieve radial sealing of the volute without integrating the balance weight and the oscillating scroll, so there is sufficient space for the thrust bearing to support the oscillating scroll. This is a great effect of the present invention, as this was extremely difficult with conventional methods. In addition, in this invention,
The balance of the entire structure is achieved by a balance weight provided separately from the driven link.

Moreover, unlike the conventional one, in this invention, when the load on the compressor becomes large, the radial direction turtle shown in FIG. The angle θ between 0′-d and the resultant force F shown in FIG. 7 becomes smaller as the load F′ increases, and the radial sealing force F tanθ
Rather, as the load F' increases,
Therefore, the radial sealing force is not unnecessarily excessive in the high load region of the compressor, and on the contrary, when an abnormally high load is applied, the radial sealing force becomes negative and the gas applied to the oscillating scroll is prevented. It has the effect of being able to unload compression loads and hydraulic loads.

Furthermore, in this invention, the outside diameter of the driven link is made smaller than the outside diameter of the drive shaft so that the driven link can be rested on the inner circumferential surface of the extension of the main bearing, which is not necessary in conventional systems. It is possible to omit the steady rest pin, etc., and it is also possible to easily adjust the bearing gap between the main bearing extension and the driven link.By setting this to an appropriate size, the vibration of the driven link can be reduced by the effect of the bearing gap mentioned above. It also has the effect of being able to easily attenuate the noise, allowing for low-noise operation.

[Brief explanation of drawings]

Figures 1 (a) and (b) t (e) l (d) are explanatory diagrams of the operating principle showing different operating positions of the scroll compressor, and Figure 2 is an example of a conventional scroll compressor. A partially longitudinal exploded front view showing the radial sealing device;
FIG. 3 is a plan view showing the main parts of the radial sealing device shown in FIG. 2, and FIG. 4 is a partially longitudinal exploded front view showing the oscillating scroll and the upper part of the drive shaft according to another embodiment of the conventional scroll compressor. 5 is a plan view of the drive shaft of FIG. 4, FIG. 6 is a partially longitudinal exploded front view showing a radial sealing device according to an embodiment of the scroll compressor of the present invention, and FIG. 7 is a plan view of the drive shaft of FIG. ■- in Figure 6
■It is a plan view taken along the line. 1... Fixed scroll, 2... Oscillating scroll, 3
...Discharge port, 4...Compression chamber, 6...Eccentric hole, 1.
...bearing, 8...oscillating scroll shaft, 10...drive shaft, 11...driven link, pin, 13...driven link pin hole, 15...main bearing, 15a...extension Part 1
6... Main bearing...Using, 18... Driven link,
19...Bearing clearance. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Makoto Kuzuno (and 1 other person) -2” Stomach (c,,) (d) Nodθ (C)・)・
2 Figure f 2'S jZl ゛A j・ 5[1

Claims (1)

[Claims] In a scroll compressor that includes a fixed scroll and an oscillating scroll that have spirals of the same shape and opposite winding directions and are combined with each other, the oscillating scroll and the drive that transmits the driving force to the oscillating scroll. A driven link of a driven link mechanism is interposed between the shaft and the driven link to obtain radial sealing of the spiral, and a driven link bin is used to transmit driving force from the drive shaft to the driven link.The gas compression load acting on the oscillating scroll is and the vector of the resultant force of the centrifugal force, and are arranged on a straight line so that the radial sealing force of the spiral is at an appropriate value, and the driven link is pivotally supported by the drive shaft. 1. A scroll compressor, characterized in that the scroll compressor is fitted to an extension part of a main bearing so as to be rested thereon, and a bearing clearance of the extension part is made larger than a bearing clearance of the main bearing.