JPH0134314B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a multi-cylinder rolling piston type rotary compressor constituting a refrigeration cycle.

Conventional structure and problems thereof Conventionally, this type of multi-cylinder rolling piston rotary compressor has a motor element 102 inside a closed container 101 and a motor element 102, as shown in FIGS. 1 to 3. Compressor elements 103 and 104 driven by
3, 104, cylinders 105, 106, rotated by the motor element 102 and eccentric part 10;
7, 108 and this eccentric part 10
7, 108, the eccentric part 1 of the shaft 109
Rolling pistons (hereinafter simply referred to as pistons) 110, 11 eccentrically rotated by 07, 108
1, vanes 112, 113 that are inserted into grooves formed in the cylinders 105, 106 and slidably come and go to partition the compression chamber and the suction chamber; and the vanes 112, 113 are pressed against the pistons 110, 111. Elastic bodies 114 and 115, suction holes 116 and 117 for introducing and discharging refrigerant, and discharge holes 118 and 1
19, and discharge valve devices 120, 121 for opening and closing the discharge holes 118, 119, and end plates 122, 123 that cover the compressor elements 103, 104 and have bearings. . Further, an intermediate partition plate 12 is provided between the compressor elements 103 and 104 to partition the compressor elements 103 and 104.
4, both end plates 122, 123, cylinder 1
05, 106, it was constructed by bolts 125 that fasten the intermediate partition plate 124.

However, in this configuration, the intermediate partition plate 124 must be disposed between the two eccentric parts 107 and 108, and it is extremely difficult to simultaneously ensure sealing performance and ease of assembly, especially for three or more cylinders. , a method has been adopted in which the intermediate partition plate is divided into two parts.

OBJECT OF THE INVENTION The present invention eliminates the above-mentioned conventional drawbacks.
The purpose is to facilitate assembly.

Structure of the Invention In order to achieve this object, the present invention has an eccentric part of the shaft having a length spanning each compressor element, and furthermore, the eccentric part has the same eccentric direction, the same amount of eccentricity, and the same outer diameter, and each compressor element The inner diameter of the cylinder and the outer diameter of the rolling piston are made to be different diameters, and the partition walls of the adjacent compression elements are formed by closely contacting the side surfaces of each rolling piston, and the openings of both cylinders are formed in the end plate having the bearing part. It was then sealed.

With this configuration, an intermediate partition plate can be eliminated, and three or more compressor elements can be coaxially driven.

DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of the present invention will be described using a two-cylinder compressor as an example with reference to FIGS. 4 and 5.

First, the schematic structure of a two-cylinder compressor will be explained with reference to FIG.

In the figure, reference numeral 1 denotes a closed container, inside which is a motor element 4 consisting of a rotor 2 and a stator 3, and first and second compressors driven by the motor element 4 via a crankshaft 5. Elements 6 and 7 are arranged. The first and second compressor elements 6 and 7 are
First and second rolling pistons (hereinafter simply referred to as pistons) 9, 10 rotatably inserted into the eccentric portion 8 of the crankshaft 5, respectively;
A cylindrical first housing the second pistons 9 and 10;
It is composed of second cylinders 11 and 12 and upper and lower bearing end plates 13 and 14 that close openings at both ends of the first and second cylinders 11 and 12. These upper and lower bearing end plates 13 and 14 each form a pair,
It also serves as bearing support for the crankshaft 5. 15
are bolts that fasten the first and second cylinders 11, 12 and the upper and lower end plates 13, 14. 1
6 and 17 are the first and second cylinders 11 and 12;
The first and second suction holes are formed in the first and second suction holes.
suction pipes 18 and 19 are connected. A discharge pipe 20 is welded and fixed to the closed container 1 together with the first and second suction pipes 18 and 19.

Next, the configurations of the first and second compressor elements will be explained with reference to FIG. 5.

In the figure, the first compressor element 6 includes an end plate 13,
The second compressor element 7 is composed of the inner circumferential surface 11c of the first cylinder 11 and the outer circumferential surface 9c of the first piston 9, and the second compressor element 7 is composed of the end plate 14 and the second cylinder 12.
The inner peripheral surface 12c of the second piston 10 and the outer peripheral surface 1 of the second piston 10
It is composed of 0c. The partition at the center of the first and second compressor elements 6 and 7 is divided into an end surface 9p of the first piston 9 and an end surface 1 of the second cylinder 12.
2p and the end surface 10p of the second piston 10 are brought into contact with each other. Note that a vane (not shown) is provided in each of the first and second cylinders 11 and 12 so as to be freely retractable. As is well known, this vane is urged by an elastic body so as to come into contact with the piston.

Next, the dimensional relationship of each member will be explained with reference to FIG.

In the same figure, the inner diameter of the first cylinder 11 is
Dc, the height is H ₁ , the outer diameter of the first piston 9 is Dp ₁ ,
The inner diameter of the second cylinder 12 is Dc ₂ , the height is H ₂ , the outer diameter of the second piston 10 is Dp ₂ , the minimum sealing length between the first piston 9 and the second cylinder 12 is a,
Let Es be the amount of eccentricity of the eccentric portion 8 of the shaft 5. Here, the heights of the first and second pistons 9 and 10 and the heights of each vane (not shown) are approximated to the heights H ₁ and H ₂ of the first and second cylinders 11 and 12. There is.

Therefore, the inner diameter _Dc2 of the second cylinder 12 and the outer diameter _Dp2 of the second piston 10 are _Dc2 = _Dp1-2 (a+Es)...(1) _Dp2 = _Dp1-2 (a+2Es)... ...(2) It is expressed by the formula.

The above equations (1) and (2) are obtained as follows.

In Figure 6, since it is a rolling piston type, (A): Dc ₁ = Dp ₁ + 2Es (B): Dc ₂ = Dp ₂ + 2Es Also, in Figure 6' below (C): Z = Dc ₂ /2 + a = Dp ₁ /2-Es, that is, Dc ₂ = Dp ₁ -2 (a+Es)...(1) Also, from equations (b) and (1), (d): Dp ₂ +2Es = Dp ₁ -2 (a+Es), that is, Dp ₂ = Dp ₁ -2 (a + 2Es) ... (2) When the inner diameter Dc ₂ of the second cylinder 12 and the outer diameter Dp ₂ of the second piston 10 are given by the previous equations (1) and (2),
The end plate 13, the first cylinder 11, the first piston 9, the vane, the second cylinder 12, and the second piston 10 can constitute the first compressor element 6. Similarly, the end plate 14, the second
The second compressor element 7 can be constituted by the cylinder 12 , the second piston 10 , the second vane and the first piston 9 of the adjacent first compressor element 6 .

Next, the above description will be explained in detail with reference to FIG. 7.

In the figure, O is the axis of the shaft 5 and also the center of the inner diameter of the first and second cylinders 11 and 12. Further, O' is the axis of the eccentric portion 8 of the shaft 5, and is the center of the outer diameter and inner diameter of the first and second pistons 9, 10. In the figure, 11c indicates the inner circumferential surface of the first cylinder 11, 9c indicates the outer circumferential surface of the first piston 9, 12c indicates the inner circumferential surface of the second cylinder 12, and 10c indicates the inner circumferential surface of the second cylinder 12. piston 1
8c indicates the outer circumferential surface of the eccentric portion 8 of the shaft 5 and the inner circumferential surfaces of the first and second pistons 9 and 10.

Therefore, the inner circumferential surface 12c of the second cylinder 12 is aligned with the eccentric part axis O' with respect to the axis O of the shaft.
If the dimensions are set to ensure the minimum seal length a at the 180° position, the flat surface of the first piston 9 will be formed between the outer peripheral surfaces 9c and 8c of the first piston 9, and therefore the flat surface of the first piston 9 will be between 9c and 12c at any rotational position. In the radial direction a~
A sealing surface of 1/2 (Dc ₁ −Dc ₂ ) can be secured. Thereby, the first compression mechanism chamber A can be configured. On the other hand, the flat surface of the first piston 9 is formed between 9c and 8c, and the end surface of the second compression mechanism chamber B is formed between 12c and 10c at any rotational position.
However, since 12c always ensures the minimum seal length a and is located on the axis O side of the shaft of 9c, the end surface of the second compression mechanism chamber B is always the flat surface of the first piston 9. Ensures a sealing surface. This allows the second
The compression mechanism chamber B can be formed.

Next, the displacement volume of the first compressor element 6 is V ₁ ,
If the displacement volume of the second compression mechanism element 7 is V ₂ , then V ₁ = πEs (Dp ₁ + Es)・H ₁ ...(3) V ₂ = H ₂ /H ₁・V ₁ −2πEs・( a+2Es)・H ₂ ...(4) V ₁ +V ₂ =πEs {(Dp ₁ +E ₃ )(H ₁ +H ₂ ) −2(a+2Es)・H ₂ } ...(5) holds true.

Note that the above equations (3), (4), and (5) are obtained as follows.

V ₁ = π/4 (Dc ₁ ² - Dp ₁ ² )・H ₁ = π/4 (Dc ₁ + Dp ₁ ) (Dc ₁ − Dp ₁ )・H ₁ ... (a) Also, it is a rolling piston type. From Dc ₁ = Dp ₁ + 2Es ... (B) ∴Dc ₁ - Dp ₁ = 2Es ... (C) Also, from (B) (if you add Dp ₁ to both sides of (B)) Dc ₁ + Dp ₁ = 2 (Dp ₁ + Es) ...(d) Substitute (c) and (d) into (a) and get V ₁ = π/4・2 (Dp ₁ + Es)・2Es・H ₁ = π・Es (Dp ₁ +Es)・H ₁ …(3) In the same way as above, V ₂ =π・Es・(Dp ₂ +Es)・H ₂ …(4) Substituting equation (2), V ₂ =π・Es{ Dp ₁ −2(a+2Es)+Es}・H ₂ =π・Es {(Dp ₁ +Es)−2(a+2Es)}・H ₂ =π・Es・(Dp ₁ +Es)・H ₂ −2π・Es(a+
2Es)・H ₂ ...(E) From equation (3), V ₁ /H ₁ =π・Es・(Dp ₁ +Es) ...(F) Substituting (F) into (E), V ₂ = H ₂ /H ₁・V ₁ −2πEs (a+2Es)・H ₂ ...(4) V ₁ +V ₂ =V ₁ +H ₂ /H ₁・V ₁ −2πEs (a+2Es)・H ₂ = (H ₁ +H ₂ ) V ₁ /H ₁ −2πEs (a+ 2Es)・H ₂ ...(G) Also, from equation (3), V ₁ /H ₁ = πEs (Dp ₁ +Es) ...(4) Transform (H) into (G) Substitute V ₁ + V ₂ = (H ₁ + H ₂ )・πEs (Dp ₁ + Es) −2πEs (a+2Es)・H ₂ = π・Es {(Dp ₁ + Es) (H ₁ + H ₂ ) −2・(a+2Es ) H ₂ } ...(5) As shown in Fig. 8, the above relationship is as follows:
First and second suction holes 16, 1 for introducing suction gas
7 is provided with discharge valves (not shown) corresponding to the first and second compression mechanism chambers A and B, and first and second on-off valves 21 that open and close the suction holes 16 and 17;
22, the first on-off valve 21 is opened, and the second on-off valve 21 is opened.
By closing the on-off valve 22, a displacement volume V ₁ of the first compression mechanism chamber A is obtained, and by closing the first on-off valve 21, the second on-off valve 2 is closed.
By opening 2, the displacement volume V ₂ of the second compression mechanism chamber B is obtained, and by opening both the first and second on-off valves 21 and 22,
Displacement volume of the first and second compression mechanism chambers A and B
A displacement volume (V ₁ +V ₂ ) consisting of V ₁ and V ₂ is obtained, and basically three types of capacity variable control can be performed.

In this embodiment, two compression mechanisms are used, but even if three or more compression mechanisms are used, a multi-cylinder compressor can be constructed without the partition wall, and the volume can be varied over multiple stages. Alternatively, the drive device may be provided outside the closed container.

Effects of the Invention As explained above, according to the present invention, the partition plate between each compression mechanism can be eliminated, so assembly is extremely simple, and since the eccentric portion of the shaft is uniform, processing is extremely easy. It has advantages such as low cost and low cost.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional rolling piston rotary compressor, Fig. 2 is a plan sectional view of a compressor element in the same compressor, Fig. 3 is a longitudinal sectional view of the same compressor element, and Fig. 4 is an inventive invention. A vertical cross-sectional view of a rolling piston rotary compressor in one embodiment, FIG. 5 is a vertical cross-sectional view of a compressor element in the same compressor, and FIG. 6 is an explanatory diagram of the dimensional relationship of compressor elements in the same compressor. FIG. 7 is a sectional view taken along the line XX in FIG. 6, and FIG. 8 is a longitudinal sectional view of a rolling piston type rotary compressor showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Airtight container, 4... Electric motor element, 5... Crankshaft, 6... First compressor element, 7... Second
Compressor element, 8... Eccentric part, 9... First piston, 10... Second piston, 11... First cylinder, 12... Second cylinder, 13, 14
...Bearing end plate.

Claims (1)

[Claims] 1 A plurality of compressor elements driven by a drive element having an electric motor are disposed in the axial direction in a closed container, and each of the compressor elements is provided with a cylinder and an eccentric a rolling piston that is rotatably provided on the eccentric portion and rotates eccentrically within the cylinder together with the eccentric portion of the shaft; and a rolling piston that is slidably inserted into the cylinder and partitions a compression chamber and a suction chamber. A vane, an elastic body for pressing the vane against the rolling piston, a suction hole for introducing compressed refrigerant, a discharge hole for discharging the compressed refrigerant, and a discharge valve device for opening and closing the discharge hole, and A multi-cylinder rolling piston rotary compressor is configured by providing end plates having bearing portions for the shaft and fastening portions connecting the both end plates and the compressor element at both ends in the axial direction of each compressor element, The eccentric portion of the shaft has a length spanning each of the compressor elements, and the eccentric portion has the same eccentric direction, the same amount of eccentricity, and the same outer diameter, and the cylinder inner diameter and rolling piston outer diameter of each of the compression elements are different diameters. A rolling piston rotary compressor, further comprising partition walls of adjacent compression elements formed by closely adhering side surfaces of each rolling piston, and openings of both cylinders sealed by end plates having the bearings.