JPS63259104A - Volumetric control device for scroll type hydraulic machine - Google Patents

Abstract

PURPOSE:To make consuming power smaller so as to allow into correspond to an exhaust air quantity through a simple constitution by providing a passage which the inlet side is connected through to a working space at the fixed scroll side, and providing the passage with a volumetric control valve. CONSTITUTION:A pair of passages 6, 7 and 8, 9 are provided on the end cover 26 of a fixed scroll 2, on a scroll hydraulic machine having respective end plate portions 1a, 2a and involute lap portions 1b, 2b integrally, and provided with turning and fixed scrolls 1, 2 in which the respective laps 1b, 2b are engaged to each other. A pair of the passages 6, 7 is provided to allow a theoretical air quantity to be changed, while a pair of the passages 8, 9 is provided to allow a volumetric ratio to be changed. A plunger 10 is inserted in the respective passages 6-9. Furthermore, the plunger 10 within the passages 6, 7 are pulled on the allow spaces 4, 5 to be connected to the suction side via the passages 6, 7, and thereby the suction volume of the spaces 4, 5 is reduced and air quantity is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a capacity control device for a scroll fluid machine.

[Conventional technology]

An example of a conventional scroll fluid machine is Japanese Patent Application Laid-Open No. 50-32
This structure is disclosed in Japanese Patent No. 512 and will be explained with reference to FIGS. 5 and 6.

The orbiting scroll 1 includes an end plate portion 1a and a wrap portion 1b standing upright on the end plate portion 1a. The wrap portion 1b is formed into an involute or a curve close to an involute, and has a uniform thickness t and a uniform height h.

The mirror plate portion 1a and the wrap portion 1b are usually integrated.

The fixed scroll 2 has exactly the same configuration as the orbiting scroll 1, and includes a discharge port 3 at the center of the end plate portion 2a.

The orbiting scroll 1 and the fixed scroll 2 each have a wrap portion i.
The winding end ends 1b' and 2b' of b and 2b are approximately 180 mm.
°It is fitted in a shifted state.

An orbiting scroll 1 is revolved in a counterclockwise direction with respect to a fixed scroll 2 around the center of the fixed scroll 2.

During the revolution, the orbiting scroll 1 is rotated clockwise around the center Om of the orbiting scroll 1 by the same angle as the revolution, so that the orbiting scroll 1 does not apparently rotate. By revolving the orbiting scroll 1 in this way,
The closed working space 4.5 is contracted to compress the gas and discharge it from the discharge boat 3.

[Problem to be solved by the invention]

In this way, in the scroll compressor, efforts are made to seal the contact area or the closest part between the fixed scroll 2 and the orbiting scroll 1, the drive mechanism of the orbiting scroll 1, and the removal of centrifugal force. Little consideration was given to changing the volume ratio.

Methods for adjusting the discharge air volume in other types of positive displacement rotary compressors that do not require suction and discharge valves such as scroll compressors, such as screw compressors, include (a) a method to throttle the suction volume, (b) a method on the discharge side. Known methods include (c) a method in which a part of the discharged gas is returned to the suction side by connecting the engine and the suction side; and (c) a method in which the rotation speed is varied.

However, in case (a), the decrease in power consumption is small compared to the decrease in discharge air volume, and in case (b), the amount of gas circulating in the compressor itself does not decrease at all, so power consumption hardly decreases. . In the case of (c), the power consumption also decreases in proportion to the decrease in the discharge air volume, but the rotation speed variable device becomes complicated.

As described above, conventionally, when controlling the capacity, it has not been possible to reduce the power consumption in proportion to the discharge air volume with a simple configuration.

An object of the present invention is to provide a capacity control device for a scroll fluid machine that has a simple configuration and can reduce power consumption in proportion to the discharge air volume.

[Means for solving problems]

The features of the present invention are achieved by providing a passage on the fixed scroll side that communicates the fluid inflow side with the working space, and providing a valve for capacity control in this passage.

[Effect]

With the above configuration, the passage is closed by the valve, and communication between the inflow side and the working space is cut off. As a result, even if the volume of the working space decreases due to the orbiting movement of the orbiting scroll, the fluid does not flow out from the working space to the inflow side through the passage, and the flow rate taken into the fluid machine, that is, the discharge air volume is maintained at the maximum.

The passage is opened by the valve, and the inflow side communicates with the working space. As a result, when the orbiting scroll orbits and the volume of the working space decreases, the fluid in the working space flows out through the passage to the inflow side, and the flow rate taken into the fluid machine, that is, the discharge air volume decreases.

In this way, the simple structure of installing a valve to open and close the passage in the passage provided on the fixed scroll side allows the fluid machine to take in a flow rate commensurate with the required discharge air volume, thereby reducing power consumption. It can be reduced in accordance with the discharge air volume.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

FIGS. 3 and 4 show an embodiment of the present invention. In both figures, the same or equivalent parts are given the same reference numerals as those used in Figs. 1 and 2.
Explanation will be omitted.

A plunger 1o is fitted into a pair of passages 6, 7 and 6, 7 in which a pair of passages 6, 7 and 8, 9 are provided in the end plate portion 2b of the fixed scroll 2. The passages 6 and 7 and the passages 8 and 9 are arranged symmetrically with respect to the center Of of the scroll 2. A ring 11 is interposed between the end plate 2a and the plunger 10 to prevent gas leakage from between the end plate 2a and the plunger 10.

The pair of passages 6 and 7 are for changing the theoretical suction air volume, and the pair of passages 8 and 9 are for changing the volume ratio.

The passage 6 bypasses the gas in the space 4 where the orbiting scroll 1 is located on the outside and the fixed scroll 2 is located on the inside to the suction side, and is located near the outer peripheral surface of the wrap portion 2b of the fixed scroll 2. It extends outward from
The length Ω6 is such that it always protrudes from the outer peripheral surface of the wrap portion 2b of the orbiting scroll 1.

The passage 7 bypasses the gas in the space S where the fixed scroll 2 is located on the outside and the orbiting scroll 1 is located on the inside to the suction side, and crosses the lap part 2b of the fixed scroll 2 and passes through the lap part. It protrudes inside and outside of 2b.

However, the length of the passage extending inside the wrap portion 2b of the fixed scroll 2 is smaller than the thickness of the wrap so that the suction side does not communicate with anything other than the space 5.

Next, the operation of this embodiment will be explained.

When the orbiting scroll 1 is rotated with the passages 6, 7, 8.9 sealed by the plunger 10, the operation is similar to that in the conventional case (in the case of FIGS. 5 and 6).

When the orbiting scroll 1 is rotated while the plunger 10 fitted in the passages 6 and 7 is pulled in the direction of the arrow, the space 4 is connected to the suction side via the passage 6, and the space 5 is connected to the suction side via the passage 7. The state is the wrap part 2b of the fixed scroll 2.
and the outer contact line 1 with the lap portion 1b of the orbiting scroll 1
2.13 is continued until the installation position of the passages 6, 7 is reached, after which the spaces 4, 5 are sealed.

At this time, the volumes of the spaces 4 and 5 become the suction volume, and the passages 6,
Compared to when the space 7 is sealed by the plunger 10, the volumes of the spaces 4 and 5 are reduced and the air volume is reduced. Further, to explain this point using FIG. 4, when the passages 6 and 7 are closed, the suction amount is V and the pressure is a − + b −
+ P d, and the compression power corresponds to the area surrounded by Ps, a, b, and Pd. Next, if you want to reduce the capacity, by connecting one passage 6゜7 to the suction side, a
→The fluid with a volume of C is bypassed to the suction side through the passage, and the volume when suction is completed becomes Vs□. Also, the pressure is 0
-4d 41) 4 P d and the 5 compression power is P
This is the area surrounded by S, C2d, b, and Pd. Therefore, the power corresponding to the area surrounded by a, b, d, and c can be reduced. That is, the compression power can be reduced in accordance with the intake amount.

FIG. 3 shows another embodiment of the invention.

In this embodiment, passages 6, 7, 8.9 are provided across the end plate portion 2a and wrap portion 2b of the fixed scroll 2.

The other configurations and operations are the same as those of the above-described embodiments, so their description will be omitted.

In each of the above embodiments, a pair of passages 6 and 7 are provided to change the amount of suction, but it is also possible to provide a plurality of pairs to change the amount of suction in stages.

According to the above embodiment, the discharge air volume, that is, the capacity can be controlled with a simple configuration.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a capacity control device for a scroll fluid machine that can reduce power consumption in accordance with the discharge air volume with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of one embodiment of the invention. Fig. 2 is a sectional view taken along line nn in Fig. 1, Fig. 3 is a sectional view of another embodiment of the present invention, Fig. 4 is a diagram showing the relationship between the volume and pressure of the working space, and Fig. 5 is a conventional FIG. 6 is a front sectional view of the scroll compressor shown in FIG. 1...Orbiting scroll, 2...Fixed scroll, la, 2a...End plate portion, lb, 2b...Wrap portion. 3...Discharge port, 4,5...Space, 6,7,
8゜9...passage, 10...plunger. 4N week person age 1k +l-Toki Takagai Gosho) 1-1-winter゛- ;? , 7 Figure 676, q Fishing 10- Planshi Atsushi 2 Figure 3 Figure/θ

Claims (1)

[Claims] 1. A fixed scroll and an orbiting scroll each having an end plate part and a spiral-shaped lap part standing upright thereon are engaged with each other at the lap parts, and a plurality of working spaces are formed between both scrolls. In a scroll fluid machine that rotates so as not to apparently rotate relative to a fixed scroll and takes fluid into a working space from an inflow side and discharges it from an outlet, a passage communicating between the inflow side and the working space is provided on the fixed scroll side. A capacity control device for a scroll fluid machine, characterized in that a valve for capacity control is provided for the passage.