JPH0220836B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a scroll compressor installed in a refrigerator/air conditioner or the like.

BACKGROUND ART Recently, scroll compressors have been attracting attention as refrigeration compressors because of their high efficiency and low vibration and noise. First, the conventional operating principle of a scroll compressor will be explained with reference to FIGS. 1a to 1d.
Figure 1a shows the phase relationship between the movable wrap 1a and the fixed wrap 2a in a state where compression starts at the same time as suction is completed, and Figures 1b, 1c and 1d are the same as in Figure 1a. , shows a state in which the movable wrap 1a has been rotated 90 degrees counterclockwise from the state shown in FIGS. 1b and 1c. From the state of Figure 1a to Figure 1b and Figure 1c
As the state changes, the closed space 12 closed by both laps 1a and 2a decreases, the gas is compressed, and high-pressure gas is flowed from the discharge hole 3. Then, from the state shown in Fig. 1d, the movable lap 1a is further moved.
By turning 90 degrees, the original state, i.e. the first
Return to the state shown in Figure a. In FIGS. 1a to 1d, the closed space 12 is formed by the radial contacts 4 of the two laps 1a, 2a.

A cross section of a conventional scroll compressor based on the above operating principle will be explained with reference to FIG. 2 is the discharge hole 3
It is fixed to the housing 5 by a fixed scroll consisting of an end plate 2b provided with a spiral curve and a fixed side wrap 2a formed on the end plate 2b. Reference numeral 1 denotes a movable scroll, which is composed of an end plate 1b and a movable side wrap 1a of a spiral curve formed on the end plate 1b.This movable scroll 1 is rotatably supported via a bearing 7a of a frame 6 fixed to a housing 5. It is attached to the crank portion 8a of the shaft 8 via a bearing 7b, and is assembled so that the movable side lap 1a meshes with the stationary side lap 2a. 1
0 is a rotation prevention mechanism provided to prevent the movable scroll from rotating, and is fixedly attached to the frame 6. The shaft 8 has a stator 11 and a rotor 12
The movable wrap 1a is rotated relative to the fixed wrap 2a as shown in FIG. 1 by a motor section consisting of a motor section, thereby increasing the pressure of the gas in the closed space 12 and causing it to flow out from the discharge hole 3.

FIG. 3 shows an enlarged scroll view of the vicinity of the discharge hole 3 in FIG. 1. Conventionally, the position of the discharge hole 3, the movable side lap 1a and the fixed side lap 2a at the end of compression were
As yet, there has been no means to improve performance in relation to the positional relationship. That is, as shown in FIG. 3, before the spiral start tip A of the movable wrap 1a comes out of contact with the fixed wrap 2a, the discharge hole 3 is not inside the movable wrap 1a and the discharge hole 3 is already closed.
Because it communicates with the next sealed space 12', not only is the sealed space 12 not compressed, but the gas that has been compressed up until now flows into the sealed space 12', which has a lower pressure, as shown by the arrow. This had the disadvantage that the power required increased and the efficiency of the compressor decreased.

In particular, in a scroll compressor, as is clear from Fig. 1, the sealed spaces exist symmetrically, and the pressure inside each pair of sealed spaces is equal, but the discharge hole 3 communicates with only one sealed space. This creates a pressure difference with other sealed spaces, resulting in an abnormal bearing load, shortening the life of the compressor and causing power loss.

To solve the above problem, there is a method in which the discharge hole is made smaller than the lap width (for example, Japanese Patent Laid-Open No. 55-46081).

In addition, the discharge hole is configured to be larger than the wrap width, and the discharge hole is configured to be inside the inner circumferential edge of the movable wrap in the final compression state when the swirl starting tip of the movable wrap comes out of contact with the fixed wrap due to rotational movement. There are some examples (for example, JP-A-1983-
101788).

Problems to be Solved by the Invention However, in the former case, there is a problem in that if the discharge hole is made smaller, the flow resistance of the refrigerant gas increases and the performance of the compressor is significantly reduced.

On the other hand, in the latter case, the flow resistance of the refrigerant gas in the discharge hole can be reduced, and the compressed refrigerant gas will not flow back into the closed space where the pressure is low, but in the process after the refrigerant gas is discharged,
The problem is that extra compression must be done. In other words, after the refrigerant gas is discharged,
It is necessary to reduce the refrigerant pressure in the compression space communicating with the discharge hole as quickly as possible to eliminate excess compression, but this pressure balance can only be achieved from the tip of the movable lap where the swirl starts.

Therefore, the present invention reduces the flow resistance of refrigerant gas in the discharge hole by optimizing the size of the discharge hole and appropriately positioning the movable wrap and the fixed wrap. The purpose is to quickly balance the pressure between a compression space communicating with a discharge hole after refrigerant gas is discharged and a compression space adjacent to this compression space, thereby eliminating unnecessary compression action and power loss.

Means for Solving the Problems In order to achieve the above object, the present invention has a configuration in which the diameter of the discharge hole is larger than the width of the wrap, and the swirl starting tip of the movable wrap is rotated to connect with the fixed wrap. In the final compressed state where the contact is broken, the discharge hole enters inside the outer periphery of the movable wrap, and partially extends outside the inner periphery, so that there is a space between the discharge hole and the space outside the outer periphery of the movable wrap. is sealed between the movable side lap and the end plate of the fixed scroll.

Effect: With the above means, the diameter of the discharge hole can be increased, so that the flow resistance of the refrigerant gas in the discharge hole can be reduced.

In addition, in the final compression state, it is possible to seal between the discharge hole and the space outside the outer periphery of the movable wrap, so that the refrigerant in the sealed space formed by the movable wrap and the fixed wrap, including the discharge hole, is There will be less leakage into the space.

In addition, when the rotation has progressed even slightly from the final compression state, communication between the compression space communicating with the discharge hole and the adjacent compression space is not only from the tip of the teeth of the oscillating scroll, but also through the discharge hole. Since the compression is also performed through the discharge hole, the pressure balance between the compression space communicating with the discharge hole and the compression space adjacent to this compression space can be quickly achieved, and overcompression can be eliminated and power loss can be prevented.

Embodiment The structure and operation of the present invention will be explained below with reference to FIG. For convenience, the same functional parts as in FIGS. 1, 2, and 3 are given the same reference numerals.

The structural cross section of the scroll compressor of the present invention is the same as that shown in FIG. 2, and the operating principle is also the same as that shown in FIG. 1, but as shown in FIG. The positional relationship between the position and the discharge hole 3 is different from the conventional example.

That is, wraps 1a and 2a consisting of spiral curves
A movable scroll 1 formed on end plates 1b and 2b,
The fixed scrolls 2 are engaged with each other with the wraps 1a and 2a inside, and the movable scroll 1 is rotated relative to the fixed scroll 2 to create a plurality of closed spaces 12 and 12' closed by the wraps 1a and 2a of both scrolls. , 12''..., and causes the high-pressure gas to flow out from the discharge hole 3 provided approximately at the center of the end plate 2b on the fixed side, and the swirl starting tip A of the movable wrap 1a undergoes a rotating motion. Therefore, in the final compressed state in which contact with the stationary wrap 2a is lost, the discharge hole 3 is located inside the outer circumferential edge 1a _p of the movable wrap _1a as shown in FIG. The closed space 12 and the next closed spaces 12' and 12'' do not communicate with each other, because between the closed spaces 12 and 12', the area 13 surrounded by the dotted line in FIG. There is a gap of several microns between the end plate 2b of the fixed side lap and the movable side lap 1a, and the lubricating oil enters this gap and seals between the closed space 12 and the closed space 12'. be. As the turning movement progresses from this state, the spiral start tip A of the movable wrap 1a moves to the fixed wrap 2.
Since the contact with a is lost, the high pressure gas in the sealed space 12 flows from the swirl starting tip A to the next sealed space 1.
However, the high-pressure gas in the closed space 12 will not flow out to the next closed space 12' until this final state of compression is reached, that is, until the spiral tip A of the movable wrap 1a is removed from the fixed wrap 2a. If a predetermined compression ratio can be secured and the rotational movement progresses even slightly, the discharge hole 3 and the closed space 12' will communicate with each other, and the pressure will be balanced and an abnormal overpressure state will not occur.

Therefore, it is possible to provide an efficient scroll compressor with low top clearance and low power loss.

Furthermore, the diameter of the discharge hole 3 is the same as that of the movable side lap 1a.
Since the width of the refrigerant gas discharge hole 3 is made larger than the width of the refrigerant gas discharge hole 3, the flow resistance at the refrigerant gas discharge hole 3 can be reduced, and therefore the pressure loss can be reduced and the performance can be improved.

Effects of the Invention As is clear from the above description, according to the scroll compressor of the present invention, the discharge hole can be configured as large as possible, so that the flow resistance of the refrigerant gas at the discharge hole can be reduced, and therefore the pressure can be reduced. The loss is reduced and the performance of the compressor can be improved.

In addition, in the final compression state where the spiral start tip of the movable wrap comes out of contact with the fixed wrap due to the rotational movement, the discharge hole is configured to enter inside the outer circumferential edge of the movable wrap and partially protrude outward from the inner circumferential edge,
Since the discharge hole and the closed space formed from the discharge hole via the movable side lap are sealed, the closed space on one side does not communicate with the closed space on the discharge hole side, and the pressure is raised. It is possible to prevent power loss due to a rapid decrease in the amount of fuel, or conversely, the need for extra compression, allowing highly efficient compression at a predetermined compression ratio.

Furthermore, since it is possible to prevent a part of the sealed space from communicating, it is possible to prevent abnormal bearing loads caused by pressure imbalance, thereby extending the life of the compressor and improving efficiency. .

[Brief explanation of drawings]

Figures 1a, b, c, and d are positional relationship diagrams of the fixed and movable wraps, respectively, showing the operating principle of a scroll compressor. Figure 2 is a cross-sectional view of the main parts of a conventional scroll compressor. Figure 3 is a FIG. 4 is an enlarged view of the vicinity of the discharge hole of a conventional scroll compressor, and FIG. 4 is an enlarged view of the vicinity of the discharge hole of the scroll compressor of the present invention. 1... Movable scroll, 1a... Movable side lap, 2... Fixed scroll, 2a... Fixed side lap, 1b, 2b... End plate, 3... Discharge hole, 12,
12'... Closed space, A... Spiral start tip, 1a _p
...Outer periphery of the movable wrap, 1a _i ...Inner periphery of the movable wrap.

Claims (1)

[Claims] 1. A fixed scroll and a movable scroll, each having a spiral wrap formed on the end plate, are engaged with each other with the wraps inside, and the movable scroll is rotated relative to the fixed scroll to create a plurality of sealed spaces closed by the wraps of both scrolls. The high-pressure gas is sequentially pressurized and flows out from a discharge hole provided approximately in the center of the end plate on the fixed side, and the diameter of the discharge hole is configured to be larger than the lap width, and In the final compression state in which the swirl starting tip of the lap comes out of contact with the stationary lap due to the rotational movement, the discharge hole enters inside the outer circumferential edge of the movable wrap and partially protrudes outside the inner circumferential edge. A scroll compressor in which a space outside the outer peripheral edge of the wrap and the discharge hole is sealed by the movable wrap and the end plate of the fixed scroll.