JPH05288169A - Scroll compressor - Google Patents

Abstract

PURPOSE:To prevent contraflow and suction interference onto the suction port side immediately before the completion of suction while preventing suction heating so as to improve the performance and capacity of a compressor. CONSTITUTION:A suction port 4 is opened near the suction and closing positions set in the same direction. A buffer space is then provided in the winding end extended direction of a turning scroll 2, and the suction port 4 is opened more onto the inner peripheral side than the winding end. A rectifying guide is further provided to perform smooth suction or the completion of suction is expedited about 50 deg. compared to the existing way so as to prevent contraflow. In this method, the suction port 4 and a suction chamber are isolated from each other by a blade or the like for connecting the outer winding end of a fixed scroll 1 to a circular arc part of the same radius as the turning radius.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor which is a kind of positive displacement compressor used in refrigerators, room air conditioners and the like.

[0002]

2. Description of the Related Art A conventional scroll compressor is disclosed in
This will be described with reference to FIG. 12 to FIG. 16 with reference to Japanese Patent Publication No. 20701. FIG. 12 is a vertical sectional view of a compression element portion of a conventional scroll compressor, and FIGS. 13 and 14 are plan views of a spiral portion showing a II cross section of FIG. The fixed scroll member 1 includes an end plate 1a and a spiral body 1b standing upright on the end plate 1a, and the orbiting scroll member 2 similarly has an end plate 2a and a spiral body 2.
b and a pin portion 2c protruding further to the back. As the spiral shape, an involute curve in which the spiral pitch and the thickness of the spiral wall are constant is generally used. A discharge port 3 is provided at the center of the end plate 1a of the fixed scroll member 1, and a suction port 4 is provided at the outer peripheral portion. The frame 5 is fixed to the outer peripheral portion of the end plate of the fixed scroll member 1 by bolts (not shown). The crankshaft 6 is supported by a bearing portion 7 provided on the frame 5. A balance weight 9 is formed on the crankshaft 6, and a boss hole 10 is formed on the head at a position eccentric from the shaft center O by a distance ε. The orbiting scroll pin portion 2c is fitted in the boss hole 10.
An Oldham ring 12 is used to prevent the orbiting scroll member 2 from rotating.

Both scroll members 1 and 2 are scrolls 1b and 2
At least one closed volume is formed on each of the outer side and the inner side of the orbiting scroll spiral body by intermeshing with b inside. The maximum volume of each closed case is formed by the spiral end 2b1, 2b2 of the orbiting scroll 2 and the spiral end 1b1, 1b2 of the fixed scroll 1 being in contact with each other and being closed. The closing positions 1b1 and 1b2 are set to be in the same direction in FIG. 14 where they are 180 ° apart from the center of the spiral in the state of FIG. 14
As described above, by shifting the closed position within 180 °, there is no wasted space in the outer peripheral portion, the suction volume is increased, and it is effective in downsizing. As another example of such miniaturization, there is JP-A-55-109792.

The crankshaft 6 is driven by an electric motor (not shown) or the like.
Is rotated clockwise, the orbiting scroll member 2 revolves clockwise relative to the fixed scroll member 1 without changing its posture (apparently not rotating). Figure 1
5, the closing position is shifted by 180 ° (corresponding to FIG. 14),
The state in which the orbiting scroll outer end 2b1 is in contact with the fixed scroll end 1b1 (Fig. (A) where 0 °) is revolved every 90 ° is shown in Figs. d). With the revolution, the contacts of both scrolls move to the inner circumference side. The fluid flowing into the outer peripheral portion from the port 4 is taken in between the scrolls of both scrolls,
Closed after 1 revolution from the start of intake, and closed volume V
1, V2 are formed. Furthermore, the closed volumes V1, V2
Reduces the volume toward the inner peripheral side, and the fluid is compressed and discharged from the discharge port 3. Further, in the case of FIG. 15, the two suction timings are shifted from each other by 180 °.

[0005]

The vertical axis represents the volume change of the suction volume V (similar to V ') taken into the suction chamber of the stippled portion shown in FIG. 15, and the vertical axis of the crankshaft from the time when both scroll ends are in contact. Taking the rotation angle on the horizontal axis, as shown in FIG. 16, the maximum volume V (V ′) is 50 ° before closing.
In the vicinity, the volume is about 105% of the closed volume. That is, the fluid once taken in between the scroll members flows back to the suction port side just before the fluid is closed. As a result, in the structure disclosed heretofore, due to the backflow of the fluid at the time of closing, it collides with the flow to the other opposing suction chamber during suction, and the flow is stagnated. In this way, the flow interferes and the suction is hindered, so that the volumetric efficiency of the compressor is lowered. To prevent this interference, a space is left between the suction port and the closed position to serve as a buffer.
Heat loss occurs between the suction port and the space between the scroll members, and it is insufficient to prevent suction interference.

An object of the present invention is to prevent suction heating and prevent suction interference due to backflow to the suction port side immediately before completion of suction, thereby improving the capacity and efficiency of the compressor.

[0007]

To achieve the above object, the present invention opens a suction port near a closed position of a scroll forming a suction chamber to extend a buffer space to a fixed scroll winding end portion. It is provided on the outer peripheral side from the suction port opening position in the direction. The opening of the suction port is provided on the inner peripheral side of the spiral scroll spiral end. At this time, in order to secure the suction opening area, the suction passage is extended and provided on the inner peripheral side of the fixed scroll spiral body. Further, the backflow interference is reduced by providing a guide for rectifying the suction fluid.

Alternatively, as a method for preventing the occurrence of the backflow itself, the communication between the suction space and the suction port may be cut off immediately before the orbiting scroll spiral ends 2b1 and 2b2 contact the spiral end 1b1 or 1b2 of the fixed scroll. .. In the case of the outer suction chamber of the orbiting scroll spiral body, the fixed scroll spiral end 1b1 is connected to an arc portion having the same radius as the revolution radius ε so that the arc portion and the orbiting scroll spiral end 2b1 are in smooth contact with each other. To isolate both suction chambers, a blade portion extending tangentially is provided at the end of the orbiting scroll.

[0009]

By opening the suction port close to the closed position, the heating loss of the fluid after entering the suction port is eliminated. The buffer space is provided on the outer peripheral side of the suction port opening position in the extension direction of the winding end portion of the fixed scroll spiral body, so that interference with the suction port side for supplying the fluid can be reduced. The center of the suction port is approximately on the center line of the groove width of the winding end portion of the fixed scroll spiral body, the opening width is equal to or smaller than the revolution diameter, and is located on the inner peripheral side of the winding end portion of the orbiting scroll spiral body. With such a configuration, the passage that directly flows back to the suction port side before closing is blocked by the scroll body of the orbiting scroll, and interference can be reduced. Similarly,
By providing the guide for rectifying the suction fluid, the interference with the suction stroke on the opposite side can be reduced.

If the suction chamber and the suction port are prevented from communicating with each other about 50 ° in revolution angle from the conventional closed position where both scroll ends are in contact with each other, theoretically, the reverse flow to the suction port side can be prevented. be able to. If the circular arc portion connected to the fixed scroll spiral end and the orbiting scroll spiral end are in contact with each other smoothly, the backflow of the outer suction chamber of the orbiting scroll spiral body can be prevented. The blade provided at the winding end portion of the orbiting scroll spiral body can block the communication between the suction port and the suction chamber to prevent backflow in both suction chambers.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. It should be noted that the measure against the backflow at the time of completion of suction is omitted when the other side has the same operation.

FIG. 1 is a plan view showing a suction port portion of a scroll compressor according to an embodiment of the present invention. In the figure, the suction port 4 is provided at a close position that does not reach the end of the orbiting scroll. Reference numeral 16 denotes a buffer space provided on the outer peripheral side of the opening position of the suction port 4 in the extension direction of the end of the orbiting scroll. In this case, the backward flow 15a flows into the buffer space 16, and the suction flow 15b with less interference can be secured.

FIG. 2 is a plan view showing the suction port portion of the scroll compressor according to the embodiment of the present invention. In the figure, the suction port 4 is an orbiting scroll spiral end 2b1.
Although it is provided on the inner peripheral side from (2b2), the center of the suction port is approximately on the center line of the groove width of the fixed scroll winding end portion, and the opening width is not more than the revolution diameter. This prevents the suction port and the suction chamber from directly communicating with each other even when the scroll scroll ends are in contact with each other. The reverse flow 15a reverses its direction at the end of the fixed scroll groove and becomes a flow in the same direction as the suction flow 15b, so that a frontal collision of the flow can be avoided. In this case, the opening area of the suction port is blocked by the orbiting scroll spiral body and becomes smaller.
The opening area can be secured by providing the suction passage groove 20 extending to the inner peripheral side as shown in a sectional view taken along the line III-III.

FIG. 4 is a plan view showing a suction port portion of a scroll compressor which is another embodiment of the present invention. The width of the fixed scroll spiral groove end is small and the suction port 4 is
When installed on the inner circumference side from the winding end of the orbiting scroll,
The suction port and the suction chamber may directly communicate with each other even when the scroll ends are in contact with each other. Assuming this case, the suction port 4 is provided at the winding end extension of the orbiting scroll.
And the rectification guide 17 are provided. A flow that does not interfere with the backflowed flow 15a in this case is shown as 15b.
In this case, a separate component is required as the rectification guide, but as shown in the plan view of the suction port portion of the scroll compressor shown in FIG. 5, the winding end of the orbiting scroll is extended and integrated with the orbiting scroll. A guide portion 2d can be provided.

FIG. 6 is a plan view showing a suction port portion of a scroll compressor which is another embodiment of the present invention. The arcuate portion 1c having the same radius as the revolution radius ε is smoothly connected to the outer spiral end 1b1 of the fixed scroll, and smoothly contacts the orbiting scroll spiral end 2b1.
The central angle θ of the arcuate portion is set to about 40 °, which separates the suction chamber and the suction port portion earlier than the conventional closed position. The reason why the angle of the arc portion is smaller than 50 ° is to maximize the amount of fluid actually taken into the suction chamber by ensuring the supercharging effect due to the inertia of the fluid itself and the suction passage area. In this way, the reverse flow of the fluid can be eliminated, and the actual suction amount (compressor capacity) can be increased. This timing is also common to other examples,
Most effective in blocking or closing the suction passage. It should be noted that the improvement of preventing the backflow on the outside of the orbiting scroll spiral by providing this arc portion can be configured by providing the escape portion in the orbiting scroll spiral body even if the suction closing position is shifted by 180 °. Yes, the effect of increasing compressor capacity is similar.

7 and 8 are plan views showing the suction port portion of the scroll compressor according to the sixth and seventh embodiments of the present invention. A blade 18 and a spring 19 are provided at the end of winding of the orbiting scroll, and the suction port 4 is provided so as not to communicate with the suction chamber before the conventional shut-off. Figure 7,
In FIG. 8, the blades are inserted into the groove portions 21 provided on the orbiting scroll and the fixed scroll, respectively. FIG. 9 shows FIG.
It is a longitudinal cross-sectional view of the blade portion of. Thereby, backflow can be prevented in both suction chambers. In the present embodiment, a spring was required, but if the blade 18 and the groove portion 1d provided in the fixed scroll are arranged as shown in FIG. 10, the spring can be omitted. The shape of the suction port is rectangular to ensure the passage area.

The spiral shape of the present invention is not limited to the involute curve. FIG. 11 is a plan view of a spiral portion of a scroll compressor according to another embodiment of the present invention. In this embodiment, the spiral is composed of a curve that smoothly expands and its envelope. Here, an example of an algebraic spiral is shown as a curve that smoothly extends. The algebraic spiral is expressed in polar coordinates (radial radius r, declination θ), and is represented by the following equation 1 using a and k as parameters (these may be functions of θ, etc.).

[0018]

[Equation 1]

The algebraic spiral and the envelope can be selected in various ways, but an algebraic spiral is selected for the inner curve of the spiral body, and the inner curve is rotated by 180 ° for the outer curve of the spiral body. This is the case when the inner one is selected from the two envelopes formed when the orbital motion is performed. By doing so, the spiral bodies of the orbiting and fixed scrolls can have the same shape, and the spiral body can be processed by one end mill having the same radius as the orbiting radius. Further, as shown in the drawing, a spiral body having an advantage that the top clearance volume at the center of the spiral can be easily made zero and re-expansion loss can be eliminated can be configured. By using such a spiral shape, it is possible to easily leave the circular arc portion as shown in FIG. 1 when processing the spiral body.

Further, with the number 1 of the algebraic spiral, for example, by setting the coefficient a to a constant and the index k to a constant of k <1.0, the spiral wall is thick in the central portion and thin in the outer peripheral portion. Securing the strength of the spiral body required due to the large pressure difference,
Effective in reducing internal leakage of fluid. Further, in order to obtain a spiral shape having the same ability and pressure ratio, it is possible to construct a spiral body having an advantage that the swirling radius can be increased while the diameter of the spiral body is smaller than that of the involute curve. By using such a spiral shape, even if the suction port is provided so as to overlap the orbiting scroll spiral body, since the suction port is less blocked, a scroll compressor with high volume efficiency can be obtained.

The above-mentioned embodiments are effective even if they are used independently, but by using them in combination, the effect of improving efficiency can be increased. Further, by using the scroll compressor of the present invention in a refrigeration / air conditioning system, a system having high efficiency and small vibration can be obtained.

[0022]

According to the present invention, by providing the suction port in the vicinity of the end of the spiral, it is possible to eliminate the suction heating loss of the fluid to be compressed and improve the efficiency of the scroll compressor. Further, by devising the closing timing of the suction chamber, it is possible to prevent the backflow of the fluid from the suction chamber, to make the supply of the fluid smooth, and to provide a scroll compressor with high volume efficiency. By installing such a scroll compressor in a refrigeration cycle, a refrigeration / air-conditioning system with excellent energy efficiency and small vibration can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of a scroll compressor suction port according to an embodiment of the present invention.

FIG. 2 is a plan view of a main portion of a scroll compressor suction port according to a second embodiment of the present invention.

FIG. 3 is a sectional view of the suction passage III-III in FIG.

FIG. 4 is a plan view of a main portion of a scroll compressor suction port according to a third embodiment of the present invention.

FIG. 5 is a plan view of an essential portion of a scroll compressor suction port according to a fourth embodiment of the present invention.

FIG. 6 is a plan view of an essential portion of a scroll compressor suction port according to a fifth embodiment of the present invention.

FIG. 7 is a plan view of an essential portion of a scroll compressor suction port according to a sixth embodiment of the present invention.

FIG. 8 is a plan view of an essential portion of a scroll compressor suction port according to a seventh embodiment of the present invention.

9 is a vertical cross-sectional view of the blade portion of FIG.

FIG. 10 is a plan view of an essential portion of a scroll compressor suction port according to an eighth embodiment of the present invention.

FIG. 11 is a plan view of a spiral portion of another scroll compressor according to the present invention.

FIG. 12 is a vertical cross-sectional view of a conventional scroll compressor.

FIG. 13 is a plan view of a spiral portion of a conventional scroll compressor.

FIG. 14 is a plan view of a spiral portion of a conventional scroll compressor.

FIG. 15 is an explanatory diagram of a compression principle of the scroll compressor.

FIG. 16 is an explanatory diagram of a volume change of a suction chamber of the scroll compressor.

[Explanation of symbols]

1 ... Fixed scroll, 2 ... Orbiting scroll, 3 ... Discharge port, 4 ... Suction port.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroshi Iwata Hiroshi Iwata 502 Jinritsucho, Tsuchiura-shi, Ibaraki Hiritsu Seisakusho Co., Ltd.Mechanical Research Laboratory (72) Inventor Kazuhiro Endo 502 Jinritsucho, Tsuchiura-shi, Ibaraki Hiritsu Seisakusho Co., Ltd. Inside the mechanical laboratory

Claims (1)

[Claims] 1. A fixed scroll having a spiral body and an orbiting scroll are brought into contact with each other to be engaged with each other, and the orbiting scroll is revolved with respect to the fixed scroll. A scroll compressor that closes off at two positions at the end of winding, forms a closed volume outside and inside the spiral body of the orbiting scroll, and moves toward the inner peripheral side as it revolves to reduce the volume and compress. In the above, the two closing positions are set in substantially the same direction from the center of the spiral, and a suction port for supplying a fluid to be compressed is formed in the vicinity of the closing position in the extension direction of the winding end portion of the fixed scroll spiral body. A scroll compressor having a buffer space on the outer peripheral side of the opening position of the suction port.