JPH0452399B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a scroll compressor used in a refrigeration cycle or the like, and more particularly to a thrust support device for a scroll that performs an orbiting motion.

Conventional configuration and its problems The conventional configuration will be explained with reference to FIGS. 4 and 5. 1
2 is a sealed casing, 2 is an electric motor section, and a mechanical section main body 7 consisting of a block 3, a fixed scroll 4, an orbiting scroll 5, and an anti-rotation mechanism 6 is fixed to the upper part of the motor section. The fixed scroll 4 is
It consists of an end plate 4a and an involute standing upright on the end plate 4a, or a flap 4b having a uniform thickness and a curve similar to an involute, and is fixed to the block 3 by the end plate 4a. The orbiting scroll 5 is composed of an end plate 5a and a lap 5b standing upright on the end plate 5a and having the same curve as the wrap 4b of the fixed scroll 4, and the end plate 5a is provided with a clearance A between the end plate 4a of the fixed scroll 4 and the block 3. The anti-rotation mechanism 6 is sandwiched and supported.
is restricted by. The fixed scroll 4 and the orbiting scroll 5 are aligned with the end ends 4b' and 5b' of each wrap 4b and 5b shifted by a certain angle.

8 is a discharge hole, and 9 is a suction hole. The discharge hole 8 is provided at the center of the involute of the fixed scroll 4, and the suction hole 9 is provided at the outer edge of the end plate 4a of the involute of the fixed scroll 4. Reference numeral 10 denotes a protrusion provided on the surface of the orbiting scroll 5 opposite to the wrap 5b, and is concentric with the center of the involute of the wrap 5b. Reference numeral 11 denotes a shaft supported by the block 3 via a thrust bearing 12, and an orbiting scroll 5 is attached to a boss portion 11a provided at the end of the seven main bodies of the machine section and eccentric from the center of the shaft.
The electric motor section 2 and the orbiting scroll 5 are connected by housing the protrusion 10 therein. In addition, an oil supply hole 11b penetrates through the center of the shaft 11,
Boss portion 11a of shaft 11 and orbiting scroll 5
The oil reservoir space 13 formed by the protrusion 10 communicates with the lower part of the sealed casing 1. 14 is a back pressure chamber formed on the back surface of the orbiting scroll 5, and the lap 5b side of the orbiting scroll 5 is the end plate 5.
It communicates with the low pressure part through the clearance A of parts a and 4a. 15 is a suction pipe communicating with the suction hole 9; 16
1 is a discharge pipe, and 17 is lubricating oil collected at the lower end of the sealed casing 1.

Next, the compression mechanism of the scroll compressor will be explained. The rotational movement of the shaft 11 accompanying the rotation of the electric motor section 2 is transmitted to the orbiting scroll 5 via the boss section 11a and the projection section 10, but the rotation prevention mechanism 6
Due to this action, the orbiting scroll 5 rotates around the center of the involute of the fixed scroll 4 without rotating. At this time, the end 5b' of the wrap 5b of the orbiting scroll 5 is the wrap 4b of the fixed scroll 4, and the end 4b' of the wrap 4b of the fixed scroll 4 is the end 5b' of the wrap 5b of the fixed scroll 4.
Inhalation is complete when the wraps 5b are in contact with each other, and as the two contact points of the wraps 4b and 5b approach the center of the involute as the orbiting scroll 5 revolves, the pressure in the compression gap S increases. .

By the compression mechanism of this scroll compressor, the refrigerant sucked from the suction pipe 15 through the suction hole 9 is compressed and once discharged into the sealed casing 1 through the discharge hole 8, and then cooled through the discharge pipe 16. system (not shown). At this time, as the pressure in the compression space S increases, a thrust force is generated between the fixed scroll 4 and the orbiting scroll 5 that tends to separate them in the axial direction. If the fixed and orbiting scrolls 4 and 5 are separated by this thrust force, the seals on the axial end faces of the wraps 4b and 5b in contact with the end plates 4a and 5a will be incomplete, increasing leakage and reducing efficiency. Therefore, conventionally, low pressure is introduced into the back pressure chamber 14 on the back surface of the orbiting scroll 5 through the clearance A, and high-pressure lubricating oil in the sealed casing 1 is introduced into the oil sump space 13 through the oil supply hole 11b of the shaft 11. was introduced into the orbiting scroll 5 to apply a pressing force to the orbiting scroll 5 that was greater than the thrust force caused by the compressed gas. That is, if the total area of the end plate 5a of the orbiting scroll 5 is circle A, the area of the protrusion is A ₁ , the high pressure is P _H , and the low pressure is P _L , then F=P _H ×A ₁ +
The pressing force of P _L ×(A−A ₁ ) was adjusted to be greater than the thrust force caused by the compressed gas. Further, the reaction force of the pressing force F is supported by the thrust bearing 12.

However, with this method, in order to maintain a pressing force greater than the thrust force of the compressed gas under any operating conditions, the area _A1 of the protrusion 10 must be increased, and the compressor must be increased in size due to the increased diameter of the rotation prevention mechanism. There was a problem related to formalization.

Purpose of the Invention The present invention eliminates the drawbacks of the above-mentioned conventional examples, and is capable of supporting the thrust force acting on the orbiting scroll under any operating conditions, and also enables the anti-rotation mechanism to be independent of the above-mentioned thrust force support mechanism. It is possible to downsize the compressor, which in turn allows the compressor to be downsized.

Structure of the Invention The present invention includes a rotating plate that is movable in the height direction of the wrap on the end plate of an orbiting scroll, and high pressure lubricating oil or gas is introduced between the end plate and the rotating plate to maintain thrust force and to rotate the scroll. By connecting the plate to the rotation prevention mechanism, the rotation prevention mechanism and the compressor can be made smaller.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1, 2, and 3.

Note that the same parts as those in the conventional example are given the same reference numerals and detailed explanations will be omitted.

Reference numeral 17 denotes an orbiting scroll, which has a lap 17b having the same shape as the conventional scroll and standing upright on an end plate 17a. 1
8 is a rotating plate, and the end plate 1 of the rotating scroll 17
7a and keys 19a, 19b, 19c, and 19d in the radial and circumferential directions, but it is movable in the height direction of the lap 17b. The rotating plate 18 is connected to the shaft 11 via a protrusion 20, and is also connected to the storage groove 21 of the rotation prevention mechanism 6.
a and 21b are provided on the protrusion 20 side. Further, a space 22 is formed between the rotating plate 18 and the mirror plate 17a,
By fitting the end plate 17a and the rotating plate 18, the space 22 is separated and sealed from the back pressure chamber 14, and the space 22 is communicated with the oil reservoir space 13 via the communication hole 23.

Further, the upper surface 11c of the shaft 11 and the rotating plate 18 are in contact with each other, and the shaft 11 is connected to the thrust bearing 1.
2.

In the above configuration, the mechanical part main body 7 is operated by the rotation of the electric motor part 2, and the refrigerant gas sucked in through the suction hole 9 as in the conventional case is compressed in the compression space S, and the refrigerant gas is compressed in the compression space S. After that, it is discharged from the discharge pipe 16 to a cooling system (not shown).

Then, low pressure is introduced into the back pressure chamber 14 as in the conventional case, and the oil supply hole 11b and oil sump space 1
3. High-pressure lubricating oil is introduced into the space 13 through the communication hole 23. As a result, the pressing force F that acts on the thrust force due to the compressed gas is F=P _H ×A ₁ +P _L where the area A of the end plate 17a, the area A ₁ of the space 22, the high pressure P _H , and the low pressure P _L ×(A-A ₁ ), and the reaction force of the pressing force F is held by the thrust bearing via the contact portion between the shaft tip 11c and the rotating plate 18. Therefore, by optimizing the area _A1 of the space 22, the pressing force F can be reduced in any operating state.
The compressor can be easily set so that it is larger than the thrust force, and the compressor can be operated efficiently. Also, unlike the conventional case, the shape and dimensions of the rotation prevention mechanism 6 are
Since it can be set independently of the space 22, the rotation prevention mechanism 6 can be optimized and the compressor can be downsized.

Effects of the Invention As is clear from the above description, the present invention comprises two mutually interlocking orbiting scrolls and fixed scrolls each having a lap that stands upright on an end plate, and an orbiting plate that is attached to the orbiting scroll and is movable only in the height direction of the lap. , an anti-rotation mechanism that prevents rotation of the orbiting scroll through the orbiting plate and allows the orbiting movement to occur, and a space formed between the back surface of the orbiting scroll on the opposite side of the lap and the orbiting plate, and the space communicates with the high-pressure part. The area of the space can be easily set to maintain a pressing force greater than the thrust force of the compressed gas under any operating pressure conditions, enabling efficient operation and preventing rotation regardless of the area of the space. It is possible to optimize the size and shape of the mechanism, and it is also possible to downsize the compressor.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of a scroll compressor showing an embodiment of the present invention, Fig. 2 is an enlarged cross-sectional view of the orbiting scroll and rotating plate shown in Fig. 1, and Fig. 3 is -' of Fig. 2. 4 is a vertical sectional view showing a conventional scroll type compressor, and FIG. 5 is a sectional view taken along line -' in FIG. 4. 4... Fixed scroll, 4a... End plate of fixed scroll, 4b... Wrap of fixed scroll, 6... Autorotation prevention mechanism, 17... Orbiting scroll, 17a... End plate of orbiting scroll, 17b... Wrap of orbiting scroll, 18... Rotating plate, 22 ...Space, 23...Communication section.

Claims (1)

[Claims] 1 two mutually interlocking orbiting scrolls and fixed scrolls having laps standing upright on end plates;
A rotating plate attached to the orbiting scroll and movable only in the height direction of the lap; an anti-rotation mechanism that prevents rotation of the orbiting scroll through the rotating plate and allows the orbiting scroll to perform an orbiting motion; A scroll compressor comprising a space formed between the wrap side back surface and the rotating plate, and a communication passage communicating the space with a high pressure section.