JPS582490A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To prevent the compressed fluid from being reflated by forming the central ends of both stationary and movable volutes in a bulb shape and by providing a discharge hole connecting between a fluid pocket and a discharge valve chest at the bulb-shaped central end of the stationary volute on the side wall in the center of the original circle of the stationary volute. CONSTITUTION:In this scroll type compressor, the central ends of a volute 202 of a stationary scroll member and a volute 212 of a movable scroll member are formed in a bulb shape, and a discharge hole 204 is bored on the side wall near the spiraling original point of the volute 202 of the stationary scroll member, therefore, the reflation volume is reduced nearly to nil even though the discharge hole 204 is made large to some extent in order to keep the pressure loss of a fluid low as it passes through the discharge hole 204. In addition, the fluid compression power caused by reflation of the compressed fluid in a fluid pocket 302 formed at the periphery in the radial direction of one volute scarecely increases, thereby the power efficiency of the compressor can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a positive displacement fluid compression device, in particular, a device that applies a pair of spiral motions (revolutionary motion only) to reduce and contract the volume while moving the sealed space formed between both spiral bodies toward the center. The present invention relates to a scroll compressor that discharges compressed fluid from the center.

The compression principle of such a scroll compressor itself has been known for a long time, such as in US Pat. No. 801,182.

Here, the principle of compression operation of a scroll type compressor will be explained with reference to FIG.

They are arranged intermeshing with each other to form a limited fluid pocket, one spiral 1 connected to the other spiral 2.
The spiral winding body 1 rotates on its axis so that the base circle center (0) of one spiral winding body 1 revolves around the base circle center (0) of the other spiral winding body 2 with a radius O-0'. When the fluid pocket 6 is moved while inhibiting the movement, the fluid pocket 6 gradually decreases its volume and moves toward the center. That is, from the state of FIG. 1(a), the revolution angle of the spiral wound body 1 is changed to FIG. 1(b) showing 90 degrees, FIG. 1(C) showing 180 degrees, and FIG. 1(d) showing 270 degrees. As shown, when one of the spiral bodies 1 is moved, the volume of the fluid pocket 3 formed at the radial outer periphery of the spiral body gradually decreases as it moves toward the center. 360°
In the rotated figure 1 (a), both pockets move to the center and connect with each other, and in the rotated figure 1 (b), the pockets are moved further by 90 degrees.
c>, as shown in (d), the fluid pocket filter is caught,
It becomes almost zero in Fig. 1(d). During this time, Figure 1 (b)
The outer fluid pocket that has begun to open is shown in Figure 1 (C) and (d).
In the process of moving from (a) to (a), new fluid is taken in to create a fluid pocket.

Therefore, if sealed disk-shaped side plates are provided at both axial ends of the spiral bodies 1 and 2, and a discharge hole as shown in 4 in Fig. 1 is provided in the center of one side plate, the radial outer circumference can be゛It was taken in. The fluid is compressed and discharged from the discharge hole 4.

Here, the compression operation of a conventional scroll compressor having a discharge hole formed in the center of the side plate based on the above operating principle will be explained with reference to FIG. 2, FIG. 3, as well as FIG. 1.

A discharge hole 4 is bored in the center of one side plate 6, and this side plate 6
A discharge valve mechanism 7 is provided on the surface opposite to the surface on which the spiral wound body 2 is provided.
8.9 is provided. As the volume of the fluid pocket 5 shown in FIG. 1(a) gradually decreases due to the revolution of the spiral body 1, the pressure of the fluid hermetically compressed in the fluid pocket 5 gradually increases, and the fluid is discharged. When the pressure becomes higher than the pressure of the fluid in the discharge chamber 10 separated from the fluid pocket 5 by the valve 7, the discharge valve 7 opens and the compressed fluid in the fluid pocket 5 flows out into the discharge chamber 10 through the discharge hole 4. From now on, spiral body 1
The fluid pocket 5 communicates with the fluid pocket 6 when the end surface of the outer wall of the spiral body 1 passes the end of the discharge hole 4 of the side plate 6, and the high-pressure compressed fluid remaining in the fluid pocket 5 is released into the fluid pocket. 6 and expands again in the fluid pocket 5 whose volume has increased, the pressure of the fluid in the fluid pocket 5 becomes lower than the pressure of the fluid in the discharge chamber 10, and the discharge valve 8 closes.

The volume of the fluid pocket 5 at the time when the end surface of the outer wall of the spiral body 1 passes through the end of the discharge hole 4 of the side plate 6 is referred to as the re-expansion volume.

With this re-expansion volume, when the fluid pocket 5 and the fluid pocket 6 communicate with each other, the pressure of the fluid in the fluid pocket 5 is reduced because the high-pressure compressed fluid remaining in the fluid pocket 5 re-expands. Fluid pocket 3 on the verge of communication with
The pressure rises rapidly from the fluid pressure of It gets bigger by that amount.

When the spiral of the spiral body is an involete curve, the outer wall surface of the spiral body is processed to be involete up to the base circle, and the inner wall is made involete at the outside of the point where the spiral bodies 1 and 2 begin to interfere with each other, On the inner side, the re-expansion volume can be minimized by connecting the ends of the outer wall with an appropriate curve so that the spiral bodies 1 and 2 do not interfere with each other. At this time, the position and size of the discharge hole 4 can be maximized by inscribing the inner wall of the spiral wound body 2 and the outer wall of the thinly wound body 1.

However, in an actual scroll compressor, the fluid flows through the discharge hole 4.
In order to reduce the pressure loss when passing through the discharge hole 4, the area of the discharge hole must be made larger by a certain degree than the maximum area, and the re-expansion volume is determined by the size of the discharge hole 4.

An object of the present invention is to obtain a scroll type compressor in which the re-expansion volume becomes almost zero even if the size of the discharge hole is increased to a certain extent, the power required to compress the re-expanded fluid is small, and the power efficiency is high. shall be.

Hereinafter, the present invention will be explained in detail with reference to FIGS.

The compressor consists of a front end plate 12 and a cup-shaped part 16 installed thereon.Using 1
1.

The front end plate 12 has a through hole 111 centered on the central axis of the housing 11, and a main shaft 15 is rotatably supported therein via a ball bearing ring 14. Therefore, the axis of the main shaft 15 coincides with the central axis of the casing 11. In addition, a shaft seal 17 is placed inside the front end play.
. Further, an electromagnetic clutch device 1 is provided on the outer periphery of the sleeve portion 16.
8, the rotational motion from an external drive source is transmitted to the pulley 171 of the electromagnetic clutch device 18 via a V-belt (not shown), and the rotational motion to the main shaft 15 is controlled by controlling the energization of the excitation coil 172. Controls the transmission of rotational motion. The front end plate 12 is fixed by bolts or the like so as to close the front end opening of the cup-shaped portion 13, and the joint surface thereof is sealed by an 0-1) ring 19.

The sleeve portion 16 is also fixed onto the end surface of the front end plate 12 by bolts or the like, and the joint surface is sealed by an O-ring 20.

A fixed scroll member 21 is disposed within the cup-shaped portion 13 closed by the front end plate 12.
-1 A movable scroll member 22, a movable scroll member drive mechanism, and a rotation prevention mechanism 26 are provided.

Here, the fixed scroll member 21 generally has a side plate 201
A spiral body 202 and θ are fixed on one side thereof so that the center thereof is eccentric from the center of the side plate by a distance RO/2.
The leg part 203 is provided on the side plate 201 on the opposite side from the spiral body 202, and the bottom part 121 of the knob-like part 1 is applied with the force from the outside of the cup-shaped part 13. It is fixed on the inner wall of the bottom part 121 by a bolt 24 which passes through and is screwed into the bottom part 121. In addition, the side plate 201 of the fixed scroll member 21 fixed within the cup-shaped portion 13 seals between its outer peripheral surface and the inner wall surface of the cup-shaped portion 16 with an O-ring 25, thereby reducing the space inside the cup-shaped portion 1. Suction chamber 26
and a discharge chamber 61.

The movable scroll member 22 is composed of a side plate 211 and a spiral winding body 212 fixed on one side of the side plate so that its center is offset by a distance RO/2 from the center of the side plate.
12 is engaged with the spiral body 202 of the fixed scroll member 21 with an angular deviation of 180°.

Furthermore, the movable scroll member 22 is connected to a drive mechanism and a rotation prevention mechanism, which will be described later, and revolves around a circular orbit having a radius R'o by the rotation of the main shaft 15, thereby performing a fluid compression operation which will be described later.

Here, the drive mechanism of the movable scroll member will be explained with reference to FIG. 5 as well as FIG. 4.

A large diameter portion 141 is formed at the inner end of the main shaft 15 that passes through the through hole 111 of the front end plate 12 .
11 and is supported by a ball bearing 14. Further, a drive pin 142 is provided on the tip end surface of the large diameter portion 141 at a position eccentric from the center so as to protrude in the axial direction.

On the other hand, on the side plate 212 on the opposite side to the surface on which the spiral body 212 of the movable scroll member 22 is fixed, an annular boss 2 is provided.
13 is formed. Here, the center of the annular post 213 is aligned with the center of the side plate 211. In addition, the boss 21
Inside 3 is a thick disk-shaped or short shaft-shaped push-sea.
2 are fitted and rotatably supported via a 2-dollar bearing 63. The bush 32 integrally has a disc-shaped balance weight 271 extending in the radial direction, and has an axial hole 272 on the surface facing the large diameter portion 141 of the main shaft 15. The aforementioned drive pin 142 is fitted into the hole 272 via the needle bearing 64. Therefore, the movable scroll member 22 is rotatably supported on the drive pin 142. In addition,
The scroll member 22 is prevented from moving in the rotational direction by a rotation prevention mechanism shown at 26 in FIG.

Here, this rotation prevention mechanism will be explained with reference to FIG. 6 as well as FIG. 4.

The rotation prevention mechanism 23 is connected to the boss 2 of the movable scroll member 2'2.
13, and the outer peripheral surface is joined to the inner wall surface of the cup-shaped portion 16, and the front end plate, -)
It has a fixing ring 221 fixed on the end face of 12.

Side plate 21 of movable scroll member 22 of fixed ring 221
A pair of key grooves 221a and 221b extending on one diameter are provided on the axial end face facing the main body 1. Further, a movable ring 222 is arranged between the fixed ring 221 and the side plate 211 of the movable scroll member 22, and the movable ring 222 has a pair of rings extending in one diameter direction on a surface facing the fixed ring 221. It has keys 222a and 222b, and these keys 222a and 222b are fitted into key grooves 221a and 22Nb of the fixing ring 221, respectively. As a result, the movable ring 222 is connected to the fixed ring 222.
1, but is slidable in one direction perpendicular to the axis, ie in the direction of extension of the keyway and key. The movable ring 222 is still attached to the movable scroll member 22
A key 222a is provided on the axial end face opposite to the side plate 211 of the key 222a.
Keys 222c and 222d extend on one diameter 90° from the extending direction of key 222b. On the other hand, a movable ring 222 is attached to the side plate 211 of the movable scroll member 220.
Keys 222C, 2 are placed on both sides of the post 213 on the surface facing the
It has a pair of keyways for receiving 22d.

As a result, the movable scroll member 22 moves to the movable ring 222.
Although the key is prevented from rotating relative to the key, it is allowed to slide in the direction in which the key and the keyway extend.

Next, in addition to FIG. 4, the shape of the central end of the spiral body 202 of the fixed scroll member 21 and the spiral body 212 of the movable scroll member 22, the discharge hole 204, and the discharge valve mechanism are shown in FIG.
This will be explained with reference to a).

The shape of the central end of the spiral body 202 of the fixed scroll member 21 and the spiral body 212 of the movable scroll member 22 is such that when the movable scroll member 22 revolves on a circular orbit due to the rotation of the main shaft 15, there is a gap between the spiral bodies 202 and 212 of the movable scroll member 21. A line contact portion is formed on the spiral wound body, and the wire contact portion is formed into a bulbous shape having an appropriate curve so that both spiral bodies may interfere with each other and the line contact portion is exposed on the surface of the spiral body and moves toward the center.

At this time, if the shape of the bulbous central end of the spiral body 202 of the fixed scroll member 21 and the spiral body 212 of the movable scroll member 22 is not the same, the shape of the fluid pocket 302 shown in FIG. 7(a) is And fluid pocket filter 01
The two shapes are not symmetrical, and the overall force and balance of the compressor becomes strange, resulting in large fluctuations in torque.

In order to reduce the variation in torsion, the bulbous shapes of the central ends of both spiral bodies are made the same.

In addition, an elliptical discharge valve chamber 205 for providing a discharge valve mechanism is provided at the bulb-shaped central end of the spiral body 202 of the fixed scroll member 21 on the surface of the side plate 201 to which the spiral body 202 is fixed. A concave hole is formed from the opposite side, and the discharge valve chamber 205
Inside, there is a discharge valve 27 that functions as a check valve as shown in FIG. 8, and a discharge valve holder 28 that limits the opening degree of the discharge valve 27.
is provided.

Further, the discharge valve chamber 205 communicates with a fluid pocket 602 shown in FIG. 7(a) through a discharge hole 204 formed in the side wall surface of the spiral body 202 near the center of the basic circle of the spiral.

The above-mentioned discharge valve 27 is a reed valve, and is inserted so as to be pressed against the inner wall surface of the discharge valve chamber 205 by its spring force, and the discharge valve holder 28 is press-fitted inside the discharge valve 27.
The discharge valve 27 and the discharge valve holder 28 are attached to the side plate 20 of the fixed scroll member 21 so that they do not come out from the discharge valve chamber 205.
It is held down by a holding plate 29 fixed to 1 with screws 30.

Note that the discharge valve mechanism described above is just one example, and is not limited to the discharge valve mechanism, and any discharge valve mechanism that functions as this steady stop valve may be used.

1 Furthermore, the shape of the discharge valve chamber 205 is not limited to an elliptical shape, and may be any shape.

Furthermore, in the above description, the discharge valve chamber 205 is formed in a concave shape from the side opposite to the surface on which the spiral body 202 is fixed to the side plate 201 of the fixed scroll member 21.
As shown in Figure 0, the discharge valve chamber 205 is concave from the spiral body side.
and a communication hole 206 in the side plate to connect the discharge valve chamber 205.
The discharge chamber filter 1 may be communicated with the discharge chamber filter 1. in this case,
The discharge valve 27 and the discharge valve holder 28 are fixed by a snap ring 35.

Next, we will discuss the fluid compression operation of this scroll compressor in the fifth section.
The explanation will be made with reference to FIG. 7 in addition to the drawings.

As described above, the movable scroll member 22 is connected to the drive mechanism and the rotation prevention mechanism, and revolves around a circular orbit having a radius RO by the rotation of the main shaft 15 to perform a fluid compression operation.

Here, the radius Ro of the circular orbit is generally spaced apart from (pitch of the spiral body) -2 x (wall thickness of the spiral body), and the movable scroll member 22 moves on a circular orbit of radius Ro by 150 rotations of the main shaft. It will orbit above. This creates a line contact between both spirals, which moves toward the center along the surface of the spiral, resulting in a fluid pocket moving toward the center of the thin body while decreasing its volume. Tree.

That is, from the state of FIG. 7(a), FIG. 7(b) shows that the revolution angle of the spiral body 212 is 90°, and FIG. 7(b) shows that the revolution angle of the spiral body 212 is 180°.
C), a fluid pocket 60 formed on the radial outer periphery of one spiral body as shown in FIG. 7(d) showing 270°.
The volume of 1 gradually decreases as it moves toward the center. In FIG. 7(d) rotated by 270 degrees, both fluid pocket filters 01 move to the center and connect to each other to form a fluid pocket 602.
Figure 7 (a) (b) (C
), the fluid pocket 302 is pinched, and when the pressure of the fluid in the fluid pocket 302 becomes higher than the pressure of the fluid in the discharge valve chamber 205, the discharge valve 27 opens and the fluid in the fluid pocket 302 is released from the discharge valve chamber 205. flows into.

Therefore, the suction chamber 26 inside the casing 11 is passed from the external fluid circuit through the suction port provided on the outer periphery of the casing 11.
The fluid that has flowed into the spiral body is taken into the fluid pocket from the outer end of both spiral bodies, and the compressed fluid flows from the fluid pocket in the center of both spiral bodies to the discharge hole 204 and the discharge valve chamber 205.
through the discharge chamber 61, from where it flows out to the external fluid circuit via a discharge port provided on the casing 11.

In the process of the above fluid compression operation, the revolution angle of the spiral body 212 further moves by 90' from the state shown in FIG. 7(b).
Between the figure (c), the spiral body 2 of the fixed scroll member 21
02 and the two line contact portions of the spiral body 212 of the movable scroll member 22 pass the end of the discharge hole 204, the fluid pocket filter O2 has two fluid pockets 301 and the discharge hole 20.
The compressed fluid remaining in the fluid pocket filter 02 communicates with the fluid pocket filter 02, which was sealed with a fluid with a lower pressure than that of the frame, and is re-circulated in the fluid pocket 7 302, which has a larger volume. Upon expansion, the pressure of the fluid in the fluid pocket 302 is lower than the pressure of the fluid in the discharge chamber 205, and the discharge valve closes.

However, the above-mentioned re-expansion volume of the present scroll compressor is determined by making the central end shapes of the spiral body 202 of the fixed scroll member 21 and the spiral body 212 of the movable scroll member 22 bulbous. By forming a discharge hole 204 in the side wall surface near the spiral origin of the winding body 202, the pressure loss when the fluid passes through the discharge hole 204 can be reduced even if the discharge hole 204 is enlarged to some extent (especially If the wall is made larger in the height direction, the re-expansion volume will not be affected at all by making the discharge hole thicker, and the fluid will be compressed by the re-expansion of the compressed fluid in the fluid pocket 602. There is almost no increase in power, and the power efficiency of the compressor can be increased.

As explained above, the present invention has a fixed and movable cylindrical spiral body whose center end shape is bulb-shaped, and a discharge valve chamber in which a discharge valve mechanism is provided is bored in the bulb-shaped center end of the fixed spiral body. In addition, by providing a discharge hole that communicates the discharge valve chamber with the fluid pocket on the side wall surface of the fixed spiral body near the center of the base circle, the re-expansion volume can be reduced to almost zero, and the re-expansion volume can be reduced to almost zero. It is possible to reduce the fluid compression power caused by this, and obtain a scroll compressor with high power efficiency.

Furthermore, by making the fixed and movable tube bodies and the bulbous center and end shapes of the winding bodies the same, the fluid pockets formed by both spiral winding bodies are made symmetrical, and the force balance of the compressor is improved. This makes it easy to reduce torque fluctuations.

The above describes an example in which the present invention is applied to a scroll type compressor equipped with a specific drive mechanism and a rotation prevention mechanism, but these do not limit the present invention, and the present invention applies to scroll type compressors with various other configurations. Applicable to compressors.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(d) are diagrams for explaining the compression principle of the scroll compressor according to the present invention, and FIGS. 1(a) to 1(d) are diagrams showing states at different angular positions. 6 is a partial perspective view showing the position of the discharge hole of a conventional scroll compressor, FIG. 6 is a partial view illustrating the relationship between the discharge hole and the discharge valve mechanism of a conventional scroll compressor, and FIG. 4 is a partial perspective view of the conventional scroll compressor. A vertical sectional view of a scroll compressor showing an example of the invention, FIG. 5 is an exploded perspective view explaining the drive mechanism, FIG. 6 is an exploded perspective view explaining the rotation prevention mechanism, and FIGS. 7(a) to ( d) is a diagram for explaining the compression operation of the scroll compressor of the present invention, and (a) to (
d) is a diagram showing the state of different angular positions, FIG.
An exploded perspective view for explaining the volume valve mechanism, and FIG. 9 is a vertical cross-section of a scroll compressor showing an example in which the discharge valve chamber is bored in a concave shape from the side opposite to the surface on which the spiral body is fixed on the side plate. Figure, 1st
FIG. 0 is an exploded perspective view for explaining the discharge valve mechanism. 11...Compressor housing 15...Main shaft 142...
・Drive pin/ 21...Fixed scroll member 22・Movable scroll member 23...Rotation prevention mechanism 32...Pushy - 1st F
I! J Figure 1 3 Figure 2 Figure 7 (a) Figure 7 (b) Figure 7 (C) Figure 7 (d)

Claims (1)

[Claims] A compressor housing has a fluid inlet and a fluid outlet, and a first spiral body having a base circle center eccentric from the center of the plate is disposed on one surface of a first plate. A fixed scroll member fixed to a fixed scroll member, and a base circle center on one surface of a second plate body eccentrically from the center of the plate body, and a distance from the center of the first spiral body to the center of the orbit radius Ro. the second spiral body is superimposed on the fixed scroll member such that the second spiral body meshes with the first spiral body at an angular shift and forms a closed fluid pocket therebetween; A movable scroll member, a main shaft rotatably supported by the housing, a drive mechanism eccentrically provided at the inner end of the main shaft and coupled to the movable scroll member, and A Suffeal type compressor in which the fluid pocket moves toward the center of the cylindrical spiral body while decreasing its volume due to the circular orbit movement of the movable scroll member generated by the movable scroll member movement mechanism, thereby compressing the fluid. In the above, when the movable scroll member moves in a circular orbit around the central end shape of the two spiral bodies, the fixed scroll member and the movable scroll member, a line contact portion is formed between the two spiral bodies, and both spiral bodies The line contact part should be shaped like a bulb with an appropriate curve so that it can move toward the center of the spiral body without interfering with the surface of the spiral body. 1. A scroll type compressor, characterized in that a discharge valve chamber is formed, a discharge valve mechanism is provided in the discharge valve chamber, and a discharge hole communicating with the base of a spiral body is bored.