JPH0353031Y2 - - Google Patents

Description

[Detailed description of the invention] The invention is based on the invention that the driven member has a central axis with a radius of R.
Improvements in the rotation prevention mechanism of a device, such as a scroll-type fluid device, which has a driven member that is driven in a circular orbit, and which needs to be prevented from rotating during the circular orbital motion. Regarding.

A scroll type compression device will be described as the most common example of this type of device.

This device prepares two scroll members with spiral bodies fixed on a single plate, and overlaps them by interlocking them with the angles of both spiral bodies shifted.
With one scroll member fixed and the other movable, the circular orbital motion of the movable scroll member causes a volume reduction as the closed fluid pocket formed between both scroll members moves toward the center. It compresses fluid by tightening it.
When the movable scroll member moves in a circular orbit, it is necessary to prevent the movable scroll member from rotating itself.

An example of such a rotation prevention mechanism is U.S. Pat.
An example of its application will be described with reference to FIG. 1, which shows a recently proposed scroll compressor in cross section.

In the figure, this compressor has a compressor housing 10 consisting of a front end plate 11 and a cup-shaped casing 12 installed therein.

The front end plate 11 is connected to the housing 1
The main shaft 14 is rotatably supported in the through hole 111 through a ball bearing 13 through a through hole 111 whose center is on the central axis of the main shaft. Further, the front end plate 11 has a sleeve portion 15 projecting forward so as to surround the outer periphery of the main shaft 14, and a shaft seal 16 is disposed within the sleeve portion 15. Further, an electromagnetic clutch device 17 is disposed on the outer periphery of the sleeve portion 15, and rotational motion from an external drive source is transmitted to a pulley 171 of the electromagnetic clutch device 17 via a V-belt (not shown) to excite it. Transmission of the weekly motion to the main shaft 14 is controlled by controlling the energization of the coil 172. The front end plate 11 is fixed by bolts or the like so as to close the front end opening of the cup-shaped casing 12, and the joint surface thereof is sealed by an O-ring 18. The sleeve portion 15 is also fixed onto the end surface of the front end plate 11 with bolts or the like, and the joint surface is sealed with an O-ring 19.

A fixed scroll member 20, a movable scroll member 21, a movable scroll member drive mechanism, and a rotation prevention mechanism 22 are contained in the cup-shaped casing 12 whose opening is closed by the front end plate 11.
is installed.

Here, the fixed scroll member 20 generally includes a side plate 201 and a spiral body 202 fixed on one surface of the side plate so that its center is eccentric from the center of the side plate by a distance Ror/2 (where Ror is the radius of the circular orbit of the movable scroll member). It is composed of a leg portion 203 provided on the side plate 201 on the opposite side to the spiral body 202,
The leg portion 203 is fixed onto the inner wall of the bottom portion 121 by a bolt 31 which penetrates the bottom portion 121 of the cup-shaped casing 12 from the outside of the cup-shaped casing 12 and is screwed into the leg portion 203 . Also, the cup-shaped casing 1
The side plate 201 of the fixed scroll member 20 fixed in the cup-shaped casing 12 forms a space inside the cup-shaped casing 12 with a suction chamber 25 by sealing between its outer peripheral surface and the inner wall surface of the cup-shaped part 20 with an O-ring 32. It is partitioned into a discharge chamber 26. Furthermore, the side plate 201
A communication hole 204 is bored in the center of the scroll member to communicate the discharge chamber 26 with the sealed space formed between the scroll members.

The movable scroll member 21 is composed of a side plate 211 and a spiral body 212 fixed on one side of the side plate so that its center is offset by a distance Ror/2 from the center of the side plate. It is engaged with the body 202 with an angular deviation of 180°. Furthermore, the movable scroll member 21 is connected to a drive mechanism and a rotation prevention mechanism, which will be described later.
It revolves around the circular orbit of Ror and performs the fluid compression operation described above.

Here, the radius Ror of the circular orbit is generally given by (pitch of the spiral body) - 2 x (wall thickness of the spiral body)/2. Furthermore, the movable scroll member 21 is arranged such that the center of the spiral body 212 of the movable scroll member 21 is separated from the center of the spiral of the spiral body 202 of the fixed scroll member 20 by a distance Ror,
The movable scroll member 21 is rotated by the rotation of the main shaft 14.
will revolve on a circular orbit with radius Ror. As a result, a line contact part is formed between both spiral bodies, and this line contact part moves toward the center along the spiral body surface, and as a result, the fluid pocket moves toward the center of the spiral body while decreasing its volume. do.

Therefore, the housing 10 is supplied from the external fluid circuit through the suction port provided on the outer periphery of the housing 10.
The fluid that has flowed into the suction chamber 25 inside is taken into the fluid pocket from the outer end of both spiral bodies, and the compressed fluid passes from the fluid pocket at the center of both spiral bodies to the discharge chamber 26 through the communication hole 204. From there, it flows out into the peripheral fluid circuit via a discharge port provided on the housing 10.

Next, the drive mechanism of the movable scroll member will be explained with reference to FIG. 2 as well as FIG. 1.

A large diameter portion 141 is formed at the inner end of the main shaft 14 that passes through the through hole 111 of the front end plate 11, and the ball bearing 13 has the large diameter portion 141 disposed in the through hole 111 of the front end plate 11. It is supported by Also, large diameter part 1
A drive pin 142 is provided on the tip end surface of the shaft 41 at a position eccentric from the center so as to protrude in the axial direction.

On the other hand, the spiral body 2 of the movable scroll member 21
An annular boss 213 is formed on the side plate 212 on the opposite side to the surface on which the ring 12 is fixed. Here, the center of the annular boss 213 is aligned with the center of the side plate 211. A push 27 in the form of a thick disk or short shaft is fitted into the boss 213 and rotatably supported via a needle bearing 28 . The bush 27 is integrated with a disc-shaped balance weight 27 extending in the radial direction.
1, and the large diameter portion 14 of the main shaft 14.
The drive pin 142 has an axial hole 272 on the surface facing the drive pin 1 , and the drive pin 142 described above is fitted into the hole 272 via a needle bearing 29 . Therefore, the movable scroll member 21 is rotatably supported on the drive pin 142. In addition, 3
0.143 is a balance weight for canceling the mechanical imbalance caused by the circular orbit movement of the balance weight 271 and the movable scroll member 21. Further, the scroll member 21 is prevented from moving in the rotational direction by a rotation prevention mechanism shown at 22 in FIG.

Here, this rotation prevention mechanism will be explained with reference to FIG. 3, which is an exploded view, in addition to FIG. 1.

The rotation prevention mechanism 22 includes a movable scroll member 21
A ring-shaped fixing race 22 is disposed on the outer circumference of the boss 213 near the front end plate 11 and has its outer circumferential surface joined to the inner wall surface of the cup-shaped portion 12 to abut against the end surface of the front end plate 11.
1, and a fixing ring 222 abutting the end face of the fixing race 221 so as to cover it, and these are fixed to the end face of the front end plate 11 by pins 223. On the other hand, the boss 21 near the side plate 211 of the movable scroll member 21
3 has a ring-shaped movable race 214 on the end face opposite to the spiral body 212 of the side plate 211, and covers the movable race 214 with a slight gap between it and the end face of the fixed ring 222. As shown in FIG.

As shown in FIG.
5 and the fixed ring 222, a plurality of pockets 215a and 222a are perforated in the axial direction at positions where they overlap each other when both rings are centered and overlapped, and a ball element 224 is held between the opposing pockets. ing.

Now, the rotation prevention effect will be explained with reference to FIG. 4, which shows the relationship between the movable ring and the fixed ring as seen from the movable scroll member side.

The rotation is prevented by the pocket 22 of the fixing ring 222.
The edge of 2a and the pocket 215 of the movable ring 215
This is done by sandwiching the ball element 224 with the edges of a. That is, when the movable scroll member is driven counterclockwise in the figure, the movable ring 215 also moves in a circular orbit so that its center axis draws a circle with radius Ror, but the movable scroll member also moves in the same direction due to the reaction force of the compressive force. Because rotational force is generated, the movable ring 2
It attempts to rotate counterclockwise around the central axis of No. 15. However, the nine ball elements 2 on the right side of the figure
24 is sandwiched between the edge of the pocket 222a of the fixed ring 222 and the edge of the pocket 215a of the movable ring 215, the movable ring 215 cannot rotate, thereby preventing the movable scroll member from rotating. Ru. In the illustrated state, the center of the movable ring 215 is at the uppermost position in the figure, and the rotation blocking force distribution is as f _C1 to f _C4 , with the ball element closest to the right in the figure making the largest contribution. The nine ball elements 224 on the left half of the figure, which become smaller as they move away from each other, do not serve to prevent rotation. However, the pressure applied in the axial direction of the movable scroll member due to the reaction force of the compressive force is thrust supported by the fixed race 221 via the movable race 214 and all the ball elements 224. Therefore, the inner diameter and outer diameter of the movable race 214 and the fixed race 221 may be large enough to secure the transfer area of the ball element 224.

Therefore, as shown in FIG.
4 and the diameter of the fixed race 221 to the ball element 224.
It is also possible to reduce the diameter to a diameter sufficient to secure the transfer area, and fix only the movable ring 215 and fixed ring 222 with pins 216 and 223, respectively.

Here, pin 21 is attached to both rings 215 and 222.
The pin holes 215b and 222b, which were drilled for inserting the pins 6 and 223, were straight holes, as is clear from FIG. Therefore, as the ball element 224 moves, both rings 215 and 22
2 moves slightly, the pins 216 and 223 cause a grinding motion, and the pins 216 and 223 move into the pin hole 2.
There was a risk that the pins 216, 223 would come off due to the force exerted in the direction of the pins 15b, 222b. In order to eliminate this phenomenon, the diameter of the pin hole provided in the front end plate or movable scroll member into which the pin is inserted is adjusted to
Pin holes 215b, 222b provided in 15, 222
It is possible to consider a configuration in which the diameter of the pins is smaller than the diameter of the pins and the pins 216 and 223 are tightly press-fitted, or a configuration in which the pins are not split spring pins with straight openings, but instead use spring pins with large corrugated openings. Even with this configuration, it was not sufficient to prevent the pin from moving in the direction of coming out of the pin hole.

In addition, in order to prevent such slight movement of the ring, it is possible to fix the ring by caulking, but caulking is difficult, especially when fixing the ring to the front end plate side, so it is not recommended. Not only is it impossible to fix the ring, but when fixing it, it is necessary to fix the ring with some kind of positioning structure and then process it, and the simplest and most accurate positioning structure is to use a pin.

Therefore, the present invention is an attempt to improve such a rotation prevention mechanism, and an object of the present invention is to easily and reliably fix the ring constituting the rotation prevention mechanism.

That is, the present invention provides a movable scroll member to be driven to draw a circular orbit with a preset radius, and a drive mechanism coupled to the movable scroll member to give the movable scroll member the circular orbital motion. and a front end plate that supports and fixes the drive mechanism, and a mechanism that prevents rotation of the movable scroll member during circular orbital motion of the movable scroll member, the rotation prevention mechanism. is a fixed ring fixed to the front end plate by a C-shaped pin, and a movable scroll member fixed to the movable scroll member by a C-shaped pin so that there is a slight gap between the fixed ring and the fixed ring. Rotation is prevented by a ball element sandwiched between a plurality of circular pockets drilled on both rings, and a folded part is provided at the insertion end of the C-shaped pin that fixes each ring. is formed, and a part of the C-shaped pin outer peripheral portion is in surface contact with the inner wall surface of the C-shaped pin insertion hole bored in the movable scroll member and the front end plate, respectively.

The present invention will be described below with reference to drawings showing embodiments.

The movable ring 215 and the fixed ring 222 are connected to the movable scroll member 21 by the C-shaped pin 23 without using the movable race 214 and the fixed race 221, respectively.
The side plate 211 of the front end plate 11 is positioned and directly fixed to the inner wall surface of the front end plate 11.
Here, the C-shaped pin 23 is connected to the through hole 215 of each ring.
a, has an outer diameter slightly larger than the hole diameter of 222a,
In addition, as shown in FIG. 8, a folded portion 231 is provided at the insertion side end.

When fixing, insert the C-shaped pin 23 into the through hole 215.
a, 222 and the side plate 21 of the movable scroll member 21
1 and the insertion hole 11a of the front end plate 11. At this time, the tip of the folded part 231 is inserted into the insertion hole 11a, 211.
By biting into the inner wall part of a, the prevention of falling off becomes stronger. Further, since a part of the outer circumference of the C-shaped pin 23 is brought into surface contact with the inner wall surfaces of the insertion holes 11a and 211a, loosening of the C-shaped pin 23 due to the scraping movement can be prevented.

Therefore, after the C-shaped pin 23 is fitted into the pin holes 11a and 211a formed in the front end plate 11 or the side plate 211 of the movable scroll member 21, the folded portion 231 is inserted into the pin hole 11.
a, 211a engages with the inner wall surface to prevent the C-shaped pin 23 from moving in the axial direction, thereby preventing the pin itself from coming off. Furthermore, since the C-shaped pin is press-fitted into the through hole, each ring can be prevented from coming off.

Note that if a press-fit pin 24 as shown in FIG. 9 is press-fitted into the hollow portion of the C-shaped pin 23, the engagement state of the C-shaped pin 23 in the pin hole will be strengthened, and the fixing can be performed more reliably.

As described above, in the present invention, the fixed ring and the movable ring constituting the rotation prevention mechanism are fixed by a pin having a folded part at the end on the insertion side, and the folded part of the pin is inside the pin hole. Since it engages with the wall surface, even if a force is applied to the pin in the direction of pulling it out of the pin hole due to the movement of the ring while the device is driving, the pin can be prevented from moving, and the pin itself can be prevented from coming out. In addition, the ring can be securely fixed.

Further, since movement of the pin is reliably suppressed, this pin can be used both for fixing and positioning the ring, making it easier to assemble the device.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a scroll compressor to which the present invention is applied, FIG. 2 is an exploded perspective view of a drive mechanism thereof, and FIG. 3 is an exploded perspective view of a rotation prevention mechanism that also serves as a thrust bearing. Fig. 4 is a diagram showing the relationship between the movable ring, the fixed ring, and the ball element in a sectional view taken along the - line in Fig. 1 in order to explain the principle of rotation prevention, and Fig. 5 is the fixing structure of the movable ring and the fixed ring. FIG. 6 is a cross-sectional view showing another conventional example of the ring, FIG. 6 is a cross-sectional view for explaining the shape of the pin hole provided in the ring used in FIG. A sectional view for explaining the structure in which the fixed ring and the movable ring are fixed, FIG. 8 is a sectional view of the pin used in FIG. 7, and FIG. 9 is a sectional view of another embodiment of the present invention shown in FIG. FIG. 3 is a side view of a press-fit pin used with the pin. 10...Compressor housing, 11...Front end plate, 12...Cut-shaped portion, 20...
... Fixed scroll, 21 ... Movable scroll, 2
2... Rotation prevention mechanism, 214... Movable race, 2
15...Movable ring, 23...Pin, 24...Press-fit pin.

Claims (1)

[Scope of utility model registration request] a movable scroll member to be driven to draw a circular orbit with a preset radius; a drive mechanism coupled to the movable scroll member for imparting the circular orbital motion to the movable scroll member; In a scroll-type fluid device including a front end plate that is supported and fixed, and a mechanism that prevents rotation of the movable scroll member during circular orbital movement of the movable scroll member, the rotation prevention mechanism includes a front end plate that is supported and fixed to the front end plate. a fixed ring fixed to the movable scroll member by a C-shaped pin, and a movable ring fixed to the movable scroll member by a C-shaped pin such that there is a slight gap between the fixed ring and the fixed ring; Rotation is prevented by a ball element held between a plurality of circular pockets bored on the ring, and a folded portion is formed at the insertion end of the C-shaped pin that fixes each ring, and A rotation prevention mechanism for a scroll-type fluid device, characterized in that a part of the outer periphery of the C-shaped pin is in surface contact with the inner wall surface of the C-shaped pin insertion hole bored in the movable scroll member and the front end plate, respectively. .