JP3075328B2 - Compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor, and is effective, for example, as a refrigerant compressor for an air conditioner for an automobile.

[0002]

2. Description of the Related Art Such scroll type compressors are disclosed in many patents and literatures, and the operation principle is well known. In a scroll type compressor, a closed space is created between a plurality of contact lines formed by a fixed scroll member and a movable scroll member meshing with each other. Then, when the orbiting scroll makes a revolving motion, the contact line moves toward the center along the wall of the spiral body, and the enclosed space also moves along the center while reducing the volume, thereby performing compression. .

However, since a plurality of contact lines are formed at the same time, it is necessary to reduce the error of the shape of the spiral from a predetermined shape to the order of several microns, and the precision of the relative position of both scroll members is severe. Things are required. Therefore, means for varying the radius of the orbiting motion of the movable scroll along the shape of the scroll member have been proposed by many patent specifications.

For example, in Japanese Patent Publication No. 58-19875, a cylindrical driving pin is provided at an end of a shaft, a hole is formed in a bush that gives a revolving motion to a movable scroll, and the driving pin is rotatably inserted into the hole. Are fitted.
Further, it is proposed that the drive pin position is located at a distance larger than the radius of the revolving motion from the center of the shaft and is shifted in a rotational direction from a line connecting the center of the bush and the center of the shaft. I have.

Japanese Patent Application Laid-Open No. 62-162786 discloses a movable scroll and an intermediate member for transmitting rotation from a shaft to the movable scroll (the above-mentioned Japanese Patent Publication No. 58-1987).
No. 5 is slidably mounted in a plane perpendicular to the axis of the shaft.

[0006]

However, the device disclosed in Japanese Patent Publication No. 58-19875 merely fits a drive pin into a hole provided in a bush, and similarly disclosed in Japanese Patent Application Laid-Open No. 62-162786. In this case, since the guide provided on the shaft end face is merely fitted into the guide groove provided in the bush, the bush moves in the direction of the movable scroll. For this reason, since the bush starts to slide on the end plate of the movable scroll, an excessive driving force is required, and severe burning occurs. In the scroll compressor, a centrifugal force acts on the orbiting scroll in an eccentric direction during the revolving motion of the orbiting scroll. Since the centrifugal force acts as a rotational moment for tilting the bush, the bush tilts in a structure in which the bush is not locked, such as the scroll compressor having the above-described configuration. Further, during operation of the compressor, a compression reaction force due to compression acts on the orbiting scroll, and this compression reaction force also acts as a rotational moment for tilting the bush, and the bush tilts. As a result, while the needle bearing which supports the bush has a partial contact,
A problem arises in that a one-sided contact occurs between the end face of the bush and the opposite end face of the shaft.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a scroll compressor which operates with high accuracy for a long period of time by regulating the tilting of the bush and the movement in the axial direction of the shaft.

[0008]

In order to achieve the above object, the present invention has a fixed scroll member having a spiral formed on an end plate, and a spiral formed on an end plate. A movable scroll member which is incorporated so as to be displaced from the center of the scroll member, a shaft which rotates by receiving a driving force, and a center of the shaft at an end of the shaft by a radius of the revolving motion of the movable scroll member. A bush that is arranged eccentrically from and provides a revolving motion to the orbiting scroll member, and has a rotation preventing mechanism that allows only the orbiting of the orbiting scroll member and prevents the orbital rotation. The closed space between the movable scroll member and the fixed scroll member moves toward the center of the spiral body while reducing the volume, and The scroll compressor compression of the fluid takes place, wherein the end plate of the movable scroll member are engaging portion formed with said bush for receiving a revolution drive force while permitting rotation of said bushing, before A groove having a shape having a rotation transmitting surface is provided in the bush so as to penetrate the bush, and a drive key having a surface abutting on the rotation transmitting surface is provided at an end of the shaft. The groove of the bush has a predetermined gap with the drive key in the moving direction so that the bush can move along the rotation transmitting surface of the drive key, and has a small clearance in the width direction. Technical means is employed in which a locking means is provided at the tip of the driving key, the locking means for restricting movement of the bush in the axial direction .

[0009]

Since the compressor of the present invention has the above-described structure, even if the bush tries to tilt or move in the axial direction of the shaft due to the centrifugal force acting on the balance weight, the end face is driven. Since the key contacts the locking means disposed at the tip of the key, its tilting and movement in the shaft axial direction are restricted. For this reason, it is possible to prevent one end of the engagement portion with the bush provided on the end plate of the movable scroll member, and to prevent one end between the end surface of the bush and the end surface of the shaft facing the bush. In addition, since the movement of the bush in the shaft direction is restricted, the bush does not slide on the end plate of the movable scroll, so that unnecessary driving force is not consumed and seizure does not occur. A scroll compressor that operates with high accuracy can be provided. Further, as the tilting of the bush can be prevented, a gap in the longitudinal direction between the bush groove and the drive key can be provided with a margin, and the sliding stroke of the bush can be increased .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a compressor of a refrigeration cycle of a vehicle air conditioner will be described in detail with reference to the drawings. FIG. 1 shows an embodiment of the present invention. In this compressor, a housing is formed by a rear housing 500 and a front housing 400 fastened and disposed by bolts (not shown) so as to close an opening of the rear housing 500. The front housing 400 has a holding hole in the center, in which the bearing 700 is mounted,
The shaft 100 is rotatably supported. Further, the front housing 400 has a cylindrical boss 401 and a shaft seal 800 is incorporated therein.
A magnet clutch (not shown) is mounted on the outer periphery of the boss 401, and the rotational force of the vehicle driving engine is transmitted to the shaft 100 via the magnet clutch. A fixed scroll member 300 is fitted into the rear housing 500 and is fixed to the bottom of the rear housing 500 by a bolt (not shown). The rear housing 500 is separated into a high-pressure chamber 501 and a low-pressure chamber 502 by the fixed scroll member 300 and the O-ring 801, and communicates with the high-pressure chamber 501 and the low-pressure chamber 502. Has a mouth.

In the rear housing 500, the movable scroll member 200 is arranged so that the spiral bodies mesh with each other at an angle shifted from the fixed scroll member 300. The movable scroll member 200 is linked to a rotation preventing mechanism, and is restricted from rotating. Further, the movable scroll member 200 is connected to a bush 101 according to the present invention, which will be described later, performs a revolving motion, and compresses the refrigerant gas.

Since the radius R of the revolving motion is determined by the shapes of the two scroll members, the movable scroll 200 is arranged so that the centers of both the scrolls are separated by the radius R. That is, the rotation of the shaft 100 causes the movable scroll member 200 to move through the bush 101.
Performs a revolving motion of radius R. by this,
The contact line formed between the scrolls moves toward the center along the spiral shape, and the enclosed space moves toward the center while reducing the volume. Thus, the compression of the refrigerant is performed. Further, a discharge port 503 for discharging the compressed refrigerant gas to the high-pressure chamber 501 is formed in the center of the fixed scroll member 500. Also, a discharge valve 504 and a discharge valve 50 for preventing the discharged refrigerant gas from flowing back from the high-pressure chamber 501 to the closed space of the spiral.
A stopper 505 that regulates the lift amount of No. 4 is also attached.

Next, the driving mechanism of the movable scroll member 200 will be described with reference to the drawings. FIG. 2 shows the configuration of the drive mechanism. On the end face of the shaft 100. A drive key 100a is formed integrally with the drive key 100a. The drive key 100a
Is formed so as to be inclined by an angle θ in a direction opposite to the rotation direction with respect to a line passing through the center of the shaft as shown in FIGS. On the other hand, as shown in FIG. 5, the bush 101 is provided with a groove 101a that is fitted to the drive key 100a and receives a rotational driving force. The groove 101a
Are arranged such that the longitudinal dimension of the groove in this embodiment is longer than that of the drive key 100a. The width of the groove is set to be larger than the width of the driving key by several tens μ so that the bush 101 can smoothly slide in the longitudinal direction while being in contact with the driving key 100a. In order to further ensure smooth sliding movement, the surface roughness of the drive key 100a and the two-face wide surface of the groove 101a is suppressed to several μ by polishing. Further, a balance weight 102 is integrally attached to the bush 101 so as to cancel the centrifugal force due to the revolving motion of the movable scroll member 200. The balance weight 102 may be integrally attached to the shaft 100.

The shaft 100 and the driving key 1 described above
The positional relationship and action of the bush 101 and the bush 101 and the groove 101a will be described with reference to FIGS. FIG. 6 shows the relative positional relationship between the shaft 100 and the bush 101 in a state where all the components are assembled and the compressor is completed. The distance between the center 100b of the shaft and the center 101b of the bush is RI, which is substantially equal to the revolution radius R described above. The drive key 100a is installed so that its longitudinal direction is inclined by an angle θ in a direction opposite to the rotation direction of the shaft 100 with respect to a line passing through the center 100b of the shaft and the center 101b of the bush. When the shaft 100 rotates in the direction indicated by 100c in this state, the bush 101 receives a rotational driving force via the drive key 100a, and similarly starts rotating in the direction of 100c. here,
Since the movable scroll member 200 is engaged with the bush 101 via a bearing or the like, the rotation of the bush 101 causes the movable scroll member 200 to revolve and start compression. At this time, the movable scroll member 20
A compression reaction force due to compression acts on 0, and as a result, a compression reaction force as shown in FIG. 8F acts on the center 101b of the bush.

The reaction force is applied to the drive key 1 via the groove 101a.
00a, but as described above, the drive key 100
Since a is installed at an angle of θ, the drive key 100
A component F · sin θ of a compression reaction force that tries to push up the bush 101 along a is generated. The bush 101, that is, the movable scroll member 200, is
Attempts to revolve at a radius larger than the initial orbital radius RI. Thereby, even if there are some errors in the shapes of the scrolls of the movable scroll member 200 and the fixed scroll member 300, the orbital radius is automatically adjusted until the scroll of the movable scroll member 200 comes into contact with the scroll of the fixed scroll member 300. The revolving motion is performed while increasing the size. Therefore, a contact line between the scroll members 200 and 300 can be reliably formed, the degree of sealing of the sealed space is increased, and the performance of the compressor is improved.

The bush 101 by the above-described component force F · sin θ
9 and FIG. 10 show the increase in the orbital radius due to the bush movement. Bush 1
01, that is, the force of pressing the scroll of the movable scroll member 200 against the scroll of the fixed scroll member 300, appropriately sets the magnitude of θ as can be seen from the formula of F · sin θ. By doing so, it can be optimized. That is, when θ is increased in the range of 0 ° to 90 °, the component force, that is, the sealing force between the spiral bodies can be increased. However, when the sealing force is excessive, the mechanical loss of the compressor increases, and the disadvantage that the consumed horsepower is large occurs. As a result of experiments and studies conducted by the present inventors,
It has been found that if θ is set between 30 ° and 60 °, a sufficient sealing force can be obtained even under various operating conditions.

Further, as is apparent from the equation F · sin θ, the sealing force also depends on the magnitude of the compression reaction force F. Then, the compression reaction force F is determined depending on the operating state of the compressor.
And, since there is a monotonically increasing function relationship with the pressure P of the sealed space between the two scrolls, the pressure P inside the compressor is under the operating condition where the heat load is large and the rotation speed of the compressor is low. The compression reaction force F also increases, and as a result, the sealing force F · sin θ also increases. As described above, since the sealing force F · sin θ increases as the pressure P inside the compressor increases, that is, as the differential pressure between the sealed spaces increases, the above θ is set to an appropriate value. A very reasonable mechanism is that the sealing force increases or decreases according to the operating conditions and pressure conditions.

In order to determine the sealing force F · sin θ, in addition to the angle θ and the compression reaction force F, the movable scroll member 2
Although there is a centrifugal force due to the orbital motion of the self 00, this can be ignored because it is completely canceled by the balance weight 102 integrally attached to the bush 101 described above. FIG. 11 shows the positional relationship between the driving mechanism and the scroll member, the pressure P of the sealed space, the compression reaction force F, and the sealing force of the above operation.

Next, referring to FIG. 8 and FIG.
The regulation of the movement amount of No. 01 will be described. As described above, the bush 101 is movable along the longitudinal direction of the drive key 100a. However, the rotation may be stopped during operation, for example, due to disengagement of the magnet clutch. At this time, due to the inertial force of each part, the bush 101 moves so as to slide down along the drive key 100a. As a result, the spiral body of the movable scroll member 200 violently collides with the spiral body of the fixed scroll member 300, and the descending / returning is stopped. If this is allowed, not only the collision sound between the two scrolls may be generated as an unusual sound at the time of stop, but also a situation where the scroll member of the scroll member is damaged may be caused. Conventionally, a separate locking mechanism had to be provided to prevent these problems. However, if the above-described configuration is adopted, there is no need to provide any new mechanism.
In the example shown in FIG. 8, the longitudinal dimension of the groove 101a is the driving key 1
However, if the dimension is selected appropriately, the drive key 100a and the groove 101a can be formed before the spiral members of the scroll member collide with each other when the bush 101 is lowered. Are combined, the movement of the bush 101, that is, the movable scroll member 200 is restricted, and the collision between the scrolls of the scroll member can be prevented.

If the longitudinal dimension of the groove is sufficiently large within a range that does not lead to collision between the spirals, the spirals 200 and 3 are prevented from being occasionally compressed during startup.
00 is allowed to rotate without contact, and a special relief valve for liquid compression can be eliminated. As described above, there is an advantage that only the mechanism for adjusting the orbital radius can function as a relief mechanism for regulating the moving range of the movable scroll member and for compressing the liquid.

In the present invention, in order to restrict the movement and tilting of the bush 101 in the shaft axis direction, the drive key 1 is used.
A locking means such as a circlip 900, which is conventionally known, as shown in FIG.
The circlip 900 is attached to the tip of the drive key 100a with the open end 901 opened as is well known. In the attached state, the locking surface 902 comes into contact with the end face 101f of the bush 101, and the axial movement between the drive key 100a and the bush 101 is restricted. Thereby, the bush 101 can be prevented from tilting.

As described above, in the compressor of the present embodiment, the drive key 100a provided at the end of the shaft 100 at an angle of θ in the direction opposite to the rotation direction is fitted to the drive key 100a, and Since the movable scroll member 200 is driven by using the bush 101 having the groove 101a having a dimension larger than the longitudinal dimension of the drive key, a pressing force at the contact line between the two spiral bodies is required due to the compression reaction force of the refrigerant gas. And it is obtained automatically enough to reliably form the contact line and to ensure the sealing.

Further, since the bush 101 is movable along the longitudinal direction of the driving key 100a, even if the pitch or thickness of the spiral body changes due to a dimensional error in the spiral body shape, it is automatically responded to the change. By adjusting the orbital radius, the contact line can also be reliably formed, a seal can be secured, and accurate movement can be performed. Without adding another mechanism, it is possible to prevent collision between the scrolls due to the return of the movable scroll member 200 when the compressor is stopped, thereby preventing damage to the scrolls. It also has a relief mechanism that prevents high pressure during liquid compression.

In the above embodiment, the drive key 100a is configured to be eccentric with respect to the central axis of the shaft 100. However, the fitting groove 101a of the bush 101 is eccentric with respect to the central axis of the bush 101. It goes without saying that the same operation and effect can be obtained even if this is done.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the compressor of the present invention.

FIG. 2 is a perspective view illustrating a shaft and a bush illustrated in FIG. 1;

FIG. 3 is a front view of a drive unit of the shaft in the embodiment of FIG. 1;

FIG. 4 is a side view of the shaft of FIG. 3;

FIG. 5 is a front view of the bush in the embodiment of FIG. 1;

FIG. 6 is a front view as viewed from the right direction in FIG. 5;

7 is a sectional view taken along line VII-VII in FIG.

FIG. 8 is a mechanical explanatory diagram of a force acting on a bush in the embodiment of FIG. 1;

9 is a diagram illustrating a direction in which a bush moves by the action of the force in FIG.

FIG. 10 is a schematic diagram illustrating an increase in the orbital radius after the bush moves as shown in FIG. 9;

FIG. 11 is a diagram illustrating a mechanical and relative positional relationship between a contact line between a bush and a movable scroll and an internal pressure in the embodiment of FIG. 1;

FIG. 12 is a view showing a conventional circlip, and FIG.
12A is a front view thereof, and FIG. 12B is a cross-sectional view taken along line (b)-(b) of FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 shaft 100a drive key 101 bush 101a groove 102 balance weight 200 movable scroll member 300 fixed scroll member 400 front housing 500 rear housing 600 detent mechanism 700 bearing 800 shaft seal 900 circlip

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Makoto Hamasa 1-1-1 Showa-cho, Kariya-shi, Aichi Japan Inside Denso Co., Ltd. (56) References JP-A-2-176179 (JP, A) JP-A-62- 162786 (JP, A) Really open 61-62201 (JP, U)

Claims (3)

(57) [Claims] 1. A fixed scroll member having a spiral body formed on an end plate, and a spiral body formed on an end plate, and meshes with the fixed scroll member at a shifted center. (C) a shaft that rotates upon receiving a driving force; and (d) a center of the shaft end portion offset from the center of the shaft by the radius of the orbital motion of the movable scroll member. (E) a bush that is centered and provides revolving motion to the orbiting scroll member; and (e) a rotation preventing mechanism that allows only orbiting of the orbiting scroll member and prevents rotation. Due to the orbital motion, the closed space between the movable scroll member and the fixed scroll member moves toward the center of the spiral body while reducing the volume, and the fluid in the closed space moves. The scroll compressor condensation takes place, are engaging portion formed with said bush for receiving a revolution drive force while permitting rotation of the bushing to the end plate (g) the movable scroll member, (H) The bush has a groove having a rotation transmitting surface.
Provided through said bushing, the said shaft end portion (i) abuts against the rotation transmission surface
A drive key having a shape having a surface is provided. (J) The groove of the bush is
In the direction of its movement so that it can move along the
With a predetermined gap from the drive key,
The drive key with a small clearance
Fitted in, (k) at the tip of the SL drive key, the axial direction of the bush
That locking means for restricting movement to
Features compressor. (A) a housing having a suction port and a discharge port; and (b) a shaft having a drive key rotatably supported by the housing and having at least one rotation transmitting surface at an end. (C) a rotation that fits with the drive key with a predetermined gap in the direction of movement and a small clearance in the width direction so that the drive key can move along the rotation transmission surface of the drive key. A bush having a through groove having a transmitting surface; (d) a movable scroll member rotatably engaged with the bush and revolving within the housing; (e) engaging with the movable scroll member; A fixed scroll member forming a closed space between the movable scroll member and the movable scroll member; and (f) moving the bush in the axial direction at the tip of a drive key of the shaft. Compressor, characterized in that arranged locking means for regulating. 3. The compressor according to claim 1, wherein said locking means is a circlip.