JPH05231358A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To provide a scroll type compressor excellent in durability further with ability to operate at a high speed with a simple constitution by constituting a shaft so as to transmit only a motion of rotating around the shaft relating to a column-shaped protrusion of a movable scroll member through an eccentric pin and a balance weight. CONSTITUTION:Both fixed and movable scroll members 3, 4 are housed to be meshed with each other in the insides of front and rear housings 1, 2. A shaft 6 having an eccentric pin 601 is rotatably supported to the front and rear housings 1, 5 On the other hand, an eccentric hole 702 for inserting the eccentric pin 601 and a large diametric hole 701 for inserting a column-shaped protrusion 402 of the movable scroll member 4 are formed in a balance weight 7. Further, an on-own axis-rotation impeding and thrust supporting mechanism 8 is engaged with the movable scroll member 4. In the above constitution, the shaft 6 is constituted so as to transmit only a motion of revolving around the shaft relating to the column-shaped protrusion 402 of the movable scroll member 4 through the eccentric pin 601 and the balance weight 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary positive displacement fluid compressor, and in particular, a pair of scroll members each having a spiral structure are superposed so as to be engaged with each other at different angles. The present invention relates to a so-called scroll-type compressor in which the fluid pocket formed in (1) moves toward the center by the relative circular orbital motion of these scroll members, and the volume of the fluid pocket is reduced to compress the fluid.

[0002]

2. Description of the Related Art Such scroll type compressors are disclosed in many patents and documents including US Pat. No. 801,182, and their operating principles are well known.
In a scroll compressor, one or more fluid pockets are formed between the line contact parts of a pair of spiraling bodies that mesh with each other, and the line contact parts are formed on the surface of the spiral body by the relative circular orbital motion of the scroll member. Since the fluid pocket reduces the volume and compresses the fluid by moving along the center direction, it is necessary to sufficiently secure the sealing force of the line contact portion. However, if the contact force is increased in order to secure the sealing force, abrasion will occur on the contact surface between the spiraling bodies. For this reason, the contact force between both spiraling bodies must be set to an appropriate value that does not cause wear due to contact while providing the necessary sealing property. Also, when driving with a fixed crank radius,
This contact force is not always kept constant due to the dimensional error in manufacturing the spiraling body, and the manufacturing becomes difficult if the dimensional error is reduced.

In order to solve these problems, in the conventional scroll type compressor, the power transmission mechanism is usually constructed as described in Japanese Utility Model Laid-Open No. 57-83291. .. That is, the power transmission mechanism is a shaft that receives power, an eccentric bush that interlocks with the shaft, a balance weight attached to the bush,
It is composed of rivets for attaching balance weights, radial bearings for connecting the bush and movable scroll, and so on. The bush rotatably supports a boss in which a radial bearing is press-fitted inside, which is formed on the surface of the movable scroll opposite the spiral body, and the shaft drive pin rotates in the eccentric hole of the bush. It is fitted freely. Further, a balance weight is attached to the bush by rivets in order to cancel the dynamic imbalance of the movable scroll member.

[0004]

In the structure of such a conventional scroll type compressor, the movable scroll side plate inside the boss is a dead end, and the lubricating fluid inside the boss does not flow when the bush is inserted. It becomes stagnant and it is difficult for the fluid to flow. Therefore, the radial bearing inside the boss portion is liable to have poor lubrication, which leads to flaking of the bush surface and damage to the radial bearing, which causes the durability of the compressor to be reduced. Also, since the radial bearing rolls on the surface of the bush under a large load, it is necessary to polish the bush.For convenience of processing, the bush and the balance weight are cut separately, and the bush is polished. After applying, it is necessary to integrate them by means such as rivets. However, when the compressor is rotated at a high speed, the centrifugal force acting on the balance weight F = mrω ² (F; centrifugal force, m; balance weight mass, r; distance from balance shaft center of gravity to shaft center, ω; angular velocity) Is an extremely large value because it increases in proportion to the square of the rotation speed. Therefore, there is also a problem that breakage occurs due to rivet breakage or the like at the joint portion.

An object of the present invention is to solve these problems of the conventional scroll type compressor and to provide a scroll type compressor excellent in durability and capable of high speed operation. Still another object of the present invention is to provide a scroll compressor having a small number of parts, a simple structure, easy manufacture, and miniaturization.

[0006]

As a means for solving the above-mentioned problems, the present invention comprises a compressor housing having an intake port and an exhaust port, and a spiral housing formed on a side plate. A fixed scroll member fixed inside, a movable scroll member formed of a spiral body formed on a side plate so as to be engaged with the fixed scroll member while shifting the center, and rotatably supported in the compressor housing. And a shaft having a drive pin at a position eccentric to the shaft center, an eccentric hole for receiving the drive pin of the shaft, and a cylindrical protrusion axially provided on the side plate of the movable scroll member. Both of the large axial holes that are open at both ends and that are received via bearings are assembled in the shaft. A balance weight that is opened at a position eccentric to the center and a rotation prevention and thrust support mechanism that engages with the side plate of the movable scroll member are provided, and the shaft has the drive pin and the balance weight. Provided is a scroll-type compressor, which is configured to transmit only the revolution movement to the cylindrical projection of the movable scroll member via the.

[0007]

By providing the movable scroll member, which engages with the fixed scroll member with its center displaced, in a revolving motion without rotation, a fluid pocket formed between the spiral members of these scroll members is formed from the outer peripheral portion to the central portion. The basic operation as a scroll compressor is to compress the fluid sucked from the suction port and discharge it to the discharge port by utilizing the fact that the volume of the fluid pocket is reduced along with the movement to the discharge port. In the present invention, the eccentric hole for receiving the drive pin of the shaft and the axial direction of the side plate of the movable scroll member are provided at the eccentric position viewed from the shaft center of the shaft on the balance weight in the assembled state. The large diameter hole that receives the cylindrical protrusion through the radial bearing is opened. As to release, it is provided through the balance weight.

Therefore, the large diameter hole allows the lubricating oil to flow from the opening at one end to the opening at the other end, the radial bearing provided therein is sufficiently lubricated, and the largest load in the scroll compressor is provided. There is no risk of damaging the acting radial bearings due to poor lubrication. Further, the columnar projections provided on the side plate of the movable scroll member in the axial direction are driven so as to revolve through the radial bearings by the large-diameter holes provided in the integral balance weight. Unlike a compressor, it is not driven by an integrated bush that is inserted into a boss formed on the side plate of the movable scroll member and is attached to a balance weight, so the drive mechanism is robust and the structure is Easy and miniaturized.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a scroll type compressor according to an embodiment of the present invention comprises a front housing 1 made of aluminum or an aluminum alloy and a rear housing 2 having a cup-shaped portion 202. It has a housing. The front housing 1 has a concentric internal shape for inserting the shaft 6, and an annular protrusion 102 concentric with the internal shape is formed on the back surface. The cup-shaped portion 202 of the rear housing 2 has its opening fitted to the annular protrusion 102 of the front housing 1 and is fixed by means such as a bolt. In addition, the O-ring 13 is sandwiched between the joints to perform sealing.

A disk portion 60 formed on the inner end of the shaft 6.
5, the drive pin 601 is provided at a position deviated from the center so as to project in the axial direction, as is apparent from FIG. The shaft 6 is rotatably supported by a ball bearing 10 provided inside the front housing 1 with a disc portion 605 and a step portion 606 formed at the ends thereof. The front housing 1 is also
A sleeve 10 extending forward so as to surround the shaft 6.
Have one. The sealing mechanism 11 is inserted inside the front housing 1 and seals the shaft 6. An electromagnetic clutch (not shown) is mounted on the outer surface of the sleeve 101, and receives the rotation of an external drive source (for example, a vehicle running engine) via a belt and transmits the rotation to the shaft 6.

In the cup-shaped portion 202 whose opening is closed by the front housing 1, a fixed scroll member 3 composed of a spiral body 301 and a side plate 305, a movable scroll member 4 composed of a spiral body 401 and a side plate 405, and a movable scroll drive. A mechanism (described in detail later) and a rotation-preventing / thrust-supporting mechanism 8 for the movable scroll member 4 are provided. The fixed scroll member 3 is a spiral body 30.
In the state where the surface opposite to 1 is in contact with the end surface of the cylindrical support portion 201 of the rear housing 2, it is fixed by a bolt (not shown) penetrating the cylindrical support portion 201 from the outside. An O-ring 14 seals between the outer peripheral surface of the fixed scroll member 3 and the inner surface of the cup-shaped portion 202. Therefore, the inside of the cup-shaped portion 202 is divided into a front chamber 205 and a rear chamber 206.

A movable scroll member 4 is arranged in the front chamber. The movable scroll member 4 is composed of a side plate 405 and a vortex body 401 fixed to one surface of the side plate 405.
Fluid pockets 20a, 20b, 20c, and 20d are formed between them. The movable scroll member 4 is connected to a drive mechanism which will be described later, and is configured to revolve on a circular orbit having a radius R ₀ by the rotation of the shaft 6, whereby the fluid pocket compresses the fluid. Is done. At this time, the rotation (rotation) of the movable scroll member 4 is blocked by the rotation blocking mechanism 8. The radius R ₀ of the circular orbit is generally [(pitch of spiral body) − (wall thickness of spiral body) ×
2] ÷ 2.

Next, the drive mechanism of the movable scroll will be described with reference to FIG. 2 in addition to FIG. Front housing 1
A disc portion 605 is formed at the inner end of the shaft 6 supported by the ball bearing 10 therein, and the drive pin 601 is provided at a position deviated from the center so as to project in the axial direction. As described above.

On the other hand, the side plate 405 of the movable scroll member 4
The cylindrical protrusion 4 on the surface opposite to the spiral body 401.
02 is formed. Further, the ring 5 has a cylindrical shape or a shape close thereto, and is fixed onto the cylindrical projection 402 by means such as press fitting. The material of the ring 5 is
For example, high carbon steel, bearing steel, etc. that have undergone quenching treatment, or alloy steel that has undergone carburizing and quenching treatment, etc.
Use a material with high hardness.

As shown in FIG. 2, the balance weight 7 has an appropriate thickness for canceling the moment of a member that is eccentric with respect to the center of the shaft 6, such as the movable scroll member 4, and has a columnar shape and a semicircular shape. It has a fan shape or a shape that is a combination of shapes close to it, and has a large diameter hole 701 penetrating in the axial direction and an eccentric hole 702 penetrating in the axial direction at a position deviated from the center of rotation. In the large-diameter hole 701, the ring 5, that is, the cylindrical projection 402 of the movable scroll member 4 is rotatably supported via the radial bearing 9. The drive pin 60 is provided in the eccentric hole 702.
1 is rotatably fitted and is prevented from coming off by a circlip or the like.

The center O _{S of the} shaft 6, the large diameter hole 701 and thus the center O _{C of the} ring 5, the eccentric hole 702 and therefore the drive pin 6
The positional relationship of the center O _D of 01 is as shown in FIG. That is, in this state, the distance between O _S and O _C is selected as the orbital radius R _O described above, and the eccentric distance ξ of the drive pin 601 is set.
₁ and the eccentric distance ξ ₂ of the eccentric hole 702 are
When the two are fitted into the eccentric hole 702, the centers O _{D of} the both are
O with respect to a line perpendicular to O _C to a line connecting the street O _C and O _S
S is on the same side as the line connecting O _C and O _S
It is selected so that it can be assembled so as to be in a position delayed in the rotation direction of the shaft 6 (direction of arrow A shown in FIG. 3).

Since the drive mechanism is constructed as described above, the center O _C of the large diameter hole 701 can move on an arc having a radius ξ ₂ centered on the drive pin 601 and hence the center O _D. Become. That is, when the shaft 6 rotates, the balance weight 7 is pushed by the drive pin 601 and the large diameter hole 7
The center O _{C of} 01 acts to separate from O _S, and the surface of the vortex body of the movable scroll member 4 comes into contact (line contact) with the surface of the vortex body 301 of the fixed scroll member 3.
Thus the center of the movable scroll member 4 is orbital motion with a radius R _O around the center O _S of the shaft 6 (revolution). At this time, the movable scroll member 4 is rotated by the rotation preventing mechanism 8
Since the rotation is blocked by, it does only the orbital motion and does not rotate. On the other hand, the balance weight 7 rotates at the same speed as the rotation of the main shaft. This orbital movement of the movable scroll member 4 causes the fluid pockets 20a ...
The fluid d is compressed by the inward movement of d and the reduction of its volume. At this time, in order to supply the fluid to be compressed to the front chamber 205, the cup-shaped portion 202 is provided with a fluid suction port (not shown). On the other hand, in order to discharge the compressed fluid to the rear chamber 206, the discharge hole 302 and the discharge valve 12 are formed in the central portion of the side plate 305 of the fixed scroll member 3, and the rear chamber 206 is connected to the external fluid circuit. The port 203 is provided in the rear housing 2. Incidentally, the line contact portions of the spiral body 301 and 401 is always the central axis O _S
To be on the plane including the O _C.

Balance having such an eccentric hole 702
Drive the movable scroll member 4 using the weight 7.
And the reaction force of fluid compression, both spiraling bodies 301 and 40
The pressing force at the line contact part of 1 is automatically obtained.
A seal for the fluid pockets 20a-20d is ensured. Change
At the center O of the large hole 701_CIs the center O of the drive pin 601
_DSince it can rotate around, for example, the spiral body 30
Spiral pitch or eddy due to dimensional error of 1 or 401
Even if the thickness of the sowing body changes, O_CO _SDistance
Can change. Therefore, such dimensional error
Even if there is, the movable scroll member 4 performs a smooth motion.
Suitable for line contact with fixed scroll member 3
It is possible to obtain a sufficient pressing force. The balance weight 7 is movable
Circular orbital motion of scroll member 4 and radial bearing 9
This centrifugal force is provided to cancel the centrifugal force due to
Is canceled by the centrifugal force acting on the balance weight 7.
Be done.

The radial bearing 9 has a large diameter hole 7
Since 01 penetrates in the axial direction, it is open in the front and back as shown in FIG. Therefore, unlike the conventional case, there is no concern that the lubricating oil will stagnate in the bearing portion and cause poor lubrication, and a good lubricating state can be obtained by the circulation of the lubricating oil, and the durability of the compressor can be improved. Further, since the cylindrical projection 402 of the movable scroll member 4 is supported by the radial bearing 9 mounted in the large diameter hole 701 of the balance weight 7 via the ring 5 or not, it is movable with respect to the balance weight 7. It is not necessary to separate them from the support portion of the scroll member 4 and integrate them with rivets or the like. The conventional scroll type compressor shown in FIG. 8 uses a component in which the bush 7a and the balance weight 7b are integrated by rivets or bolts 7c, and the radial bearing 9 is a boss formed on the side plate 405 of the movable scroll member 4. Since it is inserted into the large diameter hole 407 of the portion 406, the flow path of the lubricating oil of the radial bearing 9 is a dead end. Therefore, the radial bearing 9 is apt to have poor lubrication. In addition, there is a concern that the rivet or the like may be cut off and destroyed due to the centrifugal force of the balance weight 7b when it is operated at a high speed, but in the embodiment of the present invention, such concern is eliminated,
It is possible to improve the reliability when the high speed rotation or the operation of repeating ON-OFF is performed. Further, since the number of parts is small and the structure is simple, the manufacturing is easy, and the wall thickness of the rivet joint is unnecessary, so that it is possible to reduce the size in the axial direction.

On the other hand, the balance weight 7 has a protrusion 703 on the shaft 6 side. Further, a concave portion 602 is formed at the inner end of the disc portion 605 of the shaft 6, and the projection 703 is received therein. The balance weight 7 has a recess 602 and a protrusion 70 centered on the eccentric hole 702.
Rotation is allowed by the amount of play of 3. Therefore, even when the compressor is turned on or off or the rotational speed changes, it is possible to prevent the spiral body 401 of the movable scroll member 4 from colliding with the spiral body 301 of the fixed scroll member 3 due to inertial force. it can.

FIG. 4 shows another embodiment in which the positional relationship among the center O _S of the shaft 6, the center O _D of the drive pin 601, and the center O _C of the large diameter hole 701 is different from the embodiment shown in FIG. .. In the embodiment of FIG. 4, the distance between the center O _{S of the} shaft 6 and the center O _C of the large diameter hole 701 is selected to be the orbital radius R _O described above, the eccentric distance ξ ₁ of the drive pin 601 and the eccentric hole 702.
Eccentricity xi] ₂ of, when the driving pin 601 is fitted into eccentric hole 702, center O _D of both, through the O _C O _C and O
_{A position} that is on the opposite side of O _S with respect to the line orthogonal to the line connecting _S and that is advanced in the rotation direction of the shaft 6 (direction of arrow A shown in FIG. 4) from the line connecting O _C and O _S. Selected to be assembled as in. Also in the above-mentioned positional relationship, the same effect as in the case of the positional relationship of the embodiment shown in FIG. 3 can be obtained.

FIG. 5 shows another embodiment different from the embodiment shown in FIG. 1 in the related structure of the eccentric hole and the drive pin.
That is, an eccentric hole 603 is provided at the inner end of the disc portion 605 of the shaft 6 at a position deviated from the center, and the balance weight 7 has a drive pin 703 at a position deviated from the center on the shaft 6 side. Are provided so as to project. A drive pin 703 is fitted in the eccentric hole 603 and is rotatably supported. Also in this embodiment, the same operational effects as the embodiment shown in FIG. 1 can be obtained.

In the above-described embodiment, as shown in FIG. 2, the concave portion 602 for preventing the movable scroll member 4 from colliding with the fixed scroll member 3 is the disc portion 6 of the shaft 6.
Although the concave portion 602 is provided at the inner end of 05 and the projection 703 that engages with the concave portion is provided on the balance weight 7, the projections are provided on the disk portion 605 side of the shaft 6 by reversing the concave-convex relationship. A recess may be provided on the balance weight 7 side.

The ring 5 shown in FIG. 1 and the like is integrated with the cylindrical projection 402 provided on the side plate 405 of the movable scroll member 4, but it corresponds to this ring and the rotation preventing and thrust supporting mechanism 8 as well. FIG. 6 shows an embodiment in which the inner race of FIG. The brim portion 502 of the ring 501 serves as a race of the rotation preventing mechanism 8. The other structure is similar to that of the embodiment shown in FIG. With the above configuration, the embodiment of FIG. 6 can reduce the number of parts and increase the rigidity of the cylindrical protrusion 402 formed on the movable scroll member 4, and the deformation of the movable scroll member 4 and the tilt associated therewith. Can be reduced, so that the sealing properties of the fluid pockets 20a, 20b, 20c, 20d, 20d, 20d, 20c, 20d, 20d, 20c, 20d, 20d, 20c, 20d, 20c, 20d, 20c, 20c, 20d, 20c, 20d, 20c, 20d, 20c, 20d, 20c, 20d, 20e, 20d, 20d, 20d, 20b, 20m, 10d, and 10s use is improved. Needless to say, the present invention is not limited to the structure of the illustrated embodiment, and various design changes can be made.

[0025]

The scroll type compressor of the present invention has a simple structure and is robust and does not cause poor lubrication. Therefore, it has high durability and is suitable for high speed rotation.

[Brief description of drawings]

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

FIG. 2 is a development view showing an embodiment of a drive mechanism that is a main part of the compressor of the present invention.

FIG. 3 is a conceptual diagram illustrating the operation of an embodiment of a drive mechanism.

FIG. 4 is a conceptual diagram illustrating the operation of another embodiment of the drive mechanism.

FIG. 5 is a sectional view showing another embodiment of the compressor of the present invention.

FIG. 6 is a sectional view showing still another embodiment of the compressor of the present invention.

FIG. 7 is an enlarged sectional view showing an embodiment of the drive mechanism of the compressor of the present invention.

FIG. 8 is a cross-sectional view illustrating a drive mechanism of a conventional scroll compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Front housing 2 ... Rear housing 3 ... Fixed scroll member 4 ... Movable scroll member 5 ... Ring 6 ... Shaft 7 ... Balance weight 7a ... Bushing (prior art) 8 ... Rotation prevention and thrust support mechanism 9 ... Radial bearings 20a-20d ... Fluid pockets 301, 401 ... Spiral bodies 305, 405 ... Side plates 402 ... Cylindrical projections 406 ... Boss portion (prior art) 501 ... Collared ring 601 ... Drive pin (eccentric pin) 602 ... Recessed portion 605 ... Disc portion 701 ... Large Diameter hole 702 ... Eccentric hole 703 ... Protrusion

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kazuhide Uchida 14 Iwatani, Shimohakaku-cho, Nishio-shi, Aichi Japan Auto Parts Research Institute (72) Inventor Yasuhiro Oki 1-1-chome, Showa-cho, Kariya city, Aichi Within Nippondenso Co., Ltd.

Claims (1)

[Claims] 1. A compressor housing having an intake port and an exhaust port, a fixed scroll member formed of a spiral body formed on a side plate and fixed in the compressor housing, and a spiral body formed on the side plate. And a movable scroll member incorporated so as to engage with the fixed scroll member while shifting the center, and a shaft rotatably supported in the compressor housing and having a drive pin at a position eccentric to the shaft center. An eccentric hole for receiving the drive pin of the shaft and a large-diameter hole in the axial direction at both ends for receiving a cylindrical projection axially provided on the side plate of the movable scroll member via a radial bearing. A balance weight that is opened at a position eccentric to the shaft center in the assembled state, A rotation preventing and thrust supporting mechanism engaged with the side plate of the movable scroll member, and the shaft only revolves to the cylindrical projection of the movable scroll member via the drive pin and the balance weight. A scroll type compressor characterized in that it is configured to transmit.