JPS6325345Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotary positive displacement fluid compressor, and particularly relates to a pair of scroll members each having a spiral body fixed on a side plate. By the relative circular orbital movement of one scroll member,
This invention relates to a scroll type compressor that compresses fluid by moving a fluid pocket formed between both spiral bodies to the center, thereby reducing its volume. Such a scroll compressor has been disclosed in many patents and documents including US Pat. No. 801,182, and its operating principle has been well known for a long time.

Incidentally, in such a scroll type compressor, fluid compression is performed by reducing the volume by moving fluid pockets formed in both spiral bodies. This fluid pocket is formed between both spiral bodies by line contact between the side wall surfaces of both spiral bodies and contact between the axial tip end surface of each spiral body and the surface of the other side plate. Furthermore, these contact portions are slidably moved by the circular orbital motion of one of the scroll members, resulting in the movement of the pocket for fluid compression as described above.

Therefore, in order to reliably compress the fluid, it is necessary to reliably seal the sliding contact portion.
Therefore, in order to reliably seal the sliding contact between the axial end surfaces of both spiral bodies and the surface of the opposing side plate, a sealing element made of a soft material such as Teflon is installed on the axial end surfaces of both spiral bodies. A structure in which a tip seal (hereinafter referred to as a tip seal) is provided and the tip seal is pressed against the side plate surface of an opposing scroll member is disclosed in U.S. Pat.
117304). However, even if such a tip seal is used to ensure a reliable seal, wear due to sliding between the tip seal and the side plate often poses a problem. In particular, when both scroll members are made of aluminum or aluminum alloy to reduce weight, the soft aluminum spiral body side walls slide against each other, and the soft aluminum side plates and soft wear-resistant tip seals slide against each other. As a result, severe wear occurs on the sliding surfaces and a large amount of wear powder is generated, which can invade and damage bearings used inside the compressor, and can clog filters and expansion valves in the refrigeration circuit. It was the cause of this. Furthermore, wear and scratches on the surface of the side plate may cause incomplete sealing at the sliding contact area between the side plate and the tip seal disposed on the tip surface of the spiral body facing the side plate, reducing compression efficiency. It was on.

By the way, in order to suppress sliding wear on the side walls, side plates, and ends of the spiral winding body of both scroll members, it is disclosed in JP-A-55-81295 that these parts are treated with a hard coating such as alumite treatment. . By applying such a hard coating treatment, in principle, the sliding wear of these parts can be suppressed, and the sliding wear of the side plate with the tip seal can also be suppressed. However, when hard coating treatment is applied to both scroll members, there is a problem in that the sliding surfaces of both scroll members are difficult to fit together due to their hard surfaces, and therefore machining with high dimensional accuracy is required. In the case of using a tip seal as described above, since the tip seal is soft, it easily conforms to the side plate, but the side walls of the spiral body do not conform to each other, and if there is a dimensional error, these side walls will collide with each other, resulting in partial hard coating. Damage may occur, and damage may occur at even one location, which may lead to further damage to other parts, which is an inconvenience. Therefore, treating the surfaces of both scroll members with a hard coating is not a practical solution, considering that it is extremely difficult to process a spiral body with high side surface accuracy. .

In view of the above points, the present invention manufactures a scroll member made of aluminum or aluminum alloy,
Furthermore, in a scroll compressor in which a tip seal is placed on the end face of the spiral body, a simple structure prevents the occurrence of wear and scratches on the scroll member, thereby maintaining the seal of the fluid pocket for a long period of time. An object of the present invention is to provide a scroll type compressor.

In this invention, a pair of scroll members each having a spiral body fixed on a side plate are stacked so that the spiral bodies are angularly shifted from each other and engage with each other, and the relative circular orbital movement of one scroll member is used. Then,
A scroll-type compressor that compresses fluid by moving a fluid pocket formed between both spiral bodies to the center and thereby reducing its volume, the scroll compressor having a fluid pocket formed between the spiral bodies of both scroll members. In a scroll compressor in which a sealing element is attached and both scroll members are made of aluminum or aluminum alloy, the surface of the spiral body of one scroll member and the surface of the side plate to which the spiral body is attached are hard. The scroll type compressor is coated and characterized in that a spiral hard wear-resistant plate is fitted between the spiral bodies of the other scroll member.

According to the present invention, both scroll members are made of aluminum or aluminum alloy, and only one scroll member is hard surface treated, so that the side surface of one spiral body is a hard surface, and the surface of the other spiral body is a hard surface. Since it is soft, even if the dimensional accuracy is not very high, the sides of both spiral bodies become familiar with each other with use, reducing friction and suppressing sliding wear. The tip seal attached to the scroll member that is not treated with a hard surface slides on the side plate surface of the scroll member that is treated with a hard surface,
Similarly, after getting used to it, wear on the tip seal is suppressed. Furthermore, since a spiral-shaped hard wear-resistant plate is provided between the tip seal attached to the hard-surface-treated scroll member and the scroll member that is not hard-surface-treated, this hard wear-resistant plate protects the surface of the side plate of the scroll member that is not subjected to hard surface treatment from sliding with the tip seal, and the tip seal conforms to the hard surface plate, reducing sliding wear.

Thus, according to the present invention, a scroll type compressor can be obtained in which both scroll members as a whole have almost no sliding wear.

Embodiments of the present invention will be described in detail below with reference to the drawings.

Referring to FIG. 1, the illustrated compressor 1 has a compressor housing 10 consisting of a cylindrical portion 11, a front end plate 12 installed at its front end, and a rear end plate 13 installed at its rear end. There is. The front end plate 12 has a center hole in which a main shaft 15 is mounted with a ball bearing 14.
is rotatably supported. The front end plate 12 also has a sleeve portion 16 that extends forward so as to surround the main shaft 15, and a shaft seal assembly 17 is incorporated therein. A pulley 19 is rotatably supported on the outer surface of the sleeve portion 16 by a bearing 18, and
An electromagnet 20 is fixed. On the other hand, an armature plate 21 is elastically supported on the end of the main shaft 15 that protrudes from the sleeve portion 16. That is, the pulley 19, the electromagnet 20, and the armature plate 21 constitute an electromagnetic clutch, which allows an external drive source (for example, an automobile engine) to be connected to the clutch.
The rotation is transmitted to the pulley 19 via the belt, and by energizing the electromagnet 20, the armature plate 21 is attracted to the pulley 19, thereby transmitting the rotational force to the main shaft 15. The front end plate 12 has a front end of the cylindrical part 11,
It is fixed with, for example, a bolt (not shown) so as to close the opening, and is sealed with an O-ring 22. Rear end plate 1
3 has a suction chamber 24 and a discharge chamber 25 formed therein by a partition wall 23, and also includes a fluid suction port 26 and a fluid discharge port (not shown) communicating with the suction chamber 24 and discharge chamber 25, respectively. There is. This rear end plate 13 has bolts and nuts 27
It is attached to the rear end of the cylindrical portion 11 by a screw.
A side plate 281 of the fixed scroll member 28 is held between the rear end plate 13 and the cylindrical portion 11. Note that 2 and 3 are gaskets to prevent fluid leakage.

The fixed scroll member 28 consists of a side plate 281 and a spiral body 282 fixed on one side of the side plate 281. Since the side plate 281 is held between the rear end of the cylindrical portion 11 and the rear end plate 13 as described above, the rear end opening of the cylindrical portion 11 is closed by the side plate 281. The spiral body 282 is arranged in a chamber 29 inside the cylindrical portion 11 . The side plate 281 connects the internal chamber 29 of the cylindrical portion 11 and the suction chamber 2.
4, and a discharge hole 284 for discharging the compressed fluid in the fluid pocket at the center into the discharge chamber 25.

A movable scroll member 30 is disposed within the chamber 29 . The movable scroll member 30 has a side plate 30
1 and a spiral body 302 fixed to one side thereof, and the spiral body 302 is connected to the spiral body 282.
They are interlocked with an angular offset of 180° to form a fluid pocket between the two spiral bodies. The spiral bodies 282, 302 have grooves formed on their respective axial end faces, into which spiral tip seals 285, 305 are fitted, thereby preventing gas leakage at the end faces of each spiral body. are doing. The movable scroll member 30 is connected to a drive mechanism and a rotation prevention mechanism, which will be described later, and is configured to revolve around a circular orbit with a radius R ₀ by the rotation of the main shaft 15. Compression of the fluid as described above is performed.

The radius R ₀ of a circular orbit is generally (pitch of the spiral body) - 2 × (wall thickness of the spiral body)
/2 is given.

Next, the drive mechanism of the movable scroll will be explained with reference to FIGS. 2 and 3 in addition to FIG. 1.

A large diameter portion 151 is formed at the inner end of a main shaft 15 supported by a ball bearing 14 on the front end plate 12 . This large diameter portion 151 is
A ball bearing 31 is installed in the front opening of the cylindrical portion 11.
is rotatably supported by. The inner ring of the ball bearing 31 is in contact with a collar 152 provided on the large diameter part 151, while the outer ring is in contact with a collar 111 provided in the front opening of the cylindrical part 11. In addition, the inner ring of the ball bearing 14 is connected to the stepped portion 15 of the main shaft.
3, and the outer ring is in contact with the front end plate 1.
It is in contact with the shoulder portion 121 of the opening of No. 2. As a result, the main shaft 15, ball bearings 14 and 31
is supported without axial wobbling.

A drive pin 154 is provided on the distal end surface of the large diameter portion 151 at a position offset from the center so as to protrude in the axial direction.

On the other hand, the side plate 301 of the movable scroll member 20
An annular boss 303 is formed on the opposite surface of the spiral body 302. In this embodiment, the center of the boss coincides with the center of the spiral of the spiral body 302. A thick disk-shaped or short-shaft shaped bush 33 is fitted into the boss 303 and rotatably supported via a needle bearing 34 . The bush 33 is integrated with a disc-shaped balance weight 33 extending in the radial direction.
1. The bush 33 also has an axial or eccentric hole 332 located off-center, into which the drive pin 154 is fitted and rotatably supported by the needle bearing 32. There is.

Center of main shaft 15 O _S , center of bush 33 O _C ,
The positional relationship between the hole 332 and the center O _D of the drive pin 154 is as shown in FIG. That is, in this state, the distance between O _S and O _C is selected to be the orbit radius R ₀ described above, and the eccentric distance ε ₁ of the drive pin 154 and the eccentric hole 3
The eccentricity distance ε ₂ of 22 means that the drive pin 154 is connected to the eccentric hole 3.
22, the center O _D of both passes through O _C and is on the opposite side of O _S with respect to the line orthogonal to the line connecting O _C and O _S , and connects O _C and O _S. It is selected so that it can be assembled in a position that is advanced from the line in the direction of rotation of the main shaft (in the direction of arrow A shown in FIG. 3).

In such a configuration of the drive mechanism, the center O _C of the bush 33 can move on a circular arc having a radius ε ₂ centered on the drive pin 154 and, therefore, its center O _D . That is, when the main shaft 15 rotates, the bush 33 is pulled by the drive pin 154, and a force is exerted to move the center O _C of the bush 33 away from O _S , causing the spiral body of the movable scroll to come into contact with the side wall of the spiral body of the fixed scroll. come into contact with Therefore, the center of the movable scroll member 30 orbits around the main shaft center O _S with a radius R ₀ . of course,
At this time, since the movable scroll member 30 is prevented from rotating by a rotation prevention mechanism described later,
It moves only in orbit and does not rotate. On the other hand, the bush rotates at the same speed as the main shaft. This orbital movement of the movable scroll member 30 moves the fluid pockets and compresses the fluid as described above. Note that the line contact portion between the spiral bodies 282 and 302 is always on the plane on which the central axes O _S and O _C lie.

A bush 33 having such an eccentric hole 332
When the movable scroll member 30 is driven using the fluid compression force, both spiral bodies 302
A pressing force at the line contact between and 208 is automatically obtained, thereby ensuring a seal of the fluid pocket. Furthermore, since the center O _C of the eccentric bush 33 is rotatable around the center O _D of the drive pin 154,
For example, even if the pitch of the spiral or the wall thickness of the spiral changes due to dimensional errors in the spirals 282 and 302, the distance between O _C and _OS can change accordingly.
Therefore, even if there is such a dimensional error, the movable scroll member 30 can perform smooth movement.

The balance weight 331 is provided to cancel the centrifugal force F ₁ caused by the circular orbit motion of the movable scroll member 30, bearing 34, and bush 33, and the centrifugal force F ₂ of the balance weight 331
F ₁ cancels out.

In addition, in the embodiment shown in FIG. 1, the centrifugal force F ₁ ,
In order to prevent the occurrence of shaft runout due to the moment due to _F2 , balance weights 35 and 36 are provided as shown in the figure.
The moment due to centrifugal force cancels the moment of centrifugal force F ₁ and F ₂ .

FIG. 4 is an exploded perspective view of the rotation prevention mechanism shown at 37 in FIG. 1, which includes a mechanism for thrust supporting the movable scroll member. Referring to the figure, this rotation prevention mechanism 37 is a fixed ring that is arranged around the boss 303 of the movable scroll member 30 and that is prevented from rotating by a pin 373 on a stepped portion 112 provided on the inner wall of the cylindrical portion 11. It has 371. The fixed ring 371 has a pair of keyways 371a and 371b extending over one diameter on an axial end face facing the movable scroll member 30. Fixed ring 371 and movable scroll member 3
A sliding ring 372 is disposed between the side plate 301 of 0 and the side plate 301 of 0. This sliding ring 372 has a pair of keys 372a, 372b extending over one diameter on the surface facing the fixed ring 371, and these keys 372a, 372b fit into the key grooves 371a, 371b of the fixed ring 371. are mated to each other. As a result, the sliding ring 372 is fixed ring 3
71 but in one direction perpendicular to the axis i.e. keyway and keys 371a-372
It is slidable in the extending direction of b.

The sliding ring 372 also has a key 3 on the shaft end surface facing the side plate 301 of the movable scroll member 30.
Keys 372c and 372d extend on one diameter 90 degrees apart from the extending direction of keys 72a and 372b. On the other hand, the side plate 30 of the movable scroll member 30
1 is a boss 3 on the surface facing the sliding ring 372.
03 has a pair of keyways (only one keyway 301a is shown in FIG. 4; the other extends on the same diameter as the keyway 301a) for receiving keys 372c and 372d. As a result, the movable scroll member 30 is prevented from rotating with respect to the sliding ring 372, but the key and the keyway 372c-
It is made slidable in the extending direction of 301a.

In this configuration of the rotation prevention mechanism 37, the movable scroll member 30 is slidable in one diameter direction together with the sliding ring 372, and is slidable alone in another orthogonal diameter direction. Therefore, although the movable scroll member 30 is prevented from rotating, that is, rotating on its own axis, it is allowed to move in two orthogonal directions, so that the above-mentioned circular orbital movement is allowed.

The sliding ring 372 has a plurality of axially perforated pockets 38 arranged at equal angular intervals (however, the key 372
(excluding the part a-372d),
A bearing ball 39 (not shown in FIG. 4) is held in each pocket 38. The bearing ball 39 has a diameter larger than the thickness of the sliding ring 372 and contacts the opposing surface of the fixed ring 371 and the opposing surface of the side plate 301. Therefore, the movable scroll member 30 is connected to the fixed ring 3 via the ball 39.
It is thrust supported on 71.

Note that the diameter of the pocket 38 only needs to be larger than the diameter of the ball 39. However, in order for the ball to always roll following the movement of the movable scroll member 30, the diameter d _p of the pocket 38 must be the sum of the radius R ₀ of the circular orbital motion of the movable scroll member and the diameter d _b of the ball. are selected to be equal to or greater than (i.e., d _p ≧ R ₀ + d _b ). If smaller than this,
If the ball does not roll, the contact points with the fixed ring and movable scroll may slide and cause damage to them. Moreover, if it is too large, the ball position may not be constant and there is a risk of wobbling.

In the scroll compressor with the above configuration, driving force from an external drive source is transmitted to the pulley via a belt (not shown), and the electromagnetic clutch 19-20-21
When the signal is transmitted to the main shaft 15 via the movable scroll member 30, the movable scroll member 30 moves on a circular orbit with a radius _R0 without rotating due to the action of the drive mechanism and rotation prevention mechanism described above. This draws fluid from the external end of the spiral into the fluid pocket formed between the movable scroll member 30 and the fixed scroll member 28. The taken in fluid is compressed as the volume decreases as the fluid pocket moves toward the center, and is discharged from the discharge hole 284 in the center into the discharge chamber 25, and then from the discharge hole (not shown) to the external fluid circuit. sent to. The fluid that has circulated through the external fluid circuit enters the suction chamber 24 through the inlet 26 and is conducted through the hole 283 into the chamber 29 where it is taken up again into the fluid pocket.

Here, the scroll members 28 and 30 are made of aluminum alloy to reduce the weight of the compressor, and the sliding surfaces of the movable scroll member 30 and the fixed scroll member 28, that is, the surface of the spiral body 302 and the side plate 301. whirlpool body 30
30 in the figure for the entire surface where 2 is attached.
As shown in 4, a hard coating treatment such as anodizing treatment (that is, alumite treatment) is performed. In addition, as shown in FIG. 5, the fixed scroll member 28 made of aluminum alloy has a spiral body 282.
A spiral plate 40 made of steel is disposed on the side plate 281 to which it is attached so as to be fitted between the spiral bodies 282, and is fixed to the side plate 281 with screws 41.

In the grooves formed in the axial end surfaces of the spiral bodies 282, 302 of the scroll members 28, 30, soft and wear-resistant tip seals 285, 305 made of plastic such as filled Teflon or polyimide are installed. are arranged respectively.

When the scroll compressor configured as described above is operated, a fixed portion is formed between the side wall of the spiral body 302 of the anodized movable scroll member 30 and the side wall of the spiral body 282 of the fixed scroll member 28 made of aluminum alloy. Between the tip seal 285 disposed on the axial tip surface of the spiral body 282 of the scroll member 28 and the anodized surface of the side plate 301 of the movable scroll member 30, and between the axial tip of the spiral body 302 of the movable scroll member 30. The tip seal 305 disposed on the surface slides between the spiral plate 40 disposed on the side plate 281 surface of the fixed scroll member 28. Then, the side wall of the spiral body 302 and the spiral body 2
82 side wall is sliding between a hard anodized surface and a soft aluminum alloy base, so after there is slight wear in the initial stage of sliding, the fit is extremely good and wear hardly progresses. Also,
Since the tip seal 285 and the surface of the side plate 301 are made of soft, abrasion-resistant plastic and a hard anodized surface, they fit very well and are hardly worn. Similarly, since the tip seal 305 and the spiral plate 40 are made of soft, wear-resistant plastic and the surface of a hard steel plate, they fit very well and are hardly worn. In this way, all sliding movements between the fixed scroll member 28 and the movable scroll member 30 occur between the soft and hard surfaces, so high machining accuracy is not required for the wall heights of both spiral bodies 282 and 302. In both cases, extremely smooth and low-wear sliding can be obtained, and problems such as damage to bearings, clogging of filters in the refrigeration circuit, and reduction in compression efficiency as mentioned above can be avoided. .

Although an embodiment in which the present invention is applied to a scroll compressor having a specific drive mechanism and a rotation prevention mechanism has been described above, it goes without saying that the present invention is not limited to this embodiment.

According to the present invention, a soft sealing element is attached to the axial end face of the spiral body of both the fixed and movable scroll members, and both the scroll members are formed of aluminum or aluminum alloy, and one of the scroll members is made of aluminum or an aluminum alloy. The surface of the spiral body of the scroll member and the surface of the side plate to which the spiral body is attached are treated with a hard coating, and the other scroll member has a spiral-shaped hard wear-resistant plate fitted between the spiral bodies. Therefore, all sliding between both scroll members is performed between the soft and hard surfaces, achieving smooth, low-wear sliding without requiring high machining accuracy for the height of the spiral body wall. be able to. Therefore, it is possible to prevent problems such as damage to bearings and the like due to generation of a large amount of abrasion powder, clogging of filters and the like in the refrigeration circuit, and problems such as reduction in compression efficiency. Furthermore, with the present invention, a hard surface can be created by simply fitting a hard spiral wear-resistant plate into the aluminum base side plate of the other scroll member, and a hard coating is applied only to the side plate surface to create a hard surface. There is no need for the cumbersome and expensive work that occurs when it comes to the surface.

[Brief explanation of the drawing]

FIG. 1 is a central vertical sectional view of a compressor that is an embodiment of the present invention. FIG. 2 is an exploded perspective view of the drive section of the movable scroll member in the embodiment of FIG. 1. FIG. 3 is a sectional view taken along the - line in FIG. 1. 4 is an exploded perspective view showing the structure of the rotation prevention mechanism and thrust bearing of the embodiment shown in FIG. 1. FIG. FIGS. 5a and 5b are front views of the fixed scroll member of FIG. 1 and a spiral steel plate fitted thereto. 10...Compressor housing, 15...Main shaft, 1
54... Drive pin, 28... Fixed scroll member, 285... Chip seal, 30... Movable scroll member, 301... Side plate, 303... Boss,
304...Hard coating, 305...Chipseal,
37... Rotation prevention mechanism, 371... Fixing ring,
372... Sliding ring, 38, 38'... Pocket, 39... Bearing ball, 40... Steel spiral plate, 41... Screw.

Claims (1)

[Scope of utility model registration request] A pair of scroll members each having a spiral body fixed on a side plate are stacked so that both spiral bodies are angularly shifted and mesh with each other, and by the relative circular orbital movement of one scroll member, both spiral members are This is a scroll type compressor that compresses fluid by moving a fluid pocket formed between the bodies to the center and thereby reducing its volume, and the scroll type compressor compresses fluid by moving a fluid pocket formed between the bodies to the center, and thereby reducing the volume thereof. In a scroll type compressor in which a sealing element is attached and both scroll members are made of aluminum or aluminum alloy, the surface of the spiral body of one scroll member and the surface of the side plate to which the spiral body is attached are coated with a hard coating. 1. A scroll type compressor, characterized in that a hard wear-resistant plate is fitted between the spiral bodies of the other scroll member.