JP2003286974A - Scroll fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll fluid machine enabling a heating and a frictional loss to be reduced at sliding parts and enabling a leakage to be reduced by closely fitting a movable scroll to a fixed scroll by a simple back pressure providing means. <P>SOLUTION: The back pressure providing means 10 comprises a mechanism for generating a back pressure by the elastic deformation of a solid such as a rubber and a coiled spring and a structure having gas pressuringly sealed in a space having a skin formed of a bellows. The back pressure providing means 10 having the degree of freedom allowing a follow-up to the swing motion of a movable scroll 1 is installed between the back face of the movable scroll 1 and the bottom face of a housing 4. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a scroll type fluid machine. Specifically, the present invention relates to a scroll type fluid machine represented by a scroll type pump that reduces heat generation and wear loss.

[0002]

2. Description of the Related Art Conventionally, various scroll type fluid machines represented by scroll type pumps have been proposed. The scroll type fluid machine is composed of a movable scroll having a spiral movable scroll blade and a fixed scroll having a fixed scroll blade combined with the movable scroll blade of the movable scroll. The movable scroll blade and the fixed scroll blade have respective blade shapes designed by, for example, an involute curve or an Archimedes spiral. In this configuration, the movable scroll orbits while maintaining a minute gap between the scroll blades of the movable scroll and the fixed scroll, thereby centering the enclosed space formed by the combination of both scrolls from the outside of the spiral portion. It functions to function as a fluid pump by moving it to the side to successively reduce its volume and compress it. For that purpose, it is necessary for the movable scroll to minimize the gap in the axial direction with respect to the fixed scroll. Further, it is necessary to reduce heat generation and friction of the sliding portion (such as the contact portion between the movable scroll and the housing holding the movable scroll) caused by the turning motion.

Conventionally, various scroll type fluid machines have been proposed, but until now, none have sufficiently solved the problems of both. For example, Japanese Patent Publication 1-44
Japanese Patent No. 911 discloses a scroll type fluid machine in which a spring and a piston for pressing a fixed scroll are provided on the back surface of the movable scroll, and the movable scroll is pressed against the fixed scroll until the pressure in the back pressure chamber on the back surface of the movable scroll becomes sufficient. It is disclosed. In this scroll-type fluid machine, the movable scroll is pressed against the fixed scroll by the spring until the back pressure becomes sufficient, so that the wear resistance of the movable scroll can be improved.

However, in the fluid machine concerned,
When starting, the back of the movable scroll and the piston slide,
Excessive power is required at startup. In addition, the piston is constrained in the radial direction and cannot follow along with the orbiting motion, resulting in a sliding mechanism in which the relative displacement between the piston and the movable scroll is large, resulting in large heat generation and friction loss. .

Further, Japanese Unexamined Patent Publication No. 61-223288 discloses a scroll type fluid machine provided with a pressurizing means on the rear surface of a movable scroll for sliding the movable scroll in contact with a fixed scroll. The pressurizing means includes a sliding ring provided on the back surface of the movable scroll, and a spring that presses the sliding ring against the movable scroll.
The movable scroll is sandwiched by a large gap provided between the fixed scroll and the housing that sandwiches the movable scroll. For this reason, a quick rise can be obtained even if the clearance is increased.

However, since the sliding ring is provided, the number of parts is increased and assembly becomes difficult. Further, since the outer periphery of the sliding ring is constrained by the housing, there is a problem in that the sliding ring does not follow along with the turning motion and becomes a sliding portion with a large relative displacement, resulting in large heat generation and friction loss.

Further, in Japanese Patent Publication No. 7-72541, a stationary body for supporting a movable scroll which can orbit and a fixed supporting member which is fixed and supported are provided with flexible supporting means for allowing axial displacement. A scroll type fluid machine is disclosed. Since the stationary body constitutes a part of the housing, it is not a separate member in consideration of slidability, and since it is stationary, it follows the movable scroll along with the turning motion. However, there is a problem that the sliding portion has a large relative displacement, and heat generation and friction loss increase.

On the other hand, JP-A-6-264875 discloses a scroll type fluid machine in which a wear resistant race is rotatably interposed between a movable scroll and a housing for housing a fixed scroll. In this scroll type fluid machine, since the abrasion resistant race rotates, the frictional resistance is reduced.

However, the number of parts is increased in this structure. In addition, the periphery of the wear resistant race is restrained, and the wear resistant race rolls around itself and does not make a turning motion. Therefore, a sliding portion having a large relative displacement with respect to the turning motion is configured, and heat generation and friction loss are large. Further, the wear resistant race is arranged between the movable scroll and the fixed scroll and is not integrated with the back member of the movable scroll.

Japanese Patent Registration No. 2500200 discloses an electric shaver using a spring member that presses a movable blade against a fixed blade. However, the electric razor has one degree of freedom because the movable blade reciprocates, while the movable scroll has two degrees of freedom because it makes a revolving movement. Therefore, the back pressure adding means that can follow a simple movement with one degree of freedom cannot be directly applied as a back pressure adding means that can follow a movement with two degrees of freedom. Further, in the electric razor, the shaving taste is improved by the close contact of the blades, but the back pressure adding means makes the possible scroll blades and the fixed scroll blades in close contact with each other to prevent leakage, and the structure thereof is naturally different. Is.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art. The object of the present invention is to reduce heat generation and friction loss in the sliding portion,
Moreover, it is an object of the present invention to provide a scroll-type fluid machine with less leakage by bringing the movable scroll into close contact with the fixed scroll by means of the back pressure adding means having a simple structure.

[0012]

A scroll type fluid machine of the present invention comprises a movable scroll having spiral scroll blades and a fixed scroll having spiral scroll blades combined with the scroll blades. Circulates around the axis at a certain radius, so that the enclosed space formed by the superposition of both scrolls moves from the outside of the scroll vanes toward the center side to successively reduce the volume and compress the scroll type. In the fluid machine, a back pressure adding means is provided on the back surface of the movable scroll to apply a back pressure to the fixed scroll and to have a degree of freedom capable of following the orbiting motion of the movable scroll.

In this case, the back pressure adding means is
It is preferable to arrange a plurality of them, and it is preferable to arrange the back pressure applying means at equal intervals.

As the back pressure adding means in the present invention, for example, a mechanism for generating back pressure by elastic deformation of a solid such as rubber or spring, especially a coiled spring can be used.

Further, a structure in which a gas is pressurized and enclosed in a space whose outer skin is formed of a bellows can be used as the back pressure applying means.

Further, according to the present invention, the back surface of the movable scroll is provided with a convex portion or a concave portion, and the back pressure adding means is provided.
It is preferable that the back pressure adding means is attached to the convex portion or the concave portion, or the bottom surface of the housing that houses the movable scroll is provided with the convex portion or the concave portion, and the back pressure applying means is attached to the convex portion or the concave portion.

Further, in this case, for example, the back pressure applying means is preferably press-fitted and fastened to the convex portion or the concave portion.

A member which expands and contracts for press-fitting and fastening the back pressure applying means may be provided on the peripheral surface of the convex portion or the concave portion.

Further, it is preferable that the convex portion has a substantially cylindrical shape and is provided with an introduction portion having a larger diameter.

Further, the convex portion may be composed of a pair of cantilever claws which are elastically deformed.

The back pressure applying means may be adhered to the convex portion or the concave portion, screwed and fastened to the convex portion or the concave portion, or fitted and inserted in the convex portion or the concave portion.

Further, it is preferable that the convex portion or the concave portion having the guiding structure of the back pressure applying means is formed, for example, it can be formed in a conical shape, and the fixed side of these convex portions or concave portions having the guiding structure is formed. It is preferable to provide a cylindrical portion having an equal cross section.

Further, the movable scroll and the housing are provided with conical projections for mounting back pressure adding means on the bottom surface of the housing and a coil spring as the back pressure adding means, and the inner diameter of the coil spring is the orbiting radius of the movable scroll. The above is preferable.

These projections can be integrally formed with the movable scroll or the housing by molding, for example.

Further, it is desirable that the back pressure applying means is insert-molded in the movable scroll or is insert-molded in a housing for accommodating the movable scroll.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the drawings. FIG. 1 is an exploded perspective view of a scroll type fluid machine which is an embodiment of the present invention, and FIG. 2 is a sectional structural view of the scroll type fluid machine. The scroll fluid machine includes a movable scroll 1 having a spiral movable scroll blade 1a, a fixed scroll 2 having a fixed scroll blade 2a that is combined with the movable scroll blade 1a of the movable scroll 1, and rotation of the movable scroll 1 is prevented. Oldham ring 3, a housing 4 that holds the Oldham ring 3 and houses the orbiting scroll 1, and a motor 5 and a motor 5 that drive the orbiting scroll 1.
The eccentric shaft 6 for converting the driving force of the above into the orbital motion of the movable scroll 1 is provided. The Oldham ring 3 is provided with a claw 3a for preventing rotation of the movable scroll 1, the movable scroll 1 has a movable scroll blade 1a and an end plate 1b supporting the blade 1a, and the back surface of the end plate 1b is A recess 1c that fits with the claw 3a is provided. Further, a convex portion 3b for restricting the revolving movement of the movable scroll 1 is provided on the lower surface of the Oldham ring 3. This convex part 3
"b" is fitted in the revolution control groove 4b provided in the housing 4 to form a scroll type fluid machine. Eccentric shaft 6
The eccentric cam 7 provided at the tip of the orbit causes the movable scroll 1 to revolve, thereby exerting a fluid mechanical function. In addition, 7a is a protrusion 1d provided on the lower surface of the movable scroll 1.
Holes 4a into which the eccentric cams 7 provided in the housing 4 are inserted. Reference numeral 8 is a spring that suppresses axial deviation of the movable scroll 1.

In this scroll type fluid machine, back pressure is applied to the fixed scroll 2 between the lower surface of the end plate 1b of the movable scroll 1 and the bottom surface of the housing 4 to follow the orbiting motion of the movable scroll 1. The back pressure adding means 10 having possible degrees of freedom is provided. The back pressure adding means 10 only needs to be able to follow the orbiting motion of the orbiting scroll 1, and the back pressure adding means 10 may be one.
As shown in FIG. 3, a plurality of back pressure adding means 10 may be used.
Further, as a followable structure, a structure in which the back pressure adding means 10 is integrated with the movable scroll 1 so as to move together with the movable scroll 1 in the housing 4, and a structure in which the back pressure adding means 10 is integrated with the housing 4 and is movable above the back pressure adding means 10. 1, a structure in which the orbiting motion is performed, a movable scroll 1 and a housing 4
Any of a structure in which the movable scroll 1 is fixed to both of the movable scroll 1 and the movable scroll 1 can be rotated by twisting the back pressure adding means 10 or the like, and the movable scroll 1 can be rotated without being fixed to the movable scroll 1 and the housing 4. . By providing such a back pressure adding means 10, the movable scroll 1 is pressed against the fixed scroll 2 side, and the sliding portion between the end plate 1b of the movable scroll 1 and the bottom surface of the housing 4 is greatly reduced. For this reason, friction and heat generation in the sliding portion are greatly reduced.

Further, the back pressure adding means 10 uniformly presses the movable scroll 1 against the fixed scroll 2 so that there is little variation due to the disposition portion, and the larger the number, the closer to the distributed load. Therefore, it is preferable to use a plurality of back pressure adding means 10, and the arrangement thereof is preferably evenly arranged on the rear surface of the end plate 1b of the movable scroll 1 as shown in FIG. In order to arrange them evenly, for example, as shown in FIG. 4, the circumferential angles formed by the adjacent back pressure applying means 10 can be made uniform. At this time, it is preferable to arrange the back pressure applying means 10 in the widest area on the back surface of the end plate 1b as far as possible. This suppresses fluctuations and variations in the downward direction of the movable scroll 1 (housing 4 direction) due to the momentum and gas compression force associated with the orbiting movement of the movable scroll 1.
The movable scroll 1 can be stably supported. Furthermore, by disposing a plurality of back pressure applying means 10, the load applied to the orbiting scroll 1 itself changes from concentrated load to distributed load, and local stress concentration is relieved, so deformation of the end plate 1b is also suppressed. In particular, when the back pressure adding means 10 is made of a resin material, its Young's modulus is small, and it is important to make a distributed load by a plurality of arrangements.

The back pressure adding means 10 is not particularly limited as long as it can achieve the above-mentioned object. For example, an elastic body structure made of rubber, a metal spring, a resin material or the like and a skin are made of bellows. For example, a structure in which a gas is pressurized and enclosed in the space is used. Back pressure adding means 1 shown in FIG.
0 is made of rubber which is an elastic body. Rubber is
The plurality of back pressure applying means 10 are processed into a cylindrical shape and have the same size. Further, the back pressure adding means 10 shown in FIG. 6 is composed of a metal spring that is an elastic body, more specifically, a coil spring. As described above, as the back pressure adding means 10, one that can generate back pressure by elastic deformation of the solid is preferably used. That is, when the fluid machine is assembled, the compression force is applied between the movable scroll 1 and the housing 4 to exert a restoring force, which causes a back pressure on the fixed scroll 2. Back pressure is
It is generated with the displacement of the solid, and if the elastic coefficient of the solid to be formed is clear in advance, it can be obtained because the relation between the displacement and the back pressure is proportional. As a result,
A design for generating back pressure can be easily performed, and a stable back pressure can be obtained because the elastic coefficient is a solid eigenvalue. In particular, when the former rubber is used, the vibration and noise generated by the orbiting motion of the movable scroll 1 can be suppressed and attenuated. Furthermore, in order to obtain the same back pressure, the weight can be reduced as compared with the means using a metal material. On the other hand, when the latter spring, for example, a coiled spring is used, the elastic coefficient is clearer and more specific than that of rubber, and the relationship between displacement and back pressure is linear, which makes designing very easy. . In particular, in the coiled spring, it is possible to increase the displacement with respect to the generated force (decrease the elastic coefficient). That is, if the tolerances of the parts configured to generate the back pressure are equal, the larger the deflection amount of the spring, the smaller the back pressure variation ratio, and the more stable back pressure can be obtained. Further, the coiled spring can be moved not only in the axial direction but also in the radial direction, so that the coiled spring can easily follow the orbiting movement of the movable scroll 1 as compared with a flat contact like rubber. Therefore, the friction in the sliding portion is further reduced.

The back pressure adding means 10 shown in FIG. 7 is composed of a bellows structure. This bellows structure has a space whose outer skin is formed by a bellows, and a gas such as air or nitrogen is pressurized and sealed inside the space. That is, the back pressure is determined by the combination of the rigidity of the bellows and the gas pressure, and there is a correlation that the back pressure is increased by increasing the gas filling pressure. At the time of assembly, a bellows is attached in a no-load state without encapsulating gas, and the gas is enclosed in the bellows under pressure and the interior expands, thereby expanding in the axial direction and applying back pressure to the movable scroll 1 integrated with the bellows. generate.

According to this bellows structure, since the movable scroll 1 is floated by the gas pressure inside and supported by the back pressure, it is possible to damp vibrations and noise accompanying the orbiting motion. Further, as compared with the above elastic body structure, the fluctuation of the back pressure due to the fluctuation of the turning motion in the axial direction can be alleviated, and stable support can be easily obtained. Further, depending on the material, the bellows can move not only in the axial direction but also in the radial direction, so that it is easy to follow the orbiting motion of the movable scroll 1, and the friction at the sliding portion is easily reduced.

The back pressure applying means 10 need only have the degree of freedom to follow the orbiting motion of the movable scroll 1, and the back surface of the end plate 1b of the movable scroll 1 (the back surface of the movable scroll 1) and the bottom surface of the housing 4. However, it is preferable that they are evenly arranged as described above.

In order to dispose the back pressure applying means 10 at a predetermined position, the movable scroll 1 shown in FIG. 8 has a convex portion 11 on the back surface for mounting the back pressure applying means 10. For example, when the coil spring is used, the convex portion 11 is inserted within the diameter of the coil spring. At this time, the convex portion 11 is formed in a substantially columnar shape. For example, as shown in FIG. 9, the convex portion 11 can be integrally formed with a pair of molds 9 to integrally form the convex portion 11 with the movable scroll 1. . Alternatively, after molding only the movable scroll 1, the columnar convex portions 10 can be integrated by welding, adhesion, or the like. By providing such a convex portion 11, the back pressure adding means 10 can be arranged at a desired position, and the positioning accuracy is improved.

At this time, for example, the back pressure applying means 10 shown in FIG. 10 is so-called interference fit, that is, the outer diameter of the convex portion 11 is larger than the inner diameter of the back pressure applying means 10.
It is press-fitted and fastened to the convex portion 11. Thereby, the back pressure adding means 10 can be completely integrated, and the back pressure applying means 10 can be prevented from coming off.

Further, the convex portion 11 shown in FIG. 11 is provided with a member 12 for expanding and contracting around which the back pressure applying means 10 is press fitted and fastened. The member 12 includes vulcanized rubber,
Those having rubber elasticity such as elastomer and silicone rubber are preferably used. This member 12 has, for example, an outer diameter of the convex portion 11 and an inner diameter of the member 12 that expands and contracts to be substantially equal, and the member 12 that expands and contracts with respect to the convex portion 11 is press-fitted into a mold having a movable scroll shape. A shape that can be press-fitted into the inner diameter of the back pressure applying means 10 by using a thermoplastic elastomer as the member 12 that expands and contracts after obtaining a movable scroll molded body in which a resin 11 is injection-molded to obtain an integrated convex portion 11. It is possible to adopt a method in which the member 12 is integrated by injection molding into another mold. In this way, by interposing the member 12 that expands and contracts, the member 12 is deformed when press-fitting, so that the stress at the time of press-fitting is relieved and damage to each member can be prevented. Further, it is possible to relieve the stress acting between the back pressure applying means 10 and the convex portion 11 during operation.

The convex portion 11 shown in FIG. 12 is formed in a substantially cylindrical shape, and is provided with an introduction portion 13 having a larger diameter on the insertion side of the back pressure applying means 11. After forming the orbiting scroll 1, the convex portion 11 is bonded to the separately manufactured convex portion 11,
It is fixed by methods such as press fitting and screwing. In such a convex portion 11, once the back pressure adding means 10 is press-fitted and fastened, the introduction portion 13 serves as a pull-out prevention mechanism, which makes it difficult to pull out, and the pull-out during operation is reliably prevented.

The convex portion 11 shown in FIG. 13 is composed of a pair of cantilever claws 11a that elastically deform. Each cantilever claw 1
1a has a shape in which the tip thereof is pointed outward, and the cantilever claw 11a elastically deforms in the radial direction. Since this convex portion 11 is cantilevered, it is easily deformed, damage to parts is prevented, and the back pressure applying means 10 is easily inserted.
Further, after the press-fitting and fastening, the restoring force of the cantilever claw 11a enhances the coupling force with the back pressure applying means 10. Further, the tip portion prevents the back pressure applying means 10 from coming off.
In this case, when the back pressure applying means 10 is press-fitted and fastened, stress is concentrated on the connecting portions of the cantilevered claws 11a, 11a and the movable scroll 1, and there is a strong possibility of damage, so as shown in FIG. It is better to provide the R part in the. This prevents damage due to stress concentration.

Further, in the example shown in FIG. 14, the back pressure applying means 10 is adhesively fixed to the convex portion 11. By fixing with the adhesive 14 in this way, integration becomes easy. Also, since there is no backlash, vibration noise is reduced. Moreover, since the sliding between the convex portion 11 and the back pressure applying means 10 is eliminated, the damage to the parts is reduced.

The convex portion 11 shown in FIG. 15 has a male screw shape, and the back pressure applying means 10 is screwed to the convex portion 11. The back pressure applying means 10 can be integrated with the movable scroll 1 by screwing in this manner. In this case, the screw of the convex portion 11 is processed so as to be screwed with the coil spring. (Adjusting to the wire pitch and inner diameter of the coiled spring.) By thus screw-fastening, the back pressure adding means 10 can be easily assembled.

The back pressure applying means 10 shown in FIG. 16 is a so-called clearance fit, that is, the outer diameter of the convex portion 11 is smaller than the inner diameter of the back pressure applying means 10 and is fitted and inserted into the convex portion 11. Has been done. By this, by inserting and fitting, the protrusion 11 and the back pressure applying means 10 can be easily assembled without applying pressure.

The convex portion 11 shown in FIG. 17 is the back pressure applying means 1
It has a structure of 0 attraction. The convex portion 11 has a smaller diameter on the insertion side of the back pressure applying means 10, a side surface of the convex portion 11 is formed with a taper, and the insertion die and the fixed side have different cross-sectional areas. For example, as shown in FIG. 18, it may have a substantially truncated cone shape. In this case, when a coil spring is used as the back pressure adding means 10 as shown in FIG. 17, the inner diameter portion of the coil spring is guided to the convex portion 11. As a result, the fastener can be fastened without deviating from the target position and the assembly becomes easy.

In this case, as shown in FIG. 19, it is preferable to provide a cylindrical portion 15 having the same sectional area on the fixed side of the convex portion 11, that is, on the base end portion on the convex portion 11 side. The cylindrical portion 15 has a diameter substantially equal to the inner diameter of the back pressure adding means 10, that is, in the case of a coil spring, the inner diameter of the coil spring. As a result, as shown in (b) of the figure, the fastening with the back pressure applying means 10 is strengthened on the fixed side of the convex portion 11, and the back pressure applying means 10 is prevented from coming off and rattling.

In each of these embodiments, the back pressure applying means 10 is positioned by using the convex portion 11, but as the positioning means, a concave portion 21 is formed on the rear surface of the end plate 1b of the movable scroll 1 as shown in FIG. You may decide to form,
The back pressure applying means 10 can be mounted in the recess 21.
The recess 21 shown in FIG. 20 has different cross-sectional areas on the insertion side and the fixed side, and the inner surface of the recess 21 is tapered. Therefore, for example, the outer diameter portion of the coiled spring is guided into the recess 21 and is fastened without shifting from the target position. Further, as shown in FIG. 21, a cylindrical portion 22 having a uniform cross-sectional area on the fixed side may be provided.

Of course, even when the recess 21 is formed,
Various modifications are conceivable as in the case where the convex portion 11 is provided. For example, although not shown, in order to press-fit and fasten the back pressure applying means 10 into the recess 21, the inner diameter of the recess 21 may be made smaller than the outer diameter of the back pressure applying means 10 to form a so-called interference fit. Further, the inner diameter of the recess 21 may be made larger than the outer diameter of the back pressure applying means 10 so that the recess 21 is fitted and inserted as a so-called clearance fit. Further, a member 12 that expands and contracts for press-fitting and fastening the back pressure applying means 10 may be provided on the inner peripheral surface of the recess 21, or a female screw may be cut so as to be screwed onto the inner surface of the recess 21.

Further, the convex portion 1 on which the back pressure applying means 10 is mounted
The recess 1 or the recess 21 may be provided on the bottom surface of the housing 4. In FIG. 22, the convex portion 11 is provided on the bottom surface of the housing 4. This convex portion 11 is also used for the back pressure applying means 10.
The same modification as the convex portion 11 on the movable scroll 1 side can be considered.

FIG. 23 is a diagram showing a case where the convex portions 11 for mounting the back pressure adding means 10 are provided on both the back surface of the movable scroll 1 and the bottom surface of the housing 4. The movable scroll 1 and the two convex portions 11 on the housing 4 are each formed in a conical shape having the same size, and a coil spring is used for the back pressure applying means 10. As shown in FIG. 1, in the scroll-type fluid machine, in order to orbit the movable scroll 1, from the center of the eccentric shaft of the motor 5 to the center of the protrusion 1d on the back surface of the movable scroll 1, the orbiting radius (=
It is offset by r). Therefore, if the convex portions 11 are arranged on the bottom surface of the housing 4 similarly to the arrangement of the convex portions 11 of the movable scroll 1, the positions of the both convex portions 11 are displaced by the orbiting radius when the fluid machine is assembled. For this reason, it becomes very difficult to mount the back pressure adding means 10 between the both convex portions 11. Therefore, in the example shown in FIG. 23, the inner diameter of the coiled spring is set to be equal to or larger than the turning radius. Thus, when the coiled spring is mounted on the convex portion 11 on the housing 4 side during assembly of the fluid machine, the tip of the convex portion 11 on the movable scroll 1 side is located within the inner diameter of the coiled spring. Become. Further, since the convex portion 11 is formed in a conical shape, the coiled spring can be easily attached to the convex portion 11 on the movable scroll 1 side by the so-called guiding effect. In the drawing, the convex portion 11 is drawn in a truncated cone shape, but it does not have to be a strict conical shape in practice, and may be a truncated cone shape in which the tip of the convex portion 11 is cut out as shown in the drawing. If the inner diameter is equal to or larger than the turning radius, the tip end of the convex portion 11 is located substantially within the inner diameter of the coil spring, which facilitates mounting of the coil spring.

Further, the base end of the convex portion 11 is preferably formed to have a diameter substantially equal to the inner diameter of the coil spring, and more preferably,
As shown in FIG. 19, it is preferable to provide a cylindrical portion 15 having an equal cross section. As a result, the coiled spring is
It is press-fitted and fastened to eliminate rattling during driving,
Vibration and noise can be reduced.

Besides this, the back pressure adding means 10 can be integrated with the movable scroll 1 and the housing 4 by various methods. For example, the movable scroll 1 shown in FIG.
The back pressure adding means 10 is integrated by insert molding. Further, in the housing 4 shown in FIG. 25, the back pressure adding means 10 is integrated by insert molding.
Thus, by insert molding, the back pressure applying means 10 can be integrated reliably and easily, and the scroll fluid machine can be easily assembled.

Further, in the mounting of the back pressure adding means 10 described above, the coiled spring has been described as an example, but it is also applicable to the case where an elastic body such as rubber is used. For example, when cylindrical rubber is used, although not shown, a concave portion 21 into which the convex portion 11 is fitted is formed from the end surface thereof, and the convex portion 11 of the movable scroll 1 and the concave portion 21 are formed.
The structure should be fitted. As a result, as described above, press-fitting and adhesive fastening can be performed. Further, when the convex portion 11 having a male screw is used, the concave portion 21 is screwed into the convex portion 11 so that the inside of the concave portion 21 becomes a female screw and can be easily screwed. It can also be attached by adhesion or the like.

Thus, the back pressure adding means 10 capable of following the orbiting motion of the movable scroll 1 is made of rubber or a coiled spring on the back surface of the movable scroll 1 so that the movable scroll 1 and the housing 4 (sliding) can be moved. It is possible to reduce heat generation and friction loss in the moving part).

[0051]

The scroll type fluid machine of the present invention is provided with a back pressure adding means for giving a back pressure to the fixed scroll on the back surface of the movable scroll and having a degree of freedom capable of following the orbiting motion of the movable scroll. Therefore, it is possible to improve the adhesion between the movable scroll and the fixed scroll to provide a fluid machine with less leakage and a fluid mechanism with less frictional resistance and less heat generation in the sliding portion existing on the back surface of the movable scroll.

By providing a plurality of back pressure adding means in the scroll type fluid machine, the back pressure can be dispersed over a wide range with respect to the movable scroll, and the movable scroll can be stably supported. Further, by evenly arranging the back pressure adding means, the back pressure applying means can be supported more stably.

By providing a mechanism for generating a back pressure by elastic deformation of a solid as the back pressure adding means, the back pressure can be easily designed, and the elastic coefficient has a unique value, so that a stable back pressure can be obtained. You can

For example, if it is made of rubber, it is possible to enhance the noise and vibration damping effect during driving and to reduce the weight. Further, if it is composed of a spring, a more stable back pressure than that of rubber can be obtained, and the design is easy. In particular, if a coiled spring is used, it can be moved in the lateral direction and the followability can be improved. Further, since the displacement can be increased, it is possible to suppress variations in back pressure. Further, if the outer skin is formed of a structure in which a gas is pressurized and enclosed in the space formed of a bellows, the structure can be moved in the lateral direction and the followability can be improved. Further, since the gas pressure is used, the fluctuation of the back pressure due to the fluctuation of the movable scroll is small.

Further, by providing a convex portion or a concave portion on the back surface of the movable scroll or the bottom surface of the housing for accommodating the movable scroll and mounting the back pressure applying means on the convex portion or the concave portion, the assemblability is improved, The positioning accuracy of the pressure applying means is improved.

In this case, the back pressure adding means is
By press-fitting and fastening into the convex portion or the concave portion, it is completely integrated with the movable scroll and prevented from coming off during driving.

Further, by providing a member that expands and contracts for press-fitting and fastening the back pressure applying means on the peripheral surface of the convex portion or the concave portion, damage to the parts can be prevented.

Further, by forming the convex portion into a substantially cylindrical shape and providing the introduction portion having a larger diameter, it is possible to prevent the back pressure applying means from coming off after the press-fitting.

Also, by forming the convex portion with a pair of elastically deformable cantilever claws, it is possible to prevent disengagement after press fitting, facilitate press fitting, and reduce damage to parts.

Further, if the back pressure applying means is adhered to the convex portion or the concave portion, the back pressure applying means can be integrated by a very simple method, and the back pressure applying means and the convex portion or the concave portion will not be detached from each other. Noise and vibration are reduced.

Furthermore, by assembling the back pressure applying means into the convex portion or the concave portion by screwing, fitting or inserting, the assembling becomes easy.

If the convex portion or the concave portion is provided with the structure for guiding the back pressure adding means, not only the back pressure adding means can be easily mounted but also the positional deviation at the time of assembly can be corrected. The time yield can be improved. For example, if it is made into a conical shape, the back pressure applying means can be more surely introduced. In this case, if the convex portion or the concave portion is provided with a cylindrical portion having the same cross-sectional area on the fixed side, the mounting of the back pressure adding means can be ensured.

Further, a conical convex portion for mounting back pressure adding means on the bottom surface of the movable scroll and the housing, and a coil spring as the back pressure adding means are provided, and the inner diameter of the coil spring is the orbiting radius of the movable scroll. With the above, the coil spring can be attached to the convex portion without bending and the assembling can be facilitated.

If the convex portion is integrally molded with the movable scroll or the housing by molding, the number of constituent parts can be reduced.

If the back pressure adding means is insert-molded on the movable scroll or the housing, the work of mounting the back pressure adding means can be omitted and the assembling can be facilitated.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a scroll type fluid machine according to an embodiment of the present invention.

FIG. 2 is a cross-sectional structural diagram of the scroll type fluid machine shown in FIG.

FIG. 3 is a perspective view showing a state in which a plurality of back pressure adding means are provided.

FIG. 4 is a diagram showing an arrangement example of a plurality of back pressure adding means.

FIG. 5 is a cross-sectional view showing a movable scroll using rubber as a back pressure adding means.

FIG. 6 is a cross-sectional view showing a movable scroll using a coil spring as a back pressure adding means.

FIG. 7 is a cross-sectional view showing a movable scroll using a bellows structure as a back pressure adding means.

FIG. 8 is a cross-sectional view showing a movable scroll provided with a convex portion on which a back pressure adding means is mounted.

FIG. 9 is an explanatory diagram showing a method of forming a convex portion.

FIG. 10 is an example showing the integration of the convex portion and the back pressure adding means.

FIG. 11 is a diagram showing another configuration of the convex portion.

FIG. 12 is a diagram showing still another configuration of the convex portion.

FIG. 13A is a diagram showing still another configuration of the convex portion,
(B) is the enlarged view.

FIG. 14 is another example showing the integration of the convex portion and the back pressure adding means.

FIG. 15 is another example showing the integration of the convex portion and the back pressure adding means.

FIG. 16 is another example showing the integration of the convex portion and the back pressure adding means.

FIG. 17 is a diagram showing still another configuration of the convex portion.

FIG. 18 is a diagram showing still another configuration of the convex portion.

FIG. 19 (a) is an enlarged view showing still another configuration of the convex portion, and FIG. 19 (b) is an enlarged view showing a state in which back pressure applying means is attached to the convex portion.

FIG. 20 is a cross-sectional view showing a movable scroll provided with a recess for mounting back pressure adding means.

FIG. 21 is an enlarged view showing another configuration of the recess.

FIG. 22 is a cross-sectional view showing a part of a housing having a convex portion for mounting a back pressure adding means.

FIG. 23 is a view showing an example in which a convex portion for mounting back pressure adding means is provided on the movable scroll and the bottom surface of the housing.

FIG. 24 is a cross-sectional view showing a movable scroll in which back pressure adding means is insert-molded.

FIG. 25 is a cross-sectional view showing a part of the housing in which the back pressure applying means is insert-molded.

[Explanation of symbols]

1 Movable scroll 1a Movable scroll scroll blades 4 housing 10 Back pressure loading means 11 Convex part for mounting back pressure load means 21 Recess for mounting back pressure load means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Naoyuki Kondo             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Koichi Hirai             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Kazunobu Nakata             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Takeshi Yano             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F term (reference) 3H029 AA02 AA14 AB01 AB03 BB16                       BB43 CC05 CC19                 3H039 AA03 AA06 AA12 BB01 BB02                       BB04 BB28 CC02 CC21 CC24                       CC25

Claims (24)

[Claims] 1. A movable scroll having spiral scroll blades, and a fixed scroll having spiral scroll blades combined with the scroll blades, wherein the movable scroll orbits at a constant radius around an axis. As a result, in a scroll type fluid machine in which a hermetically closed space formed by superposition of both scrolls moves from the outside of the scroll blade toward the center side to successively reduce the volume and compresses the fixed scroll on the back surface of the movable scroll. A scroll-type fluid machine comprising: a back pressure applying unit that applies a back pressure and has a degree of freedom capable of following the orbiting motion of the movable scroll. 2. A scroll type fluid machine according to claim 1, wherein a plurality of the back pressure applying means are arranged. 3. The scroll type fluid machine according to claim 2, wherein the back pressure applying means are arranged at equal intervals. 4. The scroll type fluid machine according to claim 1, wherein the back pressure adding means is a mechanism for generating back pressure by elastic deformation of a solid. 5. The scroll type fluid machine according to claim 4, wherein the back pressure applying means is rubber. 6. The scroll type fluid machine according to claim 4, wherein the back pressure applying means is a spring. 7. The scroll type fluid machine according to claim 5, wherein the spring is a coil spring. 8. The scroll-type fluid machine according to claim 1, wherein the back pressure applying means is a structure in which a gas is pressurized and enclosed in a space whose outer skin is formed of a bellows. 9. The scroll type fluid machine according to claim 1, wherein a convex portion or a concave portion is provided on the back surface of the movable scroll, and the back pressure applying means is mounted on the convex portion or the concave portion. 10. The back pressure applying means includes a convex portion or a concave portion on a bottom surface of a housing for accommodating the movable scroll,
The scroll type fluid machine according to claim 1, wherein the scroll type fluid machine is mounted on the convex portion or the concave portion. 11. The scroll type fluid machine according to claim 9, wherein the back pressure applying means is press-fitted and fastened to the convex portion or the concave portion. 12. The member according to claim 9, wherein a member that expands and contracts for press-fitting and fastening the back pressure applying means is provided on a peripheral surface of the convex portion or the concave portion. Scroll type fluid machine. 13. The scroll type fluid machine according to claim 9, wherein the convex portion has a substantially cylindrical shape and is provided with an introduction portion having a larger diameter. 14. The scroll type fluid machine according to claim 9, wherein the convex portion comprises a pair of cantilever claws that elastically deform. 15. The back pressure applying means is adhered to the convex portion or the concave portion.
A scroll type fluid machine according to any one of 1. 16. The scroll type fluid machine according to claim 9, wherein the back pressure applying means is screwed and fastened to the convex portion or the concave portion. 17. The scroll type fluid machine according to claim 9, wherein the back pressure applying means is fitted and inserted into the convex portion or the concave portion. 18. The scroll type fluid machine according to claim 9, wherein the convex portion or the concave portion has a structure for guiding the back pressure applying means. 19. The scroll type fluid machine according to claim 18, wherein the convex portion or the concave portion has a conical shape. 20. The scroll type fluid machine according to claim 18, wherein a cylindrical portion having the same cross-sectional area is provided on the fixed side of the convex portion or the concave portion. 21. A conical convex portion for mounting back pressure adding means on the bottom surface of the movable scroll and the housing, and a coil spring as the back pressure adding means, and the inner diameter of the coil spring is the orbiting radius of the movable scroll. It is above, The scroll type fluid machine of Claim 1 characterized by the above-mentioned. 22. The scroll type fluid machine according to claim 9, wherein the convex portion is integrally formed with the movable scroll or the housing by molding. 23. The back pressure applying means is insert-molded to the movable scroll.
The scroll-type fluid machine described. 24. The scroll type fluid machine according to claim 1, wherein the back pressure adding means is insert-molded in a housing that houses the movable scroll.