JP2000176722A - Machining method of revolving scroll and scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machining method of revolving scroll and a scroll compressor which can reduce the gap between the tooth of a revolving scroll and the tooth of a fixed scroll by improving the plane level of the end plate and the tooth crest in the revolving scroll, and scroll outline accuracy of the tooth side surface, and improves the performance as the scroll compressor by improving the seal property of a compression room. SOLUTION: In this machining method of a revolving scroll, the outer peripheral surface is fixed by making a machining standard surface provided to the rear side of an end plate 1a in a revolving scroll 1 for being machined as the standard, and furthermore, a cutting tool 2 is rotated in the condition supporting the center part of the end plate 1a of the revolving scroll for machining by the moving body of a dash pot 5, so as to cutting machine at least the scroll side surface of the revolving scroll for machining.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor used for an air conditioner or the like, and more particularly, to a method for machining a revolving scroll which forms a pump in combination with a fixed scroll.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open Publication No.
No. 712 (prior art). This prior art includes an orbiting scroll 1 as shown in FIG.
Using the circumferential groove provided on the outer periphery of the end plate portion 1a and the radial groove formed in the chuck portion, the pulling claw 3 on the backing plate 4 side is used.
Is inserted into the groove, and the pulling claw 3 is pressurized in a direction parallel to the axis of the orbiting scroll 1 in a state in which the orbiting scroll 1 is evenly straddled across the radial groove. It is described that processing is performed by an end mill or the like in a state in which the parts are not closely adhered and fixed with high precision. According to this conventional processing method, the end surface of the orbiting scroll is vertically brought into contact with the backing plate surface which is easy to obtain the right-angle accuracy, and can be fastened and fixed with a small elastic deformation of the pulling claw and the work. The flatness of the mirror surface can be obtained.

[0003]

However, in the above-mentioned conventional machining method, since the central portion of the orbiting scroll is not fixed, the orbiting scroll is liable to be elastically deformed by the cutting force acting on the orbiting scroll during machining, and the end surface of the mirror plate and the teeth are not fixed. There were problems such as the inability to obtain the flatness of the front surface and the vortex contour accuracy of the tooth side surface. For example, as shown in FIG.
When end milling e, a large cutting force acts on the orbiting scroll 1 in the axial direction, so that the orbiting scroll 1 sinks largely in the axial direction at the center. At this time, if the elastic deformation of δ occurs during the cutting of the central portion, δ will be left uncut, and the height of the tooth tip after processing will increase by δ at the central portion, and the flatness of the tooth tip surface will deteriorate. Further, as shown in FIG. 13, also in the processing of the tooth side surface, an elastic deformation occurs due to the cutting force acting on the tooth. As a result, the vortex contour accuracy also deteriorates.

In the conventional machining method, since the central portion of the orbiting scroll is not fixed, if the machining conditions such as the number of revolutions of the end mill are increased, chatter vibration is likely to occur, and desired machining accuracy can be obtained. However, there was a problem that the processing efficiency could not be improved.

[0005] An object of the present invention is to solve the above problems.
By improving the flatness of the end plate surface and the tip surface of the orbiting scroll, and the vortex contour accuracy of the tooth side surface, it is possible to reduce the gap between the teeth of the orbiting scroll and the teeth of the fixed scroll, thereby improving the sealing performance of the compression chamber. Accordingly, it is an object of the present invention to provide a orbiting scroll machining method and a scroll compressor which improve the performance as a scroll compressor. Another object of the present invention is to improve the machining efficiency by increasing the machining conditions such as the number of revolutions of the cutting tool so as to suppress the occurrence of chatter vibration and obtain a desired machining accuracy, thereby improving machining efficiency. It is an object of the present invention to provide a method for processing a revolving scroll.
Another object of the present invention is to provide a method of manufacturing a scroll compressor capable of realizing an inexpensive and high-performance scroll compressor with improved processing accuracy and processing efficiency.

[0006]

In order to achieve the above object, the present invention provides an orbiting scroll to be machined, wherein an outer peripheral portion is fixed with reference to a machining reference surface provided on the back surface of the mirror plate surface. By rotating a cutting tool (including a polishing tool) in a state where the center of the end plate of the orbiting scroll to be processed is supported by the moving body of the dash pot, at least the vortex side surface of the orbiting scroll to be processed This is a method for machining a revolving scroll, which is characterized by cutting a circle. Further, the present invention provides an orbiting scroll for processing, wherein an outer peripheral portion is fixed with reference to a processing reference surface provided on a back surface of the end plate surface of the orbiting scroll for processing, and further, a center portion of the end plate of the orbiting scroll for processing is viscous. Cutting tools (including polishing tools) supported by the moving part of a mechanism having characteristics
And turning at least the vortex side surface of the to-be-processed orbiting scroll.

Further, the present invention is characterized in that the orbiting scroll to be machined is fixed with reference to a machining reference plane provided on the back surface of the mirror plate surface, and the center of the end plate of the orbiting scroll to be machined is By rotating a cutting tool (including a polishing tool) in a state of being supported by a moving body of a buffer mechanism having a damping coefficient equal to or more than a critical damping coefficient of the orbiting scroll for processing, at least the orbiting scroll for processing is formed. A machining method of the orbiting scroll, characterized in that a side surface of the spiral is cut. Further, according to the present invention, the outer peripheral portion is fixed with reference to a processing reference surface provided on the back surface of the mirror plate surface in the orbiting scroll for processing, and further, the center portion of the end plate of the orbiting scroll for processing is fixed. A turning scroll machining method characterized by cutting at least the vortex side surface of the orbiting scroll to be processed by rotating a cutting tool (including a polishing tool) in a state.

Further, the present invention is characterized in that, in the above-mentioned method for machining a revolving scroll, the swirl bottom surface of the revolving scroll to be processed is further cut. Further, the present invention is characterized in that, in the method of machining the orbiting scroll, a tooth tip surface of the orbiting scroll to be processed is further cut. Further, the present invention is characterized in that, in the orbiting scroll machining method, the center of the end plate of the orbiting scroll to be processed is connected to the moving body by a magnet. Further, the present invention is characterized in that, in the orbiting scroll machining method, the connection between the center of the end plate of the orbiting scroll to be processed and the movable body is controlled by an electromagnet which can be controlled.

Further, the present invention is a scroll compressor characterized in that a compression chamber is constituted by a revolving scroll machined by the method for machining a revolving scroll and a fixed scroll. Further, the present invention provides a flatness of the tooth tip surface of 5
A scroll compressor characterized in that a compression chamber is constituted by an orbiting scroll having a diameter of about μm or less and a fixed scroll.

As described above, according to the above configuration,
By improving at least the flatness of the end plate surface and the tooth tip surface of the orbiting scroll, and the accuracy of the vortex contour on the tooth side, even if the gap between the teeth of the orbiting scroll and the teeth of the fixed scroll is reduced, the teeth come into contact with each other. As a result, it is possible to realize a scroll compressor having improved compression performance by improving the sealing performance of the compression chamber formed by the orbiting scroll and the fixed scroll. Further, according to the above configuration, at least the flatness of the end plate surface and the tip surface of the orbiting scroll and the accuracy of the vortex contour on the tooth side surface are improved, so that the gap between the teeth of the orbiting scroll and the teeth of the fixed scroll is reduced. The scroll compressor can prevent the contact between teeth, and as a result, improve the sealing performance of the compression chamber composed of the orbiting scroll and the fixed scroll, improve the compression performance, and reduce the power consumption. Can be realized. Further, according to the above configuration, even if the number of revolutions of the end mill is increased, machining can be performed without generating chatter vibration, the machining time can be reduced, and the flatness of the tooth tip surface is 4 μm, which is about 5 μm or less. It became possible to improve.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method for processing an orbiting scroll and a scroll compressor according to the present invention will be described with reference to the drawings. The scroll compressor is composed of an orbiting scroll 1 and a fixed scroll 10, as shown in FIG. 11 is a compression chamber, and 12 is a discharge hole.
Then, the scroll compressor is repeatedly changed from the state shown in FIG. 9A to the state shown in FIG. 9B, the state shown in FIG. 9C, and the state shown in FIG. The intruding medium is sequentially compressed by the compression chamber 11 and the discharge hole 1
2 will be exhaled. Orbiting scroll 1
Normally, a tooth 1c composed of an involute curve is formed on the surface of the mirror plate 1a, and a bearing boss 1b for rotating the orbiting scroll, a keyway 1d, and the like are formed on the back surface thereof.

FIG. 1 is a view for explaining one embodiment of a method for machining a revolving scroll according to the present invention. As shown in FIG. 1, the outer peripheral portion of the orbiting scroll 1 is axially fixed by the pulling claw 3 so that the back surface of the end plate is pressed against the backing plate 4. In particular, the outer peripheral portion of the orbiting scroll 1 may be tightly fixed to the backing plate 4 in the same manner as described in JP-A-6-712. That is, by utilizing a circumferential groove 1f provided on the outer periphery of the end plate portion 1a of the orbiting scroll 1 and a radial groove (not shown) formed in the chuck portion, the tip of the pulling claw 3 on the backing plate 4 side is connected to the circumferential groove 1f. , And press the pulling claw 3 in the direction parallel to the axis of the orbiting scroll 1 in a state where the orbiting scroll 1 is evenly stretched across the radial groove. I do. Further, regarding the central portion of the orbiting scroll 1,
A dashpot (a mechanism having a viscous property or a damping mechanism having a damping coefficient equal to or more than the critical damping coefficient Cc of the orbiting scroll) 5 is attached so as to pass through the inside of the bearing boss 1b provided at the center. I have. At the tip of the piston (moving body) 5a of the dash pot 5,
An electromagnet 6 that electromagnetically attracts the bottom surface of the bearing boss 1b is attached. The electromagnet 6 is turned on and off by an external control device, for example, an NC device (not shown) of a machine tool.
The off control is possible, and during processing, the bottom surface of the bearing boss 1b functions as a magnet for electromagnetically attracting.

A dashpot (a mechanism having a viscous characteristic or a shock absorbing mechanism having a damping coefficient equal to or greater than the critical damping coefficient Cc of the orbiting scroll) 5 is preferably a cylinder 5b in which a fluid 5d such as oil is sealed and a fluid 5d passing therethrough. And a piston (moving body) 5a having a plurality of holes 5c of the size The electromagnet 6 is attached to the tip of the piston 5a. Therefore, dashpot 5 is
A reaction force proportional to the speed of movement is generated by utilizing the viscosity of a fluid 5d such as oil sealed inside, and after a sufficient time has elapsed after fixing the orbiting scroll to the chuck,
No force for deforming the orbiting scroll is generated.
Therefore, even if there is a variation in the thickness of the head plate 1a, the use of the dashpot 5 allows the scroll to be supported without deformation. That is, after fixing the outer peripheral portion of the orbiting scroll 1 to the chuck, the electromagnet 6
Piston 5a by electromagnetic attraction force by turning on
And the electromagnet 6 is gradually moved due to the force applied thereto, and the electromagnet 6 is supported in close contact with the bottom surface of the bearing boss 1b, so that no force for deforming the orbiting scroll is generated. However, the dashpot 5 generates a reaction force against the vibration displacement caused by the intermittent force when cutting is performed by the cutting tool 2 such as an end mill. In addition, since the dashpot 5 is in close contact with the orbiting scroll by the electromagnet 6, a reaction force can be generated even with respect to a vibration displacement that causes the orbiting scroll 1 to rise from the chuck. Therefore, it is expected that the scroll will be more accurate and the machining efficiency will be improved due to the reduction of the deformation and the damping of the vibration in the cutting process of the end mill or the like. The processing method described above can be applied to the vortex side surface processing shown in FIG. 8A, the bottom surface processing shown in FIG. 8B, the tooth tip surface processing shown in FIG.

As shown in FIG. 3, the axial deformation of the orbiting scroll 1 is considered as a disk whose outer periphery is fixed.
In the figure, when a load of W (kg) is applied to the center of a disk having a radius a (mm) and a thickness t (mm), the displacement δ (mm) of the center of the disk is expressed by the following equation (1). It is expressed by the relationship. δ = (3 (1-ν) (3 + ν) a ² W) / (4πEt ³ ) (Equation 1) where ν is Poisson's ratio of the material of the disk, and E is Young's modulus. The thickness t of the disk is, for example, t = 11 mm, and the radius a is a
= 64 mm, Poisson's ratio ν = 0.3, Young's modulus E = 21000 kgf / mm ² ,
The equation becomes the following (Equation 2).

W = 12367δ (Equation 2) As shown in FIG. 4, when this disk is considered as a spring having a spring constant k, the spring constant is k = 12000 (kgf / m
m). The natural vibration mode of the orbiting scroll head in the conventional fixing method shown in FIG. 10 can be regarded as a spring system having a mass m (kg) and a spring constant k (kgf / mm) as shown in FIG. it can. Assuming that the natural frequency of this system is ωn, it is expressed by the following equation (3). ωn = √ (k / m) (Equation 3) With the orbiting scroll 1 actually fixed to the chuck,
When the natural frequency is measured, the following equation (4) is obtained. Therefore, the mass m (kg) becomes the value represented by the following equation (5). ωn = 6200 (rad / s) (Equation 4) m = 3.1 kg (Equation 5) That is, the first-order natural vibration mode in the conventional fixing method has a spring constant of about k = 12000 (kgf / mm), It can be considered as a spring-mass system having a mass of about m = 3.1 kg.

Next, as shown in FIG. 1, when the center of the orbiting scroll 1 is supported by the dashpot 5, the vibration mode of the end plate 1a is, as shown in FIG.
A dashpot-mass system can be considered. It is known that the critical damping coefficient Cc of this system is represented by the following (Equation 6). Cc = 2√ (mk) (Equation 6) In the system of FIG. 5, if the value of c is set to a value equal to or greater than the critical damping coefficient Cc, the system does not vibrate. The vibration amplitude x
FIG. 6 shows a response characteristic of the displacement δ of the mass when a forced vibration having a frequency of 0 or ω is given. Therefore, the above model is used as a guide for the characteristics of the dashpot (a mechanism having a viscous property or a damping mechanism having a damping coefficient equal to or greater than the critical damping coefficient Cc of the orbiting scroll) 5 for preventing the end plate 1a of the orbiting scroll 1 from vibrating. , Cc are calculated, the values are given by the following equation (7).

Cc = 390 (Equation 7) Accordingly, in a chuck for fixing the orbiting scroll having a radius of, for example, 64 mm and a thickness of, for example, 11 mm, the end plate 1 a has a critical damping coefficient Cc of about equal to or more than Equation (7). By supporting the center portion of the end plate 1a with the dashpot 5 having the damping characteristic, the end plate 1a does not vibrate in the first natural vibration mode in which the center portion of the end plate 1a is an antinode of vibration. For this reason, even if intermittent cutting is performed by the cutting tool 2 such as an end mill, the vibration is attenuated by the dash pot 5, and the shape accuracy (the flatness of the tooth tip surface 1e is about 4 μm) can be improved. That is, by improving the flatness of the mirror plate surface 1a and the tooth tip surface 1e of the orbiting scroll 1 and the fixed scroll 10 and the accuracy of the vortex contour on the tooth side surface, the gap between the teeth of the orbiting scroll 1 and the teeth of the fixed scroll 10 is reduced. Even if the diameter is about 40 μm, the teeth can be prevented from contacting each other even if the diameter is reduced by about 10 μm or more. As a result, the sealing performance of the compression chamber 11 composed of the orbiting scroll 1 and the fixed scroll 10 is improved, and the compression performance is improved. Can be realized.

FIG. 7 shows the difference in power consumption index between the prior art and the present invention. That is, according to the processing method according to the present invention, the flatness of the end surface 1e and the tip surface 1e of the orbiting scroll 1 and the accuracy of the vortex contour on the tooth side surface are improved, so that the flatness of the tip surface 1e is 4 μm. Power consumption index from 100 to about 96.5 to about 3.5 as compared with the conventional case where the flatness of the tooth tip surface 1e is only 7 μm. .
Further, as described above, in order to suppress occurrence of chatter vibration, for example, the rotation speed of the end mill 2 is set to 10,000 mi.
The processing efficiency can be improved by increasing to about n ~ ^1, and as a result, the processing time can be reduced by about 30 to 40%.

FIG. 10 is a view for explaining another embodiment of the method of machining the orbiting scroll according to the present invention. That is, in this embodiment, the outer peripheral portion of the orbiting scroll 1 is fixed similarly to the embodiment shown in FIG.
This is a method of fixing the center of the orbiting scroll 1 by holding the boss 1b for bearing provided at the center of the orbiting scroll 1 by the chuck 15. In the case of this embodiment, chatter vibration cannot be suppressed, but elastic deformation of the central portion of the orbiting scroll can be prevented.

[0020]

According to the present invention, the gap between the teeth of the orbiting scroll and the teeth of the fixed scroll can be improved by improving at least the flatness of the end surface and the tip surface of the orbiting scroll and the accuracy of the vortex contour on the tooth side. Can prevent the teeth from coming into contact with each other even if the size of the scroll is reduced. As a result, the sealing performance of the compression chamber composed of the orbiting scroll and the fixed scroll is improved, thereby realizing a scroll compressor with improved compression performance. The effect that can be achieved. Further, according to the present invention, the gap between the teeth of the orbiting scroll and the teeth of the fixed scroll can be reduced by improving at least the flatness of the end surface of the orbiting scroll and the tip surface of the orbit, and the accuracy of the vortex contour on the tooth side. Can prevent the teeth from coming into contact with each other,
As a result, it is possible to improve the sealing performance of the compression chamber formed by the orbiting scroll and the fixed scroll, improve the compression performance, and achieve a scroll compressor with reduced power consumption. Further, according to the present invention, even if the number of revolutions of the end mill is increased, machining can be performed without generating chatter vibration, machining time can be reduced, and the flatness of the tooth tip surface is 4 μm or less, which is about 5 μm or less. It became possible to improve.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view for explaining one embodiment of a method for processing an orbiting scroll according to the present invention.

FIG. 2 is a view showing one embodiment of a dashpot according to the present invention.

FIG. 3 is a diagram modeling a first-order natural vibration mode of the orbiting scroll head plate;

FIG. 4 is a diagram modeling a first-order natural vibration mode of the orbiting scroll head plate;

FIG. 5 is a diagram modeling a method according to the present invention for supporting a center portion of a head plate with a dashpot.

FIG. 6 is a diagram showing response characteristics of a system when a characteristic of a dashpot is a critical damping coefficient of the system.

FIG. 7 is a diagram showing the relationship between the tooth flatness of the orbiting scroll according to the present invention and the power consumption index of the scroll compressor.

FIG. 8 is a view showing a processing method and processing steps of the orbiting scroll according to the present invention.

FIG. 9 is a view for explaining a scroll compressor according to the present invention.

FIG. 10 is a partial cross-sectional view for explaining another embodiment of the method for machining the orbiting scroll according to the present invention.

FIG. 11 is a partial cross-sectional view for explaining a conventional technique.

FIG. 12 is a view showing an elastic deformation of the orbiting scroll that occurs when the tip surface of the orbiting scroll is processed in the related art.

FIG. 13 is a diagram showing elastic deformation of the orbiting scroll that occurs when the tooth side surface of the orbiting scroll is machined in the related art.

[Explanation of symbols]

Reference numeral 1: rotating crawl, 1a ... end plate, 1b ... boss, 1c ...
Tooth, 1d: Keyway, 1e: Tooth surface, 2: Cutting tool (end mill), 3: Chuck pulling claw, 4: Backing plate, 5: Dashpot (mechanism or cushioning mechanism having viscosity characteristics), 5a: Piston (Moving body), 5b: cylinder, 5c: hole, 5d: fluid, 6: magnet (electromagnet), 1
0: fixed scroll, 11: compression chamber, 12: discharge hole, 15: chuck.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshitake Aoki 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Inside the Air Conditioning Systems Division, Hitachi, Ltd. (72) Inventor Yukio Maeda 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture F-term in the Manufacturing Technology Laboratory (Reference) 3C022 AA01 AA07 AA08 AA09 AA10 EE05 EE11 EE12 EE15 EE17 QQ03

Claims (10)

[Claims] 1. An outer peripheral portion is fixed with reference to a processing reference plane provided on a back surface of a mirror plate in a turning scroll for processing, and a center portion of a mirror plate of the turning scroll for processing is connected to a dashpot. While supported by the moving body,
A method for machining a orbiting scroll, wherein at least a swirl side surface of the orbiting scroll to be machined is cut by rotating a cutting tool. 2. An orbiting scroll for processing has an outer peripheral portion fixed with reference to a processing reference surface provided on the back surface of the end plate, and a center portion of the end plate of the orbiting scroll for processing has a viscosity characteristic. A method of machining a orbiting scroll, wherein at least the vortex side surface of the orbiting scroll to be machined is cut by rotating a cutting tool in a state of being supported by a moving body of a mechanism having the mechanism. 3. The processing orbiting scroll is fixed with reference to a processing reference plane provided on the back surface of the end plate of the processing orbiting scroll, and the center of the processing orbiting scroll end plate is further fixed to the processing orbit. In a state where the cutting tool is rotated, at least the vortex side surface of the orbiting scroll for processing is cut while being supported by the moving body portion of the shock absorbing mechanism having a damping coefficient equal to or greater than the critical damping coefficient of the scroll. Orbiting scroll machining method. 4. A method for machining a orbiting scroll according to claim 1, further comprising the step of cutting a bottom surface of the orbiting scroll to be machined. 5. The orbiting scroll machining method according to claim 1, further comprising a step of cutting a tooth tip surface of the orbiting scroll to be processed. 6. A method for machining a turning scroll according to claim 1, wherein a center of a head plate of said turning scroll to be processed and said moving body are connected by a magnet. A method for machining a revolving scroll, comprising: 7. The orbiting scroll machining method according to claim 1, 2 or 3 or 4 or 5, wherein an electromagnet capable of controlling connection between a center portion of a head plate of the orbiting scroll to be processed and the moving body portion. Orbiting scroll machining method. 8. An orbiting scroll to be processed in a state where an outer peripheral portion is fixed with reference to a processing reference surface provided on the back surface of the end plate and a center portion of the end plate of the orbiting scroll to be processed is fixed. And turning the cutting tool to cut at least the vortex side surface of the orbiting scroll to be processed. 9. A compression chamber is constituted by a revolving scroll machined by the method of machining a revolving scroll machine according to claim 1, 2 or 3 or 4 or 5 or 6 or 7 or 8, and a fixed scroll. Scroll compressor. 10. A scroll compressor characterized in that a compression chamber is constituted by an orbiting scroll having a tooth tip surface flatness of about 5 μm or less and a fixed scroll.