JPWO2020165967A1 - Scroll compressor - Google Patents

Abstract

The scroll compressor includes a fixed scroll in which a fixed spiral body is erected on a fixed base plate and a swing scroll in which a swing spiral body is erected on a rocking base plate, and the fixed spiral body and the rocking spiral body are provided. The refrigerant is compressed in a compression chamber formed by meshing with and. Either the outer curve or the inner curve of the fixed spiral body and the rocking spiral body is a curve that is an involute of the base circle, and the involute angle θ and the base circle radius a in the x and y coordinate systems. Is used to obtain the curves defined by the equations (1) and (2). A function that increases the extension arm length w (θ) in equations (1) and (2) while changing in a sinusoidal or cosine wave shape with π [rad] as one cycle with respect to the extension angle θ. did. x = a ・ cоsθ + w (θ) ・ sinθ ・ ・ ・ (1) y = a ・ sinθ−w (θ) ・ cоsθ ・ ・ ・ (2)

Description

The present invention relates to a scroll compressor used in an air conditioner, a refrigerator, or the like.

A scroll compressor used in an air conditioner, a refrigerator, or the like includes a compression mechanism unit that compresses a refrigerant in a compression chamber formed by combining a fixed scroll and a swing scroll, and a container that houses the compression mechanism unit. Has a structure. Each of the fixed scroll and the swing scroll has a structure in which spiral bodies are erected on a base plate, and the spiral bodies are meshed with each other to form a compression chamber. Then, by swinging the swing scroll, the compression chamber moves while reducing the volume, and the refrigerant is sucked and compressed in the compression chamber. In this type of scroll compressor, in order to reduce the size and cost, the technology aims to increase the compression function by increasing the suction volume of the compression chamber as much as possible while keeping the diameter of the container the same. Development is important. In order to increase the suction volume of the compression chamber while keeping the diameter of the container the same, it is necessary to devise the spiral shape of the spiral body.

As the spiral shape of the scroll compressor, there is a technique in which an involute curve based on a perfect circle with a predetermined radius is used and the outline of the entire spiral body is made circular. On the other hand, in recent years, there is a technique in which the contour of the entire spiral body is not circular but flat, and the spiral shape of the spiral body is also flat (see, for example, Patent Document 1).

In the vicinity of the compression mechanism of the scroll compressor, an old dam ring having a function of preventing the rotation of the swing scroll is arranged. Considering that the key portion of the old dam ring is released, it is desirable that the outer shape of the base plate of the swing scroll is a flat shape rather than a circular shape in order to improve the mounting density of the compressor parts. When the outer shape of the base plate is flat, the spiral shape of the spiral body is also flat, so that the limited space on the base plate can be effectively used to increase the suction volume of the compression chamber. It is possible. Therefore, as in Patent Document 1, making the spiral shape of the spiral body flat is effective in increasing the suction volume of the compression chamber.

Japanese Unexamined Patent Publication No. 10-54380

Although Patent Document 1 describes that the contour and the spiral shape of the spiral body are flat, the specific definition of the spiral shape is not described. As for the spiral shape of the spiral body, as described above, there is a technique defined by an involute curve based on a perfect circle with a predetermined radius, but even when the spiral shape is a flat shape, in manufacturing the spiral body. It is necessary to specifically define the spiral shape in.

The present invention has been made in view of these points, and an object of the present invention is to provide a scroll compressor capable of defining the spiral shape of a spiral body having a flat outline by an equation.

The scroll compressor according to the present invention includes a fixed scroll in which a fixed spiral body is erected on a fixed base plate and a swing scroll in which a swing spiral body is erected on a rocking base plate. In a scroll compressor that compresses a refrigerant in a compression chamber formed by meshing with a swinging spiral, one of the outer and inner curves of the fixed spiral and the swinging spiral is an involute of the base circle. A curve that is an open line and is defined by equations (1) and (2) using the involute angle θ and the base circle radius a in the x and y coordinate systems. The involute arm length w (θ) in 2) is a function that increases while changing in a spiral or cosine wave shape with π [rad] as one cycle with respect to the involute angle θ.
x = a ・ cоsθ + w (θ) ・ sinθ ・ ・ ・ (1)
y = a ・ sinθ−w (θ) ・ cоsθ ・ ・ ・ (2)

According to the present invention, the spiral shape of the spiral body is defined by the equations (1) and (2) using the involute angle θ and the basic pi a in the x and y coordinate systems, and also the equations (1) and The involute arm length w (θ) in the equation (2) is a function that increases while changing in a sinusoidal shape or a cosine wave shape with π [rad] as one cycle with respect to the involute angle θ. Thereby, the spiral shape of the spiral body having a flat contour can be defined by the equation.
x = a ・ cоsθ + w (θ) ・ sinθ ・ ・ ・ (1)
y = a ・ sinθ−w (θ) ・ cоsθ ・ ・ ・ (2)

It is a schematic vertical sectional view of the whole structure of the scroll compressor which concerns on Embodiment 1 of this invention. It is sectional drawing of the compression mechanism part of the scroll compressor which concerns on Embodiment 1 of this invention. It is a top view which showed the fixed spiral body and the rocking spiral body of the compression mechanism part of the scroll compressor which concerns on Embodiment 1 of this invention. It is a compression process diagram which shows the operation during one rotation of a swing scroll in the scroll compressor which concerns on Embodiment 1 of this invention. It is explanatory drawing of the drawing method of the spiral shape which constitutes the compression mechanism part of the scroll compressor which concerns on Embodiment 1 of this invention. It is a figure which shows an example of the characteristic of the extension arm length w (θ) used for drawing the spiral shape of the spiral body in the scroll compressor which concerns on Embodiment 1 of this invention. It is a figure which shows the change of the flatness of the outer curve of the spiral body in the scroll compressor which concerns on Embodiment 2 of this invention. It is a figure shows the outer curve of the spiral body in the scroll compressor which concerns on Embodiment 3 of this invention. It is a figure which shows the spiral shape of the spiral body in the scroll compressor which concerns on Embodiment 4 of this invention. It is a figure which shows the characteristic of the extension arm length w (θ) which specifies the spiral shape of the spiral body in the scroll compressor which concerns on Embodiment 4 of this invention.

Hereinafter, the scroll compressor according to the embodiment of the present invention will be described with reference to the drawings and the like. Here, in the following drawings including FIG. 1, those having the same reference numerals are the same or equivalent thereto, and are common to the whole texts of the embodiments described below. The form of the component represented in the entire specification is merely an example, and is not limited to the form described in the specification.

Embodiment 1.
FIG. 1 is a schematic vertical sectional view of the overall configuration of the scroll compressor according to the first embodiment of the present invention.
The scroll compressor of the first embodiment includes a compression mechanism unit 8, an electric mechanism unit 110 that drives the compression mechanism unit 8 via a rotating shaft 6, and other components, which constitute an outer shell. It has a structure housed inside the closed container 100.

Further, the frame 7 and the subframe 9 are housed in the closed container 100 so as to face each other with the electric mechanism portion 110 interposed therebetween. The frame 7 is arranged above the electric mechanism portion 110 and is located between the electric mechanism portion 110 and the compression mechanism portion 8. The subframe 9 is located below the electric mechanism portion 110. The frame 7 is fixed to the inner peripheral surface of the closed container 100 by shrink fitting, welding, or the like. The subframe 9 is fixed to the inner peripheral surface of the closed container 100 by shrink fitting or welding via the subframe holder 9a.

Below the subframe 9, a pump element 112 including a positive displacement pump is attached. The pump element 112 supplies the refrigerating machine oil stored in the oil reservoir 100a at the bottom of the closed container 100 to a sliding portion such as a main bearing 7a described later of the compression mechanism 8. The pump element 112 supports the rotating shaft 6 in the axial direction on the upper end surface.

The closed container 100 is provided with a suction pipe 101 for sucking the refrigerant and a discharge pipe 102 for discharging the refrigerant.

The compression mechanism unit 8 has a function of compressing the refrigerant sucked from the suction pipe 101 and discharging the compressed refrigerant to the high-pressure part formed above the closed container 100. The compression mechanism unit 8 includes a fixed scroll 1 and a swing scroll 2.

The fixed scroll 1 is fixed to the closed container 100 via the frame 7. The swing scroll 2 is arranged below the fixed scroll 1 and is swingably supported by an eccentric shaft portion 6a described later of the rotation shaft 6.

The fixed scroll 1 includes a fixed base plate 1a and a fixed spiral body 1b which is a spiral protrusion erected on one surface of the fixed base plate 1a. The oscillating scroll 2 includes a oscillating base plate 2a and a oscillating spiral body 2b which is a spiral projection erected on one surface of the oscillating base plate 2a. The fixed scroll 1 and the swing scroll 2 are arranged in the closed container 100 in a symmetrical spiral shape in which the fixed spiral body 1b and the swing spiral body 2b are meshed with each other in opposite phases. A compression chamber 71 is formed between the fixed spiral body 1b and the rocking spiral body 2b, whose volume decreases from the outer side to the inner side in the radial direction as the rotation shaft 6 rotates.

The baffle 4 is fixed to the surface of the fixed base plate 1a of the fixed scroll 1 opposite to the swing scroll 2. The baffle 4 is formed with a through hole 4a communicating with the discharge port 1c of the fixed scroll 1, and the through hole 4a is provided with a discharge valve 11. A discharge muffler 12 is attached to the baffle 4 so as to cover the through hole 4a.

The frame 7 has a fixed scroll 1 arranged in a fixed manner, and has a thrust surface that supports the thrust force acting on the swing scroll 2 in the axial direction. Further, the frame 7 is formed through an opening 7c that guides the refrigerant sucked from the suction pipe 101 into the compression mechanism portion 8.

Further, an old dam ring 14 is arranged on the frame 7 to prevent the swing scroll 2 from rotating during the turning motion. The key portion 14a of the old dam ring 14 is arranged on the outer peripheral side of the rocking base plate 2a of the rocking scroll 2.

The electric mechanism unit 110 supplies a rotational driving force to the rotating shaft 6, and includes an electric motor stator 110a and an electric motor rotor 110b. The electric motor stator 110a is connected to a glass terminal (not shown) existing between the frame 7 and the electric motor stator 110a by a lead wire (not shown) in order to obtain electric power from the outside. The electric motor stator 110a is fixed to the rotating shaft 6 by shrink fitting or the like. A first balance weight 60 is fixed to the rotating shaft 6 and a second balance weight 61 is fixed to the motor stator 110a in order to balance the entire rotating system of the scroll compressor.

The rotating shaft 6 is composed of an eccentric shaft portion 6a at the upper part of the rotating shaft 6, a main shaft portion 6b, and a sub-shaft portion 6c at the lower part of the rotating shaft 6. The eccentric shaft portion 6a is fitted to the swing scroll 2 via a slider 5 with a balance weight and a swing bearing 2c, and the swing scroll 2 is swung by the rotation of the rotation shaft 6. The spindle portion 6b is fitted to the spindle portion 7a arranged on the inner circumference of the cylindrical boss portion 7b provided on the frame 7 via the sleeve 13, and slides with the spindle portion 7a via an oil film of refrigerating machine oil. To do. The main bearing 7a is fixed in the boss portion 7b by press-fitting a bearing material used for a slide bearing such as a copper-lead alloy.

An auxiliary bearing 10 made of a ball bearing is provided on the upper part of the subframe 9, and the rotating shaft 6 is pivotally supported in the radial direction on the lower part of the electric mechanism portion 110. The auxiliary bearing 10 may be pivotally supported by a bearing configuration other than the ball bearing. The sub-shaft portion 6c is fitted with the sub-bearing 10 and slides with the sub-bearing 10 via an oil film made of refrigerating machine oil. The axes of the spindle 6b and the sub-axis 6c coincide with the axes of the rotating shaft 6.

Here, the space inside the closed container 100 is defined as follows. Of the internal space of the closed container 100, the space on the motor rotor 110b side of the frame 7 is designated as the first space 72. Further, the space formed by the inner wall of the frame 7 and the fixed base plate 1a is referred to as the second space 73. Further, the space on the discharge pipe 102 side of the fixed base plate 1a is designated as the third space 74.

Next, the arrangement of the parts of the compression mechanism portion 8 inside the closed container 100 will be described.
FIG. 2 is a cross-sectional view of the compression mechanism portion of the scroll compressor according to the first embodiment of the present invention. FIG. 3 is a plan view showing a fixed spiral body and a swinging spiral body of the compression mechanism portion of the scroll compressor according to the first embodiment of the present invention. In addition, in FIGS. 2 and 3, in order to facilitate the distinction between the fixed spiral body 1b of the fixed scroll 1 and the rocking spiral body 2b of the rocking scroll 2, the swinging spiral body 2b of the rocking scroll 2 is hatched. It has been given. The same applies to the figures described later.

The closed container 100 has a perfect circular shape when viewed in a plane, and is fixed to the inside of the closed container 100 in a state where the outer peripheral surface of the frame 7 is in contact with the inner peripheral surface of the closed container 100. Therefore, the outer peripheral surface of the frame 7 also has a perfect circular shape. In the second space 73 inside the frame 7, the fixed spiral body 1b of the fixed scroll 1 and the swing scroll 2 are arranged. Further, the key portion 14a of the old dam ring 14 is arranged in the second space 73. In such a specification, since it is necessary to arrange the rocking base plate 2a while avoiding the movable range of the key portion 14a, the outer shape of the rocking base plate 2a is flat. The flat shape also includes an oval shape and an elliptical shape, and in short, refers to all shapes that are flatter than a circle.

Since the outer shape of the rocking base plate 2a is flat in this way, the swinging spiral body 2b erected on the rocking base plate 2a is also made flat so as to be on the rocking base plate 2a. Space can be used effectively and space efficiency can be improved. The same applies to the fixed base plate 1a, and the fixed base plate 1a and the fixed spiral body 1b have a flat shape. By increasing the space efficiency in this way, it is possible to increase the volume of the compression chamber 71 while keeping the size of the closed container 100 the same, and it is possible to improve the compression function force. On the contrary, in order to secure the same compression function force, the size of the closed container 100 can be reduced. In the following, when the fixed spiral body 1b and the rocking spiral body 2b are not distinguished and both are referred to, they are collectively referred to as "spiral body". The same applies to the base plate, and when the fixed base plate 1a and the swing base plate 2a are not distinguished and both are referred to, they are collectively referred to as "base plate".

Next, the operation of the scroll compressor will be described.

FIG. 4 is a compression process diagram showing the operation of the swing scroll during one rotation in the scroll compressor according to the first embodiment of the present invention. FIG. 4A shows the position of the spiral body when the rotation phase is 0 [rad] (2π [rad]). FIG. 4B shows the position of the spiral body when the rotation phase is π / 2 [rad]. FIG. 4C shows the position of the spiral body when the rotation phase is π [rad]. FIG. 4D shows the position of the spiral body when the rotation phase is 3π / 2 [rad].

When the electric motor stator 110a of the electric mechanism unit 110 is energized, the electric motor rotor 110b receives rotational force and rotates. Along with this, the rotating shaft 6 fixed to the electric motor rotor 110b is rotationally driven. The rotational motion of the rotating shaft 6 is transmitted to the swing scroll 2 via the eccentric shaft portion 6a. The oscillating spiral body 2b of the oscillating scroll 2 oscillates with an oscillating radius while its rotation is regulated by the old dam ring 14. The swing radius means the amount of eccentricity of the eccentric shaft portion 6a with respect to the spindle portion 6b.

As the electric mechanism unit 110 is driven, the refrigerant flows from the external refrigeration cycle into the first space 72 in the closed container 100 via the suction pipe 101. The low-pressure refrigerant that has flowed into the first space 72 flows into the second space 73 through the two openings 7c installed in the frame 7. The low-pressure refrigerant that has flowed into the second space 73 is sucked into the compression chamber 71 along with the relative swinging motion of the swinging spiral body 2b and the fixed spiral body 1b of the compression mechanism unit 8. As shown in FIG. 4, the refrigerant sucked into the compression chamber 71 is boosted from low pressure to high pressure due to the geometric volume change of the compression chamber 71 accompanying the relative operation of the swinging spiral body 2b and the fixed spiral body 1b. Will be done. Then, the high-pressure refrigerant passes through the discharge port 1c of the fixed scroll 1 and the through hole 4a of the baffle 4, pushes the discharge valve 11 open, and is discharged into the discharge muffler 12. The refrigerant discharged into the discharge muffler 12 is discharged into the third space 74, and is discharged from the discharge pipe 102 to the outside of the compressor as a high-pressure refrigerant.

In the first embodiment, as described above, the contours of the swinging spiral body 2b and the fixed spiral body 1b are flat, and the spiral shape is also flat. As described above, in the compression mechanism unit 8 in which the spiral shape of the spiral body is flat, even when the swing spiral body 2b is operated with a constant swing radius as shown in FIG. 4, the swing spiral body 2b The outward and inward surfaces of the fixed spiral body 1b operate while contacting the inward and outward surfaces of the fixed spiral body 1b.

The first embodiment is characterized in that the spiral shape of the spiral body having a flat contour is defined by an equation. The shape of the spiral is determined by an outer curve that identifies the outward surface of the spiral and an inner curve that identifies the inward surface of the spiral. In defining the spiral shape of the spiral body by the equation, specifically, either the outer curve or the inner curve of the spiral body is a curve that is an involute of the base circle, and is in the x, y coordinate system. The curve defined by the equations (1) and (2) is obtained by using the involute angle θ.

In equations (1) and (2), a is the radius of the base circle. The extension arm length w (θ) in the equations (1) and (2) is a point on the curve at the extension angle θ of the involute from a point on the circumference of the base circle at the extension angle θ. It is the length of a straight line connecting the two, and is given by a function that changes in a sinusoidal or involute shape with π [rad] as one cycle. Thereby, the spiral shape of the spiral body having a flat outline can be defined by the equation. The involute arm length w (θ) changes in a sinusoidal shape or a cosine wave shape as described above, but in the first embodiment, as an example, it changes in a sinusoidal shape as shown in the equation (3). Let's assume. In the equation (3), α and β are coefficients. N is a natural number of 1 or more.

In equation (3), α holds whether it has a positive value or a negative value. β is a positive value. By changing α, the flatness of the contour changes. In addition, by changing β, the reduction rate of the wall thickness of the spiral body changes. Specific changes in the spiral body when α and β are changed will be described in the second and third embodiments.

Next, a drawing method of each spiral shape of the fixed spiral body 1b and the swinging spiral body 2b will be described. Since the drawing method of the fixed spiral body 1b and the swinging spiral body 2b is the same, the swinging spiral body 2b will be described below as a representative. The shape of the spiral is determined by an outer curve that specifies the outward surface of the spiral body and an inner curve that specifies the inward surface of the spiral body as described above. Here, a method of drawing a spiral shape when the outer curve is a curve defined by the equations (1) and (2) will be described with reference to FIG.

FIG. 5 is an explanatory diagram of a spiral-shaped drawing method constituting the compression mechanism portion of the scroll compressor according to the first embodiment of the present invention. In FIG. 5, drawings are drawn according to the procedures (a), (b), (c), and (d). In drawing, first, as shown in FIG. 5A, an involute 30 of the base circle is drawn. Here, the extension arm length w (θ) increases in a sinusoidal manner with π [rad] as one cycle according to the extension angle θ as described above. The involute 30 drawn here is the outer curve.

Next, the inner curve is drawn by the procedure of FIGS. 5 (b) to 5 (d). That is, first, as shown in FIG. 5B, a curve 31 is drawn by rotating the involute 30 drawn in the procedure (a) by π [rad] with respect to the center of the base circle O. Here, since the inner curve is created, the curved portion (dotted line portion in FIG. 5B) located outside the curve 30 of the curve 31 is not used in the subsequent drafting procedure.

Next, as shown in FIG. 5C, a plurality of circles 32 having a center on the curve 31 drawn in the procedure (b) and having a radius equal to the swing radius of the swing scroll 2 are drawn. Next, as shown in FIG. 5D, the outer envelope 33 of the circle group drawn in the procedure (c) is drawn. The curve 33 drawn in this procedure (d) becomes the inner curve.

As described above, the curve 30 drawn in the procedure (a) becomes the outer curve of the oscillating spiral body 2b, the curve 33 drawn in the procedure (d) becomes the inner curve of the oscillating spiral body 2b, and the hatching area of the procedure (d). Is the cross section of the swinging spiral body 2b. In FIG. 5, the extension arm length w (θ) is a oscillating spiral when the value of α is 0.5, the value of β is 0.015, and the value of N is 1 in the equation (3). The shape of the body 2b is described.

For the fixed spiral body 1b, the same procedure as that for the rocking spiral body 2b described above was adopted, and the shape of the rocking spiral body 2b was rotated by π [rad] in the specification having the same wall thickness as the rocking spiral body 2b. It becomes a shape.

Here, the method of drawing the spiral shape when the outer curve is the curve defined by the equations (1) and (2) has been described, but the inner curve is defined by the equations (1) and (2). The method of drawing a spiral shape in the case of a curved line is basically the same. When the inner curve is the curve defined by the equations (1) and (2), the outer curve may be drawn as follows. First, the procedure shown in FIG. 5A is performed, and then the curved portion of the curve 30 located outside the curve 31 in FIG. 5B is not used in the subsequent drawing procedure. Then, a plurality of circles 32 having a center on the curve 31 and having a radius equal to the swing radius of the swing scroll 2 are drawn. The inner envelope of this circle group becomes the outer curve.

FIG. 6 is a diagram showing an example of the characteristics of the extension arm length w (θ) used for drawing the spiral shape of the spiral body in the scroll compressor according to the first embodiment of the present invention. The vertical axis of FIG. 6 shows the ratio of w (θ) to the product of the radius of the base circle a and the extension angle θ. The horizontal axis of FIG. 6 indicates the extension angle θ [rad].

FIG. 6 shows the extension arm length with respect to the extension angle θ when the value of α in the equation (3) is 0.5, the value of β is 0.015, and the value of N is 1, as in FIG. It shows the periodic change of w (θ). In the waveform of the extension arm length w (θ) shown in FIG. 6, it is shown that the larger the value of w (θ) / a · θ, the thicker the wall thickness of the spiral body. Therefore, the wall thickness of the spiral body becomes thicker at π / 2, 3π / 2, 5π / 2, and 7π / 2. Further, in the waveform of the involute arm length w (θ), the spiral body is stretched in the direction of the involute angle where the peak exceeding 1.0 is present. Therefore, in the example of FIG. 6, when the involute angles are π / 2, 3π / 2, 5π / 2, and 7π / 2, the peak exceeding 1.0 comes, and therefore, as shown in FIG. 5, in the lateral direction. It has a stretched shape.

When β is 0, the peak period of the involute arm length w (θ) is π [rad]. Here, since β is 0.015 and is 0 or more, the period of the peak of the involute arm length w (θ) is slightly shorter than π [rad]. When β is 0 or less, the peak period of the involute arm length w (θ) is slightly longer than π [rad]. In this way, the period of the involute arm length w (θ) may deviate from π [rad] depending on the value of β, but the deviation is slight. Therefore, the expression "the extension arm length w (θ) changes in a sinusoidal shape with π [rad] as one period with respect to the extension angle θ" is expressed when the period matches π [rad]. Not only, but also the case where there is a slight deviation.

As described above, in the first embodiment, the spiral shape of the spiral body is defined by the above equations (1) and (2) using the extension angle θ. Then, the extension arm length w (θ) in the equations (1) and (2) is a function that changes in a sinusoidal shape or a cosine wave shape with π [rad] as one cycle with respect to the extension angle θ. .. Thereby, the spiral shape of the spiral body having a flat contour can be defined by the equation.

Further, since the spiral body according to the first embodiment has a flat outline together with the base plate, the mounting density of the spiral body on the base plate can be improved. In the past, there was a technology in which the contours of both the base plate and the spiral body were made into a perfect circle, but by improving the mounting density of the spiral body compared to this conventional technology, the overall length of the spiral of the spiral body can be set longer. It becomes possible to do. Since the total length of the spiral of the spiral body can be increased, the area of the entire tip surface in the axial direction of the spiral body can be set large. Some scroll compressors have a compliant mechanism that brings the fixed scroll 1 and the swing scroll 2 into axial contact with each other, but even in this type of scroll compressor, the surface pressure generated on the tip surface of the spiral body is applied. Can be reduced. Therefore, wear and seizure due to sliding can be suppressed, and reliability can be improved.

Further, in the spiral shape of the spiral body described in the first embodiment, the rotation phases of 0 and π are more sliding on the side surface of the spiral body than the rotation phases of π / 2 and 3π / 2 in FIG. The speed can be set low. Therefore, by setting the sliding speed small in the rotation phase where the gas load in the horizontal direction is large and setting the sliding speed large in the rotation phase where the gas load in the horizontal direction is small, the PV value on the side surface of the spiral body is set. Can be reduced. The PV value is the product of the load and the sliding speed. Since the PV value can be reduced in this way, wear and seizure due to sliding can be suppressed, and reliability can be improved.

Embodiment 2.
In the second embodiment, the change in the flatness of the contour of the spiral body according to the value of α in the above formula (3) will be described. Hereinafter, the configuration in which the second embodiment is different from the first embodiment will be mainly described, and the configurations not described in the second embodiment are the same as those in the first embodiment.

In the above equation (3), the shape of the spiral body when the value of α is changed is shown in FIG. 7 below.

FIG. 7 is a diagram showing a change in the flatness of the outer curve of the spiral body in the scroll compressor according to the second embodiment of the present invention. In FIG. 7, (a) shows the case of α = 0, (b) shows the case of α = 0.1, and (c) shows the case of α = 0.2. Further, in FIG. 7, the value of β is fixed at 0.005, and the value of N is fixed at 1.

By changing the value of α as shown in FIG. 7, it is possible to arbitrarily set the flatness of the contour of the spiral body. The flatness is the ratio D1 / D2 of the major axis D1 and the minor axis D2 as shown in FIG. 7A. Therefore, as shown in FIG. 7, the flattening ratio increases as the value of α increases.

According to the second embodiment, the same effect as that of the first embodiment can be obtained, and the flatness of the contour of the spiral body can be arbitrarily set by changing the value of α. Therefore, by changing α according to the shape of the base plate and setting the flatness of the contour of the spiral body, the contour of the spiral body is optimized and the mounting density of the spiral body on the base plate is improved. be able to.

Embodiment 3.
In the third embodiment, the change in the reduction rate of the wall thickness of the spiral body according to the value of β in the above formula (3) will be described. Hereinafter, the configuration in which the third embodiment is different from that of the first embodiment will be mainly described, and the configurations not described in the third embodiment are the same as those in the first embodiment.

In the above equation (3), the shape of the spiral body when the value of β is changed is shown in FIG. 8 below.

FIG. 8 is a diagram showing an outer curve of a spiral body in the scroll compressor according to the third embodiment of the present invention. In FIG. 8, (a) shows the case of β = 0, (b) shows the case of β = 0.005, and (c) shows the case of β = 0.010. Further, in FIG. 8, the value of α is fixed at 0.2 and the value of N is fixed at 1.

By changing the value of β as shown in FIG. 8, it is possible to arbitrarily set the reduction rate of the interval from the winding start portion to the winding end portion of the spiral body. As shown in FIG. 8A, the reduction rate of the interval is a ratio P1 / P2 of the interval P1 at the start of winding and the interval P2 at the end of winding. Therefore, as shown in FIG. 8, as β increases at 0 or more, the reduction rate of the interval increases. The reduction rate of the wall thickness of the spiral body also increases as β increases at 0 or more, similar to the reduction rate of the interval. The wall thickness reduction ratio is the ratio of the wall thickness at the start of winding and the wall thickness at the end of winding of the spiral body.

In the above equation (3), β takes a value of 0 or more, and when β is increased, the value of (1-βθ) in the equation (3) decreases as the extension angle θ increases. Therefore, as is clear from FIG. 6, the value of w (θ) / a · θ becomes smaller every π from the extension angle θ. Specifically, w (θ) / a · θ is about 1.46 when the extension angle θ is π / 2, but w (θ) / a · θ when the extension angle θ is 3π / 2. Is about 1.39, which is smaller. Then, as described above, when w (θ) / a · θ is large, it indicates that the wall thickness of the spiral body is thick, so that when the involute arm length w (θ) changes as shown in FIG. From the beginning to the end of winding, the wall thickness of the spiral body is reduced by the involute angle π. The effect obtained by this configuration will be described below.

The pressure difference between the compression chambers 71 formed in the compression mechanism portion 8 becomes larger toward the central portion where the refrigerant is compressed and the pressure becomes higher, that is, the central portion of the spiral body. That is, the pressure difference between the compression chambers 71 is larger in the winding start portion of the spiral body than in the winding end portion. Therefore, when designing the wall thickness of the spiral body, it is necessary to design the wall thickness so as to withstand the pressure difference generated in the central portion of the spiral body. Here, assuming that the wall thickness of the spiral body is constant from the start to the end of winding with a wall thickness that can withstand the pressure difference generated at the center of the spiral body, the winding end with a small pressure difference between the compression chambers 71. In the vicinity of the part, the strength is excessively designed. That is, since the wall thickness of the spiral body is formed to be thicker than necessary, the volume of the compression chamber 71 at the completion of suction, that is, the suction volume is unnecessarily reduced.

On the other hand, in the third embodiment, the reduction rate of the wall thickness from the winding start portion to the winding end portion can be arbitrarily set by appropriately setting β. For this reason, by setting β according to the specifications and operating conditions of the compressor, the wall thickness is reduced at the end of winding while maintaining the strength required at the beginning of winding, and within a limited space. It is possible to obtain a spiral body capable of securing a large suction volume. Specifically, as β increases with a value of 0 or more, the reduction rate of the wall thickness increases. Therefore, when the pressure difference between the compression chambers 71 at the center of the spiral body is large, the value of β increases. However, when the pressure difference between the compression chambers 71 at the center of the spiral body is small, the value of β may be reduced.

As described above, according to the third embodiment, the same effect as that of the first embodiment can be obtained, and the reduction rate of the wall thickness of the spiral body can be arbitrarily set by changing the value of β. It becomes possible.

Further, by combining the third embodiment with the second embodiment, it is possible to define a specific mathematical formula that can arbitrarily set the flatness of the contour of the spiral body and the reduction rate of the wall thickness, and the spiral body on the base plate. The degree of freedom in designing the spiral shape can be improved. Then, by setting the flatness of the contour of the spiral body according to the shape of the base plate and setting β according to the specifications of the compressor and the operating conditions, the contour of the spiral body is optimized. It is possible to increase the suction volume while improving the mounting density. This makes it possible to improve the compression function without increasing the size of the compressor. Alternatively, the compressor can be miniaturized with the same compression function.

Embodiment 4.
In the fourth embodiment, the change in the spiral shape according to the characteristic of the extension arm length w (θ) will be described. Hereinafter, the configuration in which the fourth embodiment is different from the first embodiment will be mainly described, and the configurations not described in the fourth embodiment are the same as those in the first embodiment.

FIG. 9 is a diagram showing a spiral shape of a spiral body in the scroll compressor according to the fourth embodiment of the present invention. 9 (a) to 9 (d) show, in order, the functional formulas of the extended arm length w (θ), the formula (3) shown in the first embodiment, and the following formulas (4) to (4). The shapes of the fixed spiral body 1b and the rocking spiral body 2b in the case of (6) are described. FIG. 10 is a diagram showing the characteristics of the extension arm length w (θ) that specifies the spiral shape of the spiral body in the scroll compressor according to the fourth embodiment of the present invention. 10 (a) to 10 (d) correspond to FIGS. 9 (a) to 9 (d), and the involute arm length w (θ) is shown in the first embodiment in order. The equations (3) and the following equations (4) to (6) are used. The vertical axis of FIG. 10 shows the ratio of w (θ) to the product of the radius of the base circle a and the extension angle θ. The horizontal axis of FIG. 10 indicates the extension angle θ [rad]. Further, in FIGS. 9 and 10, the value of α is 0.1, the value of β is 0, and the value of N is 1.

As shown in FIG. 9, by changing the functional expression of the extension arm length w (θ), the contours of the fixed spiral body 1b and the swinging spiral body 2b can be arbitrarily set.

In the first to fourth embodiments, the low pressure shell type scroll compressor in which the inside of the closed container 100 is filled with the low pressure refrigerant is shown, but the high pressure shell type scroll compressor in which the inside of the closed container 100 is filled with the high pressure refrigerant is shown. Even in the case of, the same effect can be obtained.

1 Fixed scroll, 1a Fixed base plate, 1b Fixed spiral body, 1c Discharge port, 2 Swing scroll, 2a Swing base plate, 2b Swing spiral body, 2c Swing bearing, 4 Baffle, 4a Through hole, 5 Balance weight With slider, 6 rotation shaft, 6a eccentric shaft part, 6b main shaft part, 6c sub-shaft part, 7 frame, 7a main bearing, 7b boss part, 7c opening, 8 compression mechanism part, 9 subframe, 9a subframe holder, 10 Sub-bearing, 11 Discharge valve, 12 Discharge muffler, 13 Sleeve, 14 Oldam ring, 14a key part, 21 Overcompression relief port, 22 Overcompression relief port, 30 Extension wire, 32 yen, 33 Outer envelope wire, 60th 1 Balance weight, 61 2nd balance weight, 71 Compression chamber, 72 1st space, 73 2nd space, 74 3rd space, 100 Sealed container, 100a Oil reservoir, 101 Suction pipe, 102 Discharge pipe, 110 Electric mechanism , 110a motor stator, 110b motor rotor, 112 pump elements.

The scroll compressor according to the present invention includes a fixed scroll in which a fixed spiral body is erected on a fixed base plate and a swing scroll in which a swing spiral body is erected on a rocking base plate. In a scroll compressor that compresses a refrigerant in a compression chamber formed by meshing with a swinging spiral, one of the outer and inner curves of the fixed spiral and the swinging spiral is an involute of the base circle. A curve that is an open line and is defined by equations (1) and (2) using the involute angle θ and the base circle radius a in the x and y coordinate systems. The involute arm length w (θ) in 2) is a function that increases while changing in a spiral or cosine wave shape with π [rad] as one cycle with respect to the involute angle θ , and equations (1) and equations (1) and equations. When the curve defined in (2) is an outer curve, the inner curves of the fixed spiral body and the rocking spiral body are on a curve obtained by rotating the outer curve by π [rad] with respect to the center of the base circle. Fixed spirals and swings when the outer involute of a group of circles with a center whose radius is equal to the swing radius of the swing scroll and the curves defined by equations (1) and (2) are inner curves. Each outer curve of the dynamic spiral has a center on a curve obtained by rotating the inner curve by π [rad] with respect to the center of the base circle, and the inner envelopment of a group of circles whose radius is equal to the swing radius of the swing scroll. It is a line .
x = a ・ cоsθ + w (θ) ・ sinθ ・ ・ ・ (1)
y = a ・ sinθ−w (θ) ・ cоsθ ・ ・ ・ (2)

The scroll compressor according to the present invention includes a fixed scroll in which a fixed spiral body is erected on a fixed base plate and a swing scroll in which a swing spiral body is erected on a rocking base plate. In a scroll compressor that compresses a refrigerant in a compression chamber formed by meshing with a swinging spiral, one of the outer and inner curves of the fixed spiral and the swinging spiral is an involute of the base circle. An involute curve that is defined by equations (1) and (2) using the involute angle θ and the base circle radius a in the x and y coordinate systems, and equations (1) and (1). The involute arm length w (θ) in 2) is a function that increases while changing in a sinusoidal or involute shape with π [rad] as one cycle with respect to the involute angle θ, and equations (1) and equations (1) and equations. When the curve defined in (2) is an outer curve, the inner curves of the fixed spiral body and the swinging spiral body are on a curve obtained by rotating the outer curve by π [rad] with respect to the center of the base circle. Fixed spirals and swings when the outer involute of a group of circles with a center whose radius is equal to the swing radius of the swing scroll and the curves defined by equations (1) and (2) are inner curves. Each outer curve of the dynamic spiral has a center on a curve obtained by rotating the inner curve by π [rad] with respect to the center of the base circle, and the inner envelopment of a group of circles whose radius is equal to the swing radius of the swing scroll. By making it a line, the outer shape of the entire swinging spiral body is made flatter than the outer shape of the spiral body using the involute curve, and the outer shape of the rocking base plate is flattened according to the outer shape of the swinging spiral body. It is said to be .
x = a ・ cоsθ + w (θ) ・ sinθ ・ ・ ・ (1)
y = a ・ sinθ−w (θ) ・ cоsθ ・ ・ ・ (2)

The scroll compressor according to the present invention includes a fixed scroll in which a fixed spiral body is erected on a fixed base plate and a swing scroll in which a swing spiral body is erected on a rocking base plate. In a scroll compressor that compresses a refrigerant in a compression chamber formed by meshing with a swinging spiral, one of the outer and inner curves of the fixed spiral and the swinging spiral is an involute of the base circle. An involute curve that is defined by equations (1) and (2) using the involute angle θ and the base circle radius a in the x and y coordinate systems, and equations (1) and (1). The involute arm length w (θ) in 2) is a function that increases while changing in a sinusoidal or involute shape with π [rad] as one cycle with respect to the involute angle θ, and equations (1) and equations (1) and equations. When the curve defined in (2) is an outer curve, the inner curves of the fixed spiral body and the rocking spiral body are on a curve obtained by rotating the outer curve π [rad] with respect to the center of the base circle. Fixed spirals and rocks when the outer involute of a group of circles with a center whose radius is equal to the swing radius of the swing scroll and the curves defined by equations (1) and (2) are inner curves. Each outer curve of the dynamic spiral has a center on a curve obtained by rotating the inner curve by π [rad] with respect to the center of the base circle, and the inner envelopment of a group of circles whose radius is equal to the swing radius of the swing scroll. By making it a line, the outer shape of the entire swinging spiral body is made flatter than the outer shape of the spiral body using the involute curve, and the wall thickness of the fixed spiral body and the swinging spiral body is the involute arm length w. The value of (θ) changes periodically so as to increase at the involute angle θ, which increases periodically .
x = a ・ cоsθ + w (θ) ・ sinθ ・ ・ ・ (1)
y = a ・ sinθ−w (θ) ・ cоsθ ・ ・ ・ (2)

Claims (8)

A fixed scroll in which a fixed spiral body is erected on a fixed base plate and a swing scroll in which a swing spiral body is erected on a swing base plate are provided, and the fixed spiral body and the swing spiral body mesh with each other. In a scroll compressor that compresses the refrigerant in the compression chamber formed by
One of the outer curve and the inner curve of the fixed spiral body and the rocking spiral body is an involute of the base circle, and the involute angle θ and the base circle in the x and y coordinate systems. The radius a is used as a curve defined by the equations (1) and (2), and the involute arm length w (θ) in the equations (1) and (2) is set with respect to the involute angle θ. A scroll compressor with a function that increases while changing in a sinusoidal or cosine wave shape with π [rad] as one cycle.

The scroll compressor according to claim 1, wherein the extension arm length w (θ) is given by the formula (3).
Here, α and β are coefficients, and N is a natural number of 1 or more.

The scroll compressor according to claim 1, wherein the extension arm length w (θ) is given by the equation (4).
Here, α and β are coefficients, and N is a natural number of 1 or more.

The scroll compressor according to claim 1, wherein the extension arm length w (θ) is given by the equation (5).
Here, α and β are coefficients, and N is a natural number of 1 or more.

The scroll compressor according to claim 1, wherein the extension arm length w (θ) is given by the formula (6).
Here, α and β are coefficients, and N is a natural number of 1 or more.

The scroll compressor according to any one of claims 2 to 5, wherein the coefficient β is 0 or more. When the curves defined by the equation (1) and the equation (2) are the outer curves, the inner curves of the fixed spiral body and the swinging spiral body each have the outer curve of the base circle. An outer envelope of a group of circles having a center on a curve rotated by π [rad] with respect to the center and having a radius equal to the swing radius of the swing scroll.
When the curves defined by the equations (1) and (2) are the inner curves, the outer curves of the fixed spiral body and the swinging spiral body each have the inner curve of the base circle. Any one of claims 1 to 6, wherein the inner wrapping line of a circle group having a center on a curve rotated by π [rad] with respect to the center and having a radius equal to the swing radius of the swing scroll. The scroll compressor described in. The scroll compressor according to any one of claims 1 to 7, wherein the rocking base plate has a flat outer shape.

Images