JP2002213373A - Scroll type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll type compressor that has high strength of a spiral wall of a scroll member, is easily machined, and does not reduce compressing efficiency. SOLUTION: A central leading part 101 has a constitution where a part from a point β1 to a point β'1 and a part from a point β2 to a point β'2 have a constant thickness, these parts of the central leading part 101 are stepless parts M1 and M2 fitting to each other, and a part from the point β'1 to the point β'2 is a step part U having a step shape part D in at least its part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor provided in an air conditioner, a refrigeration system, and the like.

[0002]

2. Description of the Related Art A scroll compressor has a fixed scroll member and an orbiting scroll member (a pair of scroll members).
By arranging the spiral wall bodies in combination with each other, and by orbiting the orbiting scroll member with respect to the fixed scroll member, the volume of the compression chamber formed between the wall bodies is gradually reduced, The fluid in the compression chamber is compressed. FIG. 6 is a perspective view of a scroll member provided in a conventional scroll compressor of this type. FIG. 7 is a plan view of a central portion of a spiral wall described in Japanese Patent Application Laid-Open No. S59-58187, which is also a conventional scroll member. FIG. 8 is a plan view of the center of a spiral wall described in Japanese Patent Application Laid-Open No. 9-68177, which is also a conventional scroll member. FIG. 9 is a plan view of a central portion of a spiral wall described in Japanese Patent Application Laid-Open No. 10-68392 as a conventional scroll member.

As shown in FIGS. 6A and 6B, the pair of scroll members are a fixed scroll member 1 having a spiral wall 1b provided on an end plate 1a, and a spiral wall 2b provided on an end plate 2a.
Is configured in combination with the orbiting scroll member 2 provided with. The two scroll walls 1b, 2b are engaged with each other at an angle of 180 degrees from each other, and the orbiting scroll member 2 is caused to revolve.
The fluid is compressed by reducing the volume while moving the sealed space formed between b from the outside to the inside.

At this time, the innermost enclosed space has a high pressure,
Since the pressure in the closed space outside of this is lower than the high pressure, the reaction force of the compressed gas repeatedly acts on the central portions of the spiral walls 1b and 2b each time the orbiting scroll member 2 revolves. Becomes Further, since the central portions of the spiral walls 1b, 2b are the starting ends of the spiral walls 1b, 2b, rigidity tends to be insufficient. In particular, the end plates 1a, 2a of the scroll member integrally formed and the spiral wall are formed. There was a case where the vicinity of the roots of 1b and 2b was broken by fatigue. Means for solving such a problem is disclosed in JP-A-59-58187. This will be described with reference to FIG.

As shown in FIG. 1, according to the disclosed technology, the position of an arbitrary expansion angle α degrees on the involute curve forming the outer wall of the spiral wall 3 of the scroll member, and the position of the involute curve forming the inner wall on the involute curve 3 Is connected by two large and small circular arcs, and the involute curve and the circular arc form the center start end of the spiral wall. Thereby, the wall thickness of the center start end of the spiral wall 3 could be increased, and the strength could be improved. However, according to the technique disclosed herein, there is still a problem that high stress concentration is still observed in the vicinity of the small arc on the tip end side of the central portion of the spiral wall 3, and the rigidity is not sufficiently improved.

FIG. 8 shows a technique disclosed in Japanese Patent Application Laid-Open No. 9-68177 to further improve the rigidity. In the disclosed technique, for each of the fixed and orbiting scroll members, the position of an arbitrary expansion angle α on the involute curve forming the outer wall of the spiral wall 4 and the expansion angle position of α + 180 degrees on the involute curve forming the inner wall. Is formed so as to have a stepped cross section. Further, the shape of the central portion of the spiral wall 6 in each stage is such that the innermost closed space volume formed by combining the spiral ventilated closed space and the spiral back sealed space in the meshing state of the two scroll members is substantially zero. And the stepped spiral wall is made thinner toward the upper step away from the end plate. Since the step portion is provided at the center of the spiral wall as described above, it is possible to increase only the wall thickness of the root portion at the center of the spiral wall, which is particularly problematic in the strength, and it is possible to further improve the strength.

[0007] Further, Japanese Patent Application Laid-Open No. 10-68392 shown in FIG.
In the technology disclosed in the publication, the central portion of the spiral wall 5 of the scroll member is stepped, and a spiral curve and a connection point of an arc connecting to the spiral curve are formed in a range from the inner inner wall to the outer wall.
A shape having a root fillet 5a is provided.
A gap is provided in the wall thickness direction to avoid interference with the root fillet (not shown) of the spiral wall 6 on the other side. For this reason, it is possible to reduce the concentration of the stress at the root of the spiral wall and improve the strength.

[0008]

However, according to the prior art described in Japanese Patent Laid-Open No. 9-68177 described above, there are the following problems. That is, in the closed space formed by the scroll wall of the fixed scroll member and the orbiting scroll member of the scroll type compressor, the dead volume in the final compression step is two volumes whose innermost closed space is located outside by one turn. The volume of the innermost enclosed space at the moment of communicating with the crescent-shaped enclosed space (seal-off point). If the dead volume defined as described above is large, the high-pressure gas re-expands and the compression efficiency increases. Will be reduced.

Here, the seal-off point is substantially at the moment when the spiral wall surfaces of the pair of scroll members, which have been in contact with each other in the compression step, are separated from each other, or when the spiral outer wall is located near the center of the end plate. Determined at the moment it takes to port. Usually, the discharge port of a scroll compressor is
It is installed on the end plate of the fixed scroll member, and at a position where there is no problem with the strength of the spiral wall of the fixed scroll member,
In addition, it is installed near the ventral side of the center of the spiral wall so that the seal-off point comes as close as possible to the final stage of the compression process. For this reason, in order to reduce the dead volume in order to improve the performance of the compressor, when the spiral wall of the orbiting scroll member is fixed to the vicinity of the moment when the spiral wall is applied to the discharge port installed near the center of the end plate of the fixed scroll member. It is necessary to seal the innermost air gap as much as possible by meshing between a pair of spiral wall surfaces of the orbiting scroll member.

By the way, the above-mentioned Japanese Patent Application Laid-Open No. 9-6817.
In the prior art described in Japanese Patent Application Laid-Open No. 7-107, the central portion of the spiral wall is stepped in order to improve the strength. However, when an attempt is made to seal the innermost closed space, the meshing portion in the step height direction is required. The number of places to be newly sealed increases. When a portion to be sealed is slid and sealed, the size of the scroll member to be managed during machining is increased, and the cost is increased. In addition, when the seal is incomplete, there is a problem that the gas leaks from the innermost enclosed space and the compression efficiency is reduced.

The above-mentioned Japanese Patent Application Laid-Open No. H10-68392 has been described.
In the prior art described in Japanese Patent Application Laid-Open Publication No. H11-27139, at a seal-off point determined by a discharge port, a portion where a pair of spiral wall surfaces of a fixed and orbiting scroll member mesh with each other is a spiral wall portion formed by an involute curve. Sealing between them is possible, and the above problem does not occur. However, as described above, the discharge port is arranged so that the seal-off point comes as close as possible to the final stage of the compression process. The portion where the pair of spiral wall meshes often appears inside the spiral wall formed by the involute curve, in which case the number of meshing portions in the step height direction also needs to be newly sealed. I do. When a portion to be sealed is slid and sealed, the size of the scroll member to be managed during machining is increased, and the cost is increased. In addition, when the seal is incomplete, there is a problem that the gas leaks from the innermost enclosed space and the compression efficiency is reduced.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a scroll type compressor in which the strength of a scroll wall of a scroll member is high, processing is easy, and compression efficiency is not reduced. I do.

[0013]

The present invention employs the following means in order to solve the above-mentioned problems. That is, the scroll type compressor according to the first aspect has a scroll wall provided upright on one side surface of the end plate, and a fixed scroll member fixed at a fixed position and an upright wall provided on one side surface of the other end plate. And a revolving scroll member supported to be capable of revolving revolving motion while being prevented from rotating by engaging the respective revolving walls, and having a wall thickness at the center start end of each of the revolving walls. In the scroll compressor in which a step-shaped portion that gradually increases in thickness toward the base side of each of the end plates is formed, a start point of the outer wall involute at each central start end is a point β1, and a start point of the inner wall involute is β2. When the points and the seal-off points are β′1 point and β′2 point, the central start ends are between the β1 point and the β′1 point and between the β2 point and the β′2 point. To the height direction of each spiral wall It has a constant wall thickness dimension, and is a stepless portion between the central starting end is engaged with each other, the beta '
A portion between one point and the β′2 point is a stepped portion having the stepped portion in at least a part thereof.

According to the first aspect of the present invention, when the orbiting scroll member revolves orbits with respect to the fixed scroll member, (1) the stepless portion communicates with the discharge port. It is important to keep the inner compression chamber airtight, between the meshing points β1 and β′1 between the spiral walls, and from the point β2 to β ′.
Since the step portion is not formed between the two spiral walls, the two spiral walls can be engaged with each other so that gas leakage hardly occurs and airtightness can be maintained as compared with the case where the step is provided in this portion. Become like Further, since the stepless portion is not required to be processed in the stepless portion, a processing step requiring processing accuracy can be omitted, so that the processing can be facilitated. (2) Since the stepped portion forms a stepped portion from the point β′1 to the point β′2 at which the meshing between the two spiral walls meshed with the stepless portion is released, the innermost step is formed. In order to keep the compression chamber airtight, there is no need to seal between the walls of the spiral walls. Thus, the strength of each spiral wall can be increased by forming a stepped portion in a stepped portion that does not require the sealing property and providing a thick portion. Also,
As described above, the stepped portion in the meshing between the two spiral walls does not affect the airtightness of the innermost compression chamber communicating with the discharge port, so that the compression efficiency is not reduced.
This eliminates the need to perform high-precision processing in consideration of hermeticity when processing the stepped portion, and can facilitate the processing.

According to a second aspect of the present invention, there is provided the scroll type compressor according to the first aspect, wherein the stepless portion has a first curve from the β1 point to the β′1 point, and a point from the β2 point. The β′2 point is formed by a second curve, the stepped portion has a two-step shape having a thickness at the base side of the end plate, and the lower side near the base side has a third curve and a fourth step. The upper curve side is formed by a fifth curve and a sixth curve, and the first to sixth curves are the first curve, the third curve, the fourth curve, and the second curve when the respective spiral walls are viewed in opposition. The curve and the first curve, the fifth curve, the sixth curve, and the second curve each form one continuous curve.

According to the scroll compressor of the second aspect, the same operation as that of the first aspect can be obtained. That is, when the orbiting scroll member revolves orbits with respect to the fixed scroll member, (1) the stepless portion consisting of the first curve and the second curve forms the innermost compression chamber of the innermost compression chamber communicating with the discharge port. Since this is an important part for maintaining airtightness, the wall thickness in the height direction of the spiral wall is constant so that no stepped portion is formed. As a result, compared to the case where the first curve and the second curve are provided with steps, the two spiral walls can be engaged with each other so that gas leakage hardly occurs and airtightness can be maintained. Further, since the stepped portion is not required to be formed in the first curve and the second curve, a processing step requiring high processing accuracy can be omitted, and the processing can be facilitated. (2) Since the stepped portion formed by the third to sixth curves is formed at a portion where the meshing between the two spiral walls meshed at the stepless portion is released, the innermost compression chamber is formed. There is no need to seal between the walls of the spiral walls to maintain airtightness.
Thus, the strength of each spiral wall can be increased by making the portions of the third to sixth curves, which do not require the sealing property, have a two-step thickness. Further, as described above, in the engagement between the two spiral walls, the stepped portion having the two-step shape consisting of the third curve to the sixth curve has an airtightness of the innermost compression chamber communicating with the discharge port. Since there is no influence, the compression efficiency is not reduced. Accordingly, when processing the two-step portion composed of the third to sixth curves, it is not necessary to perform high-precision processing in consideration of airtightness, and the processing can be facilitated.

According to a third aspect of the present invention, there is provided the scroll type compressor according to the first or second aspect, wherein the β′1 point and the β′2 point are located between the spiral walls. A first compression chamber communicating with a discharge port of the member, and a second compression chamber adjacent to an outer peripheral end of the first compression chamber are formed, and immediately before the second compression chamber communicates with the discharge port. It is characterized in that it substantially coincides with the meshing point between the spiral walls in a meshing state.

According to the third aspect of the present invention, the scroll walls can be easily engaged with each other up to the seal-off point determined by the position of the discharge port. The volume of the closed space can be easily reduced to the minimum volume.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention has a spiral scroll wall provided on one side of an end plate, and a fixed scroll member fixed at a fixed position and a vertical wall provided on one side of another end plate. A revolving scroll member having another spiral wall, the revolving scroll member being supported to be capable of revolving revolving while being prevented from rotating by engaging the respective spiral walls, and a wall thickness of a central start end of the spiral wall being The present invention relates to a scroll-type compressor in which a step-shaped portion that becomes stepwise thicker toward the base of each end plate is formed, and an embodiment of the compressor will be described below with reference to the drawings. Of course, the invention is not limited to this.

FIG. 1 is a sectional view showing the overall structure of the scroll compressor according to the present embodiment. Also, FIG.
It is a figure which shows the components used for the scroll type compressor, (a) is a perspective view of a fixed scroll member, (b) is a perspective view of an orbiting scroll member. FIG. 3 (a)
FIG. 3 is a perspective view of a center portion of a start end of a spiral wall on the fixed scroll member side, and FIG. 2 (b) is a diagram showing an engaged state of the fixed scroll member and the orbiting scroll member;
It is sectional drawing which looked at the fixed scroll member side from the cross section perpendicular | vertical to the axis of a discharge port. FIG. 4 is an enlarged front view of the central portion of the start end of the spiral wall on the fixed scroll member side. FIG. 5 is an explanatory view showing an example of a method of forming a center start end of a spiral wall included in a scroll member of the scroll compressor.

The scroll-type compressor of the present invention is particularly characterized in that the scroll member (the fixed scroll member and the orbiting scroll member) has a center start end shape of the spiral wall. After a description of the configuration, a detailed description of the center start end will be given.

In FIG. 1, reference numeral 11 denotes a housing. The housing 11 comprises a housing main body 11a formed in a cup shape and a lid plate 11b fixed to the opening end side of the housing main body 11a. Have been.
A scroll-type compression mechanism including a fixed scroll member 12 and an orbiting scroll member 13 is provided inside the housing 11. As shown in FIG. 2A, the fixed scroll member 12 has a spiral wall 1 on one side surface of the end plate 12a.
2b is erected. Further, as shown in FIG. 2B, the orbiting scroll member 13 has an end plate 13a.
A spiral wall 13b is provided upright on one side surface, and the spiral wall 13b has substantially the same shape as the spiral wall 12b on the fixed scroll member 12 side. Further, as shown in FIG. 1, tip seals 27 and 28 for increasing the airtightness of the compression chamber C are disposed on the upper edges of the spiral walls 12b and 13b.

As shown in FIG. 1, the fixed scroll member 1
2 is fastened to the housing main body 11a by bolts 14. The orbiting scroll member 13 is eccentric with respect to the fixed scroll member 12 by the orbital revolving radius, and is shifted in phase by 180 °.
2b and 13b are engaged with each other, and are supported so as to be able to revolve and rotate while being prevented from rotating by a rotation preventing mechanism 15 provided between the lid plate 11b and the end plate 13a.

A rotating shaft 16 having a crank 16a is penetrated through the cover plate 11b, and bearings 17a, 17
b, it is rotatably supported by the lid plate 11b. A boss 18 is provided at the center of the other end surface of the end plate 13a on the orbiting scroll member 13 side. Crank 1 on boss 18
The eccentric portion 16b of 6a is rotatably accommodated via a bearing 19 and a drive bush 20, and the orbiting scroll member 13 revolves orbitally by rotating the rotating shaft 16. Further, a balance weight 21 for canceling an unbalance amount given to the orbiting scroll member 13 is attached to the rotating shaft 16.

Further, inside the housing 11, a suction chamber 22 is formed around the fixed scroll member 12, and a discharge cavity 23 defined by a bottom surface inside the housing body 11a and another side surface of the end plate 12a is formed. Have been. The housing main body 11a is provided with a suction port 24 for guiding a low-pressure fluid toward the suction chamber 22, and the center of the end plate 12a on the fixed scroll member 12 side moves to the center while gradually reducing the volume. Discharge port 2 for guiding high-pressure fluid from compression chamber C toward discharge cavity 23
5 are provided. The other side surface (back surface) of the end plate 12a is provided with a discharge valve 26 that opens the discharge port 25 only when a pressure greater than a predetermined level acts.

The overall operation of the scroll compressor having the above-described configuration according to the present embodiment will be described. The rotary shaft 16 is driven to rotate about its axis by a motor (not shown). Then, the eccentric shaft 16b causes the orbiting scroll member 13 to revolve and revolve with respect to the fixed scroll member 12 while being prevented from rotating. Then, the low-pressure fluid taken in from the suction port 24 moves while gradually reducing the volume and gradually increasing the pressure, and is finally discharged to the discharge cavity 23 through the discharge port 25.

The overall structure and operation of the scroll compressor according to the present embodiment have been described above. Next, the shape of the central start end, which is a feature of the present invention, will be described with reference to FIGS.
The details will be described below with reference to FIG. In the following description, the scroll wall 12b on the fixed scroll member 12 side
The description will be continued with reference to the center start end 101 of the spiral scroll wall 13b of the orbiting scroll member 13 in the present embodiment.
And the same shape.

As shown in FIG. 3 (a), the central starting end portion 101 is formed with a step-shaped portion D in which the wall thickness is increased in two steps toward the base of the end plate 12a. Configuration. That is, in this step-shaped portion D,
The wall thickness changes in the height direction (the direction perpendicular to the end plate 12a) of the spiral wall 12b, and the wall thickness is thicker at the base side, which is the end plate 12a side, and thinner above it. Have been. This is the same as the conventional case. Note that reference numeral 25 shown in the figure is the discharge port.

One of the characteristic points of the central starting end 101 is as follows.
As shown in FIG. 3 (b), a state in which the spiral wall 12 b of the fixed scroll 12 and the spiral wall 13 b of the orbiting scroll 13 mesh with each other to form a compression chamber, and is communicated with the discharge port 25. (Hereinafter referred to as the first compression chamber C)
1. The upstream compression chamber located next to the second compression chamber C2
(Referred to as “seal”) in order to maintain a constant thickness in the height direction and the step-shaped portion D disposed outside this range. That is, as shown in FIG.
The outer wall involute start point of the center start end 101 is β1
Assuming that the point, the inner wall involute start point is β2 point, and the seal-off points are β′1 point and β′2 point, the central starting end 101 is between β1 point and β′1 point and between β2 point and β′1 point. Stepless portions M1, which have a constant thickness dimension in the height direction of the spiral wall 12b between two points, and mesh with each other with another central start end (not shown). M
The portion between the point β′1 and the point β′2 is a stepped portion U having the stepped portion D.

The outer wall involute start point (β1 point)
And, the inner wall involute start point (point β2) is a start point of forming an involute curve that forms the shape of the spiral wall 12b around the involute base circle 110.
In addition, the seal-off point (β′1 point and β′2 point)
Is the contact point at the moment when the spiral walls 12b, 13b of the fixed scroll member 12 and the orbiting scroll member 13 contacted in the compression step are separated from each other, or the meshing at the moment when the second compression chamber C2 looks into the discharge port 25. Is a point.

The stepless portion M1 is, as shown in FIG.
The stepless portion M2 is formed by a first curve 121 extending from the β1 point to the β′1 point, and the stepless portion M2 is formed by a β ′ from the β2 point.
It is formed by a second curve 131 extending to two points. On the other hand, the stepped portion U has a two-stage shape having a thickness at the base side of the end plate 12a, and the lower side near the base side is the third stage.
Curve 122 and fourth curve 132, the upper side is fifth curve 12
3 and the sixth curve 133. When the spiral wall 12b is viewed from the opposite side as shown in FIG. 5, the first curve 121 to the sixth curve 133 are the first curve 121, the third curve 122, the fourth curve 132, and the second curve 13
1 and the first curve 121, the fifth curve 123, the sixth curve 133, and the second curve 131 each form one continuous curve.

The first curves 121 to 121 of the center starting end 101
An example of a method for generating the sixth curve 133 will be described below with reference to FIG. First, the outer wall 120 of the spiral wall 12b composed of an involute curve from the point β1, which is the intersection point of the extension line G at the extension angle α1 of the involute base circle 110 with the radius R0 and the outer involute curve, in the direction of the larger extension angle. Has been created. Further, the above β which is the intersection of the inflation line H and the ventral involute curve at the inflation angle α1 + 180 degrees of the involute base circle 110
From the two points, the inner wall 130 of the spiral wall 12b having an involute curve is created in the direction of increasing the extension angle.

The first curve 121 extending inward from the point β1 is an arc having a radius R1, and the second curve 131 extending inward from the point β2 is an arc having a radius R2. The first curve 121 and the second curve 131 can be obtained by the equation of R1 + R = R2, where R is the orbital radius of the orbiting scroll member 13. Then, the center of the first curve 121 is set to O
1, the center of the second curve 131 is O2, and the first curve 121
The β′1 point is set so that the angle formed by β1−O1−β′1 becomes a predetermined α ′, and the first curve 121 forms a spiral wall surface between β1−β′1. Further, β′2 points are set on the second curve 131 so that the angle formed by β2-O2-β′2 becomes a predetermined α ′, and the second curve 131 forms a spiral wall surface between β2 and β′2. .

Next, a stepped wall surface is formed between β′1 and β′2, and the lower wall thickness is made larger than the upper wall thickness to form the stepped portion D. Step shaped part D
Orbiting scroll member 1 with respect to fixed scroll member 12
The following auxiliary lines are set in order to create a wall curve that meshes with each stage when 3 is engaged. That is, a straight line L1 connecting the O1 point and the β′1 point, the O2 point and the β ′
A straight line L2 connecting the two points is set. Here, the straight lines L1 and L2 are parallel to each other. A straight line connecting the O1 point and the O2 point is defined as L0. Also, β′1 parallel to the straight line L0
A straight line Lt is set so as to be separated by δ in the direction of the point. In addition, a straight line Lu that is parallel to the straight line L0 and separated by δ in the direction of the β′2 point is set. The intersections of the straight line L1 and the straight line Lu, the straight line L1 and the straight line Lt, the straight line L2 and the straight line Lu, and the straight line L2 and the straight line Lt are respectively defined as U1,
Let T1, U2, T2.

A method for creating a lower curve by using the auxiliary line will be described below. A third curve 122 extending inward from the point β′1 has a radius R1 + δ centered on the point U1.
Is an arc. The fourth that extends inward from the β'2 point
The curve 132 is an arc having a radius R2-δ centered on the point U2. The fourth curve 132 is smoothly connected to the third curve 122 at a point U3 on the straight line Lu. Next, a method of creating the upper curve will be described. A fifth curve 123 extending inward from the point β′1 is an arc having a radius R1−δ around the point T1. A sixth curve 133 extending inward from the point β′2 has a radius R around the point T2.
This is an arc of 2 + δ. This sixth curve 133 is
The curve 123 is smoothly connected to a point T3 on the straight line Lt.

The shape of the spiral wall 12b created by the above method has a constant wall thickness in the height direction in the range created by the first curve 121 and the second curve 131, and furthermore, the third curve 122
And the lower wall surface composed of the fourth curve 132 and the fifth curve 1
In a range created by the upper wall surface composed of 23 and the sixth curve 133, the wall thickness changes stepwise in the height direction.
The switching position of the wall thickness in the height direction is determined by the spiral wall 12.
The height is substantially the center of the height b. By the way, in a state where both scroll members are assembled, the gap between the two switching positions of these step-shaped portions D is 0.05 to 1 mm.
It is desirable to set the degree to such a degree that the confinement of the compressed gas can be prevented.

Here, a method of setting α ′ for setting the β′1 point and β′2 point will be described. The first compression chamber C1 communicating with the discharge port 25 of the fixed scroll member 12 and the second compression chamber C2 adjacent to the outer peripheral end of the first compression chamber C1 are formed between the spiral walls 12b and 13b. In the meshing state immediately before the second compression chamber C2 communicates with the discharge port 25 (immediately before the second compression chamber C2 looks into the discharge port 25), the β′1 point and β′2 point are the same. As shown in the drawing, if the point of engagement between the center start end 101 of the fixed scroll member 12 and the center start end 201 of the orbiting scroll member 13 at this time is V1 and V2, β′1 determined from α ′ It is desirable that the point and the β′2 point substantially coincide with the meshing points V1 and V2. However, even if they do not exactly match,
The points β′1 and β′2 may be set so as to be located outside the points V1 and V2 (in the direction in which the extension angle increases).

Next, the shift amount δ for setting the straight line Lt and the straight line Lu will be described. This shift amount δ
Of the central start end portion 101, the lower wall surface (the wall surface formed by the third curve 122 and the fourth curve 132) and the upper wall surface (the fifth curve 123) in which the wall thickness changes stepwise in a stepwise manner. In order to suitably adjust the difference in wall thickness between the first and second curves 133 and 133, it is desirable to set the shift amount δ from the viewpoint of strength. Generally, the scroll member is generally processed by an end mill. From the viewpoint of productivity, it is preferable to process the scroll member with an end mill having a diameter as large as possible from the viewpoint of improving the accuracy and the yield. For this reason, there is also a method of selecting based on the curvature of the fourth curve 132 which is the minimum R portion of the spiral wall 12b determined by the shift amount δ.

As shown in FIG. 4, fillets 140 are provided at the roots of the central start ends 101 and 201 of the fixed scroll member 12 and the orbiting scroll member 13 to alleviate the concentration of the response. This fillet 1
The reference numeral 40 is installed in the vicinity of the range from the point β1 to the point β′2. In the present embodiment, the fixed member 40 has a corner R shape of about R1 and is formed integrally with the orbiting scroll members 12, 13. . As a method of creating the fillet 140, the end mill having a desired fillet shape formed on the outer periphery of the end face of an end mill (not shown) is processed, and in another step, the end surface outer periphery is formed using another end mill having a shape close to a right angle. Remove unnecessary parts. Usually, high machining accuracy is required for machining the scroll member, so that the final shape is finished by two or more end milling operations. Therefore, fillet 140
End milling for removal is usually performed at the same time as finishing of the spiral wall, and does not lead to an increase in the number of processing steps.

In order to prevent the fillet 140 from interfering with the other scroll member, a chamfer (not shown) is provided on the upper end surface of each of the spiral walls 12b and 13b. Here, the fillet 140 is formed only on the wall surface between the β1 and β′2 points, and since the processing tolerance is increased by processing with an end mill different from the other wall surfaces, the fillet 140 is designed at this portion. It is desirable to set a very small gap. By limiting the installation range of the fillet 140 in this manner, the wall surface between β′2 and β2 can be processed by a cutter that forms the final shape, and the processing accuracy of the wall surface is improved.

In this embodiment, the first curve 121 to the sixth curve 133 between β1 and β2 are smoothly connected by an arc. However, the present invention is not limited to this. To connect smoothly using an elliptical arc,
Alternatively, of course, a configuration in which a straight line is combined with an arc or an elliptical arc to smoothly connect them can also be adopted. Further, in the present embodiment, the curves forming the spiral walls 12b and 13b are configured by involute curves. However, the involute curves may be configured by mathematically corrected curves, or may have properties similar to involute curves. It is good also as what is comprised by the curve which has. In any case, since the present invention relates to the inside of those curves, the configuration is naturally possible. Further, in the present embodiment, the center start end of the spiral wall 13b on the orbiting scroll member 13 side is formed in the same shape as the center start end 101 of the spiral wall 12b on the fixed scroll member 12 side. In the case where each central start end is formed in a different shape with the fixed scroll member 12, the interval between the point β1 and the point β′1 and the interval between the point β2 and the point β′2 are different from each other. It has a constant thickness dimension in the height direction of the spiral wall, and between these central start ends is a stepless portion that meshes with each other, and at least between the β′1 point and the β′2 point, Naturally, it is also possible to configure so as to be a stepped part having the stepped part in a part.

The effects of the scroll compressor of the present embodiment described above are summarized below. The scroll compressor according to the present embodiment includes a central start end 101 and a central start end 101 of the fixed scroll member 12 and the orbiting scroll member 13 that mesh with each other.
01, which is the involute start point on the outer wall side
Regarding the wall surface shape between one point and the β2 point which is the involute start point on the inner wall side, the height direction between the β1 point and the β′1 point and between the β2 point and the β′2 point is the height direction. And a stepless portion M1 or M2 in which the center start portions 101 and 201 mesh with each other during the revolving motion of the orbiting scroll member 12, and a portion from the point β′1 to the point β′2 A configuration in which the step is a stepped portion U having a stepped portion D is adopted.

In the scroll member of this scroll compressor, the spiral wall between the two points β′1-β ′ is set stepwise in the height direction, so that a gas reaction force acts upon gas compression. Even in such a case, it is possible to increase the wall thickness of the root portion of each of the center leading ends 101 and 201, which is strict in strength, and to ensure a sufficient strength.

That is, when the orbiting scroll member 13 makes a revolving orbiting motion with respect to the fixed scroll member 12, each spiral wall is important for maintaining the airtightness of the first compression chamber C1 communicating with the discharge port 25. Between β1 point and β′1 meshing between 12b and 13b and from β2 point to β′2
By forming the stepless portions M1 and M2 without steps between the points, the two spiral walls 12 are formed so that gas leakage hardly occurs and airtightness can be maintained as compared with the case where steps are provided in these portions.
b and 13b can be engaged with each other. Moreover,
Since the stepless portions M1 and M2 do not have to be machined, a machining process requiring machining accuracy can be omitted, so that the machining can be facilitated.

On the other hand, when the orbiting scroll member 13 makes a revolving orbiting motion with respect to the fixed scroll member 12, the stepped portion U is formed between the point β′1 which is the seal-off point and the point β′2. By increasing the thickness at this portion, the strength of each of the spiral walls 12b and 13b can be increased.
In addition, the stepped portion D formed in the stepped portion U does not affect the airtightness of the first compression chamber C1 communicating with the discharge port 25, so that the compression efficiency is not reduced (in other words, each step is not affected). Since the spiral walls 12b and 13b can be easily engaged with each other, the innermost first compression chamber C
(1) The volume of the closed space can be easily reduced, so that the dead volume can be reduced and the compression efficiency can be increased.) This eliminates the need to perform high-precision processing in consideration of airtightness when processing the step portion D, and can facilitate the processing. As described above, according to the present embodiment, both scroll members 12, 1
It is possible to provide a scroll compressor in which the strength of each of the spiral walls 12b and 13b is high, the processing is easy, and the compression efficiency is not reduced.

In this embodiment, the spiral walls 12b, 1
The generation range of the portion where the wall thickness of 3b is constant in the height direction and the generation range of the portion where the wall thickness differs in the height direction can be appropriately selected by using the variable α ′. The difference between the upper and lower wall thicknesses of U can be appropriately selected based on the shift amount δ that is a variable. For example, the shift amount δ
Is large, it is possible to increase the substantial small arc radius of the center start ends 101 and 201, and it is possible to improve the strength. Also, by taking the shift amount δ small, the minimum R of the fourth curve 132 increases,
The diameter of the end mill used in processing the scroll member can be increased, and the output in processing the scroll member can be improved. Thus, the degree of freedom in designing the shape of the spiral wall can be increased by setting the above variables.

In this embodiment, β′1 point and β′2
A configuration is adopted in which the point substantially coincides with the mesh points V1 and V2 between the spiral walls 12b and 13b in the mesh state immediately before the second compression chamber C2 communicates with the discharge port 25. According to this configuration, since the wall surfaces of the two spiral walls 12b and 13b can be easily engaged with each other up to the seal-off point determined by the discharge port 25, the first compression chamber C1
It is possible to easily reduce the enclosed space volume to the minimum volume, and consequently minimize the dead volume, increase the compression efficiency, and increase the strength of the center of the spiral wall. Becomes possible.

[0048]

According to the scroll type compressor according to the first aspect of the present invention, each center start end is set between the point β1 and the point β′1 and between the point β2 and the point β′2. But,
A stepped portion having a constant wall thickness and a stepless portion in which the central start ends are meshed with each other, and a portion between the β′1 point and the β′2 point has a stepped portion in at least a part thereof. The configuration was adopted as a part.

According to this structure, when the orbiting scroll member revolves orbits with respect to the fixed scroll member, it is important to keep the innermost compression chamber communicating with the discharge port airtight. Β'1 from the β1 point where the spiral wall meshes
By forming a stepless portion without a step between the point and the point from the point β2 to the point β′2, gas leakage hardly occurs and airtightness can be maintained as compared with a case where a step is provided in this part. Thus, the two spiral walls can be engaged with each other.
Further, since the stepped portion does not need to be processed in the stepless portion, a processing step requiring processing accuracy can be omitted, so that the processing can be facilitated.

On the other hand, when the orbiting scroll member makes a revolving orbiting motion with respect to the fixed scroll member, the stepped portion between the point β′1 and the point β′2, which is the seal-off point, is used as a stepped portion. And the strength of each spiral wall can be increased. In addition, since the step formed in the stepped portion does not affect the airtightness of the innermost compression chamber communicating with the discharge port, the compression efficiency does not decrease. This eliminates the need to perform high-precision processing in consideration of hermeticity when processing the stepped portion, and can facilitate the processing. As described above, according to the present invention, it is possible to provide a scroll compressor in which the strength of each spiral wall of both scroll members is high, which is easy to process, and which does not reduce the compression efficiency.

According to the second aspect of the present invention, the stepless portion is formed by the first curve and the second curve, and the stepped portion is formed by the lower stage formed by the third curve and the fourth curve. , A fifth curve and a sixth curve, an upper two-stage shape, and further, a first curve, a third curve, a fourth curve, and a second curve, and a first curve, a fifth curve, a sixth curve, and a fifth curve. The two curves were each configured to form one continuous curve.

According to this configuration, the same effect as the first aspect can be obtained. That is, when the orbiting scroll member revolves orbits with respect to the fixed scroll member, it is important to maintain the airtightness of the innermost compression chamber communicating with the discharge port. Curve and second
Since the curved portion is a stepless portion having no step, the two spiral walls can be engaged with each other so that gas leakage hardly occurs and airtightness can be maintained as compared with the case where the portion has a step. Further, since the stepless portion need not be machined in the stepless portion formed by the first curve and the second curve, the machining process requiring the machining accuracy can be omitted, so that the machining is facilitated. Can be.

On the other hand, when the orbiting scroll member makes a revolving orbiting motion with respect to the fixed scroll member, the portions of the third to sixth curves, which are the seal-off points, are set as stepped portions. By increasing the thickness, the strength of each spiral wall can be increased. Moreover, the two-stage shape composed of the third to sixth curves does not affect the airtightness of the innermost compression chamber communicating with the discharge port, so that the compression efficiency does not decrease. This eliminates the need to perform high-precision processing in consideration of hermeticity when processing the stepped portion, and can facilitate the processing. As described above, according to the present invention, the strength of each scroll wall of both scroll members is high,
In addition, it is possible to provide a scroll type compressor which is easy to process and does not reduce the compression efficiency.

According to the scroll type compressor of the third aspect, the β′1 point and the β′2 point are meshed between the spiral walls in the meshing state immediately before the second compression chamber communicates with the discharge port. A configuration that substantially matches the point was adopted. According to this configuration, since the wall surfaces of the two spiral walls can easily mesh with each other up to the seal-off point determined by the discharge port, the innermost closed space volume can be easily reduced to the minimum volume. As a result, it is possible to provide a scroll type compressor which minimizes the dead volume, has a high compression efficiency, and has a high strength at the center of the spiral wall.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of a scroll type compressor of the present invention, and is a cross-sectional view showing an entire configuration thereof.

FIG. 2 is a view showing parts used in the scroll compressor, wherein (a) is a perspective view of a fixed scroll member,
(B) is a perspective view of the orbiting scroll member.

3A and 3B are views showing a main part of the scroll type compressor, wherein FIG. 3A is a perspective view of a center start end of a spiral wall, and FIG. 3B is a view showing a state in which a fixed scroll member and an orbiting scroll member are engaged with each other. It is a figure which shows, and is the sectional view which looked at the fixed scroll member side from the section perpendicular to the axis of a discharge port.

FIG. 4 is a plan view of a center start end of a spiral wall of the fixed scroll member of the scroll compressor.

FIG. 5 is an explanatory view showing an example of a method of forming a central start end of a spiral wall of a scroll member of the scroll compressor.

6A and 6B are views showing a scroll member used in a conventional scroll compressor, wherein FIG. 6A is a perspective view of a fixed scroll member, and FIG. 6B is a perspective view of an orbiting scroll member.

FIG. 7 is a view showing another scroll member used in the conventional scroll compressor, and is a plan view of a central portion of a spiral wall.

FIG. 8 is a view showing another scroll member used in the conventional scroll compressor, and is a plan view of a central portion of a spiral wall.

FIG. 9 is a view showing another scroll member used in the conventional scroll compressor, and is a plan view of a central portion of a spiral wall.

[Explanation of symbols]

 Reference Signs List 12: fixed scroll member 12a, 13a: end plate 12b, 13b: spiral wall 13: orbiting scroll member 25: discharge port 101: center start end 121: first curve 131 ... second curve 122 ... third curve 132 ... fourth curve 123 ... fifth curve 133 ... sixth curve C1 ... first compression chamber C2 ... second compression Chamber D: Stepped portion M1, M2: Stepless portion U: Stepped portion

Continued on the front page (72) Inventor Mami Takeuchi 1 Nagoya Research Laboratories, Mitsubishi Heavy Industries, Ltd. Nagoya Laboratory, Iwazuka-cho, Nakamura-ku, Nagoya City, Aichi Prefecture Address Mitsubishi Heavy Industries, Ltd. Cooling Business Division F-term (reference) 3H029 AA02 AA16 AB03 BB31 BB44 CC03 CC05 3H039 AA02 AA12 BB05 BB07 CC02 CC03 CC04 CC06 CC07

Claims (3)

[Claims] 1. A fixed scroll member fixed at a fixed position and having a spiral wall provided upright on one side surface of an end plate, and another spiral wall provided upright on one side surface of another end plate. And a revolving scroll member supported so as to be able to revolve and revolve while preventing the rotation by engaging the spiral walls with each other, wherein the wall thickness of the central start end of each spiral wall is fixed to the end plate. In the scroll type compressor in which a step-shaped portion that gradually increases in thickness toward the side is formed, the outer wall involute start point of each of the center start ends is set to β1.
When the point, the inner wall involute start point is β2 point, and the seal-off point is β′1 point and β′2 point, each of the central start ends is between the β1 point and the β′1 point, β2
Between the point and the β′2 point has a constant thickness dimension in the height direction of each spiral wall, and these stepless central portions are meshed with each other as a stepless portion, and the β ′ A scroll compressor characterized in that a portion between one point and the β′2 point is a stepped portion having the stepped portion at least in a part thereof. 2. The scroll compressor according to claim 1, wherein the stepless portion has a first curve from the β1 point to the β′1 point and a second curve from the β2 point to the β′2 point. The stepped portion is formed in a two-step shape having a thickness on the base side of the end plate, and the lower side near the base side has the third and fourth curves, and the upper side has the fifth and fifth curves. And the first to sixth curves are the first curve, the third curve, the fourth curve, and the second curve, and the first curve and the second curve when the respective spiral walls are viewed in opposition. 5th curve, 6th curve and 2nd curve
The scroll type compressor, wherein each of the curves forms one continuous curve. 3. The scroll compressor according to claim 1, wherein the β′1 point and the β′2 point communicate with a discharge port of the fixed scroll member between the spiral walls. Each of the spirals in a meshing state in which a compression chamber and a second compression chamber adjacent to the outer peripheral end side of the first compression chamber are formed, and the second compression chamber is in a state immediately before communicating with the discharge port. A scroll compressor characterized by being substantially coincident with a mesh point between walls.