JP2004011659A - Thrust bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thrust bearing device capable of increasing its load capacity without increasing its size. <P>SOLUTION: A driving plate 5 as a driving part and a turning member 2 are connected to each other in a power transmissible manner via a supporting column 3 at the outside of a first roller 11 and a second roller 9 in the radial direction to the axis of a driving shaft 4, and so a roller can be arranged even in a center region of the turning member 2. To cope with further greater thrust load, when provided, the number of the rollers 9, 11 can be increased, namely, rollers can be properly arranged between the rollers, as shown in Fig.2, without enlarging the outer diameter of the turning member 2 and a casing 6. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a thrust bearing device capable of supporting a member that performs an eccentric rotational motion receiving a thrust force, and is preferably used in, for example, a scroll compressor and the like, and is suitable for supporting a turning member such as a scroll member that receives a thrust force. It concerns the device.
[0002]
[Prior art]
The scroll compressor performs a compression operation by providing a spiral partition in each of a revolving member and a fixed member, and changing the volume of a compression chamber formed between the two partitions with the rotation of the revolving member. Such scroll compressors are a kind of rotary compressors, are small in size, have no valve mechanism, and have continuous fluid compression, and exhibit less torque fluctuation, vibration, and noise than conventional reciprocating compressors. In recent years, practical use has been actively promoted because of its small number and high-speed operation.
[0003]
By the way, the turning member in the scroll compressor turns at the turning radius E without rotating. Therefore, a support mechanism that can support the specific movement of the turning member is required. On the other hand, as shown in Japanese Patent Application No. 2001-184900, an intermediate wheel is provided between a fixed member and a turning member, and a roller raceway surface on the fixed member side and a roller raceway surface on the turning member side of the intermediate wheel. A thrust bearing device has been developed in which eccentricity is made according to the eccentricity of the turning member with respect to the fixed member.
[0004]
According to such a thrust bearing device, the thrust force generated between the fixed member and the turning member is arranged between the fixed member and the intermediate wheel, and between the intermediate wheel and the turning member. In the roller, it can be received in line contact with each other, thereby reducing the amount of wear even under high load during high-speed turning, and also effective against rolling fatigue due to reduced surface pressure, thrust Long life of the bearing device can be achieved. Further, by eccentricizing the raceway surface on the fixed member side and the raceway surface on the turning member side of the intermediate wheel in accordance with the eccentricity of the turning member with respect to the fixed member, the behavior of rollers other than rotation is suppressed, and roller wear is reduced. Can be further suppressed. In addition, the intermediate wheel rotates at the same speed as the speed of the rotating shaft, the peripheral speed of the roller increases, and an oil film is easily secured, so that the life can be extended with respect to wear.
[0005]
[Problems to be solved by the invention]
By the way, in such a conventional thrust bearing device, in order to allow the eccentric movement of the turning member, on the raceway surface of the intermediate wheel on the fixed member side, each axis is concentrated at one point on the axis of the fixed member. A plurality of rollers are arranged side by side in the circumferential direction. On the other hand, on the raceway surface of the intermediate wheel on the side of the turning member, the plurality of rollers are arranged so that each axis is concentrated at one point on the axis of the turning member. Are arranged side by side. However, in order to increase the load capacity of the thrust bearing device, it is necessary to increase the diameter or the number of rollers. However, an increase in the roller diameter causes an increase in the axial length of the thrust bearing device, which is preferable. Absent. Also, an increase in the number of rollers is not preferable because it causes an increase in the outer diameter of the raceway surface of the intermediate wheel, that is, an increase in the outer diameter of the thrust bearing device.
[0006]
To cope with such a problem, Japanese Patent Application Laid-Open No. 2001-73968 discloses a scroll using a bearing device in which a plurality of rollers are provided in each of a plurality of stages with their axes parallel to each other, and the directions of the axes of the rollers are different for each stage. A compressor is disclosed. Such a bearing device is characterized in that the number of rollers can be changed relatively freely. However, since the rotating shaft is directly connected to the central portion of the orbiting scroll member, the rollers at any stage cannot be arranged at the center. Therefore, even if the area of the orbiting scroll member is large, the area where the rollers can be arranged is limited. Since it is limited only to the outside, there is a problem that the configuration of the scroll compressor is correspondingly increased.
[0007]
The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a thrust bearing device capable of increasing a load capacity without increasing the size.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a thrust bearing device of the present invention
A fixing member,
A turning member that performs eccentric rotational movement with respect to the fixed member,
A drive unit that receives power from the drive shaft,
A part of a fixed member extending to between the turning member and the driving unit, and an intermediate wheel disposed between the turning member and
A plurality of first rollers disposed between a part of the fixing member and the intermediate wheel;
A plurality of second rollers disposed between the intermediate wheel and the turning member,
The drive unit and the turning member are connected to each other in a radial direction with respect to the axis of the drive shaft outside at least one of the first and second rollers so as to transmit power. It is characterized by the following.
[0009]
[Action]
The thrust bearing device according to the present invention includes a fixed member, a turning member that performs eccentric rotational movement with respect to the fixed member, a driving unit that receives power from a drive shaft, and extends between the turning member and the driving unit. A part of the fixed member to be fixed, an intermediate wheel disposed between the turning member, a plurality of first rollers disposed between the part of the fixed member and the intermediate wheel, and the intermediate wheel And a plurality of second rollers disposed between the rotating member and the rotating member, wherein the driving unit and the rotating member are configured such that the first roller and the rotating member are arranged in a radial direction with respect to an axis of the drive shaft. Since at least one of the second rollers is connected so as to transmit power outside at least one of the rollers, unlike the related art, the rollers can be arranged in the central region of the turning member. Without expanding the outer shape of the first roller, etc. It is possible to increase the number of the second rollers, can correspond to increased load capacity.
[0010]
Further, the first rollers are arranged between the fixing member and the intermediate wheel so as to extend their respective axes in parallel, and the second rollers are arranged between the intermediate wheel and the turning member. Between the first roller and the second roller when the axes of the first roller and the second roller intersect with each other. Rolling the rollers in different directions is preferable because the turning member can be turned with respect to the fixed member via the intermediate wheel. In addition, “the axes extend in parallel” is sufficient if the axes extend substantially in parallel, and “the axes intersect” is sufficient if the axes substantially intersect, This means that some non-parallel or non-intersecting states due to roller dance and assembly errors are not considered.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view of a scroll compressor including a thrust bearing device according to the present embodiment. FIG. 2 is a view of the configuration of FIG. 1 viewed in the direction of the arrow cut along the line II-II.
[0012]
In FIG. 1, a substantially disc-shaped turning member 2 faces a substantially disc-shaped fixed plate 1 disposed in a cylindrical housing (which may be formed of a plurality of members) 6 whose upper and lower sides are closed. . A spiral partition 1a protruding from the opposing surface of the fixed plate 1 extends toward the turning member 2 and is in contact with the opposing surface. On the other hand, a spiral partition 2a protruding from the opposing surface of the revolving member 2 also extends toward the fixed plate 1 and is in contact with the opposing surface. Therefore, the compression chamber 7 which is a spiral passage is formed by the partition walls 1a and 2a. The compression chamber 7 communicates with a passage 1b formed inside the fixed plate 1 at the center of the scroll compressor, and is capable of pumping a fluid to the outside through the passage 1b.
[0013]
In the vicinity of the outer periphery of the revolving member 2, the upper ends in FIG. 1 of a plurality of (for example, four) columns 3 are connected. The support column 3 extends to the outside via an opening 6 a formed in the housing 6, and has a lower end connected to the vicinity of the outer periphery of the drive plate 5 arranged in parallel with the turning member 2. The drive plate 5 which is relatively movable with respect to the housing 6 is provided with a boss 5b having an opening 5a on the lower surface in FIG. The end of the drive shaft 4 is inserted into the opening 5a via a bearing 7 such as a radial needle bearing, for example, so that the turning member 2 is connected to the drive shaft 4 via the drive plate 5 and the support 3. It is supported so that it can move (turn) in the same phase.
[0014]
An intermediate wheel 8 is arranged below the turning member 2, between which a plurality of rollers 9 are rotatable in the same direction while being held by a retainer 10 with their axes parallel to each other. . Below the intermediate wheel 8, a bottom wall 6b of the housing 6 is arranged, between which a plurality of rollers 11 are rotatable in the same direction while being held by a retainer 12 with their axes parallel to each other. It has become. The axis Q of the fixed plate 1 is shifted by a distance E with respect to the axis P of the turning member 2 and the driving plate 5. In the present embodiment, the axis of the second roller 9 is orthogonal to the axis of the first roller 11. The number and arrangement of the rollers 9 and 11 are not limited as long as the axes are parallel.
[0015]
In the present embodiment, the fixed member formed by the fixed plate 1 and the housing 6, the turning member 2, the second roller 9, the intermediate wheel 8, the first roller 11, and the driving unit A certain drive plate 5 constitutes a thrust bearing device. The bottom wall 6b of the housing 6 corresponds to a part of the fixing member extending between the turning member 2 and the driving plate 5.
[0016]
Next, the operation of the thrust bearing device according to the present embodiment will be described. The turning member 2 driven by the driving shaft 4 via the driving plate 5 and the support 3 makes a turning motion around the axis Q with a turning radius E. Thereby, the partition wall 2a peristes, and the fluid inside the compression chamber 7 can be pushed out.
[0017]
Here, as shown in FIG. 2, when the turning member 2 makes a turning motion with respect to the housing 6 at a turning radius E, the intermediate wheel 8 moves in the rolling direction of the rollers 9 with respect to the turning member 2 by a distance A If the intermediate wheel 8 is further displaced relative to the housing 6 by a distance B in the rolling direction of the roller 11, then E = √ (A ² + B ² ). That is, since the axis of the second roller 9 and the axis of the first roller 11 are orthogonal to each other, by changing the values of A and B, E can be kept constant. This makes it possible to make a turning motion.
[0018]
Therefore, the orbiting member 2 can perform the orbiting motion while always maintaining a constant eccentric relationship with respect to the fixed plate 1, whereby a smooth compression operation of the scroll compressor is performed. A large thrust load acts on the turning member 2 due to the compressed gas pressure, and this thrust load is supported via the rollers 9 and 11 and the intermediate wheel 8.
[0019]
According to the present embodiment, the driving plate 5 and the revolving member 2 that are the driving units are arranged outside the rollers of the first roller 11 and the second roller 9 in the radial direction with respect to the axis of the driving shaft 4. Since the power can be transmitted through the support 3, the rollers can be arranged in the central region of the turning member 2. Therefore, when a larger thrust load is applied, the number of the rollers 9 and 11 increases. (In FIG. 2, the rollers may be appropriately arranged between the rollers.) This makes it possible to cope with the outer diameter of the turning member 2 and the housing 6 without increasing the outer diameter. On the other hand, when the applied thrust load is lower, By reducing the number of rollers 9 and 11, it is possible to flexibly cope with the specifications, for example, to further reduce the frictional resistance.
[0020]
As described above, the present invention has been described with reference to the embodiments. However, the present invention should not be construed as being limited to the embodiments, and it is needless to say that modifications and improvements can be made as appropriate. For example, rollers 9, 11 stacked in two stages are arranged between the turning member 2 and the bottom wall 6b of the housing 6, but three or more stages of rollers may be arranged. Further, the axes of the rollers 9 and 11 are not limited to being orthogonal, and it is sufficient that they intersect at 45 degrees or other angles. The material of the retainers 10 and 12 may be resin or metal.
[0021]
【The invention's effect】
The thrust bearing device according to the present invention includes a fixed member, a turning member that performs eccentric rotational movement with respect to the fixed member, a driving unit that receives power from a drive shaft, and extends between the turning member and the driving unit. A part of the fixing member to be fixed, an intermediate wheel disposed between the turning member, a plurality of first rollers disposed between the part of the fixing member and the intermediate wheel, and the intermediate wheel And a plurality of second rollers disposed between the rotating member and the rotating member, wherein the driving unit and the rotating member are configured such that the first roller and the rotating member are arranged in a radial direction with respect to an axis of the drive shaft. Since at least one of the second rollers is connected so as to transmit power outside at least one of the rollers, unlike the related art, the rollers can be arranged in the central region of the turning member. Without expanding the outer shape of the first roller, etc. It is possible to increase the number of the second rollers, can correspond to increased load capacity.
[Brief description of the drawings]
FIG. 1 is a sectional view of a scroll compressor including a thrust bearing device according to an embodiment.
FIG. 2 is a view of the configuration of FIG. 1 viewed in the direction of the arrow cut along the line II-II.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fixed member 2 Revolving member 4 Drive shaft 5 Drive plate 6 Housing 7 Compression chamber 8 Intermediate wheels 9, 11 Rollers 10, 12 Cage

Claims (2)

A fixing member,
A turning member that performs eccentric rotational movement with respect to the fixed member,
A drive unit that receives power from the drive shaft,
A part of a fixed member extending to between the turning member and the driving unit, and an intermediate wheel disposed between the turning member and
A plurality of first rollers disposed between a part of the fixing member and the intermediate wheel;
A plurality of second rollers disposed between the intermediate wheel and the turning member,
The drive unit and the turning member are connected to each other in a radial direction with respect to the axis of the drive shaft outside at least one of the first and second rollers so as to transmit power. A thrust bearing device characterized by the above-mentioned. The first rollers are arranged between the fixing member and the intermediate wheel so that their axes extend in parallel with each other,
The second roller is disposed between the intermediate wheel and the turning member so that their axes extend in parallel with each other,
The thrust bearing device according to claim 1, wherein the axis of the first roller and the axis of the second roller intersect.

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