JP2009228521A - Scroll type fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll type fluid machine in which galling or noise at a main shaft bearing and an auxiliary shaft bearing is reduced, while durability of the auxiliary shaft bearing and a rotating shaft is enhanced. <P>SOLUTION: A scroll type fluid machine (1) includes: an auxiliary shaft holder (44) for press-fitting an auxiliary shaft bearing (42); an auxiliary shaft frame (46) for supporting the auxiliary shaft holder at a shell (4) via a fixing member (48); and a buffer element (56) for permitting a prescribed inclination of the auxiliary shaft supported by the auxiliary shaft bearing with respect to a shaft center direction of the auxiliary shaft at the outer circumference thereof, which is not in contact with an auxiliary shaft (40). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a scroll type fluid machine, and more particularly, to a scroll type fluid machine suitable for being incorporated in a refrigeration air conditioner or a heat pump type water heater.

This type of scroll type fluid machine houses in a shell an electric motor and a scroll unit that is driven by the electric motor and compresses and discharges refrigerant sucked from outside, and connects the scroll unit and the electric motor. There is known a hermetic scroll compressor that rotatably supports a main bearing on the scroll unit side and a secondary bearing on the electric motor side.
A compressor that supports the secondary bearing via an elastic body (see, for example, Patent Document 1), a secondary bearing holder for fixing the secondary bearing, and a secondary shaft that supports the secondary bearing holder on the shell via a screw member 2. Description of the Related Art A compressor manufacturing method (see, for example, Patent Document 2) that includes a frame and assembles a sub-bearing holder or a sub-shaft frame in an inclined manner in accordance with the inclination of the sub-shaft with respect to the axial direction is known.

In the prior art described above, even if the rotation of the rotary shaft is caused by the operation of the scroll unit and the secondary shaft is inclined with respect to the axial direction, the rotational contact of the rotary shaft with respect to the main bearing and the secondary bearing is prevented. Wear and noise of the main bearing and the sub-bearing due to contact can be suppressed.
Japanese Patent No. 3766174 Japanese Patent No. 3,876,670

However, in the above-described prior art, the sub-bearing cannot be press-fitted and fixed between the sub-bearing holder or the sub-shaft frame and the rotating shaft.
In addition, since the radial load due to the inclination of the counter shaft is applied to the sub bearing and the sub shaft, the sub bearing and the sub shaft are damaged and worn, which reduces the life of the sub bearing and the rotating shaft. However, there is a problem that the relative durability of these is also lowered.

  The present invention has been made in view of such problems, and provides a scroll type fluid machine capable of suppressing wear and noise of the main bearing and the sub bearing while improving the durability of the sub bearing and the rotating shaft. The purpose is to do.

  In order to achieve the above object, a scroll type fluid machine according to claim 1 accommodates a drive unit and a scroll unit which is driven by the drive unit and discharges working fluid sucked from outside in a shell. A scroll type fluid machine that rotatably supports a rotary shaft connecting the unit and the drive unit by a main bearing on the scroll unit side and a sub bearing on the drive unit side, and a sub-bearing holder for press-fitting the sub-bearing; A counter-shaft frame that supports the sub-bearing holder on the shell via a fixing member, and a predetermined inclination with respect to the axial direction of the sub-shaft supported by the sub-bearing on the outer peripheral side that is not in contact with the sub-bearing It is characterized by having a permissible buffer member.

The invention according to claim 2 is characterized in that, in claim 1, the buffer member is provided on a contact surface of the fixing member with the auxiliary bearing holder.
Further, the invention according to claim 3 is characterized in that, in claim 1 or 2, a plurality of buffer members are provided together with the fixing member.
Furthermore, in the invention described in claim 4, in claim 3, the buffer member includes an inner cylindrical portion into which the fixing member is inserted and an outer cylindrical portion in which the buffer member is filled between the inner cylindrical portions. A bush member is formed.

The invention according to claim 5 is characterized in that, in claim 3, the sub-bearing holder has a buffer portion in which a cylindrical portion into which the fixing member is inserted is bonded to the sub-bearing holder via the buffer member.
Furthermore, in the invention of claim 6, in any one of claims 2 to 5, the fixing member is a screw member, and the buffer member is provided so as to surround the screw portion of the screw member, and the head portion of the screw member and A predetermined gap that allows a predetermined inclination between the head portion and the fastening surface in a non-contact manner is provided between the fastening surface on the side where the head portion is fastened.

Furthermore, the invention according to claim 7 is characterized in that, in claim 6, the buffer member is also provided in a predetermined gap.
The invention according to claim 8 is characterized in that, in claim 1, the buffer member is provided in an annular shape so as to surround the rotation shaft on the inner peripheral side from the fixing member of the auxiliary bearing holder.
Further, the invention according to claim 9 is characterized in that, in claim 1, the buffer member is provided in an annular shape so as to surround the rotation shaft on the outer peripheral side from the fixing member of the auxiliary bearing holder.

  Therefore, according to the scroll type fluid machine of the first aspect of the present invention, even if the rotation of the rotary shaft is caused by the operation of the scroll unit and the secondary shaft is inclined with respect to the axial direction, this inclination is compensated for by the secondary bearing. By providing a buffer member that allows non-contact with the outer peripheral side, it is possible to prevent uneven contact of the rotating shaft with respect to the main bearing and the sub-bearing. Wear and noise can be suppressed.

  In addition, since the buffer member is provided on the outer peripheral side that is not in contact with the sub-bearing, the sub-bearing can be press-fitted and fixed between the sub-bearing holder and the rotating shaft. In addition, it is possible to prevent damage and wear of the secondary bearing and the secondary shaft by allowing the secondary shaft to be tilted. Relative durability can also be improved.

According to the second aspect of the present invention, the buffer member is provided on the contact surface of the fixing member with the sub-bearing holder, thereby reliably preventing the fixing member from contacting the sub-bearing holder and tilting the sub-shaft. Can be smoothly allowed.
Furthermore, according to the invention described in claim 3, by providing a plurality of buffer members together with the fixing member, the radial load caused by the deflection deformation generated on the rotating shaft by the operation of the scroll unit is distributed and received at a plurality of locations. Therefore, it is preferable that the inclination of the secondary shaft can be allowed smoothly.

Furthermore, according to the invention described in claim 4, the buffer member forms a bush member comprising an inner cylinder into which the fixing member is inserted and an outer cylinder between which the buffer member is filled. Therefore, it is preferable that the inclination of the auxiliary shaft can be allowed with a simple configuration in which the bush member is simply fitted into the perforation of the auxiliary bearing holder.
According to the fifth aspect of the present invention, the auxiliary bearing holder has the buffer portion in which the cylindrical portion into which the fixing member is inserted is bonded to the auxiliary bearing holder via the buffer member, thereby assembling the scroll type fluid machine. The step of installing the buffer member at the stage can be omitted, and the inclination of the counter shaft can be allowed with a simple configuration, which is preferable.

  According to the invention of claim 6, the fixing member is a screw member, and the buffer member is provided so as to surround the screw portion of the screw member, and the head portion of the screw member and the side on which the head portion is fastened. By having a predetermined gap that allows the head portion and the fastening surface to be in non-contact with each other, the contact of the fixing member to the secondary bearing holder is reliably prevented. It is preferable because the inclination of the secondary shaft can be allowed smoothly.

Furthermore, according to the seventh aspect of the present invention, it is preferable that the buffer member is also provided in the predetermined gap, so that the contact of the fixing member with the sub-bearing holder can be more reliably prevented.
According to the inventions of claims 8 and 9, the buffer member is provided in an annular shape so as to surround the rotation shaft on the inner peripheral side or the outer peripheral side from the fixing member of the sub-bearing holder. It is preferable that the tilting of the countershaft can be allowed smoothly as in the case where the buffer member is provided in the subbearing or in contact with the subbearing while improving the durability of the rotating shaft.

Hereinafter, embodiments of the present invention will be described from the first embodiment with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a hermetic scroll compressor as an example of a scroll type fluid machine according to the present embodiment. The compressor 1 is incorporated in a refrigeration circuit such as a refrigeration air conditioner or a heat pump type hot water heater. It is. The circuit includes a path through which a carbon dioxide refrigerant (hereinafter referred to as a refrigerant), which is an example of a working fluid, circulates. The compressor 1 sucks the refrigerant from the path, compresses the refrigerant, and discharges the refrigerant toward the path.

  The compressor 1 includes a shell 2, and a center shell 4 that forms a cylindrical body of the shell 2 is hermetically fitted with an upper side and a lower side by a top shell 6 and a bottom shell 8, respectively, and the inside of the center shell 4 is hermetically sealed. The discharge pressure of the refrigerant is acting. The center shell 4 is connected to a suction pipe 10 for sucking the refrigerant taken in from the circuit, and a discharge pipe 12 for sending the compressed refrigerant in the shell 2 to the circuit is connected to an appropriate position of the top shell 6. .

In the center shell 4, a scroll unit 14, an electric motor 16, and a pump unit 18 are accommodated in this order from above, and a rotating shaft 20 is disposed in the electric motor 16, and the rotating shaft 20 is energized by energization of the electric motor 16. Driven.
The scroll unit 14 includes a movable scroll 22 and a fixed scroll 24, and the scrolls 22 and 24 cooperate with each other and suck a refrigerant from the suction pipe 10 to form a compression chamber. The volume of the compression chamber is reduced while moving toward the center of the scroll unit 14 by the revolving orbiting motion of the movable scroll 22 with respect to the fixed scroll 24.

On the other hand, the electric motor 16 includes a cylindrical stator 26 and a rotor 28 disposed inside the stator 26, and the rotor 28 has a predetermined gap from the stator 26 and the rotating shaft 20. It is rotated together.
The rotor 28 is formed by laminating silicon steel plates or the like, which are magnetic materials, on the outer peripheral surface thereof, and permanent magnets having magnetic poles adjacent to each other in opposite polarities are embedded therein. On the other hand, the stator 26 is wound with a stator winding that generates a magnetic field that acts on the permanent magnet of the rotor 28 when the electric motor 16 is energized.

On the other hand, the pump unit 18 constitutes a gear pump such as a trochoid, and the oil supply formed by sucking the lubricating oil in the oil storage chamber 30 formed inside the bottom shell 8 and perforating the rotary shaft 20 in the axial direction. The path 32 is raised and supplied from the upper end of the rotary shaft 20 to the scroll unit 14 and the bearing.
Specifically, the rotary shaft 20 is rotatably supported by a main shaft frame 38 provided between the scroll unit 14 and the electric motor 16 via a main bearing 36 with a main shaft 34 on the upper end side thereof, that is, the scroll unit 14 side. And is connected to the scroll unit 14.

  On the other hand, the rotary shaft 20 is connected to the electric motor 16 and the pump unit via the auxiliary shaft 40 on the lower end side thereof, that is, the electric motor 16 side, through the auxiliary bearing 42 and the auxiliary bearing holder 44 for fixing the auxiliary bearing 42. 18 is rotatably supported by a countershaft frame 46 provided between the pump unit 18 and the pump unit 18, and the pump unit 18 is connected to the electric motor 16 and the rotary shaft 20. 14 and drive.

  According to the compressor 1 described above, the orbiting scroll 22 revolves without rotating as the rotary shaft 20 rotates, so that the refrigerant sucked into the scroll unit 14 via the suction pipe 10 passes through the compression chamber. The compression chamber is compressed while being moved toward the center of the scroll unit 14, and then discharged into the shell 2, circulated through the shell 2, and then sent out of the compressor 1 through the discharge pipe 12.

Incidentally, the secondary bearing 42 is a so-called sliding bearing that is press-fitted and fixed between the rotary shaft 20 and the secondary bearing holder 44, and the secondary bearing holder 44 is fixed to the secondary shaft frame 46 via a screw member 48, The shaft frame 46 is shrink-fitted or press-fitted and fixed inside the center shell 4.
Specifically, as shown in the assembly perspective view when the secondary bearing holder 44 of FIG. 2 is fastened by the screw member 48 from the lower side of the secondary shaft frame 46, the secondary bearing holder 44 has four perforations 50 having a diameter D1. The countershaft frame 44 is formed with four holes 52 having a diameter D2 (D2 <D1), and a welding nut 54 is welded to the upper surface of the countershaft frame 44 at a position matching the hole 52 in advance. It is fixed.

The secondary bearing holder 44 is mounted with the secondary bearing holder 44 in a state where the perforation 50 and the perforation 52 are aligned with each other from the lower side of the secondary shaft frame 46, and further, the threaded portion of the screw member 48 from the lower side of the secondary bearing holder 44. 48a is fixed to the countershaft frame 46 by being screwed and fastened to the welding nut 54.
Here, the screw member 48 is fastened to the welding nut 54 via a cylindrical elastic member 56 that can be inserted into each perforation 50, and the elastic member 56 is formed of rubber, a resin material, or the like.

Specifically, as shown in the cross-sectional view of the main part of FIG. 3, the elastic member 56 has a height H that is substantially the same as the plate thickness t of the sub-bearing holder 44 and an outer shape that is substantially the same as or smaller than the diameter D1 of the bore 50. It is formed to have Do and an inner diameter Di into which the screw portion 48a can be inserted, and is provided so as to surround the screw portion 48a.
The inner diameter Di is set in advance so that the elastic member 56 is supported with a predetermined fit without the elastic member 56 dropping off or shifting due to the insertion of the threaded portion 48a into the elastic member 56.

Further, the head portion 48b of the screw member 48 and the fastening surface 44a, which is the lower surface of the auxiliary bearing holder 44, to which the head portion 48b is fastened, allow a predetermined inclination of the auxiliary shaft 40 with respect to the axial center direction of the rotary shaft 20. Are spaced apart with a predetermined gap G.
As described above, in this embodiment, even when the rotary shaft 20 is flexibly deformed by the thrust load due to the operation of the scroll unit 14 and the sub shaft 40 is inclined with respect to the axial direction, this inclination is applied to the sub bearing 42. By providing the elastic member 56 that is allowed on the outer peripheral side that is non-contact, it is possible to prevent uneven contact of the rotary shaft 20 with respect to the main bearing 36 and the sub-bearing 42, and thus the main bearing 36 resulting from this uneven contact. In addition, wear and noise of the secondary bearing 42 can be suppressed.

  Moreover, since the elastic member 56 is provided on the outer peripheral side that is not in contact with the sub-bearing 42, the sub-bearing 42 can be press-fitted and fixed between the sub-bearing holder 44 and the rotary shaft 20. It is possible to prevent the drop-off and the accompanying uneven contact, and furthermore, it is possible to prevent damage and wear of the sub-bearing 42 and the sub-shaft 40 by allowing the inclination of the sub-shaft 40. It is also possible to prevent the life of the shaft 20 from being reduced and to improve the relative durability of these.

Further, since the elastic member 56 is provided on the contact surface of the screw member 48 with the auxiliary bearing holder 44, the contact of the screw member 48 with the auxiliary bearing holder 44 can be reliably prevented.
Specifically, the elastic member 56 is provided so as to surround the screw portion 48a of the screw member 48, and the head portion 48b of the screw member 48 and the fastening surface 44a of the auxiliary bearing holder 44 on the side to which the head portion 48b is fastened. By having a gap G between which the head portion 48b and the fastening surface 44a are not in contact with each other, the contact of the screw member 48 with the sub-bearing holder 44 can be reliably prevented.

Furthermore, since a plurality of elastic members 56 are provided together with the screw members 48, radial loads resulting from the deflection deformation generated in the rotary shaft 20 can be distributed and received at a plurality of locations. Can be smoothly allowed.
Next, a second embodiment will be described with reference to a perspective view shown in FIG.
In the second embodiment, the elastic member 56 includes a bush member 62 including an inner cylindrical portion 58 in which the screw member 48 is inserted, and an outer cylindrical portion 60 in which the elastic member 56 is filled between the inner cylindrical portion 58. The other components have the same configuration as that of the first embodiment. In this case, the auxiliary shaft can be simply configured by fitting the bushing member 62 into the bore 50 of the auxiliary bearing holder 44. A tilt of 40 can be tolerated, which is preferable. Note that the outer cylindrical portion 60 may be welded and fixed to the perforation 50 in order to prevent the bushing member 62 from falling off or slipping.

Next, a third embodiment will be described with reference to a perspective view of the auxiliary bearing holder 44 shown in FIG.
In the fifth embodiment, an elastic portion 66 is formed on the sub-bearing holder 44 by bonding the cylindrical portion 64 into which the screw member 48 is inserted to the sub-bearing holder 44 via the elastic member 56. In this case, the step of installing the elastic member 56 at the assembly stage of the compressor 1 can be omitted, and the inclination of the countershaft 40 is allowed with a simple configuration. This is preferable.

Next, a fourth embodiment will be described with reference to a cross-sectional view of the main part shown in FIG.
In the sixth embodiment, the elastic member 56 is also extended to the gap G, and the other configuration is the same as that of the first embodiment. In this case, the screw for the sub-bearing holder 44 is used. It is preferable because the contact of the member 48 can be more reliably prevented. The same effect can be obtained by similarly expanding the elastic member 56 to the gap G in the bush member 62 of the second embodiment and the elastic portion 66 of the third embodiment.

Next, the fifth embodiment will be described with reference to the cross-sectional views of the relevant parts shown in FIGS.
In the fifth embodiment, instead of providing a plurality of elastic members 56 so as to surround each screw member 48, the elastic member 56 is provided on the inner peripheral side (FIG. 7) or the outer peripheral side of the screw member 48 of the auxiliary bearing holder 44. (FIG. 8) are provided with ring-shaped elastic rings 68 and 70 so as to surround the rotary shaft 20, respectively, and the other configurations are the same as those in the first embodiment. It is possible to smoothly allow the inclination of the auxiliary shaft 40 as if the elastic member 56 is provided inside the auxiliary bearing 42 or in contact with the auxiliary bearing 42 while improving the durability of the bearing 44 and the rotary shaft 20. This is preferable. When the screw member 48 is fastened, the counter shaft 40 is fastened with a gap G that allows the head portion 48b and the fastening surface 44a to be in non-contact with each other, or the elastic member 56 is placed in the gap G. Providing it in an expanded manner is preferable because it is possible to reliably prevent uneven contact in the screw member 48 when the inclination of the sub shaft 40 is allowed by the elastic rings 68 and 70.

The description of one embodiment of the present invention is finished above, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the hermetic scroll compressor 1 using a carbon dioxide refrigerant incorporated in a refrigeration circuit such as a refrigeration air conditioner or a heat pump type hot water heater has been described. The present invention can be applied to fluid machines such as compressors and expanders in various fields using the above working fluids.

1 is a longitudinal sectional view showing a hermetic scroll compressor according to a first embodiment of the present invention. It is an assembly perspective view of the sub-bearing holder of FIG. It is sectional drawing which expanded and showed the principal part of FIG. It is the perspective view which expanded and showed the bush member which concerns on 2nd Embodiment of this invention. It is the perspective view which expanded and showed the elastic part formed in the subbearing holder which concerns on 3rd Embodiment of this invention. It is sectional drawing which expanded and showed the elastic member of the sealed scroll compressor which concerns on 4th Embodiment of this invention. It is a principal part longitudinal cross-sectional view of the hermetic scroll compressor which concerns on 5th Embodiment of this invention. It is a principal part longitudinal cross-sectional view of the hermetic scroll compressor which concerns on the modification of 5th Embodiment of this invention.

Explanation of symbols

1 Scroll compressor (scroll type fluid machine)
4 Center shell (shell)
14 Scroll unit 16 Electric motor (drive unit)
20 Rotating shaft 36 Main bearing 42 Sub bearing 44 Sub bearing holder 44a Fastening surface 46 Sub shaft frame 48 Screw member (fixing member)
48a Screw portion 48b Head portion 56 Elastic member (buffer member)
58 Inner cylindrical part 60 Outer cylindrical part 62 Bush member 64 Cylindrical part 66 Elastic part (buffer part)
68 Elastic ring (buffer member)
70 Elastic ring (buffer member)

Claims (9)

A drive unit and a scroll unit that is driven by the drive unit and discharges the working fluid sucked from the outside are accommodated in the shell, and the rotary shaft that connects the scroll unit and the drive unit is the main shaft on the scroll unit side. A scroll type fluid machine rotatably supported by a receiver and a sub-bearing on the drive unit side,
A sub-bearing holder for press-fitting and fixing the sub-bearing;
A countershaft frame for supporting the subbearing holder on the shell via a fixing member,
A scroll type fluid machine comprising: a buffer member that allows a predetermined inclination with respect to an axial direction of a sub shaft supported by the sub bearing on an outer peripheral side that is not in contact with the sub bearing.   The scroll type fluid machine according to claim 1, wherein the buffer member is provided on a contact surface of the fixing member with the auxiliary bearing holder.   The scroll type fluid machine according to claim 1, wherein a plurality of the buffer members are provided together with the fixing member.   The said buffer member forms the bush member which consists of an inner cylinder part in which the said fixing member is inserted, and an outer cylinder part with which the said buffer member is filled between this inner cylinder part. 4. A scroll type fluid machine according to 3.   The scroll-type fluid machine according to claim 3, wherein the sub-bearing holder has a buffer portion in which a cylindrical portion into which the fixing member is inserted is bonded to the sub-bearing holder via the buffer member. The fixing member is a screw member, and the buffer member is provided so as to surround a screw portion of the screw member,
A predetermined gap is provided between the head portion of the screw member and a fastening surface on the side to which the head portion is fastened to allow the predetermined inclination to be in a non-contact state between the head portion and the fastening surface. A scroll type fluid machine according to any one of claims 2 to 5.   The scroll type fluid machine according to claim 6, wherein the buffer member is also provided in the predetermined gap.   2. The scroll fluid machine according to claim 1, wherein the buffer member is provided in an annular shape so as to surround the rotating shaft on an inner peripheral side of the fixing member of the auxiliary bearing holder.   2. The scroll type fluid machine according to claim 1, wherein the buffer member is provided in an annular shape so as to surround the rotating shaft on an outer peripheral side of the fixing member of the auxiliary bearing holder.

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