U.S. patent application number 11/724440 was filed with the patent office on 2007-09-27 for scroll fluid machine.
Invention is credited to Tamotsu Fujioka, Hidetoshi Ishikawa, Masaru Tsuchiya.
Application Number | 20070224072 11/724440 |
Document ID | / |
Family ID | 38229709 |
Filed Date | 2007-09-27 |
United States Patent
Application |
20070224072 |
Kind Code |
A1 |
Ishikawa; Hidetoshi ; et
al. |
September 27, 2007 |
Scroll fluid machine
Abstract
A scroll fluid machine comprises a fixed scroll and an orbiting
scroll that engages with the fixed scroll to form a compression
chamber between the fixed and orbiting scrolls. Near the outer
circumference of the fixed and/or orbiting scroll, an annular
dust-seal groove is provided. In the groove, a dust seal fits to
prevent a gas from coming into the compression chamber or from
leaking out of the compression chamber. In the dust-seal groove, an
annular holder or piece is provided to prevent heat from
transferring to the dust seal.
Inventors: |
Ishikawa; Hidetoshi;
(Yokohama-shi, JP) ; Fujioka; Tamotsu;
(Yokohama-shi, JP) ; Tsuchiya; Masaru;
(Yokohama-shi, JP) |
Correspondence
Address: |
JOEL D. SKINNER, JR.;SKINNER AND ASSOCIATES
212 COMMERCIAL ST.
HUDSON
WI
54016
US
|
Family ID: |
38229709 |
Appl. No.: |
11/724440 |
Filed: |
March 15, 2007 |
Current U.S.
Class: |
418/55.6 ;
418/55.1 |
Current CPC
Class: |
F04C 27/005 20130101;
F04C 29/04 20130101; F04C 18/0215 20130101 |
Class at
Publication: |
418/55.6 ;
418/55.1 |
International
Class: |
F01C 1/02 20060101
F01C001/02; F01C 1/063 20060101 F01C001/063 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 23, 2006 |
JP |
2006-80147 |
Claims
1. A scroll fluid machine comprising: a fixed scroll having a fixed
end plate; and an orbiting scroll having an orbiting end plate, a
dust-seal groove being formed close to an outer circumference of
the fixed and/or orbiting scroll, an annular holder that fits in
the dust-seal groove, the annular holder being made of material
having thermal conductivity lower than material of said scrolls and
having a groove in which a dust seal fits.
2. A scroll fluid machine of claim 1 wherein the annular holder is
cast together with the scroll when the scroll is cast.
3. A scroll fluid machine of claim 1 wherein the annular holder is
fixed in the dust-seal groove.
4. A scroll fluid machine of claim 1 wherein the annular holder is
pressingly fitted in the dust-seal groove.
5. A scroll fluid machine of claim 3 wherein the annular holder is
fitted in the dust-seal groove owing to difference in thermal
expansion rate.
6. A scroll fluid machine of claim 1 wherein the fixed and orbiting
scrolls are made of Al or Al alloy and the annular holder is made
of steel.
7. A scroll fluid machine of claim 1 wherein an unevenness is
formed axially on an outer circumferential surface of the annular
holder.
8. A scroll fluid machine of claim 1 wherein an unevenness is
formed circumferentially on an outer circumferential surface of the
annular holder.
9. A scroll fluid machine of claim 1 wherein a groove is radially
formed on an outer circumferential surface of the annular
holder.
10. A scroll fluid machine of claim 1 wherein a hole goes through a
bottom wall of the annular holder.
11. A scroll fluid machine of claim 1 wherein a side wall of the
annular holder becomes thicker towards a bottom.
12. A scroll fluid machine of claim 1 wherein a radial projection
is provided at a bottom of the annular holder.
13. A scroll fluid machine comprising: a fixed scroll having a
fixed end plate; and an orbiting scroll having an orbiting end
plate, a dust-seal groove being formed close to an outer
circumference of the fixed and/or orbiting scroll, an annular piece
being formed on an inner circumferential surface of the dust-seal
groove, the annular piece being made of metal having thermal
conductivity lower than material of said scrolls.
14. A scroll fluid machine of claim 13 wherein the annular piece is
formed by plating.
15. A scroll fluid machine of claim 13 wherein the annular piece is
formed by thermal spraying.
16. A scroll fluid machine of claim 13 wherein the annular piece
has unevenness.
17. A scroll fluid machine of claim 13 wherein the annular piece
becomes thicker gradually towards a bottom of the dust-seal groove.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a scroll fluid machine such
as a scroll compressor or a scroll vacuum pump.
[0002] In the specification, the front and rear mean an entrance
and bottom of a dust-seal groove.
[0003] JP6-207588A and JP3248618B2 disclose a scroll fluid machine
such as a scroll compressor or a scroll vacuum pump, comprising a
driving shaft having an eccentric axial portion; an orbiting scroll
comprising an orbiting end plate having an orbiting wrap; a fixed
scroll comprising a fixed end plate having a fixed wrap; and a
self-rotation-preventing device for preventing the orbiting scroll
from rotating on its own axis, the orbiting scroll being rotatably
mounted around the eccentric axial portion, the fixed wrap engaging
with the orbiting wrap to form a sealed chamber.
[0004] With the eccentric axial portion of the driving shaft and
the self-rotation-preventing device, the orbiting scroll is
eccentrically revolved so that the volume of the sealed chamber
reduces towards the center for compression of a gas or increases
away from the center for expansion.
[0005] The orbiting and fixed wraps comprise an involute-curve
which increases in diameter gradually in a direction of rotation; a
curve which comprises a plurality of short curves around the center
or a combination of the two curves. A radial gap between the fixed
and orbiting wraps is exactly defined not to contact the wraps to
each other or not to open excessively.
[0006] Engagement grooves are formed at the ends of the fixed and
orbiting wraps. A tip seal fits in the engagement groove to slide
on the end plate of the facing end plate airtightly.
[0007] A dust-seal groove is formed in the outer circumference of
the fixed or orbiting end plate and a dust seal fits in the
dust-seal groove.
[0008] The dust seal prevents air from coming into a lower-pressure
chamber in a vacuum pump or prevents a gas from leaking out of a
higher-pressure chamber in a scroll compressor.
[0009] The dust-seal groove in which the dust seal fits is formed
with the scroll when the fixed or orbiting scroll made of Al or
light alloy is molded, or is cut mechanically after molding of the
scroll.
[0010] Heat which is generated during operation around the driving
shaft of the scroll or frictional heat of the tip seal with the end
plate are transferred to the dust seal in the dust-seal groove of
the scroll to cause the dust seal to deteriorate or to wear
rapidly.
[0011] Air bubbles are inevitably generated in the fixed or
orbiting scroll that is cast. If the air bubbles are produced in
the side sealed by dust seal when the dust-seal groove is
mechanically formed, sealing capability will become poor to make
performance of the scroll fluid machine worse.
SUMMARY OF THE INVENTION
[0012] In view of the disadvantage in the prior art, it is an
object of the invention to provide a scroll fluid machine that
prevents transfer of heat generated around a driving shaft for a
fixed scroll or an orbiting scroll or frictional heat of a tip seal
with an end plate, to a dust seal thereby improving durability and
achieving stable performance for a long time.
[0013] It is another object of the invention to provide a scroll
fluid machine to prevent air bubbles exposing on the dust-seal
groove.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The features and advantages of the invention will become
more apparent from the following description with respect
embodiments as shown in accompanying drawings wherein:
[0015] FIG. 1 is a vertical sectional side view of a fixed scroll
in a scroll fluid machine;
[0016] FIG. 2 is an enlarged vertical sectional side view of the
first embodiment of a scroll fluid machine according to the present
invention;
[0017] FIG. 3 is an enlarged vertical sectional side view of the
second embodiment of a scroll fluid machine according to the
present invention;
[0018] FIG. 4 is an enlarged vertical sectional side view of the
third embodiment of a scroll fluid machine according to the present
invention;
[0019] FIG. 5 is an enlarged vertical sectional side view of the
fourth embodiment of a scroll fluid machine according to the
present invention;
[0020] FIG. 6 is an enlarged vertical sectional side view of the
fifth embodiment of a scroll fluid machine according to the present
invention;
[0021] FIG. 7 is an enlarged vertical sectional side view of the
sixth embodiment of a scroll fluid machine according to the present
invention;
[0022] FIG. 8 is an enlarged vertical sectional side view of the
seventh embodiment of a scroll fluid machine according to the
present invention;
[0023] FIG. 9 is an enlarged vertical sectional side view of the
eighth embodiment of a scroll fluid machine according to the
present invention;
[0024] FIG. 10 is an enlarged vertical sectional side view of the
ninth embodiment of a scroll fluid machine according to the present
invention;
[0025] FIG. 11 is an enlarged vertical sectional side view of the
tenth embodiment of a scroll fluid machine according to the present
invention;
[0026] FIG. 12 is an enlarged vertical sectional side view of the
eleventh embodiment of a scroll fluid machine according to the
present invention;
[0027] FIG. 13 is an enlarged vertical sectional side view of the
twelfth embodiment of a scroll fluid machine according to the
present invention; and
[0028] FIG. 14 is an enlarged vertical sectional side view of the
thirteenth embodiment of a scroll fluid machine according to the
present invention
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0029] FIG. 1 is a vertical sectional side view of a fixed scroll 1
of a scroll fluid machine.
[0030] The fixed scroll 20 has an involute-curve fixed wrap 23 on
the front surface of a fixed end plate 22 having a cooling fin 21
on the rear surface. A driving shaft passes through an axial hole
24 at the center of the fixed end plate 22 via a bearing.
[0031] A tip seal groove 25 is formed at the front end of the fixed
wrap 23 and a tip seal 26 fits in the tip seal groove 25.
[0032] A dust-seal groove 27 is formed in the fixed end plate 22
around the fixed wrap 23. A dust seal (not shown) fits in the
dust-seal groove 27.
[0033] The present invention relates to a scroll fluid machine in
which the dust-seal groove 27 is novel.
[0034] FIG. 2 shows an enlarged view of a dust-seal groove, which
will be described.
[0035] Near the outer circumference of a fixed end plate 1 made of
Al or its alloy, an annular holding groove 3 is formed around a
fixed wrap 2. In the holding groove 3, an annular holder 5 is
provided to have a dust-seal groove 4.
[0036] The annular holder 5 is made of steel having thermal
conductivity lower than material of the fixed scroll and is cast
together with the fixed end plate 1 when the fixed scroll is
cast.
[0037] The holding groove 3 may be formed by cutting off the fixed
end plate 1 of the cast fixed scroll, and the annular holder 3 is
then fixed in the holding groove 3.
[0038] The annular holder 5 may be pressingly fitted into the
holding groove mechanically, or may be fixed in the holding groove
3 by hot fitting or cold fitting.
[0039] In FIGS. 3-14, the same numerals are allotted to the same
members as those in FIG. 2 and description thereof is omitted.
[0040] FIG. 3 shows the second embodiment in which the annular
holder 5 has an unevenness 6 extending axially on the outer
circumferential surface.
[0041] FIG. 4 shows the third embodiment in which the annular
holder 5 has a circumferential unevenness 7 on the outer
circumferential surface.
[0042] FIG. 5 shows the fourth embodiment in which the annular
holder has a groove 8 radially in the outer circumferential
surface. A plurality of grooves 8 have bottoms.
[0043] FIG. 6 shows the fifth embodiment in which the annular
holder 5 has a through hole 9 radially of the fixed end plate
1.
[0044] FIG. 7 shows the sixth embodiment in which the annular
holder 5 has side walls becoming gradually thicker towards the
bottom of the holding groove 3.
[0045] FIG. 8 shows the seventh embodiment in which an annular
projection 10 is radially formed from the outer circumferential
surface of the annular holder 5.
[0046] FIG. 9 shows the eighth embodiment in which on an inner side
surface of the dust-seal groove 4 of the fixed end plate 1 of the
fixed scroll, an annular piece 11 made of metal having thermal
conductivity lower than the fixed end plate 1 is fixed. The annular
piece 11 may be pressingly fitted by a mechanical device or
attached on the lower-pressure side surface of the dust-seal groove
4 by casting.
[0047] FIG. 10 shows the ninth embodiment in which metal that has
thermal conductivity lower than the fixed end plate is attached on
the lower-pressure side surface of the dust-seal groove 4 by
plating or thermal spraying to form an annular pressure-receiving
surface 12.
[0048] FIG. 11 shows the tenth embodiment in which an unevenness 13
is formed on the inner circumferential surface of an annular piece
11 made of metal having thermal conductivity lower than the end
plate of the scroll.
[0049] FIG. 12 shows the eleventh embodiment in which the annular
piece 11 comprises a gradually-thicker portion 14 towards the
bottom of the dust-seal groove 4.
[0050] FIG. 13 shows the twelfth embodiment in which the annular
piece 11 has an inward projection 15.
[0051] FIG. 14 shows the thirteenth embodiment in which the annular
piece 11 has an outward projection 16 which forms a bottom wall of
the dust-seal groove 4.
[0052] The foregoing merely relate to embodiments of the invention.
Various changes and modifications may be made by a person skilled
in the art without departing from the scope of claims wherein:
* * * * *