U.S. patent application number 09/789202 was filed with the patent office on 2002-08-22 for easy-manufacture oldham coupling.
This patent application is currently assigned to Scroll Technologies. Invention is credited to Barito, Thomas R., Fenocchi, David M..
Application Number | 20020114721 09/789202 |
Document ID | / |
Family ID | 25146885 |
Filed Date | 2002-08-22 |
United States Patent
Application |
20020114721 |
Kind Code |
A1 |
Fenocchi, David M. ; et
al. |
August 22, 2002 |
EASY-MANUFACTURE OLDHAM COUPLING
Abstract
An improved Oldham coupling ring is relatively easy to
manufacture. Opposed circular arc portions are connected by angled
portions to opposed flat portions. The circular arc portions are
centered on a common center. As such, the invention is relatively
easy to manufacture when compared to prior art systems.
Inventors: |
Fenocchi, David M.;
(Arkadelphia, AR) ; Barito, Thomas R.;
(Arkadelphia, AR) |
Correspondence
Address: |
THEODORE W. OLDS
CARLSON, GASKEY & OLDS
400 W. Maple Road, Ste. 350
Birmingham
MI
48009
US
|
Assignee: |
Scroll Technologies
|
Family ID: |
25146885 |
Appl. No.: |
09/789202 |
Filed: |
February 20, 2001 |
Current U.S.
Class: |
418/55.3 |
Current CPC
Class: |
F01C 17/066
20130101 |
Class at
Publication: |
418/55.3 |
International
Class: |
F04C 018/00 |
Claims
1. A scroll compressor comprising: a first scroll member having a
base and a generally spiral wrap extending from said base; a second
scroll member having a base and a generally spiral wrap extending
from said base, said wraps of said first and second scroll member
interfitting to define compression chambers; a shaft driven to
rotate, said shaft being operatively connected to drive said second
scroll member; a crankcase for supporting said second scroll
member; and an Oldham coupling ring positioned between a guiding
structure and said second scroll member, said Oldham coupling ring
having diametrically opposed circular portions centered on a common
point, and having flat portions spaced by 90.degree. from said
circular portions, said flat portions being connected to
circumferential ends of said circular portion by angled portions,
said angled portions being line segments which are not parallel to
said flat portion, and said Oldham coupling ring being operatively
connected to both said guiding structure and said second scroll
member to cause said second scroll member to orbit when said shaft
rotates.
2. A scroll compressor as recited in claim 1, wherein said guiding
structure is on said crankcase.
3. A scroll compressor as recited in claim 2, wherein said circular
arcs are positioned radially inwardly of structure to be received
on said crankcase, and said flat portions are positioned radially
inwardly of structure associated with said second scroll
member.
4. A scroll compressor as recited in claim 3, wherein keys are
formed on said ring and extend into slots in said crankcase, and
said ring further including keys extending into slots from said
second scroll member.
5. A scroll compressor as recited in claim 1, wherein there are at
least two of said angled portions.
6. A scroll compressor as recited in claim 5, wherein there are
three of said angled portions.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to an Oldham coupling which is
manufactured in a simplified manner.
[0002] Scroll compressors are becoming widely utilized in
refrigerant compression applications. In a typical scroll
compressor a first scroll member has a base and a generally spiral
wrap extending from the base. The wrap of the first scroll member
interfits with a spiral wrap of a second scroll member, and the
scroll member is driven to orbit relative to the first scroll
member to compress an entrapped refrigerant. The orbiting movement
is achieved from a rotary motor which is connected to the second
scroll member through a non-rotation coupling. Typically, an Oldham
coupling is provided. The Oldham coupling includes keys which slide
in slot structures on the second scroll member, and which in turn
has keys extending into slots in a crankcase which supports the
second scroll member. In some Oldham couplings, the first scroll
member receives the keys rather than the crankcase. The Oldham
coupling can move in the slots in the crankcase along a linear
path. This allows rotation of the drive motor to be translated into
orbiting movement of the second scroll member.
[0003] The Oldham coupling is a relatively simple part, but it must
meet several design criteria. In particular, the Oldham coupling
must have an interior bore which will allow it to slide as
described above while remaining out of contact with several
components of the compressor which are positioned radially inwardly
of the bore's inner periphery. Moreover, the Oldham coupling ring
must have sufficient wall thickness throughout its entire periphery
such that the part will be sufficiently robust for reliable use.
Finally, the inner periphery of the Oldham coupling ring cannot be
so complex that it is difficult or unduly expensive to
manufacture.
SUMMARY OF THE INVENTION
[0004] In the disclosed embodiment of this invention, an Oldham
coupling ring has a generally cylindrical inner periphery. Two
opposed circular arcs are centered on a common axis, and are
associated with the portions of the Oldham coupling which are
received in keyways in the crankcase. The circular portions have a
pair of angled portions at each of their circumferential extremes.
The angled portions merge into flat portions which are positioned
radially inwardly of the slots on the ring which receive keys from
the orbiting scroll member. The inventive Oldham coupling ring is a
relatively simple part to manufacture, in that its inner periphery
is formed to be generally circular, with the angled portions on the
flat portions being relatively simple portions to manufacture.
[0005] In another embodiment, there are three of the angled
portions at each of the circumferential extends. This adds
additional size to the ring at the area where the angled portions
are merging into the flat portions.
[0006] These and other features of the present invention can be
best understood from the following specification and drawings, the
following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a cross-sectional view through a scroll compressor
incorporating this invention.
[0008] FIG. 2 is a plan view of an Oldham coupling according to the
present invention.
[0009] FIG. 3 is another sectional view.
[0010] FIG. 4 shows another embodiment.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0011] A scroll compressor 20 is shown in FIG. 1 having an orbiting
scroll 22 being driven by a shaft 24. An Oldham coupling 26 is
positioned intermediate a crankcase 25 and the orbiting scroll 22.
As is known, the shaft 24 drives the orbiting scroll 22 through a
slider block connection 27. The Oldham coupling prevents the
orbiting scroll 24 from rotating, and instead transmits the
rotation from the shaft 24 into constrained orbiting movement of
the orbiting scroll 22. As is also known, when the orbiting scroll
22 orbits, it orbits relative to a non-orbiting scroll 29. This
orbiting movement compresses a refrigerant trapped in compression
chambers 31.
[0012] As shown in FIGS. 2 and 3, the Oldham coupling ring 26
functions generally as known in the art. Keyways from orbiting
scroll 22 receive keys 28. Keys 30 are formed at diametrically
opposed positions which are spaced generally by 90.degree. from the
keys 28. The keys 30 fit into slots in the crankcase 25. As is
known, during movement, the Oldham coupling ring 26 will slide
vertically upwardly and downwardly in the direction illustrated in
FIG. 2, and within the slots of crankcase 25. This is as known in
the art. During this movement, the keys 28 are guided into keyways
on orbiting scroll 22, preventing the orbiting scroll 22 from
rotating, and instead constrain the orbiting scroll 22 to
orbit.
[0013] As can be appreciated, as the Oldham coupling 26 moves, it
must avoid portions of the crankcase 25 inwardly of its bore, along
with any other internal structure. Thus, it is desirable to provide
sufficient clearance within the inner periphery of the ring 26 to
avoid contact with any such component. The present invention
provides sufficient clearance, while still maintaining an easy to
manufacture configuration. As shown, opposed circular arcs 32 are
positioned radially inwardly of the keys 30. The arcs 32 are each
centered on a common center 34. Flat portions 36 are positioned
radially inwardly of the keys 28. Angled portions 38 and 40 connect
each flat 36 to one circumferential end of an arc 32. The ring 26
provides sufficient clearance space, while still providing a
relatively easy to manufacture configuration. The prior art had
more complex configurations, and this invention is thus an
improvement. Moreover, the prior art had configurations that would
often result in undesirably thin wall sections that resulted in the
ring not being sufficiently robust.
[0014] FIG. 4 shows another preferred embodiment of the ring 100.
In ring 100, there are three angled portions 138, 140 and 142. This
provides additional wall size in the area immediately adjacent to
the point where the angled portions merge into the flat portion
36.
[0015] A preferred embodiment of this invention has been disclosed,
however, a worker in this art would recognize that certain
modifications would come within the scope of this invention. For
that reason the following claims should be studied to determine the
true scope and content.
* * * * *