U.S. patent application number 11/459122 was filed with the patent office on 2007-01-25 for suspension element for linear compressor.
Invention is credited to Crispin Roger Halkyard, Ian Campbell McGill.
Application Number | 20070020121 11/459122 |
Document ID | / |
Family ID | 37679226 |
Filed Date | 2007-01-25 |
United States Patent
Application |
20070020121 |
Kind Code |
A1 |
Halkyard; Crispin Roger ; et
al. |
January 25, 2007 |
Suspension Element for Linear Compressor
Abstract
In a refrigeration compressor a pair of suspension elements
support a linear compressor within a hermetic shell. Each
suspension element includes a hub component is fixed to one of the
compressor or shell. A substantially rigid ring is secured to the
other of the compressor or shell, an elastic membrane extends
across the area of the ring and is secured to the ring around its
periphery. The hub component is secured to the membrane at the
centre of the ring.
Inventors: |
Halkyard; Crispin Roger;
(North Shore City, NZ) ; McGill; Ian Campbell;
(Auckland, NZ) |
Correspondence
Address: |
TREXLER, BUSHNELL, GIANGIORGI,;BLACKSTONE & MARR, LTD.
105 WEST ADAMS STREET
SUITE 3600
CHICAGO
IL
60603
US
|
Family ID: |
37679226 |
Appl. No.: |
11/459122 |
Filed: |
July 21, 2006 |
Current U.S.
Class: |
417/363 |
Current CPC
Class: |
F04B 35/045
20130101 |
Class at
Publication: |
417/363 |
International
Class: |
F04B 35/00 20060101
F04B035/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 21, 2005 |
NZ |
541406 |
Claims
1. A suspension element for use in supporting a linear compressor
within a hermetic shell, said element comprising: a hub component
adapted for fixing to a first object, a substantially rigid ring,
and an elastic membrane extending across the area of said ring and
secured to said ring around its periphery, said hub component being
secured to said membrane at the centre of said ring.
2. A suspension element as claimed in claim 1 wherein said membrane
is moulded over said ring, and is moulded over at least a part of
said hub component.
3. A suspension element as claimed in claim 1 wherein said membrane
comprises an artificial rubber or polyurethane material.
4. A suspension element as claimed in claim 2 wherein said membrane
comprises an artificial rubber or polyurethane material.
5. A refrigeration system compressor comprising a hermetic housing,
a linear compressor within said hermetic housing, said compressor
including at least two relatively reciprocating parts, with one
part typically being much greater mass than the other part, the
relative reciprocation of the centre of mass of each part occurring
along an axis of reciprocation, and at least a pair of suspension
elements each comprising: a hub component adapted for fixing to a
first object, a substantially rigid ring, and an elastic membrane
extending across the area of said ring and secured to said ring
around its periphery, said hub component being secured to said
membrane at the centre of said ring, the hub portion of each said
suspension element being connected with said compressor part of
greater mass, such that the centre of said hub at least
substantially coincides with said axis of reciprocation, and the
ring portion of each said element being fixed to at least one part
of said hermetic housing.
6. A refrigeration system compressor as claimed in claim 5 wherein
said membrane is moulded over said ring, and is moulded over at
least a part of said hub component.
7. A refrigeration system compressor as claimed in claim 5 wherein
said membrane comprises an artificial rubber or polyurethane
material.
8. A refrigeration system compressor as claimed in claim 6 wherein
said membrane comprises an artificial rubber or polyurethane
material.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to linear compressors, and in
particular linear compressors of the type suitable for use in a
vapour compression refrigeration system.
BACKGROUND TO THE INVENTION
[0002] Linear compressors of a type for use in a vapour compression
refrigeration system are the subject of many documents in the prior
art. One such document is our co-pending PCT patent application
PCT/NZ2004/000108. That specification describes a variety of
developments relating to compressors, many of which have particular
application to linear compressors. The present invention relates to
further improvements to compressor embodiments such as are
described in that patent application, which provides a general
description of an example compressor to which the present invention
may be applied. However the present invention may also be applied
beyond the scope of the particular embodiments of linear compressor
disclosed in that application. Persons skilled in the art will
appreciate the general application of the ideas herein to other
embodiments of linear compressors such as are found in the prior
art.
[0003] PCT/NZ2004/000108 describes a number of arrangements for
suspending a linear compressor assembly in a hermetic shell using
coil springs.
[0004] The present invention relates generally to suspension
elements for suspending the compressor assembly within the hermetic
shell not using coil springs.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a
suspension element with improved characteristics with particular
application to a linear compressor and/or to provide refrigeration
compressors incorporating such elements, or to at least provide the
industry with a useful choice.
[0006] In a first aspect the invention consists in a suspension
element for use in supporting a linear compressor within a hermetic
shell, said element comprising:
[0007] a hub component adapted for fixing to a first object,
[0008] a substantially rigid ring, and
[0009] an elastic membrane extending across the area of said ring
and secured to said ring around its periphery,
[0010] said hub component being secured to said membrane at the
centre of said ring.
[0011] According to a further aspect said membrane is moulded over
said ring, and is moulded over at least a part of said hub
component.
[0012] According to a further aspect said membrane comprises a
natural or artificial rubber, polyurethane material, or rubber
substitute.
[0013] In a further aspect the present invention consists in a
refrigeration system compressor comprising a hermetic housing, a
linear compressor within said hermetic housing, said compressor
including at least two relatively reciprocating parts, with one
part typically being much greater mass than the other part, the
relative reciprocation of the centre of mass of each part occurring
along an axis of reciprocation, and
[0014] at least a pair of suspension elements substantially as set
forth in one or more of the above paragraphs, the hub portion of
each said suspension element being connected with said compressor
part of greater mass, such that the centre of said hub at least
substantially coincides with said axis of reciprocation, and the
ring portion of each said element being fixed to at least one part
of said hermetic housing.
[0015] To those skilled in the art to which the invention relates,
many changes in construction and widely differing embodiments and
applications of the invention will suggest themselves without
departing from the scope of the invention as defined in the
appended claims. The disclosures and the descriptions herein are
purely illustrative and are not intended to be in any sense
limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a side elevation in cross-section of a
refrigeration compressor including a linear compressor suspended in
a housing. The compressor is suspended in the housing at each end
by a suspension element according to a preferred embodiment of the
present invention.
[0017] FIG. 2 is a perspective view of a suspension element
according to a first embodiment of the present invention.
[0018] FIG. 3 is a perspective view of a suspension element
according to a variation of the invention where the membrane does
not cover the entire area bounded by the ring.
DETAILED DESCRIPTION
[0019] Referring to FIG. 1, the compressor for a vapour compression
refrigeration system includes a linear compressor 1 supported
inside a housing 2. Typically the housing 2 is hermetically sealed
and includes a gases inlet port 3 and a compressed gases outlet
port 4. Uncompressed gases flow within the interior of the housing
surrounding the compressor 1. These uncompressed gases are drawn
into the compressor during intake stroke, compressed between the
piston crown 14 and valve plate 5 on the compression stroke, and
expelled through discharge valve 6 into a compressed gases manifold
7. Compressed gases exit the manifold 7 to the outlet port 4 in the
shell through a flexible tube 8. To reduce the stiffness effect of
discharge tube 8 the tube is preferably arranged as a loop or
spiral transverse to the reciprocating axis of the compressor. The
intake to the compression space may be through the piston (with an
aperture and valve in the crown) or through the head, divided to
include suction and discharge manifolds and valves.
[0020] The illustrated linear compressor 1 has, broadly speaking, a
cylinder part and a piston part connected by a main spring. The
cylinder part includes cylinder chassis 10, cylinder head 11, valve
plate 5 and a cylinder liner 12. It also includes stator parts 15
for a linear electric motor. An end portion 18 of the cylinder
part, distal from the head 11, mounts the main spring relative to
the cylinder part. In the illustrated embodiment the main spring is
a combination of coil spring 19 and flat spring 20.
[0021] The piston part includes a hollow piston 22 with sidewall 24
and crown 14. A rod 26 connects between the crown 14 and a
supporting body 30 for linear motor armature 17. The rod 26 has a
flexible portion 28 approximately at the centre of the hollow
piston 22. The linear motor armature 17 comprises a body of
permanent magnet material (such as ferrite or neodymium) magnetised
to provide one or more poles directed transverse to the axis of
reciprocation of the piston within the cylinder liner. An end
portion 32 of armature support 30, distal from the piston 22, is
connected with the main spring 19, 20.
[0022] This briefly describes a linear compressor of a type for
which the suspension element of the present invention is useful.
However it will be appreciated that the usefulness of the
suspension element of the present invention is not restricted to
linear compressors of the type and configuration illustrated. It is
generally applicable where operation of the linear compressor
results in the relative reciprocation of the centre of mass of the
piston carrying part and the centre of mass of the cylinder part
along the linear axis.
[0023] The suspension element of the present invention is most
usefully applied to support the heavier of the relatively moving
assemblies, typically the cylinder part assembly. In the preferred
manner, such as illustrated in FIG. 1, a suspension element 40 is
provided at each extreme end of the compressor. This is so that a
centre of the suspension element can be aligned with the axis of
relative reciprocation of the centres of mass of the two main
assemblies.
[0024] The suspension element of the present invention is
particularly adapted for a linear compressor, which exhibits a
linear oscillating motion rather than a planar oscillating motion.
An isolating suspension element 40 is provided at either end of the
compressor.
[0025] In the preferred embodiments illustrated in FIGS. 2 and 3,
each suspension element 40 includes an elastic membrane 42. The
elastic membrane 42 spans between a central hub 44 and a
surrounding ring 46. One of the hub or ring is fixed to the
compressor. The other of the hub or ring is fixed to the compressor
shell. Fixing the surrounding ring 46 to the compressor is most
likely to be convenient. In the embodiment illustrated, the central
hub 44 is connected to the compressor substantially on the
centreline so that the plane of the membrane 42 is perpendicular to
and intersects the centreline of the compressor. The supporting
ring 46 assists with assembly of the compressor, allowing the
compressor assembly to be placed into a lower half shell fully
supported, with the upper half shell subsequently fitted.
[0026] The hub 44 is adapted for connection to the compressor. For
example the hub 44 may include one or more apertures 43 for
receiving a fastener or fasteners, or may include a suitable clip
for engaging a suitable complementary feature on the
compressor.
[0027] Referring to FIG. 1, the ring 46 is preferably fitted within
a suitable receptacle of the housing. For example an annular groove
53 in the inside surface 55 of the housing may retain the ring. One
half of the annulus of the groove may be formed in each half of the
housing and the ring may be captured in the groove as the housing
is assembled. A number of open clips in each half of the housing
could be provided instead of a continuous groove.
[0028] Each membrane suspension element 40 is preferably arranged
in the housing with the hub 44 secured to a respective end of the
compressor assembly. The suspension element is arranged such that
the plane of the membrane 42 is fully perpendicular to the axis of
reciprocation of the compressor.
[0029] In a variation, illustrated in FIG. 3, the membrane 42 may
not cover the whole area defined by the ring. The membrane may
include a plurality of separate sections (spokes) 57 extending from
hub 44 to ring 46 or the membrane may include a plurality of
openings 59 distributed around the area between hub and ring.
[0030] The membrane 42 may be a high performance natural or
artificial rubber or polyurethane material, or other material
having suitable elastic properties. Examples include natural
rubber, Sunprene (a polypropylene and natural rubber composite
available from DuPont) or thermoplastic rubber. The material may be
moulded over the outer ring component.
[0031] The outer ring component 46 may be of steel or other
suitable rigid material.
[0032] The membrane 42 may also be moulded over the hub component
44, which may be any suitable material, and include any suitable
adaptation for facilitating fixing to the compressor.
* * * * *