U.S. patent application number 09/951064 was filed with the patent office on 2002-03-21 for refrigerant compressor and method for assembling.
Invention is credited to Iversen, Frank Holm, Svendsen, Morten.
Application Number | 20020034450 09/951064 |
Document ID | / |
Family ID | 7903937 |
Filed Date | 2002-03-21 |
United States Patent
Application |
20020034450 |
Kind Code |
A1 |
Svendsen, Morten ; et
al. |
March 21, 2002 |
Refrigerant compressor and method for assembling
Abstract
The invention concerns a refrigerant compressor with a cylinder
block (1), a valve plate (4), a pipe connectable or connected with
a suction muffler, a cover (2) covering the valve plate (4), a
first sealing (3) between cover and valve plate and a second
sealing (5) between valve plate and cylinder block. On assembling
the refrigerant compressor it should be provided that the flow
resistance of the suction gas is reduced as much as possible. For
this purpose, each of the following pairs of members, cover (2) and
pipe (29), pipe (29) and valve plate (4) and valve plate (4) and
cylinder block (1), has an alignment device for its members with at
least two guiding elements, and that the members (2, 29, 4, 1) are
assembled in a direction, which is substantially parallel to the
guiding elements.
Inventors: |
Svendsen, Morten; (Rodekro,
DK) ; Iversen, Frank Holm; (Padborg, DK) |
Correspondence
Address: |
Lee, Mann, Smith, McWilliams, Sweeney and Ohlson
Suite 410
209 S. LaSalle St.
Chicago
IL
60604
US
|
Family ID: |
7903937 |
Appl. No.: |
09/951064 |
Filed: |
September 12, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09951064 |
Sep 12, 2001 |
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09531975 |
Mar 20, 2000 |
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6305912 |
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Current U.S.
Class: |
417/312 ;
29/888.02; 417/313 |
Current CPC
Class: |
F04B 39/0072 20130101;
Y10T 29/49266 20150115; Y10T 29/49236 20150115 |
Class at
Publication: |
417/312 ;
417/313; 29/888.02 |
International
Class: |
F04B 039/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 9, 1999 |
DE |
199 15 918.1 |
Claims
1. Refrigerant compressor with a cylinder block, a valve plate, a
pipe connectable or connected with a suction muffler, a cover
covering the valve plate, a first sealing between cover and valve
plate and a second sealing between valve plate and cylinder block,
characterised in that each of the following pairs of members, cover
(2) and pipe (29), pipe (29) and valve plate (4) and valve plate
(4) and cylinder block (1), has an alignment device for its members
with at least two guiding elements, and that the members (2, 29, 4,
1) are assembled in a direction, which is substantially parallel to
the guiding elements.
2. Refrigerant compressor according to claim 1, characterised in
that the guiding elements additionally align the corresponding
sealings (3, 5).
3. Refrigerant compressor according to claim 1 or 2, characterised
in that the guiding elements are made as pins (30, 31, 35, 36) or
bolts (19).
4. Refrigerant compressor according to one of the claims 1 to 3,
characterised in that the guiding elements (30, 31) are made on the
pipe (29).
5. Refrigerant compressor according to one of the claims 1 to 4,
characterised in that the valve plate (4) is provided with pins
(35, 36), which fit into corresponding holes (13, 14) in the
cylinder block (1).
6. Refrigerant compressor according to one of the claims 1 to 5,
characterised in that a clamp (41) is arranged between the pipe
(29) and the cover (2), which clamp (41) ensures a play between the
pipe (29) and the cover (2).
7. Refrigerant compressor according to one of the claims 1 to 6,
characterised in that a clamp bolt (19) serves as guiding
element.
8. Refrigerant compressor according to claim 7, characterised in
that an opening (24) in the valve plate (4), through which the
clamp bolt (19) is led, has a cross section in the shape of a, if
required rounded, polygon.
9. Refrigerant compressor according to one of the claims 1 to 8,
characterised in that the valve plate (4) has a suction opening
(6), which is arranged in an indentation (46), whose edges
cooperate with a mouth (48) of the pipe (29).
10. A method for assembling a refrigerant compressor with a
cylinder block and a valve plate, the valve plate being, on the
side opposite the cylinder block, covered by a cover, which has an
opening for the adoption of a pipe, which is connected or
connectable with a suction muffler, characterised in that the cover
controls and secures the placement of the pipe, the pipe
controlling and securing the placement of the valve plate and a
sealing between the cover and the valve plate, and the valve plate,
by means of at least one guiding element controlling and securing
the placement of the valve plate in relation to the cylinder block,
and at least one additional guiding element between cover, valve
plate and cylinder block controlling and securing the mutual
placement of cylinder block and valve plate.
11. Method according to claim 10, characterised in that the cover
controls and secures the placement of the suction muffler or its
pipe by means of a resilient member, which retains the pipe of the
suction muffler and secures an isolating play between cover and
pipe.
12. Method according to claim 10 or 11, characterised in that the
suction opening of the valve plate is arranged in an indentation,
the edges of the indentation controlling and securing the suction
muffler pipe, whose mouth cooperates with the edges of the
indentation.
13. Method according to one of the claims 10 to 12, characterised
in that the suction muffler pipe has projections, which, by means
of holes in both sealing and valve plate, control and secure the
mutual placement of the suction muffler and its pipe in relation to
both the sealing and the valve plate.
14. Method according to claim 13, characterised in that the
projections on the suction muffler pipe secure the valve plate and
the sealing by means of tolerance compensating elements, which are
formed in that the cylinder-shaped projections have several outer
edges, which are deformed on assembling.
15. Method according to one of the claims 10 to 14, characterised
in that the valve plate controls and secures the placement of the
valve plate in relation to the cylinder block by means of at least
one pin, a hole for the adoption of the pin being made with
approximately the same diameter as that of the pin.
16. Method according to one of the claims 10 to 14, characterised
in that at least one pin is fixed in the cylinder block, the pin
controlling and securing the placement of the suction valve, and
one of the pins cooperating with a hole in the valve plate, whose
inner diameter is approximately equal to the outer diameter of the
pin.
17. Method according to one of the claims 10 to 16, characterised
in that the mutual placement of valve plate and cylinder block is
controlled and secured by at least one clamp bolt between cover,
valve plate and cylinder block, the diameter of the bolt being
adapted to the holes in valve plate and cylinder block.
18. Method according to one of the claims 10 to 17, characterised
in that one of the holes in the valve plate is made so that a
tolerance compensation is ensured in a first direction, whereas an
accurate position control is ensured in another direction.
Description
[0001] The invention concerns a refrigerant compressor with a
cylinder block, a valve plate, a pipe connectable or connected with
a suction muffler, a cover covering the valve plate, a first
sealing between cover and valve plate and a second sealing between
valve plate and cylinder block. The invention further concerns a
method for assembling a refrigerant compressor with a cylinder
block and a valve plate, the valve plate being, on the side
opposite the cylinder block, covered by a cover, which has an
opening for the adoption of a pipe, which is connected or
connectable with a suction muffler.
[0002] The invention particularly concerns a hermetically enclosed
refrigeration compressor, comprising an electric motor, which, by
means of a rotating shaft and a crank disc connection, drives at
least one piston to a reciprocating movement in a cylinder block,
the cylinder block being closed by a valve plate, which forms the
basis of suction and pressure valves, the valve plate being, on the
side opposite the piston, covered by a cover, which has an opening
for the adoption of a pipe, which is connected with a suction
muffler.
[0003] WO98/22712 describes an electric compressor, in particular
for domestic refrigerators, with a cylinder body, a cylinder head,
a valve plate, which is arranged between head and body of the
cylinder, and which is provided with a gas suction opening. A
muffler is arranged between the inner recess of the compressor
housing and the head of the cylinder. The muffler is formed by a
central gas suction body and an extended part, which extends away
from the body and has an opening for the discharge of the gas
contained in the muffler, the opening being adapted to exact
engagement with the suction opening of the valve plate. On the
outside, the head has a hollow seat or a recess, which is
accessible in the direction of the inner volume of the compressor.
The extended part of the muffler is adapted for fixed and stable
placement in the recess, in a position that permits the
corresponding opening to have an exact and tight engagement with
the opening of the valve plate, to create a mutual connection
between the inside of the muffler and the inside of the cylinder
body, and the head is shaped so that it leaves part of the valve
plate arranged under it, surrounding the suction opening,
uncovered.
[0004] This will ensure an optimum gas suction path, as the pipe of
the suction muffler is only secured in relation to the valve plate
by means of a projection. As the suction muffler is mounted after
the cover, a little space must always be available between the
members with regard to the mounting, and there is a risk that the
pipe of the suction muffler can rotate around the projection,
meaning that it would become wry and offset in relation to the
suction opening of the valve plate. Therefore, the opening in the
pipe of the suction muffler is larger than the suction opening.
However, this gives rise to an edge, which causes an eddy formation
in the suction gas. Thus, the suction opening gets an active flow
area, which is substantially smaller than the geometric area of the
opening. The problem can be further aggravated, when the sealing
between valve plate and cover is wry or offset.
[0005] When producing compressors, a very high accuracy is
required, when an optimum mounting or assembling of the compressor
top part is desired. Very narrow production tolerances are
required. After the welding of the hermetic housing, the compressor
can be exposed to a rather careless treatment during transport,
which causes the risk that, for example, a suction muffler is
displaced, so that the pipe of the suction muffler no longer has
the optimum placement in relation to the suction opening.
Therefore, the compressor in question will work during its whole
life at reduced efficiency.
[0006] As the suction muffler is a rigid body, an undesired
rotation of the suction muffler will influence its suction pipe.
This gives a bad adaptation to the compressor pot, and the
efficiency of the compressor will be reduced for its whole life.
Further, this bad adaptation can have a negative influence on the
noise level of the compressor.
[0007] It can be seen that the assembling of the compressor top
part or the mounting of the compressor top part on the cylinder
block, respectively, can have a substantial influence on the
efficiency and the life of the refrigerant compressor. This also
applies, when the parts forming the cylinder block or the
compressor top part are produced with a relatively high accuracy. A
sufficient accuracy in the production of the individual parts is
anticipated in the following.
[0008] The invention is based on the task of ensuring, in
connection with the assembling of the refrigerant compressor that
the flow resistance of the suction gas is as small as possible.
[0009] With a refrigerant compressor as described in the
introduction, this task is solved in that each of the following
pairs of members, cover and pipe, pipe and valve plate and valve
plate and cylinder block, has an alignment device for its members
with at least two guiding elements, and that the members are
assembled in a direction, which is substantially parallel to the
guiding elements.
[0010] This embodiment does not only ensure that the individual
members of each pair of members are assembled with a predetermined
alignment in relation to each other. This alignment or placement or
positioning in relation to each other will also be maintained for
the remaining life of the compressor, so that in this respect no
changes of the operating qualities will appear. As all neighbouring
pairs of members have one member in common, the alignment device in
each pair of members gives an exact alignment of all parts in
relation to each other, however without a correlation, which could
again lead to an interlocking of individual parts in relation to
each other.
[0011] Preferably, the guiding elements additionally align the
corresponding sealings. Thus, also the sealings between the
individual members are guided precisely, and cannot be displaced in
a way that they influence the suction opening or the flow path for
the suction gas.
[0012] Advantageously, the guiding elements are made as pins or
bolts. Thus, a displacement of the members of a pair of members in
relation to each other is only possible in one direction, namely
along the pins or bolts. A sideways movement is reliably prevented.
This permits the mounting of the individual members of the
compressor top part or the mounting of the compressor top part on
the cylinder block in one direction, which simplifies the mounting
substantially.
[0013] Preferably, guiding elements are made on the pipe. When the
pipe is connected with the valve plate or the cover is fitted on
the pipe, the individual parts will automatically align correctly
in relation to each other.
[0014] Preferably, the valve plate is provided with pins, which fit
into corresponding holes in the cylinder block. These pins can, for
example, be made in advance on the valve plate. In the extreme
case, one single pin will be sufficient.
[0015] Preferably, a resilient clamp is arranged between the pipe
and the cover, which clamp ensures a play between the pipe and the
cover. This play can be available both laterally, that is, in a
level, which is substantially vertical to the valve plate, and on
the top, that is, substantially parallel to the valve plate,
between the pipe and the cover. This play ensures a small air
volume, which can be used as heat isolation.
[0016] Preferably, a clamp bolt serves as guiding element. This
clamp bolt secures the correct position of the compressor top part
to the cylinder block in one of the last steps of the mounting.
This at the same time ensures the axial tension between the
compressor top part and its members or the cylinder block,
respectively.
[0017] Advantageously, an opening in the valve plate, through which
the clamp bolt is led, has a cross section in the shape of a, if
required, rounded polygon. Thus, the cross section of the opening
is easily adapted very accurately to the cross section of the bolt.
The bolt only touches the valve plate at a few sidewalls of the
polygon, which is sufficient for an exact guiding. This does not
significantly prevent the turning of the bolts. At the same time,
the bolt ensures the guiding between the valve plate and the
cylinder block, so that at this point the second connection is
established, beside the connection between the cylinder block and
the valve plate, by means of a pin.
[0018] Preferably, the valve plate has a suction opening, which is
arranged in an indentation, whose edges cooperate with a mouth of
the pipe. Thus, the pipe is guided form-fittingly in the valve
plate, so that a displacement can reliably be prevented. This
applies for both assembling and operation.
[0019] With a method as mentioned in the introduction, this task is
solved in that the cover controls and secures the placement of the
pipe, the pipe controlling and securing the placement of the valve
plate and a sealing between the cover and the valve plate, and the
valve plate, by means of at least one guiding element controlling
and securing the placement of the valve plate in relation to the
cylinder block, and at least one additional guiding element between
cover, valve plate and cylinder block controlling and securing the
mutual placement of cylinder block and valve plate.
[0020] In this connection, the guiding element can be made as a pin
and the additional guiding element as a clamp bolt. The position of
the compressor top part in relation to the cylinder block is
controlled and secured by the use of at least one pin in the valve
plate and a corresponding number of control holes with
approximately the same diameter in the block, at least one clamp
bolt and a corresponding number of control holes controlling and
securing the mutual placement of valve plate and cylinder block.
This gives an optimum suction path for the refrigerant from the
suction muffler to the suction valve opening, the individual
members receiving an optimum mutual placement during production, a
placement, which is also secured during the future operation and
thus maintained. This increases the efficiency of the compressor
and reduces the energy consumption.
[0021] Advantageously, the cover can control and secure the
placement of the suction muffler or its pipe by means of a
resilient member, which retains the pipe of the suction muffler and
secures an isolating play between cover and pipe. This secures the
retaining of the suction muffler pipe in relation to the cover
irrespective of tolerances, and because of the avoidance of a heat
conducting contact between cover and suction muffler pipe, the
heating of the suction gas is reduced.
[0022] The suction opening of the valve plate can be arranged in an
indentation, and the edges of the indentation can control and
secure the suction muffler pipe, whose mouth cooperates with the
edges of the indentation. This gives a high degree of security for
a correct placement of the suction muffler pipe in relation to the
valve plate. At the same time, the connection gets so tight that
the addition of hot refrigerant from the compressor housing as well
as noise can be avoided.
[0023] The suction muffler or its pipe can have projections, which,
by means of holes in both sealing and valve plate, control and
secure the mutual placement of the suction muffler and its pipe in
relation to the sealing and to the valve plate. Thus, the suction
muffler is with a high degree of security retained in the correct
position, so that an undesired flow resistance and undesired heat
conduction to the suction gas is avoided.
[0024] The projections on the suction muffler and its pipe can
secure the valve plate and the sealing by means of tolerance
compensating elements, which are formed in that the cylinder-shaped
projections have several outer edges, which are deformed on
assembling. Thus, during assembling a centering of the projections
is secured, the sealing in all tolerance pairings also being
optimally controlled by the projections.
[0025] The valve plate and thus also the compressor top part can
control and secure the placement of the valve plate in relation to
the cylinder block by means of at least one pin, a hole for the
adoption of the pin being made with approximately the same diameter
as that of the pin. Thus, the placement of the valve plate in
relation to the cylinder is secured. When a piston of the cylinder
block is provided with a recess for the adoption of the suction
valve at top dead centre position of the piston, this recess can be
adapted to the embodiment of the suction valve with almost no play,
and the dead volume, which cannot be emptied when the piston is at
top dead centre position, is reduced. Additionally, a sealing with
a smaller nominal diameter can be used for the piston hole, as the
position of the sealing is precisely controlled.
[0026] Advantageously, at least one pin is fixed in the compressor
block, the pin retaining and controlling the placement of the
suction valve, and one of the pins cooperating with a hole in the
valve plate, whose inner diameter is approximately equal to the
outer diameter of the pin.
[0027] Advantageously, the mutual placement of valve plate and
cylinder block can be controlled and secured by at least one clamp
bolt between cover, valve plate and cylinder block, the diameter of
the bolt being adapted to the holes in valve plate and cylinder
block. Thus, the cover can be guided via the pipe of the suction
muffler, in relation to the valve plate, which again is guided in
relation to the cylinder block. With a precise guiding of the cover
in relation to the valve plate, suction and pressure outlet holes
can be placed closer to each other, without causing a risk of
leaks, as a separating wall in the cover between suction and
discharge side is placed with larger accuracy. This also gives the
opportunity of larger hole diameters in relation to the cylinder
diameter.
[0028] Advantageously, one of the holes in the valve plate is made
so that a tolerance compensation is ensured in a first direction,
whereas an accurate position control is ensured in another
direction.
[0029] In the following, the invention is explained in detail on
the basis of a preferred embodiment in connection with the
drawings, showing:
[0030] FIG. 1 an inexpedient mounting of the suction path of a
compressor
[0031] FIG. 2 a dismounted top part of a compressor
[0032] FIG. 3 a cover cooperating with a suction muffler pipe
[0033] FIG. 4 the compressor top part seen from below
[0034] FIG. 5 a clamp, which can be arranged around the pipe
connection of the suction muffler
[0035] FIG. 6 a section through an alternative embodiment of the
invention.
[0036] FIG. 1 shows an inexpedient mounting of the suction path of
a compressor. A pipe 29 of a suction muffler is offset in relation
to a sealing 3, which again is offset in relation to a valve plate
4 and its suction opening 7. The inlet path of the gas is thus
reduced, and the flow resistance is increased. This reduces the gas
quantity at each cylinder filling. The problem is aggravated by an
eddy formation, as shown in FIG. 1, as this may cause a back-flow
of the gas. The flow area of the suction path can therefore be
substantially reduced in relation to the geometrical area. When, at
the same time, the gas flows backwards, the gas quantity can be
substantially reduced, thus reducing the efficiency of the
compressor.
[0037] FIG. 2 shows a dismounted compressor top part with a
cylinder block 1, on which a cover 2, a first sealing 3, a valve
plate 4 and a second sealing 5 are mounted. The valve plate 4 has a
suction opening 6 and a discharge opening 7, the suction opening 6
being covered under the valve plate by a suction valve 37 (FIG. 4),
the discharge opening being closed by a discharge valve (not
shown), which can be mounted in an indentation 8. The valve plate 4
has openings 9 and 10 for the adoption of projections 30, 31 on the
suction muffler pipe 29 (FIG. 3), the projections 30, 31 being
guided through holes in the sealing 3. The suction valve is
countersunk in the cylinder block 1, and is retained in holes 13,
14 in the cylinder block by means of pins 35, 36 (FIG. 4), which
again are fixed in holes 15, 16 in the valve plate 4.
[0038] The assembling of the compressor top part occurs by means of
bolts 17, 18, 19, 20. The bolts go through openings in the cover 2
and the first sealing 3, before passing through holes 21, 22, 23,
24 in the valve plate, from where they go through the second
sealing 5, before reaching the cylinder block 1, which has threaded
holes 26, 27, 28, 29 for the adoption of the bolts 17, 18, 19,
20.
[0039] FIG. 3 shows a cover 2, which cooperates with a suction
muffler pipe 29, which is connected with a suction muffler, not
shown. The pipe 29 has two projections 30, 31, which cooperate with
the holes 11, 12 in the first sealing 3. The projections 30, 31
also cooperate with the holes 9, 10 in the valve plate 4.
Additionally, the pipe 29 is provided with projections in the shape
of shoulders 32, 33, which cooperate with corresponding recesses 38
in the cover 2 (FIG. 4).
[0040] FIG. 4 differs from the FIGS. 1 and 2 in that the compressor
top part is seen from below. Thus, the pins 35, 36 of the valve
plate and also the suction valve 37 can be seen. The suction valve
37 has holes, which cooperate with the pins 35, 36, thus securing
the position of the sealing. The pins extend through the sealing 5
into the holes 13, 14 in the cylinder block 1 (FIG. 1). The cover 2
has a hollow space, which is used for pulsation suppression of the
pressurised gas.
[0041] When assembling the compressor, firstly, the sealing 3 is
placed on the valve plate 4, so that the holes 9, 11 and 10, 12
overlap each other. In these holes the pipe 29 with the projections
30, 31 is inserted, in a way that the pipe 29, the sealing 3 and
the valve plate 4 are positioned correctly in relation to each
other. The valve 37 is mounted, and the sealing 5 is pushed onto
the pins 35, 36. A clamp 41 (FIG. 5) is mounted on the pipe 29, and
on this preliminary unit the cover 2 is mounted, which is then
positioned exactly on the pipe 29 by means of the recesses 38 and
the shoulders 32, 33. The top part can now be mounted on the
cylinder block 1. At least one of the pins 35, 36 of the valve
plate now fits exactly into one of the corresponding holes 13, 14
in the cylinder block 1. Thus, the translatory placement of the
valve plate and thus also of the compressor top part in relation to
the cylinder block 1 is ensured. The bolts 17 to 20 are mounted in
the cover 2, and in this case the bolt 19 is positioned over the
rounded rectangle 24 in the valve plate 4, the top part thus being
secured against rotation. The other bolts and screw holes in the
sealings 3 and 5, in the cover 2 and in the valve plate 4 have no
guiding effect, and only serve the purpose of holding together the
top part and the cylinder block.
[0042] In this case, the clamp bolt 19 only has to guide the valve
plate, and therefore only the guide hole 24 of this bolt must be
accurate. The other screw holes are made with such large diameters
that they are certain not to have any guiding effect. If they would
have a guiding effect, this could lead to a jamming with the piston
control system.
[0043] Thus, it is ensured that all members are secured in relation
to each other with at least two different mechanisms. This reduces
the risk of a wry or offset mounting or of the members being
displaced during transport or operation, thus keeping the
efficiency of the compressor unchanged.
[0044] FIG. 5 shows the resilient clamp 41, which can be arranged
around the pipe connection of the suction muffler. The clamp has
supporting legs 42, which, after mounting, bear on the sidewalls of
the cover and ensure a play. The clamp 41 also has arms 43, which
rest on the cover 2 and provide an isolating play between the
suction muffler pipe 29 and the cover 2.
[0045] FIG. 6 shows a section through an alternative embodiment of
the invention. A pipe 44, which is connected with a suction
muffler, is mounted in an indentation 46 in a valve plate 45. The
suction muffler pipe has a straight pipe part 49, which is followed
by an angle part, which carries a connection 4, which cooperates
with the indentation of the valve plate.
[0046] For the whole life of the compressor, this method ensures a
correct adaptation of the suction path of the compressor. Merely
one additional, exactly placed clamp bolt for the guiding of the
valve plate and thus the compressor top part is required. The
tolerances of the remaining clamping holes in the valve plate, the
two sealings and the cover can thus be increased.
* * * * *