U.S. patent application number 11/918285 was filed with the patent office on 2009-08-27 for refrigerant compressor.
This patent application is currently assigned to ACC AUSTRIA GMBH. Invention is credited to Walter Brabek, Alfred Freiberger, Guenther Zippl.
Application Number | 20090214367 11/918285 |
Document ID | / |
Family ID | 36593060 |
Filed Date | 2009-08-27 |
United States Patent
Application |
20090214367 |
Kind Code |
A1 |
Brabek; Walter ; et
al. |
August 27, 2009 |
Refrigerant Compressor
Abstract
A hermetically encapsulated refrigerant compressor having a
hermetically sealed compressor housing, in whose interior a
piston-cylinder unit operates, whose cylinder housing (1) is closed
using a valve plate (2) having a pressure hole (10) and a suction
hole (16), and a suction channel and a pressure channel are
provided. Preferably V-shaped sealing beads (23) or sealing
projections (22) are provided in the valve plate (2) and the front
face of the component (9) forming the suction channel is equipped
along its suction contact edge (17) with sealing projections (22)
or sealing beads (23) essentially corresponding to the V-shaped
sealing beads (23) or sealing projections (22), the sealing
projections (22) being implemented differently from the sealing
beads (23) in their geometrical design and/or having a different
volume.
Inventors: |
Brabek; Walter;
(Fuerstenfeld, AT) ; Zippl; Guenther; (Graz,
AT) ; Freiberger; Alfred; (Grosswilfersdorf,
AT) |
Correspondence
Address: |
COLLARD & ROE, P.C.
1077 NORTHERN BOULEVARD
ROSLYN
NY
11576
US
|
Assignee: |
ACC AUSTRIA GMBH
Furstenfeld
AT
|
Family ID: |
36593060 |
Appl. No.: |
11/918285 |
Filed: |
March 30, 2006 |
PCT Filed: |
March 30, 2006 |
PCT NO: |
PCT/EP2006/061196 |
371 Date: |
January 5, 2009 |
Current U.S.
Class: |
417/559 |
Current CPC
Class: |
F04B 39/123 20130101;
F04B 39/125 20130101; F04B 39/06 20130101 |
Class at
Publication: |
417/559 |
International
Class: |
F04B 39/10 20060101
F04B039/10 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 12, 2005 |
AT |
GM 223/2005 |
Jan 27, 2006 |
AT |
GM 59/2006 |
Claims
1. A hermetically encapsulated refrigerant compressor having a
hermetically sealed compressor housing, in whose interior a
piston-cylinder unit, which compresses a refrigerant, operates,
whose cylinder housing (1) is closed using a valve plate (2) having
a pressure hole (10) and a suction hole (16), and a suction channel
and a pressure channel are provided, via which refrigerant is
suctioned via a suction valve (32) into the suction hole (16) and
is compressed via a pressure valve (15) from the pressure hole (10)
in the pressure channel, the suction channel being formed by a
channel-shaped component (9), which is connected sealingly along a
suction contact edge (17) to the valve plate (2) and which connects
the suction hole (16) to a preferably provided suction noise damper
(3), wherein preferably V-shaped sealing beads (23) or sealing
projections (22) are provided in the valve plate (2) and the front
face of the component (9) forming the suction channel, which faces
toward the valve plate (2), is equipped along its suction contact
edge (17) with sealing projections (22) or sealing beads (23)
essentially corresponding to the V-shaped sealing beads (23) or
sealing projections (22), whereas the sealing projections (22)
being implemented differently from the sealing beads (23) in their
geometrical design and/or having a different volume.
2. A hermetically encapsulated refrigerant compressor having a
hermetically sealed compressor housing, in whose interior a
piston-cylinder unit, which compresses a refrigerant, operates,
whose cylinder housing (1) is closed using a valve plate (2) having
a pressure hole (10) and a suction hole (16), and a suction channel
and a pressure channel are provided, via which refrigerant is
suctioned via a suction valve (32) into the suction hole (16) and
is compressed via a pressure valve (15) from the pressure hole (10)
in the pressure channel, the suction channel being formed by a
channel-shaped component (9), which is connected sealingly to the
valve plate (2) along a suction contact edge (17) and which
connects the suction hole (16) to a preferably provided suction
noise damper (3), wherein the pressure channel is formed by an
independent component (8) completely enveloping the pressure
channel, which is tightly connected to the valve plate (2) along a
pressure contact edge (13) formed by an end section of the
component (8), preferably V-shaped sealing beads (23) or sealing
projections (22) being provided in the valve plate (2) and the
front face of the component (8) forming the pressure channel, which
faces toward the valve plate (2), being equipped along its pressure
contact edge (13) with sealing projections (22) or sealing beads
(23) essentially corresponding to the V-shaped sealing beads (23)
or sealing projections (22), whereas the sealing projections (22)
being implemented as different in their geometrical design from the
sealing beads (23) and/or having a different volume.
3. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein the pressure hole (10) and the movable part of
the pressure valve (15) are situated inside the area enclosed by
the pressure contact edge (13).
4. The hermetically encapsulated refrigerant compressor according
to claim 3, wherein the ratio of the cross-sectional area of the
pressure hole (10) to the area enclosed by the pressure contact
edge (13) is greater than 1/12.
5. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein the area enclosed by the pressure contact edge
(13) exceeds the area of the mobile parts of the pressure valve
(15) by less than 50%.
6. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein the component (8) forming the pressure channel
has a section (8a) directly adjoining the pressure hole (10) and
leading away from the valve plate (2), and a further section (8b)
adjoining this section (8a), which runs radially outward in
relation to the cylinder hole, preferably at a distance to the
valve plate (2) and preferably parallel thereto.
7. The hermetically encapsulated refrigerant compressor according
to claim 6, wherein the section (8a) leading away from the valve
plate (2) and/or the further section (8b) of the pressure channel
(8) is/are manufactured from plastic.
8. The hermetically encapsulated refrigerant compressor according
to claim 6, wherein an insulating material, preferably made of
rubber or plastic, is situated between the further section (8b) and
the valve plate (2).
9. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein the component (8) forming the pressure channel
and the component (9) forming the suction channel are each
manufactured in one piece and/or are preferably manufactured
jointly in one piece, the two components (8, 9) manufactured
jointly in one piece preferably being in contact along an
intermediate wall, but at least along connecting webs.
10. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein the pressure valve (15) closing the pressure
hole (10) is fastened in the component (8) forming the pressure
channel.
11. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein a pressure chamber (8a), which does not fall
below a predefined minimum volume, is provided in the component (8)
forming the pressure channel.
12. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein the pressure chamber (8a) is situated directly
adjoining the pressure hole (10) in the component (8) forming the
pressure channel.
13. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein a clamping element (7) is provided, which
clamps the valve plate (2) to the cylinder housing (1) along at
least a section of its circumference, but preferably along the
entire circumference.
14. The hermetically encapsulated refrigerant compressor according
to claim 13, wherein the clamping element (18) has an essentially
J-shaped cross-section.
15. The hermetically encapsulated refrigerant compressor according
to claim 13, wherein the clamping element (7) is implemented as
circular.
16. The hermetically encapsulated refrigerant compressor according
to claim 13, wherein one or more undercuts (27), which are
engageable with an end section of the clamping element (7), are
provided on the cylinder housing (1).
17. The hermetically encapsulated refrigerant compressor according
to claim 16, wherein the other end section of the clamping element
(7) forms a first clamping section (7b), which clamps the valve
plate (2) to the cylinder housing (1).
18. The hermetically encapsulated refrigerant compressor according
to claim 13, wherein the clamping element (7) has at least one
further clamping section (7a), which clamps the components (8, 9)
forming the pressure channel or the suction channel to the valve
plate (2) or in the suction hole (16) and/or the pressure hole (10)
respectively.
19. The hermetically encapsulated refrigerant compressor according
to claim 13, wherein a further clamping element (29) is provided,
which is engageable on the clamping element (7) and clamps the
components (8, 9) forming the pressure channel or the suction
channel to the valve plate (2) or in the suction hole (16) and/or
the pressure hole (10) respectively.
20. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein separate fasteners (11) are provided or a
separate fastener (7b) is provided for fastening the valve plate
(2) to the cylinder housing (1).
21. The hermetically encapsulated refrigerant compressor according
to claim 20, wherein the separate fasteners are screws (11).
22. The hermetically encapsulated refrigerant compressor according
to claim 20, wherein a clamping element is provided, which is
engageable on the cylinder housing (3) and clamps the components
(8, 9) forming the pressure channel or the suction channel to the
valve plate (2) or in the suction hole (16) and/or the pressure
hole (10) respectively.
Description
[0001] The present invention relates to a hermetically encapsulated
refrigerant compressor having a hermetically sealed compressor
housing, in whose interior a piston-cylinder unit, which compresses
a refrigerant, operates, whose cylinder is closed using a valve
plate having a pressure hole and a suction hole, and a suction
channel and a pressure channel are provided, via which refrigerant
is suctioned via a suction valve into the suction hole and is
compressed via a pressure valve from the pressure hole into the
pressure channel, the suction channel being formed by a
channel-shaped component, which is connected to the valve plate to
form a seal along a suction contact edge and connects the suction
hole to a preferably provided suction noise damper, according to
the preamble of Claim 1 or 2.
[0002] Such refrigerant compressors have been well-known for some
time and predominantly are used in refrigerators or refrigerated
cases. The piece count produced yearly is accordingly high.
[0003] Although the energy consumption of a single refrigerant
compressor is only between 50 and 150 W, a very high energy
consumption results upon consideration of all refrigerant
compressors used worldwide, which is increasing continuously
because of the rapidly progressing development of the so-called
developing countries.
[0004] Any technical improvement which is performed on a
refrigerant compressor and increases its efficiency thus conceals
an enormous savings potential for energy when multiplied by the
refrigerant compressors in use worldwide.
PRIOR ART
[0005] The refrigerant process per se has been known for some time.
The boiling refrigerant is vaporized in the evaporator by energy
absorption from the space to be cooled and finally overheats and is
pumped to a higher energy level using the refrigerant compressor,
where it dissipates heat via a condenser and is conveyed back into
the evaporator via a throttle, in which pressure reduction and
cooling of the refrigerant occurs.
[0006] The greatest and most important potential for a possible
improvement of the efficiency is the reduction of the temperature
of the refrigerant at the beginning of its compression procedure,
i.e., upon intake into the cylinder of the piston-cylinder unit.
Any reduction of this so-called suction temperature therefore
causes, like the reduction of the temperature during the
compression procedure and, connected thereto, the expulsion
temperature, a reduction of the required work for the compression
procedure.
[0007] In known hermetic refrigerant compressors according to the
prior art, the refrigerant is strongly heated on its way from the
evaporator (cooling space) to the intake valve of the
piston-cylinder unit because of the construction.
[0008] The intake of the refrigerant occurs via a suction channel
coming directly from the evaporator during an intake stroke of the
piston-cylinder unit. From this suction channel, the refrigerant is
suctioned via a suction noise damper and a suction valve into the
interior of the cylinder, where it is compressed by the piston and
expelled via a pressure valve from the interior of the cylinder
into a pressure channel leading to the cooling chamber. Known
refrigerant compressors have a construction in which the cylinder
housing accommodating the piston is terminated by a valve plate
having the suction and/or pressure holes. The valve plate is used
as a seat for a cylinder cover, which is typically screwed to the
valve plate and the cylinder housing. The cylinder cover has
intermediate walls, which divide the cavity between cylinder cover
and valve plate into chambers, which then form the suction and/or
pressure channel, via which the refrigerant is suctioned into the
cylinder or expelled therefrom.
[0009] The suction channel typically discharges directly into the
interior of the compressor housing, which is encapsulated
hermetically sealed, in proximity to the entry opening into a
suction noise damper, which reduces the intake noise of the
piston-cylinder unit and is typically constructed from multiple
volumes which are connected to one another, as well as having the
cited entry opening and an exit opening which presses against the
suction hole of the valve plate to form a seal.
[0010] In addition to the cited discharge of the suction pipe into
the compressor housing in proximity to the entry opening into the
suction noise damper, embodiment variants are also known, for
example, from WO 03/038280, in which the suction channel is
conducted directly into the suction noise damper, without a bypass
via the interior of the compressor housing. In this way, the mixing
of the refrigerant flows, which results in heating of the
refrigerant at the beginning of the compression procedure, may not
occur. However, this solution has the disadvantage that there is
usually a greater pressure drop during the intake, which reduces
the volumetric efficiency and thus the energy efficiency to varying
degrees.
[0011] All known refrigerant compressors have an identical
construction of the piston-cylinder unit, however, in particular of
the cylinder housing, which is closed using a valve plate and a
cylinder cover adjoining thereto. The cylinder cover preferably
covers the entire valve plate, which also has the suction hole and
the pressure hole. The suction valve temporarily closing the
suction hole and the pressure valve temporarily closing the
pressure hole are also situated on the valve plate. The cylinder
cover is typically provided with a recess for the suction channel,
and/or for the end section of the suction noise damper, which
discharges into the suction hole.
[0012] The refrigerant heated by the compression procedure is
pressed via the pressure valve and the pressure hole out of the
cylinder into the cylinder cover, where, because of the design of
the cylinder cover, it fills up the cylinder cover completely at
least in the section forming a pressure channel and thus also comes
into contact with the valve plate forming a part of this pressure
channel. Because of this, the temperature of the valve plate
essentially corresponds to the temperature of the compressed
refrigerant. Because the gas in the interior of the cylinder is
colder than the valve plate over more than 300.degree. crank angle,
a heat flow occurs directly from the valve plate or indirectly from
the valve plate to the cylinder wall and from there to the gas in
the interior of the cylinder, which has a negative effect on the
energy efficiency.
[0013] Furthermore, the high temperature existing in the cylinder
cover also causes a heat flow in the direction of the end section
of the suction noise damper, which is enclosed by the cylinder
cover, but by which the refrigerant coming from the suction noise
damper, which is still to be compressed, is also undesirably
heated. In summary, it may thus be stated that the known
refrigerant compressor designs act contrary to the object cited at
the beginning, namely a reduction of the suction temperature and
the expulsion temperature, because of their cylinder cover
design.
DESCRIPTION OF THE INVENTION
[0014] It is the object of the present invention to be able to
guarantee suppression of outflow of the refrigerant from the
channels into the interior of the compressor housing. This is to
support a significant reduction of the suction temperature and the
expulsion temperature. In particular, it is an object of the
present invention to connect the suction and/or pressure channel
hermetically sealed to the valve plate reliably.
[0015] This is made possible according to the present invention by
the characterizing features of Claim 1 or 2.
[0016] The characterizing features of Claims 1 or 2 describe a
preferred embodiment variant of the sealed connection of the
components forming the suction and/or pressure channel to the valve
plate to be able to guarantee suppression of outflow of the
refrigerant from the channels into the interior of the compressor
housing. The implementation of the sealing beads in connection with
the sealing projections causes a significantly lower pressure force
to be required between pressure and/or suction channel and valve
plate than between cylinder cover and valve plate in known cylinder
heads.
[0017] The known embodiment variants described above additionally
have the disadvantage that the refrigerant heats up too much on its
path from the entry into the interior of the compressor housing to
the suction hole. Measurements have shown that heating by more than
20.degree. C. occurs between a point in the suction channel shortly
before the entry into the compressor housing and the first volume
of the suction noise damper. The main cause of this undesired
heating of the refrigerant is the fact that fresh refrigerant
flowing from the suction channel into the compressor housing is
mixed with refrigerant already located in the compressor housing.
However, this refrigerant has a higher temperature because of the
heat released by the piston-cylinder unit in operation than the
refrigerant flowing from the suction channel into the compressor
housing, so that a mixing temperature results upon mixing of the
two refrigerant streams which is higher in any case than the
temperature of the refrigerant in the suction channel before entry
into the compressor housing. The cause of the mixing is the fact
that the intake valve, which is seated on the valve plate and
alternately closes and releases the suction hole, only releases the
suction hole over a crankshaft angle range of 180.degree. and
therefore refrigerant may only be suctioned into the cylinder of
the piston-cylinder unit within this time. The suction valve is
closed during the other 180.degree. crankshaft angle range, the
compression cycle, but the refrigerant coming from the evaporator
has a nearly constant mass flow, so that it still flows into the
compressor housing even when the suction valve is closed and
remains there and cools the piston-cylinder unit and heats up at
the same time. In addition, due to the pressure oscillations during
the compression phase, further flow procedures occur from the
compressor housing to the suction noise damper and vice versa,
which cause additional mixing of the refrigerant.
[0018] Therefore, an independent component is also provided
according to Claim 2, which forms the pressure channel and
completely envelops it. By direct connection of this component to
the pressure hole, the pressure channel is completely thermally
separated from the valve plate. These components allow the direct
exit of the hot, compressed refrigerant via the pressure hole into
the pressure channel, without having to flow out along a section of
the valve plate. Only the area of the valve plate immediately
surrounding the pressure hole comes into contact with the hot
refrigerant on its side facing away from the piston. The heat
transfer from the hot, already compressed refrigerant to the valve
plate may thus be drastically reduced in relation to typical
cylinder heads in refrigerant compressors. The valve plate and the
cylinder wall remain cooler and thus allow a dissipation of the
heat from the interior of the cylinder housing, and/or prevent the
flow of heat into the gas in the cylinder. Furthermore, in this
way, the heat transfer from the valve plate to the suction hole and
thus into the suction channel may also be reduced, by which the
intake temperature may be lowered.
[0019] The area of the pressure channel which is incident on the
valve plate, i.e., the area which lies inside the pressure contact
edge, may be dimensioned precisely and optimized in regard to heat
transfer by the characterizing features of Claim 4. It is necessary
on one hand for the pressure hole to be inside this area and on the
other hand for the transition between pressure channel and pressure
hole to be implemented for favorable flow and nonetheless allow a
sealed connection. Because, according to the present invention, the
pressure channel or more precisely the last section of this channel
is incident essentially perpendicularly on the pressure hole and
thus on the valve plate, to prevent a heat transfer from the valve
plate to the pressure channel or vice versa, the shape of the
pressure contact edge may be selected in such a way that the
refrigerant only flows around the valve plate along a small
area.
[0020] According to the present invention, the ratio of the
cross-sectional area of the pressure hole to the area enclosed by
the pressure contact edge is more than 1/12.
[0021] According to the characterizing features of Claim 6, the
component forming the pressure channel has a section directly
adjoining the pressure hole and leading away from the valve plate
and a further section adjoining this section, which runs radially
outward in relation to the cylinder hole, preferably at a distance
to the valve plate and preferably parallel thereto. The compressed
refrigerant may thus be conveyed rapidly away from the valve plate
and its heat dissipation to the valve plate may be prevented or
reduced.
[0022] According to the characterizing features of Claim 7, the
section leading away from the valve plate and/or the further
section of the pressure channel is/are manufactured from poorly
conductive plastic, by which the heat dissipation of the compressed
refrigerant may be reduced still further.
[0023] According to the characterizing features of Claim 8, an
insulating material, preferably made of rubber or plastic, is
situated between the further section and the valve plate to reduce
the heat transfer from the compressed refrigerant to the valve
plate still further.
[0024] The characterizing features of Claim 9, namely the one-piece
manufacture of each component and/or the joint one-piece
manufacture of the two components forming the pressure and suction
channels, in the latter case the two components manufactured
jointly in one piece being in contact at least along an
intermediate wall, provide the advantage of simplified manufacture.
The component comprising the two channels may thus be manufactured
from plastic using injection molding, by which the heat transfer
from the pressure channel into the interior of the compressor
housing, from the interior of the compressor housing into the
suction channel, and in the area of the suction or pressure contact
edge into the valve plate may be reduced still further.
[0025] The characterizing features of Claim 10 provide that the
pressure valve closing the pressure hole is situated in the
component forming the pressure channel. The valve plate may thus be
manufactured more simply, i.e., in fewer work steps, because
providing a fastener for the pressure valve in the valve plate is
no longer necessary. Simultaneously, implementing this feature
allows pre-assembling of pressure channel and pressure valve
and/or, jointly with the features of Claim 10, pre-assembling of
pressure channel and pressure valve including suction channel.
[0026] According to the characterizing features of Claims 11 and
12, namely the implementation of the pressure chamber in the
pressure channel directly adjoining the pressure hole, excess
pressures in the pressure channel may be avoided during expulsion
of the refrigerant from the cylinder, which would result in a
reduction of the energy efficiency.
[0027] According to the characterizing features of Claims 13, 14,
and 15, the valve plate is fastened to the cylinder housing a
clamping element which clamps the valve plate to the cylinder
housing at least along a section of its circumference, but
preferably along the entire circumference. By this measure, the
deformation and the costs of the cylinder mold may be drastically
reduced in relation to typical cylinder heads of refrigerant
compressors, because screws are no longer required for fastening
the valve plate to the cylinder housing.
[0028] The clamping element is engageable at an end section on
undercuts provided on the cylinder housing according to the
characterizing features of Claim 16.
[0029] According to the characterizing features of Claim 17, the
valve plate is clamped to the cylinder housing the other end
section, which forms a first clamping leg.
[0030] The cylinder housing may also be provided with a shoulder,
in which the valve plate is at least partially countersunk to allow
positioning thereof, because positioning by screw connections as is
known in typical cylinder heads of refrigerant compressors is no
longer possible because of the clamping, in a preferred embodiment
variant, the surface of the valve plate facing away from the piston
terminating flush with the cylinder housing.
[0031] According to the characterizing features of Claim 18, the
components forming the suction and/or pressure channels are
fastened to the valve plate using further clamping legs situated on
the clamping element. Therefore, the use of screws for fastening
the cylinder head may be entirely dispensed with.
[0032] As an alternative thereto, according to the characterizing
feature of Claim 19, a separate further clamping element may be
provided, which clamps the components forming the suction and
pressure channels to the valve plate, this separate clamping
element being able to be engaged with the clamping element.
[0033] The characterizing features of Claims 20 through 22 describe
a further preferred embodiment of the present invention, according
to which the valve plate is fastened using separate fasteners, such
as screws, to the cylinder housing, but the components forming the
pressure and/or suction channels are clamped to the valve plate,
thus, a combination of clamping and screwing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] In the following, the present invention is described in
greater detail on the basis of exemplary embodiments.
[0035] FIG. 1 shows an axonometric view of a piston-cylinder unit
including cylinder head according to the present invention
[0036] FIG. 2 shows a frontal view of a cylinder head
[0037] FIG. 3 shows an axonometric view of a piston-cylinder head
including cylinder head without clamping element
[0038] FIG. 4 shows an axonometric sectional detail view of a
cylinder head
[0039] FIG. 5 shows a view in the direction of the crankshaft axis
of a cylinder head including cylinder housing and crankcase
[0040] FIG. 6 shows a section along line AA from FIG. 2
[0041] FIG. 7 shows a view in the direction of the crankshaft axis
of a cylinder head including cylinder housing and crankcase without
clamping element
[0042] FIG. 8 shows an axonometric view of the component forming
the pressure channel
[0043] FIG. 8a shows an axonometric view of the component forming
the pressure channel in section
[0044] FIG. 9 shows an alternative embodiment variant of a cylinder
head according to the present invention
[0045] FIG. 10 shows a sectional view of the alternative embodiment
variant from FIG. 9 along plane A1 from FIG. 9
[0046] FIG. 11 shows a detail view from FIG. 10
[0047] FIG. 12 shows a sectional view along plane A from FIG. 9
[0048] FIG. 13 shows a further alternative embodiment variant of a
cylinder head
[0049] FIG. 14 shows a sectional view along plane B from FIG.
13
[0050] FIG. 15 shows an additional alternative embodiment variant
of a cylinder head
[0051] FIG. 16 shows a sectional view along plane C from FIG.
15
[0052] FIG. 17 shows another alternative embodiment variant of a
cylinder head
[0053] FIG. 18 shows a sectional view along plane D from FIG.
17
[0054] FIG. 19 shows a sectional view of a cylinder head having
O-ring seal
[0055] FIG. 20 shows a sectional view of a cylinder head having
paper seal
[0056] FIG. 21 shows an illustration of a sealing system according
to the present invention in section along plane E from FIG. 22
[0057] FIG. 22 shows an additional further embodiment variant of a
cylinder head according to the present invention from FIG. 21
[0058] FIG. 23 shows a sectional view along plane F from FIG.
22
[0059] FIG. 24-31 show sectional views of an alternative sealing
system according to the present invention
[0060] FIG. 32 shows an additional, alternative embodiment variant
of a cylinder head
[0061] FIG. 33 shows a sectional view along plane G from FIG.
32
[0062] FIG. 34 shows a top view of a cylinder head from FIG. 32
[0063] FIG. 35 shows a sectional view along plane H from FIG.
34
[0064] FIG. 36 shows a further exemplary embodiment of a cylinder
head
[0065] FIG. 37 shows an axonometric view of the cylinder housing
including clamping element from FIG. 36
[0066] FIG. 38 shows a further exemplary embodiment of a cylinder
head
[0067] FIG. 39 shows the exemplary embodiment from FIG. 38 without
the components forming the pressure and suction channels.
WAYS OF IMPLEMENTING THE INVENTION
[0068] FIG. 1 shows an axonometric view of a cylinder head,
sections of the cylinder housing 1, the valve plate 2, and the
suction noise damper 3 including intake opening 3a being
visible.
[0069] The fundamental construction of the hermetically
encapsulated refrigerant compressor which is the subject matter is
known per se. The piston-cylinder-motor unit essentially comprises
a cylinder housing 1 and the piston 4, which executes a stroke
movement therein, as well as a crankshaft bearing 5 in a crankcase
5a, which is situated perpendicularly to the cylinder axis 6. The
crankshaft bearing 5 accommodates a crankshaft (not shown) and
projects into a central hole of the rotor of an electric motor
(also not shown). The rotational movement of the crankshaft is
transferred to the piston 4 in a way also known per se via a
connecting rod (not shown). A suction noise damper 3 is situated on
the cylinder head itself, which is to reduce the noise development
to a minimum during the intake procedure of the refrigerant.
[0070] FIG. 1 and FIG. 2 show an embodiment variant of a cylinder
head in the completely assembled state, i.e., having a clamping
element 7, while in contrast FIG. 3 shows the same cylinder head
but without clamping element 7. The pressure channel is formed by
the component 8 according to the present invention, and the suction
channel is formed by the component 9. Both components 8, 9 are
independent of one another and are particularly also independent of
the valve plate 2, to which they are connected to form a seal along
a contact edge, however, namely a pressure contact edge 13 or a
suction contact edge 17, which will be discussed in greater detail
later. In other words, the components 8, 9, which may also be
referred to as pressure channel 8 and suction channel 9, each
delimit a completely autonomous channel, which they completely
envelop up to incidence on the valve plate. According to the
present invention, the component 8 forming the pressure channel has
a section 8a, which directly adjoins the pressure hole 10 and leads
away from the valve plate 2, and a further section 8b adjoining
this section 8a, which runs essentially radially outward in
relation to the cylinder hole, and preferably parallel to the valve
plate 2 at a distance Z thereto (see also FIGS. 10 and 11).
[0071] The distance Z between the component 8 and the valve plate 2
causes optimum insulation of the valve plate 2 from the pressure
channel, so that heat transfer from the compressed, hot refrigerant
in the pressure channel 8 to the valve plate 2 and to the suction
channel 9 is strongly prevented here.
[0072] Directly adjoining the pressure hole 10 situated in the
valve plate 2, which is visible in FIG. 4, for example, but is
concealed in FIGS. 1 and 2, the component 8 forms a pressure
chamber, which is situated in the section 8a of the pressure
channel 8 leading away from the valve plate 2 and does not fall
below a defined minimum volume as a fraction of the cooling
performance. This pressure chamber, which is also identified by 8a
in the following, is used for the purpose of avoiding excess
pressures possibly arising during expulsion of the refrigerant from
the cylinder. The pressure channel 8 then passes into the further
section 8b, which leads the refrigerant out of the compressor
housing.
[0073] As is obvious from FIG. 1, the components 8, 9 are pressed
by a clamping element 7 against the valve plate 2. The clamping
element 7 shown in the exemplary embodiment of FIG. 1 is
implemented as essentially Y-shaped and arching away from the
piston 4 and is exclusively used for clamping the components 8, 9
to the valve plate 2. The clamping element 7 is fastened to the
valve plate 2 using screws 11. The screws 11 are also used for
fastening the valve plate 2 to the cylinder housing 1.
[0074] FIG. 4 shows the cylinder head described up to this point
having clamping element 7 and valve plate 2 partially in section.
One clamping section 7a of the clamping element 7 presses against a
section of the component 8 forming the pressure channel, by which
this is pressed against the valve plate 2 or more precisely against
the valve plate via the pressure contact edge 13.
[0075] FIG. 5 shows a view of the cylinder head in the direction of
the crankshaft axis. The construction of the cylinder head
according to the present invention may be recognized very well, in
particular the clamping element 7, the valve plate 2, and the
cylinder housing 1, all three of which are connected to one another
via the screws 11.
[0076] FIG. 6 shows a section along lines AA from FIG. 2. The
component 8 according to the present invention, which forms the
pressure channel and completely envelops it, is very well
recognizable. The clamping element 7, whose section 7a clamps the
component 8 at its end area 8c in the form of the pressure contact
edge 13 against the valve plate 2, is also very well recognizable.
In this view, the distance Z which is implemented between the
further section 8b of the component 8 and the valve plate 2 and
prevents a heat transfer from the pressure channel 8 containing the
compressed, hot refrigerant to the valve plate 2 and thus further
into the cylinder interior 12 and/or into the suction channel 9,
which is not visible in the sectional view, is also very well
recognizable in this view. In contrast to typical cylinder heads,
the compressed refrigerant is guided away from the valve plate in
the first section 8a of the pressure channel 8 and then guided away
from the cylinder housing 1 at a distance Z in the radial direction
in relation to the cylinder hole, without the compressed
refrigerant having further contact with the valve plate 2.
[0077] FIG. 7 shows a view of the cylinder head in the direction of
the crankshaft axis, like FIG. 5, but without clamping element 7,
so that the component 8 forming the pressure channel is very well
recognizable, as is the distance Z between the component 8 and the
valve plate 2.
[0078] FIG. 8 and FIG. 8a both show the end section of the section
8a of the component 8 forming the pressure channel, which is
tightly connected to the valve plate 2, which is not visible in
these figures, via the pressure contact edge 13. This end section
adjoining and thus connected to the valve plate 2 forms a pressure
chamber 8a according to the present invention to prevent excess
pressures during expulsion of the refrigerant from the cylinder.
The section 8a is also provided with receptacle devices 19 in the
form of pins, in which an end section of a pressure valve 15 may be
suspended. The pressure valve 15 is implemented in a way known per
se as a leaf spring element. The end section which may be suspended
in the receptacle devices is used as a fixed fastening section,
while in contrast the free end section 15a diametrically opposite
this end section alternately releases or closes the pressure hole
10 situated directly behind it in the valve plate 2 as a function
of the compression cycle. The component 8 according to the present
invention is also provided with an opening boundary 26 in the form
of a stop, as is obvious from FIG. 8a. This opening boundary is
used for delimiting the opening path of the pressure valve 15.
[0079] The configuration of the pressure valve 15 in the component
8 according to the present invention allows the pre-manufacturing
of these two parts along a separate manufacturing line. Component 8
including pressure valve 15 and opening boundary 26 may be rapidly
and easily connected to valve plate 2 using clamping element 7. The
typical type of fastening of the pressure valve 15 to the valve
plate 2 by rivets, for example, is no longer necessary, which
results in significant simplification and above all acceleration of
the manufacturing process.
[0080] FIG. 9 shows an alternative embodiment variant of a cylinder
head, in which in addition to the components 8, 9 forming the
pressure and suction channels, the valve plate 2 is also fastened
via a clamping element 7 having the clamping sections 7a and 7b to
the cylinder housing 1. The embodiment variant of a cylinder head
disclosed in FIG. 9 thus manages entirely without screws. In other
words, the entire cylinder head is solely clamped.
[0081] FIG. 10 shows a sectional view of the alternative embodiment
variant from FIG. 9, the distance Z inhibiting the heat transfer
between pressure channel 8 and valve plate 2 and/or between suction
channel 9 and valve plate 2 being very clearly visible. In this
case, the clamping element 7 comprises a clamping section 7b, which
encloses the valve plate 2 in its edge area around its entire
circumference and engages on an undercut 27 on the cylinder housing
1 in this exemplary embodiment, as is also clearly recognizable in
the detail view in FIG. 11. The clearance volume seal 14, which is
situated between valve plate 2 and cylinder housing 1, as well as
the suction valve 32, are also clearly recognizable in FIG. 11.
[0082] The clamping element 7 has an additional clamping section
7a, which is implemented as essentially U-shaped and clamps the
components 8, 9 to the valve plate 2.
[0083] FIG. 12 shows a section along plane A from FIG. 9. In this
view, the one-piece nature of the clamping element 7 having the
clamping sections 7a and 7b may be recognized very clearly. In
addition, the transition of the component 8 forming the pressure
channel into the pressure hole 10 is shown. The component 8
according to the present invention is tightly connected along the
pressure contact edge 13 to the valve plate 2. The pressure hole
10, as well as the mobile part of the pressure valve 15, is located
inside the area enclosed by the pressure contact edge 13. The area
enclosed by the pressure contact edge 13 is simultaneously the
single section of the valve plate 2 which comes into contact with
the compressed refrigerant from the cylinder.
[0084] This is also true, of course, for the suction contact edge
17, along which the suction channel 9 is tightly connected to the
valve plate 2. The suction hole 16 is located inside the area
enclosed by the suction contact edge 17. The area enclosed by the
suction contact edge 17 is simultaneously the single section of the
valve plate 2 which comes into contact with the refrigerant
suctioned into the cylinder.
[0085] The cylinder housing 1 has a shoulder 27, in which the valve
plate 2 is at least partially, but preferably entirely countersunk,
by which positioning of the valve plate 2 is simultaneously
achieved.
[0086] FIG. 13 and FIG. 14 both show a further alternative
embodiment variant of the cylinder head. However, the clamping
element 7 is implemented as divided in the area of its clamping
section 7a, so that each component 8, 9 has a clamping element 7
assigned thereto.
[0087] FIG. 15 and FIG. 16 both show an additional embodiment
variant of a cylinder head having an alternatively implemented
clamping element 7. The clamping section 7b of the clamping element
7 does not enclose the valve plate 2 around its entire
circumference in the edge area, but rather is implemented as
interrupted in this case, the interruptions forming openings in
this clamping section, by which the components 8, 9 are led away
from the cylinder head or toward the cylinder head, so that
actually multiple clamping sections 7b are provided. However, the
individual clamping sections 7b engage on an undercut 27 on the
cylinder housing 1 in the same way as already noted for the
exemplary embodiments listed above. The clamping section 7a is
implemented in a cross shape in this exemplary embodiment, one arm
of this cross passing into each clamping section 7b. The area in
which the individual arms of the cross meet is implemented as
cylindrical and causes the clamping of the components 8, 9.
[0088] FIG. 17 and FIG. 18 show another alternative embodiment
variant of the cylinder head, in which the clamping element 7
clamps both the components 8, 9 and also the valve plate 2 to the
cylinder housing 1. In this case, the cylinder housing 1 is
implemented as laterally raised, the raised section 1a having an
undercut, however, in which the clamping section 7b of the clamping
element 7 may engage. The valve plate 2, which terminates the
cylinder housing 1 on its front face and whose sections 1a project
axially beyond it, is clamped to the cylinder housing 1 in this
case by the clamping sections 7b, which are engaged with the
undercut of the section 1a. The clamping section 7a, which again
forms the clamping element 7 in one piece with the clamping section
7b, clamps the components 8, 9 to the valve plate 2. The raised
section 1a is provided with openings 18, through which the
components 8, 9 are led away from the cylinder head or toward the
cylinder head.
[0089] FIGS. 19 and 20 each show a sectional view of cylinder heads
according to the present invention, in which on one hand an O-ring
seal 20 and on the other hand a paper seal 21 are used for sealing
the connection of the suction channel 9 and/or also the pressure
channel 8 to the valve plate 2. This type of seal is already known
from the prior art, but therein the connection of the valve plate
to the cylinder cover is sealed, which is no longer necessary in a
cylinder head.
[0090] FIG. 21 shows an alternative embodiment variant of a
possible seal of the connection of pressure channel 8 or suction
channel 9 to the valve plate 2 on the basis of an additional,
further embodiment variant of a cylinder head according to the
present invention. The valve plate 2 is provided with a sealing
bead 23 as a sealing system here, in which a sealing projection 22
(see also FIGS. 8 and 8a), which is situated on the pressure
contact edge 13 of the component 8 forming the pressure channel
and/or on the suction contact edge of the component 9 forming the
suction channel, and which essentially corresponds to the outline
of the sealing bead 23 on the valve plate 2, engages
[0091] Of course, a reverse implementation is also conceivable,
i.e., a sealing bead 23 is provided on the pressure contact edge 13
of the component 8 forming the pressure channel and/or on the
suction contact edge 17 of the component 9 forming the suction
channel (see also FIGS. 8 and 8a), in which a sealing projection
22, which is situated on the valve plate 2 and corresponds to the
outline of the sealing bead 23, engages.
[0092] To ensure a seal of the connection, the sealing projection
22 must either have a larger volume than the sealing bead 23 or the
shape of the sealing projection 22 must be different from that of
the sealing bead 23. The compression forces applied during assembly
of the cylinder head, in particular also the clamping forces of the
clamping element 7, cause the sealing projection 22 to flow into
the sealing bead 23 and/or parts of the sealing projection 22
because of the high local surface pressure.
[0093] The implementation of the sealing bead 23 in connection with
the sealing projections 22 causes significantly less contact
pressure to be required between pressure or suction channel 8, 9
and valve plate 2 than is required between cylinder cover and valve
plate 2 in known cylinder heads for the same tightness. The
required surface pressure is the same in both systems, but the seal
areas differ greatly, however, namely a long wide seal in the case
of the paper seal and a short narrow seal area in the case of the
system of sealing bead 23--sealing projection 22.
[0094] The sealing system functions independently of the material
pairs used. Thus, for example, typical material pairs are possible,
such as metal (valve plate 2)--metal (components 8, 9) or also
metal (valve plate 2)--flowable plastic (components 8, 9) or
plastic (valve plate 2)--flowable plastic (components 8, 9).
[0095] The surface pressure required for the present application
may be specified as 5 to 20 N/mm.sup.2. An especially preferred
geometric shape of the sealing bead 23 is the V-shape or U-shape as
shown in FIGS. 24 through 31, that of the sealing projection 23 is
the pin shape, the free end of the sealing projection preferably
being implemented as flattened and/or rounded.
[0096] FIG. 24 shows a simple design of the sealing system having
V-shaped sealing bead 23 and pin-shaped sealing projection 22.
[0097] FIG. 25 shows a sealing bead 23 formed by two projecting
ribs on the valve plate 2, which works together with a pin-shaped
sealing projection 22.
[0098] In both cases, the pin-shaped sealing projection 22 is
implemented as flattened on its free end.
[0099] In FIG. 26, two pin-shaped sealing projections 22 are
provided on the pressure channel 8, which delimit a V-shaped
sealing bead 23, in which the pin-shaped sealing projection 22
situated on the valve plate 2 engages. In addition, sealing beads
23 are also situated on the valve plate 2, in which the two sealing
projections 22 situated on the pressure channel 8 engage, so that a
type of meshing occurs between the components 8, 9 forming the
pressure channel and the suction channel and the valve plate 2. The
pin-shaped sealing projections 22 are provided with a bevel on
their free end area.
[0100] FIGS. 27 through 31 show refinements of the sealing system
just described, the pin-shaped sealing projections 22 also being
implemented as rounded on their free end area.
[0101] The sealing system according to the present invention may be
used both in cylinder heads according to the present invention
described in this application and also in cylinder heads according
to the prior art, i.e., using cylinder covers. In the latter case,
the cylinder cover has the sealing projection 22 or the sealing
bead 23 and the valve plate 2 has the corresponding
counterpart.
[0102] FIGS. 22 and 23 show further views of the additional further
embodiment variants of the cylinder head from FIG. 21.
[0103] FIGS. 32 through 35 show an additional alternative
embodiment variant of a cylinder head having the components 8, 9.
The valve plate 2 is covered, with the exception of the suction or
pressure hole 16, 10, by a plastic sheath 25, which has a section
facing away from the cylinder housing 1 and a section facing toward
the cylinder housing. The components 8, 9 forming the pressure and
suction channels are integrated in the plastic layer 25, i.e., they
also comprise plastic.
[0104] The production is performed in multiple steps in this
case.
[0105] Firstly, the valve plate 2 is extrusion coated using plastic
25 (insert technology), pins 28, which are used for location
positioning of the pressure valve 15 (corresponding to the
receptacle devices 19), also already being injected on the side of
the valve plate 2 facing away from the cylinder housing 1.
[0106] The side facing away from the piston 4 is extrusion coated
flat. No retention devices for the suction valve are required here.
Only an exposed area for the location positioning of the suction
valve is to be provided. The suction valve itself is clamped
between the front face of the cylinder housing 1 and valve plate
2.
[0107] In a further step, to connect the component 8 forming the
pressure channel and the component 9 forming the suction channel,
which are also produced from plastic in a separate work step, to
the valve plate 2 along the sealing beads 24, whose outline
corresponds to the pressure contact edge 13 or suction contact edge
17 and which are not situated in the valve plate 2 in this
exemplary embodiment, but rather in the plastic sheath 25 enclosing
the valve plate 2, laser welding or vibration welding of the
plastic parts is performed.
[0108] The valve plate 2 is fastened to the cylinder housing 1
using clamping element 7, as in the prior embodiment variants.
[0109] FIGS. 36 and 37 show an embodiment variant of the cylinder
head in which a further clamping element 29 is provided in addition
to clamping element 7. This further clamping element is fastened to
clamping element 7 and/or engaged therewith according to the
present invention. A plate-shaped element 30, preferably made of
metal, forming the pressure valve 15 is provided on the valve plate
2 in this case, which is clamped to the valve plate 2 by the
clamping element 7. The opening boundary 26 for the pressure valve
15 is integrated in the component 8 as already shown in FIG. 21 or
35.
[0110] The components 8, 9 are manufactured in this case as a
one-piece plastic part.
[0111] In the embodiment variant shown in FIG. 38, the components
8, 9 are glued to the valve plate 2, the pressure valve 15 being
situated in the component 8 in this case, as already described
above.
[0112] FIG. 39 shows the orientation of the pressure valve 15 as a
leaf spring in relation to the valve plate 2, the components 8, 9
having been left out to clarify the readability of the figure.
* * * * *