U.S. patent application number 11/887286 was filed with the patent office on 2009-05-28 for refrigerant compressor.
Invention is credited to Alfred Freiberger, Mathias Ponhold, Gunther Zippl.
Application Number | 20090136365 11/887286 |
Document ID | / |
Family ID | 36578775 |
Filed Date | 2009-05-28 |
United States Patent
Application |
20090136365 |
Kind Code |
A1 |
Zippl; Gunther ; et
al. |
May 28, 2009 |
Refrigerant Compressor
Abstract
The invention relates to a hermetically encapsulated
refrigeration compressor comprising a hermetically sealed
compressor housing containing a piston-cylinder unit compressing a
refrigerating agent. The cylinder is closed by means of a valve
plate comprising a pressure borehole and a suction borehole, and a
suction channel and a pressure channel are used to suck the
refrigerating agent into the suction borehole by means of a suction
valve, and to compress the refrigerating agent passing from the
pressure borehole into the pressure channel by means of a pressure
valve. Preferably, a suction sound absorber is arranged in the
suction channel. The aim of the invention is to create one such
refrigeration compressor that enables a significant decrease in the
suction temperature and the exhaust temperature. To this end, the
pressure channel is formed by a component that surrounds the entire
pressure channel and is connected to the valve plate in a sealed
manner along a pressure contact edge formed by an end section of
the component. The pressure borehole and the mobile part of the
pressure valve are arranged inside the surface surrounded by the
pressure contact edge.
Inventors: |
Zippl; Gunther; (Graz,
AT) ; Freiberger; Alfred; (Grosswilfersdorf, AT)
; Ponhold; Mathias; (Weiz, AT) |
Correspondence
Address: |
COLLARD & ROE, P.C.
1077 NORTHERN BOULEVARD
ROSLYN
NY
11576
US
|
Family ID: |
36578775 |
Appl. No.: |
11/887286 |
Filed: |
March 30, 2006 |
PCT Filed: |
March 30, 2006 |
PCT NO: |
PCT/EP2006/061198 |
371 Date: |
September 27, 2007 |
Current U.S.
Class: |
417/312 |
Current CPC
Class: |
F04B 39/123 20130101;
F04B 39/125 20130101; F04B 39/06 20130101 |
Class at
Publication: |
417/312 |
International
Class: |
F04B 39/00 20060101
F04B039/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2005 |
AT |
GM 195/2005 |
Apr 12, 2005 |
AT |
GM 223/2005 |
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 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), the pressure hole
(10) and the mobile part of the pressure valve (15) being situated
inside the area enclosed by the pressure contact edge (13).
2. The hermetically encapsulated refrigerant compressor according
to claim 1, 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.
3. 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 by
less than 50%.
4. 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.
5. The hermetically encapsulated refrigerant compressor according
to claim 1, 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.
6. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein an insulating material, preferably made of
rubber or plastic, is situated between the further section (8b) and
the valve plate (2).
7. 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.
8. 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.
9. 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.
10. The hermetically encapsulated refrigerant compressor according
to claim 9, wherein the pressure chamber (8a) is situated directly
adjoining the pressure hole (10) in the component (8) forming the
pressure channel.
11. 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.
12. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein the clamping element (18) has an essentially
J-shaped cross-section.
13. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein the clamping element (7) is implemented as
circular.
14. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein one or more undercuts (27), which may be
engaged with an end section of the clamping element (7), are
provided on the cylinder housing (1).
15. The hermetically encapsulated refrigerant compressor according
to claim 11, 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).
16. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein the cylinder housing has a shoulder (31), in
which the valve plate (16) is at least partially countersunk.
17. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein the surface of the valve plate (2) facing away
from the piston (4) terminates flush with the cylinder housing
(1).
18. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein the clamping element (7) has at least one
further clamping section (7a), which clamps the components (8, 9)
forming the pressure channel and the suction channel to the valve
plate (2) or in the suction hole (16) and/or the pressure, hole
(10).
19. The hermetically encapsulated refrigerant compressor according
to claim 11, wherein a further clamping element (29) is provided,
which may be engaged on the clamping element (7) and clamps the
components (8, 9) forming the pressure channel and the suction
channel to the valve plate (2) or in the suction hole (16) and/or
the pressure hole (10).
20. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein separate fasteners (11) are provided and/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 may be
engaged on the cylinder housing (3) and clamps the components (8,
9) forming the pressure channel respectively the suction channel to
the valve plate (2) or in the suction hole (16) and/or the pressure
hole (10).
23. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein preferably V-shaped sealing beads (23) are
provided in the valve plate (2), and the front face, facing toward
the valve plate (2), of the components (8, 9) forming the suction
channel and the pressure channel is equipped along its suction or
pressure contact edge (13, 17) with sealing projections (22)
essentially corresponding to the V-shaped sealing beads (23), the
sealing projections (22) being implemented as different in their
geometrical design from the sealing beads (23) and/or having a
different volume.
24. The hermetically encapsulated refrigerant compressor according
to claim 1, wherein sealing projections (22) are provided in the
valve plate (2), and the front face, facing toward the valve plate
(2) of the components (8, 9) forming the suction channel and the
pressure channel is equipped along its suction or pressure contact
edge (13, 17) with sealing beads (23) essentially corresponding to
the sealing projections (22), the sealing projections (22) being
implemented as different in their geometrical design from sealing
beads (23) and/or having a different volume.
Description
AREA OF THE INVENTION
[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, a suction noise damper preferably being situated
in the suction channel, according to the preamble of Claim 1.
[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] The known embodiment variant described has the disadvantage
that the refrigerant heats up too strongly on its way 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.
[0011] 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 variations 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 resulting in heating of the refrigerant at
beginning of the compression procedure may not occur. However, this
achievement of the object has the disadvantage that there is
usually a greater pressure drop during the suctioning, which
reduces the volumetric efficiency and thus the energy efficiency to
varying degrees.
[0012] 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.
[0013] 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.
[0014] 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.
[0015] A hermetically encapsulated compressor having a suction
housing situated on a base plate on the cylinder head and a
pressure housing separated therefrom is known from U.S. Pat. No.
5,288,212. The same base plate forms the shared floor of suction
and pressure housings and presses flat against the cylinder head
configuration.
DESCRIPTION OF THE INVENTION
[0016] It is therefore the object of the present invention to avoid
the described disadvantages and provide a refrigerant compressor of
the type cited at the beginning, which allows a significant
reduction of the suction temperature and the expulsion
temperature.
[0017] This is achieved according to the present invention by the
characterizing features of Claim 1.
[0018] By providing an independent component, which forms the
pressure channel and completely envelops it, and connecting this
component directly to the pressure hole, the pressure channel is
completely thermally separated from the valve plate. The components
according to the present invention 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 directly enclosing 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 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 be reduced, by which the intake temperature may
be decreased.
[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 2. It is necessary
on one hand for the pressure hole to lie inside this area and on
the other hand for the transition between pressure channel and
pressure flow to be implemented for favorable flow and nonetheless
allow a tight connection. Because according to the present
invention the pressure channel or more precisely the last section
of this channel is incident on the pressure hole and thus on the
valve plate essentially perpendicularly to prevent heat transfer
from the valve plate to the pressure channel and/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 greater than 1/12.
[0021] According to the characterizing features of Claim 4, 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 5, 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 6, 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 7, 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 8 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 7, pre-assembling of
pressure channel and pressure valve including suction channel.
[0026] According to the characterizing features of Claims 9 and 10,
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 11, 12,
and 13, the valve plate is fastened to the cylinder housing using 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 may be engaged at an end section on
undercuts provided on the cylinder housing according to the
characterizing features of Claim 14.
[0029] According to the characterizing features of Claim 15, the
valve plate is clamped to the cylinder housing using the other end
section, which forms a first clamping leg.
[0030] The cylinder housing is provided with a shoulder according
to the characterizing features of Claim 16, 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, a preferred embodiment variant
according to the characterizing features of Claim 17 providing that
the surface of the valve plate facing away from the piston
terminate 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 component forming the
pressure and/or suction channels are clamped to the valve plate,
thus, a combination of clamping and screwing.
[0034] The characterizing features of Claims 23 and 24 describe a
preferred embodiment variant of the sealed connection of the
components forming the suction and pressure channels 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. Implementing the sealing bead in connection with the
sealing projections results in a significantly lower required
compression force between pressure and/or suction channels and
valve plate than is the case between cylinder cover and valve plate
in known cylinder heads.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] In the following, the present invention is described in
greater detail on the basis of exemplary embodiments.
[0036] FIG. 1 shows an axonometric view of a piston-cylinder unit
including cylinder head according to the present invention
[0037] FIG. 2 shows a frontal view of a cylinder head according to
the present invention
[0038] FIG. 3 shows an axonometric view of a piston-cylinder head
including cylinder head according to the present invention without
clamping element
[0039] FIG. 4 shows an axonometric sectional detail view of a
cylinder head according to the present invention
[0040] FIG. 5 shows a view in the direction of the crankshaft axis
of a cylinder head including cylinder housing and crankcase
[0041] FIG. 6 shows a section along line AA from FIG. 2
[0042] FIG. 7 shows a view in the direction of the crankshaft axis
of a cylinder head including cylinder housing and crankcase without
clamping element
[0043] FIG. 8 shows an axonometric view of the component forming
the pressure channel
[0044] FIG. 8a shows an axonometric view of the component forming
the pressure channel in section
[0045] FIG. 9 shows an alternative embodiment variant of a cylinder
head according to the present invention
[0046] FIG. 10 shows a sectional view of the alternative embodiment
variation from FIG. 9 along plane A1 from FIG. 9
[0047] FIG. 11 shows a detail view from FIG. 10
[0048] FIG. 12 shows a sectional view along plane A from FIG. 9
[0049] FIG. 13 shows a further alternative embodiment variant of a
cylinder head according to the present invention
[0050] FIG. 14 shows a sectional view along plane B from FIG.
13
[0051] FIG. 15 shows an additional alternative embodiment variant
of a cylinder head according to the present invention
[0052] FIG. 16 shows a sectional view along plane C from FIG.
15
[0053] FIG. 17 shows another alternative embodiment variant of a
cylinder head according to the present invention
[0054] FIG. 18 shows a sectional view along plane D from FIG.
17
[0055] FIG. 19 shows a sectional view of a cylinder head according
to the present invention having O-ring seal
[0056] FIG. 20 shows a sectional view of a cylinder head according
to the present invention having paper seal
[0057] FIG. 21 shows an illustration of an alternative sealing
system in section along plane E from FIG. 22
[0058] FIG. 22 shows an additional further embodiment variant of a
cylinder head according to the present invention from FIG. 21
[0059] FIG. 23 shows a sectional view along plane F from FIG.
22
[0060] FIG. 24-31 show sectional views of an alternative sealing
system
[0061] FIG. 32 shows an additional, alternative embodiment variant
of a cylinder head according to the present invention
[0062] FIG. 33 shows a sectional view along plane G from FIG.
32
[0063] FIG. 34 shows a top view of a cylinder head from FIG. 32
[0064] FIG. 35 shows a sectional view along plane H from FIG.
34
[0065] FIG. 36 shows a further exemplary embodiment of a cylinder
head according to the present invention
[0066] FIG. 37 shows an axonometric view of the cylinder housing
including clamping element from FIG. 36
[0067] FIG. 38 shows a further exemplary embodiment of a cylinder
head according to the present invention
[0068] FIG. 39 shows the exemplary embodiment from FIG. 38 without
the components forming the pressure and suction channels.
WAYS OF IMPLEMENTING THE INVENTION
[0069] FIG. 1 shows an axonometric view of a cylinder head
according to the present invention, sections of the cylinder
housing 1, the valve plate 2, and the suction noise damper 3
including intake opening 3a being visible.
[0070] 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.
[0071] FIG. 1 and FIG. 2 show an embodiment variant of a cylinder
head according to the present invention in the completely assembled
state, i.e., having a clamping element 7, while in contrast FIG. 3
shows the same cylinder head according to the present invention 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).
[0072] 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.
[0073] 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.
[0074] 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.
[0075] FIG. 4 shows the cylinder head according to the present
invention 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.
[0076] FIG. 5 shows a view of the cylinder head according to the
present invention 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.
[0077] 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.
[0078] 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.
[0079] 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.
[0080] 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.
[0081] FIG. 9 shows an alternative embodiment variant of a cylinder
head according to the present invention, 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 according to the present
invention disclosed in FIG. 9 thus manages entirely without screws.
In other words, the entire cylinder head is solely clamped.
[0082] 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.
[0083] 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.
[0084] 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.
[0085] 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.
[0086] 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.
[0087] FIG. 13 and FIG. 14 both show a further alternative
embodiment variant of the cylinder head according to the present
invention. 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.
[0088] FIG. 15 and FIG. 16 both show an additional embodiment
variant of a cylinder head according to the present invention
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.
[0089] FIG. 17 and FIG. 18 show another alternative embodiment
variant of the cylinder head according to the present invention, 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.
[0090] 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 according to the present invention.
[0091] 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 17 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.
[0092] 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.
[0093] 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.
[0094] 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.
[0095] 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).
[0096] 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.
[0097] FIG. 24 shows a simple design of the sealing system having
V-shaped sealing bead 23 and pin-shaped sealing projection 22.
[0098] 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.
[0099] In both cases, the pin-shaped sealing projection 22 is
implemented as flattened on its free end.
[0100] 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.
[0101] 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.
[0102] 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.
[0103] FIGS. 22 and 23 show further views of the additional further
embodiment variants of the cylinder head according to the present
invention from FIG. 21.
[0104] FIGS. 32 through 35 show an additional alternative
embodiment variant of a cylinder head according to the present
invention 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.
[0105] The production is performed in multiple steps in this
case.
[0106] 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.
[0107] 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.
[0108] 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.
[0109] The valve plate 2 is fastened to the cylinder housing 1
using clamping element 7, as in the prior embodiment variants.
[0110] 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.
[0111] The components 8, 9 are manufactured in this case as a
one-piece plastic part.
[0112] 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.
[0113] 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.
LIST OF REFERENCE NUMERALS
[0114] 1. cylinder housing [0115] 1a. raised section of the
cylinder housing [0116] 2. valve plate [0117] 3. suction noise
damper [0118] 3a. intake opening [0119] 4. piston [0120] 5.
crankshaft bearing [0121] 5a. crankcase [0122] 6. cylinder axis
[0123] 7. clamping element [0124] 7a. clamping section [0125] 7b.
clamping section [0126] 8. component forming the pressure channel
[0127] 8a. section of the pressure channel leading away, pressure
chamber [0128] 8b. further section of the pressure channel [0129]
9. component forming the suction channel [0130] 10. pressure hole
[0131] 11. screws [0132] 12. cylinder interior [0133] 13. pressure
contact edge [0134] 14. clearance volume seal [0135] 15. pressure
valve [0136] 15a. free end section of the pressure valve [0137] 16.
suction hole [0138] 17. suction contact edge [0139] 18. openings
[0140] 19. receptacle devices [0141] 20. o-ring seal [0142] 21.
paper seal [0143] 22. sealing projection [0144] 23. sealing bead
[0145] 24. sealing bead [0146] 25. plastic sheath [0147] 26.
opening boundary [0148] 27. undercut [0149] 28. pins [0150] 29.
further clamping element [0151] 30. plate-shaped element [0152] 31.
shoulder [0153] 32. suction valve
* * * * *