GB2320552A - A combined bypass and thermostat assembly - Google Patents
A combined bypass and thermostat assembly Download PDFInfo
- Publication number
- GB2320552A GB2320552A GB9720631A GB9720631A GB2320552A GB 2320552 A GB2320552 A GB 2320552A GB 9720631 A GB9720631 A GB 9720631A GB 9720631 A GB9720631 A GB 9720631A GB 2320552 A GB2320552 A GB 2320552A
- Authority
- GB
- United Kingdom
- Prior art keywords
- bypass
- valve
- fluid
- assembly
- thermostat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/01—Control of temperature without auxiliary power
- G05D23/13—Control of temperature without auxiliary power by varying the mixing ratio of two fluids having different temperatures
- G05D23/1306—Control of temperature without auxiliary power by varying the mixing ratio of two fluids having different temperatures for liquids
- G05D23/132—Control of temperature without auxiliary power by varying the mixing ratio of two fluids having different temperatures for liquids with temperature sensing element
- G05D23/1333—Control of temperature without auxiliary power by varying the mixing ratio of two fluids having different temperatures for liquids with temperature sensing element measuring the temperature of incoming fluid
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
- F01P7/00—Controlling of coolant flow
- F01P7/14—Controlling of coolant flow the coolant being liquid
- F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
Abstract
A cooling circuit for an internal combustion engine 11 is disclosed in which the bypass and thermostat assembly 14 includes a first inlet passage 27, a second inlet passage or bypass flow passage 26A and a fluid outlet passage 26B. The first inlet passage 27 and the fluid outlet passage 26B being coaxially arranged so that fluid is able to follow a substantially straight flow path between the first inlet passage 27 and the outlet passage 26B.
Description
A C^.4BINED SS and THERMOSTAT zSS7MELV This invention relates to a thermosta: assembly and in particular to a thermostat assembly for a cooling circuit of an internal combustion engine.
It is well known to provide a thermostat assembly for the cooling circuit of an internal combustion engine to restrict the flow of cooling water through the radiator when the engine is started from cold.
It has become increasingly popular in recent years as disclosed in DE-A-1600704 to use a combined bypass and thermostat assembly located in the supply between the bottom of the radiator and the circulation pump rather than in the return between the engine and the top of the radiator.
It is an object of the invention to provide an improved combined bypass and thermostat assembly.
According to a first aspect of the invention there is provided a combined bypass and thermostat assembly for a cooling circuit of an internal combustion engine comprising a housing defining a valve chamber and a bypass and thermostat valve assembly mounted in the valve chamber, the housing having a first fluid inlet to connect the valve chamber to a source of cooled fluid, a second fluid inlet .o connect the valve chamber to a bypass flow from the engine and a fluid outlet to connect the valve chamber .s a return supply to the engine, the bypass and thermostat valve assembly having a temperature responsive valve actuating means connected to a first valve member to regulate the flow of fluid from the first inlet to said outlet in response to the sensed temperature of the fluid in contact with a temperature sensitive part of said temperature responsive valve actuating means and a second valve member to regulate the flow of fluid from said second inlet to said outlet wherein said first inlet passage and said fluid outlet are coaxially arranged such that upon full opening of the first valve member fluid is able to follow a substantially straight flow path from said first inlet passage to said fluid outlet.
The second fluid Inlet may be arranged at an acute angle with respect to said fluid outlet.
The temperature sensitive portion may be a wax filled temperature responsive actuator having a reaction rod extending therefrom for reaction against an abutment formed within the first inlet passage.
The housing may be comprised of two separate housing parts connected together to define the valve chamber.
The bypass and thermostat valve assembly may have a flange plate which is clamped between the two housing parts at their ,ancture so as to secure the bypass and thermostat assembly within the valve chamber.
The first valve member may be biased towards a closed position by a spring acting between the first valve member and a reaction plate connected to the flange plate.
Advantageously, the first valve member may be biased towards a closed position by a spring acting between the first valve member and an abutment surface formed as part of the housing.
Advantageously, the first valve member may be biased towards an annular lip formed as an integral part of the housing by a spring.
The two housing parts may be made from a plastics material.
According to a second aspect of the invention there is provided a cooling circuit for an internal combustion engine comprising a radiator having a top tank and a bottom tank, a combined bypass and thermostat assembly interposed in the supply between the bottom tank and the engine, a coolant circulation pump to circulate coolant through the engine and return it via a return line to the radiator and a bypass line connected between the return line and the combined bypass and thermostat assembly to allow a controlled flow of coolant from the return line to pass back into the engine wherein the bypass and thermostat assembly comprises of a housing defining a valve chamber and a bypass and thermostat valve assembly mounted in the valve chamber, the housing having a first fluid inlet to connect the valve chamber to a supply line from the bottom of the radiator, a second fluid inlet to connect the valve chamber to the bypass line and a fluid outlet to connect the valve chamber to the engine, the bypass and thermostat valve assembly having a temperature responsive valve actuating means connected to a first valve member to regulate the flow of fluid from the first inlet to said outlet in response to the sensed temperature of the fluid in contact with a temperature sensitive part of said temperature responsive valve actuating means and a second valve member to regulate the flow of fluid from said second inlet to said outlet, wherein said first inlet passage and said fluid outlet are coaxially arranged such that upon full opening of the first valve member fluid is able to follow a substantiaily straight flow path from said first inlet passage to said fluid outlet.
The second fluid inlet may be arranged at an acute angle with respect to said fluid outlet.
The temperature sensitive portion may be a wax filled temperature responsive actuator having a reaction rod extending therefrom for reaction against an abutment formed within the first inlet passage.
The housing may be comprised of two separate housing parts connected together to define the valve chamber.
The invention will now be described with reference to the accompanying drawing of which:
Fig.1: is a cross section through a combined bypass
and thermostat assembly according to a first
embodiment of the invention showing a
thermostat valve and a bypass valve both in a
closed position;
Fig.2: is a schematic drawing of a cooling circuit
for an internal combustion engine
incorporating a combined bypass and thermostat
according to the invention; and
Fig.3 is a cross section through a combined bypass
and thermostat assembly according to a second
embodiment of the invention showing a
thermostat valve and a bypass valve both in a
closed position
With reference to Figure 2 there is shown an engine 11 having a coolant circulation pump 12, a radiator 13 having a top tank 16 and a bottom tank 17 and a combined bypass and thermostat assembly 14 interposed in the supply line between the bottom tank 17 and the coolant circulation pump 12.
The bypass and thermostat assembly 14 is connected to the bottom tank 17 of the radiator 13 by means of a bottom hose 18 and to the circulation pump 12 by means of a supply hose 15. The bypass and thermostat assembly is further connected to a top or return hose 10 connecting the engine 11 to the top tank 16 of the radiator 13 by means of a bypass hose 22.
In use the cooling circuit operates as follows, initially, when the engine is cold, the thermostat part of the assembly 14 is in a closed position preventing the passage of coolant from the bottom tank 17 into the engine 11 via the bottom hose 18 and the supply hose 15.
To prevent local overheating of the engine 11 when the thermostat valve is closed the bypass valve part of the assembly is open allowing a controlled flow of coolant from the return hose ;0 through the bypass passage 22 to the supply hose 15.
When the temperature of the coolant passing through the bypass and thermostat assembly 14 reaches a predetermined temperature the thermostat part of the assembly 14 is operative to allow coolant to gradually be admitted from the bottom tank i7 through the bottom hose 18 to mix with the coolant already circulating through the engine 11.
When the engine is at its normal running temperature, coolant passes freely from the bottom tank 17 through the bypass and thermostat assembly 14 and into the circulation pump 12, through cooling passages (not shown) defined within the engine 11 and then back to the top tank 16 via the return hose 10 to be cooled for recirculation from the bottom tank 17.
As the temperature of the coolant approaches the normal running temperature the bypass valve part of the assembly closes so that flow through the bypass hose 22 is effectively shut off ensuring that virtually all of the coolant circulates through the radiator 13 before returning to the engine 11.
With particular reference to Fig 1 there is shown in greater detail the combined bypass and thermostat assembly 14.
The assembly comprises of first and second plastic housings 25,26 secured together by friction welding defining a valve chamber 20 in which is mounted a combined bypass and thermostat valve assembly 30.
The first plastic housing in the form of a tubular inlet member 25 has a cylindrical outer surface 25A for engagement with the bottom hose 18 and an internal surface which defines a first inlet passage 27 and part of the valve chamber 20.
The second plastic housing 26 has an internal cavity which defines the major portion of the valve chamber 20, a first cylindrical portion defining a second inlet passage 26A to connect the bypass hose 22 to the valve chamber 20 and a second cylindrical portion defining a fluid outlet passage 26B to connect the valve chamber 20 to the supply hose 15. The first inlet passage 27 and the fluid outlet passage 26B are on a common axis whereas the axis of the outlet means 26B is inclined at an acute angle with respect to the axis of the second inlet passage 26A.
The coaxial relationship between the first inlet passage 27 and the fluid outlet passage 26B allows fluid entering via the first inlet passage 27 to follow a substantially straight flow path to the outlet passage 26B. This considerably reduces the flow losses through the bypass and thermostat assembly when the valve is fully open compared to a prior art assembly as referred to above.
The bypass and thermostat valve assembly 30 is conventional in construction and comprises of a temperature responsive valve actuating means 31 formed by a temperature sensitive portion in the form of a wax filled body 32, an end cap 35 and a reaction rod 33.
The reaction rod 33 extends away from the wax filled body 32 towards the first inlet passage 27 where it reacts against an abutment 34 formed on the wall of the first inlet passage 27.
A first valve member 36 is attached to the end cap 35 and the wax filled body 32 near to the end from which extends the reaction rod 33. The first valve member 36 extends radially outwardly from the wax filled body 32 for co-operation with an inwardly extending lip 40 formed on a flange plate 41 connected to a pair of longitudinally extending limbs 28A.
The first valve member 36 and the extending lip 40 forming in combination the thermostat valve part of the valve assembly 30 to regulate the flow of coolant from the first inlet passage 27 to the outlet passage 26B.
The first valve member 36 is biased towards the lip 40 against the action of the valve actuating means 31 by a spring 29 interposed between the first valve member 36 and a reaction plate 28 connected to the flange plate 41 by means of the pair of longitudinally extending limbs 28A.
The flange plate 41 is used to support and locate the valve assembly 30 within the valve chamber 20 and is clamped around its outer periphery between the first and second housings 25, 26. A sealing ring 42 is interposed between the first housing 25 and the flange plate 41 to provide a seal between the first and second housings 25,26.
At the end of the bypass and thermostat valve assembly 30 facing the second inlet passage 26A there is formed a spring biased second valve means in the form of a bypass flow valve 50. The bypass flow valve 50 has a valve member 51 for abutment against an end wall 52 of the second plastic housing 26 to regulate the flow of coolant from the second inlet 26A to the outlet passage 26B.
extended causing the first valve member 36 to be fully open and the bypass flow valve 50 is closed thereby restricting the flow of coolant passing between the second inlet 26A and the outlet 26B.
The closing of the bypass valve 50 ensures that the majority of the coolant passes through the radiator 13 before being returned to the engine 11 via the combined bypass and thermostat assembly thereby achieving maximum cooling particularly as the flow from the radiator 13 to the engine 11 is less restricted due to the geometry of the combined bypass and thermostat valve assembly.
With particular reference to Fig.3 there is shown a second embodiment of the invention which in most respects is the same as that previously described with reference to Fig.1.
Once again a first plastic housing 25 has a cylindrical outer surface 25A for engagement with the bottom hose 18 and has an internal bore which defines a first inlet passage 27 and part of a valve chamber 20.
A second plastic housing 26 has an internal cavity which defines the major portion of the valve chamber 20, a first cylindrical portion defining a second inlet passage 26A to connect the bypass hose 22 to the valve chamber 20 and a second cylindrical portion defining a fluid outlet passage 25B to connect the valve chamber 20 to the supply hose 15. The first inlet passage 27 and the fluid outlet passage 26B are on a common axis whereas the axis of the outlet means 26B is inclined at an acute angle with respect to the axis of the second inlet passage 26A.
The coaxial relationship between the first inlet passage 27 and the fluid outlet passage 26B allows fluid entering via the first inlet passage 27 to follow a substantially straight flow path to the outlet passage 26B. This considerably reduces the flow losses through the bypass and thermostat assembly when the valve is fully open compared to a prior art assembly as referred to above.
The bypass and thermostat valve assembly 30 comprises of a temperature responsive valve actuating means 31 formed by a temperature sensitive portion in the form of a wax filled body 32, an end cap 35 and a reaction rod 33.
The reaction rod 33 extends away from the wax filled body 32 towards the first inlet passage 27 where it reacts against an abutment 34 formed on the wall of the first inlet passage 27.
A first valve member 36 is attached to the end cap 35 and the wax filled body 32 near to the end from which extends the reaction rod 33. The first valve member 36 extends radially outwardly from the wax filled body 32 for co-operation with an inwardly extending annular lip 56 formed in the bore 27 of the first plastic housing 25.
The first valve member 36 and the extending lip 56 forming in combination the thermostat valve part of the valve assembly 30 to regulate the flow of coolant from the first inlet passage 27 to the outlet passage 26B.
The first valve member 36 is biased towards the lip 56 against the action of the valve actuating means 31 by a spring 29 interposed between the first valve member 36 and an end wall 52 of the second plastic housing 26.
At the end of the bypass and thermostat valve assembly 30 facing the second inlet passage 26A there is formed a spring biased second valve means in the form of a bypass flow valve having a valve member 51 for abutment against the end wall 52 of the second plastic housing 26 to regulate the flow of coolant from the second inlet 26A to the outlet passage 26B.
The diameter of the spring 29 is such that it extends over the valve member 51 with clearance for direct reaction against the end wall 52.
This embodiment has the advantage that because the spring 29 acts directly between an abutment formed by one of the housings and the valve member 36 the construction of the assembly is simplyfied and the use of an integral lip 56 against which the valve 36 can seal further simplyfies the construction and in addition reduces the number of components that can impede or restrict the flow of fluid through the assembly.
As previously described when the engine 11 has reached its normal running temperature the reaction rod 33 is virtually fully extended causing the first valve member 36 to be fully open and the bypass flow valve 51 is closed thereby restricting the flow of coolant passing between the second inlet 26A and the outlet 26B.
The closing of the bypass valve 51 ensures that the majority of the coolant passes through the radiator 13 before being returned to the engine 11 via the combined bypass and thermostat assembly thereby achieving maximum cooling particularly as the flow from the radiator 13 to the engine 11 is less restricted due to the geometry of the combined bypass and thermostat valve assembly.
However in this case there is no reaction plate the spring acting directly against the inner wall of the second plastic housing. In addition the valve 36 bears directly against the wall of the first plastic housing 25.
Furthermore it will be appreciated that the invention is not limited to the embodiments specifically described herein for example the first and second housings could be made of any suitable material and the bypass and thermostat assembly could be incorporated into the housing of another component forming part of the cooling circuit such as the circulation pump or part of the radiator.
Claims (15)
1. A combined bypass and thermostat assembly for a cooling
circuit of an internal combustion engine comprising a
housing defining a valve chamber and a bypass and
thermostat valve assembly mounted in the valve chamber,
the housing having a first fluid inlet to connect the
valve chamber to a source of cooled fluid, a second
fluid inlet to connect the valve chamber to a bypass
flow from the engine and a fluid outlet to connect the
valve chamber to a return supply to the engine, the
bypass and -hermostat valve assembly having a
temperature responsive valve actuating means connected
to a first valve member to regulate the flow of fluid
from the first inlet to said outlet in response to the
sensed temperature of the fluid in contact with a
temperature sensitive part of said temperature
responsive valve actuating means and a second valve
member to regulate the flow of fluid from said second
inlet to said outlet wherein said first inlet passage
and said fluid outlet are coaxially arranged such that
upon full opening of the first valve member fluid is
able to follow a substantially straight flow path from
said first inlet passage to said fluid outlet.
2. A bypass and thermostat assembly is claimed in Claim 1
in which the second fluid inlet is arranged at an acute
angle with respect to said fluid outlet.
3. A bypass and thermostat assembly as claimed in any
preceding Claim in which the temperature sensitive
portion is a wax filled temperature responsive actuator
having a reaction rod extending therefrom for reaction
against an abutment formed within the first inlet
passage.
4. A bypass and thermostat assembly as claimed in any
preceding claim in which the housing is comprised of
two separate housing parts connected together to define
the valve chamber.
5. A bypass and thermostat assembly as claimed in Claim 4
in which the bypass and thermostat valve assembly has a
flange plate which is clamped between the two housing
parts at their juncture so as to secure the bypass and
thermostat assembly within the valve chamber.
6. A bypass and thermostat assembly as claimed in Claim 4
or in Claim 5 claim in which the first valve member is
biased towards a closed position by a spring acting
between the first valve member and a reaction plate
connected to the flange plate.
7. A bypass and thermostat assembly as claimed in any of
Claims 1 to 4 in which the first valve member is biased
towards a closed position by a spring acting between
the first valve member and an abutment surface formed
as part of the housing.
8. A bypass and thermostat assembly as claimed in any of
Claims 1 to 4 or in Claim 7 in which the first valve
member is biased. towards an annular lip formed as an
integral part tf the housing by a spring.
9. A bypass and thermostat assembly as claimed in Claim 4
in which the two housing parts are made from a plastics
material.
10.A cooling circuit for an internal combustion engine
comprising a radiator having a top tank and a bottom
tank, a combined bypass and thermostat assembly
interposed in the supply between the bottom tank and
the engine, a coolant circulation pump to circulate
coolant through the engine and return it via a return
line to the radiator and a bypass line connected
between the return line and the combined bypass and
thermostat assembly to allow a controlled flow of
coolant from the return line to pass back into the
engine wherein said first inlet passage and said fluid
outlet are coaxially arranged such that upon full
opening of the first valve member fluid is able to
follow a substantially straight flow path from said
first inlet passage to said fluid outlet.
ll.A cooling circuit as claimed in claim 10 in which the
second fluid inlet is arranged at an acute angle with
respect to said fluid outlet.
12.A cooling circuit as claimed in Claim 10 or in Claim 11
in which the temperature sensitive portion is a wax
filled temperature responsive actuator having a
reaction rod extending therefrom for reaction against
an abutment formed within the first inlet passage.
13. A cooling circuit as claimed in any of Claims 10 to 12
in which the housing is comprised of two separate
housing parts connected together to define the valve
chamber.
14.A cooling circuit for an internal combustion engine
substantially as described herein with reference to the
accompanying drawing.
15. A combined bypass and thermostat assembly substantially
as described herein with reference to the accompanying
drawing.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB9626047.6A GB9626047D0 (en) | 1996-12-14 | 1996-12-14 | A combined bypass and thermostat assembly |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9720631D0 GB9720631D0 (en) | 1997-11-26 |
| GB2320552A true GB2320552A (en) | 1998-06-24 |
| GB2320552B GB2320552B (en) | 2000-08-02 |
Family
ID=10804492
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB9626047.6A Pending GB9626047D0 (en) | 1996-12-14 | 1996-12-14 | A combined bypass and thermostat assembly |
| GB9720631A Expired - Fee Related GB2320552B (en) | 1996-12-14 | 1997-09-30 | A combined bypass and thermostat assembly |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB9626047.6A Pending GB9626047D0 (en) | 1996-12-14 | 1996-12-14 | A combined bypass and thermostat assembly |
Country Status (1)
| Country | Link |
|---|---|
| GB (2) | GB9626047D0 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7069880B2 (en) | 2002-09-04 | 2006-07-04 | Ford Global Technologies, Llc | Engine cooling systems |
| DE102009042496A1 (en) * | 2009-09-15 | 2011-03-24 | Behr Thermot-Tronik Gmbh | Multi-way valve with low pressure loss |
| DE102013111048A1 (en) * | 2013-10-07 | 2015-04-09 | Gustav Wahler Gmbh U. Co. Kg | Thermostatic valve and method of making such |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2290123A (en) * | 1994-06-09 | 1995-12-13 | Rover Group | A combined bypass and thermostat assembly |
-
1996
- 1996-12-14 GB GBGB9626047.6A patent/GB9626047D0/en active Pending
-
1997
- 1997-09-30 GB GB9720631A patent/GB2320552B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2290123A (en) * | 1994-06-09 | 1995-12-13 | Rover Group | A combined bypass and thermostat assembly |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7069880B2 (en) | 2002-09-04 | 2006-07-04 | Ford Global Technologies, Llc | Engine cooling systems |
| DE102009042496A1 (en) * | 2009-09-15 | 2011-03-24 | Behr Thermot-Tronik Gmbh | Multi-way valve with low pressure loss |
| EP2333269A3 (en) * | 2009-09-15 | 2014-01-08 | Behr Thermot-tronik GmbH | Multi-directional valve with low pressure loss |
| DE102013111048A1 (en) * | 2013-10-07 | 2015-04-09 | Gustav Wahler Gmbh U. Co. Kg | Thermostatic valve and method of making such |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9720631D0 (en) | 1997-11-26 |
| GB2320552B (en) | 2000-08-02 |
| GB9626047D0 (en) | 1997-01-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| 746 | Register noted 'licences of right' (sect. 46/1977) |
Effective date: 20050719 |
|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20070930 |