DE9015766U1 - Thermostatic valve for regulating the temperature of the coolant of an internal combustion engine - Google Patents

Description

Patent Attorney Mülbergerstr. 65 Authorized representative at Dipl.-Ing. Volkhard Kratzsch D-7300 Esslingen European Patent Office Ti? ^! eifi<&Oacgr;&Ggr;1 Ii 31 22 48 European Patent Attorney Telephone Stuttgart (0711) 317000 Deutsche Bank Esslingen 210906 cable «krapatent» esslingenneckar Postgiroamt Stuttgart 10004-701

Gustav Wahler GmbH & Co

8 November 1990

7300 Esslingen

Attorney file 4993

Thermostat valve for regulating the temperature of the coolant of an internal combustion engine

The invention relates to a thermostat valve for regulating the temperature of the coolant of an internal combustion engine of the type mentioned in the preamble of claim 1.

In a known thermostatic valve of this type (DE-OS 37 05 232, DE-OS 33 15 30Θ), the actuator, which is coaxial with the temperature-dependent working element and is designed in particular as a temperature-dependent working element, is held in a bore on the valve housing. This holder has to absorb the axial support forces for the working piston of the temperature-dependent working element. Pure axial centering in a bore is usually not sufficient for this.

The invention is based on the object of designing a thermostat valve of the type mentioned at the beginning in such a way that the actuator is held reliably and firmly on the valve housing so that the actuator can be easily mounted and fastened on the one hand and on the other hand is able to absorb the axial support forces for the working piston of the thermostatic working element without changing the axial position of this actuator.

The problem is solved according to the invention in a thermostat valve of the type mentioned in the preamble of claim 1 by the features in the characterizing part of claim 1. Because the actuator is attached to the valve housing by a flange connection, the actuator can be attached quickly and easily and connected to the valve housing by a positive connection in the axial direction so firmly that the actuator ensures reliable axial support for the working piston of the thermostatic working element and its axial position on the valve housing is not changed under the influence of the axial forces acting from the working piston of the thermostatic working element. In all, the thermostat valve is simple and inexpensive. The invention creates the prerequisites for providing the holder for the actuator during the manufacture of the valve housing, e.g. as a molded part ready for installation, so that the actuator only has to be inserted and then firmly connected axially to the valve housing by flanging a flanged edge, whereby a seal can be provided if necessary to seal the inside of the valve housing from the outside.

Advantageous further inventive features and embodiments are contained in claims 2 - 14.

Further details and advantages of the invention will become apparent from the following description.

The full wording of the claims is not reproduced above solely to avoid unnecessary repetition, but instead reference is made to them only by naming the claim numbers, whereby all of these claim features are to be regarded as expressly disclosed at this point and essential to the invention. In this context, all of the features mentioned in the preceding and following

The features mentioned in the description as well as the features that can be inferred from the drawing alone are further components of the invention, even if they are not specifically highlighted.

and in particular are not mentioned in the claims. 5

The invention is explained in more detail below using an embodiment shown in the drawing. The drawing shows a schematic, axial longitudinal section of a thermostat valve.
10

The thermostat valve 10 shown in the drawing is, for example, similar to that according to DE-OS 33 15 308 or 37 05 232 and is used to regulate the temperature of the coolant of an internal combustion engine (not shown), in particular of a motor vehicle engine. The thermostat valve 10 regulates the flow of coolant from the internal combustion engine (not shown) through a bypass and/or through a heat exchanger (cooler) (not shown) back to the internal combustion engine.

The thermostat valve 10 has a valve housing 11, which has a connection piece 12, via which the coolant can be guided to the heat exchanger. In the valve housing 11, a thermostatic working element 13 is arranged, which has a working piston 14 and a housing 15, in which, in a known manner, an expansion material is located, which can expand when heated and can thereby push the working piston 14 out relative to the housing 15. When cooled, the expansion material reduces its volume. The working piston 14 is then moved back into the starting position relative to the housing 15 under the action of a valve spring 16, i.e. pressed into the housing 15.

A valve plate 17 is attached to the housing 15 of the working element 13, which is e.g. pressed on, flanged on or firmly attached in some other way. The valve plate 17

forms the valve closure element of the thermostat valve 10. Its outer edge is assigned a valve seat 18, e.g. approximately frustoconical, in the valve housing 11. The valve spring 16 is axially supported at one end by means of a bracket 19 or the like, which in turn is held in recesses 20 of hanging arms 21 of the valve housing 11. The other end of the valve spring 16 is supported on the valve plate 17 and strives to press the valve plate 17 in the valve closing direction according to arrow 22 and against the valve seat 18. This closed state is shown in the drawing. The valve formed from the valve plate 17 and the associated valve seat 18 closes or opens the connection between an inlet (not shown), which can be provided, for example, in the area of the arms 21 and in a housing there, and the connection piece 12 leading to the heat exchanger, in particular the cooler.

A further valve plate 23 is arranged on the housing 15 in a sliding manner and is supported on the housing 15 by means of a spring 24. The valve plate 23 serves in a known manner to control a bypass channel (not shown) contained in a connection housing and thus the direct return of the coolant back to the engine.

The working piston 14 of the thermostat valve 10 is axially supported on an abutment, which is generally designated 25. The drawing shows the thermostat valve 10 in the starting position when the internal combustion engine is cold. If the internal combustion engine is started, the working element 13 is supplied with the coolant coming from the engine, which is initially fed into the bypass channel (not shown) at a low temperature and with the valve plate 23 open, while the coolant cannot reach the interior 9 of the valve housing 11 and the connection piece 12 due to the closed valve plate 17. As the coolant heats up,

the expansion material in the housing 15 expands. When a temperature determined by the design of the expansion material is reached, the working piston 14 is extended over a certain working range according to a certain characteristic dependent on the expansion material. Since the working piston 14 is axially supported on the abutment 25, this results in a relative displacement of the housing 15 against the arrow 22 and the valve closing direction against the effect of the valve spring 16. The housing 15 is initially moved axially in such a way that over a certain temperature range both the valve plate 17 and the valve plate 23 of the bypass valve are now open. If the temperature then increases further, the bypass valve is closed via the valve plate 23 by further pushing the housing 15 out in the opposite direction to the arrow 22, while the other valve 17, 18 is now completely open.

In this mode of operation, the thermostat valve 10, in particular the thermostatic working element 13, is set to a temperature range in which the working piston 14 is extended from the housing 15 with a linear movement. This temperature range is determined by the choice of the expansion material and other parameters.

The abutment 25 is axially adjustable, whereby the working range of the thermostat valve 10 can be changed by external intervention.

The abutment 25 has an axially adjustable support part 26. The support part 26 consists of a sleeve 51 with holes 52, 53 on both sides, which run coaxially to one another and are open in opposite directions. The support part 26 can be adjusted by means of an actuator 36 in the valve closing direction according to arrow 22 and in the opposite direction, i.e. in the tension and compression directions. The actuator 36 can be used in a variety of ways as an externally controllable

-B-

Element. In the embodiment shown, the actuator 36 is particularly advantageously designed as a temperature-dependent working element 37 similar to the thermostatic working element 13. The actuator 36 is designed in particular as an expansion element that contains expansion material in a housing 38, into which a piston 39 is immersed, which is led out of the housing 38. The temperature-dependent working element 37 can be heated. An electrical heating element 40, for example, is used for heating, which here consists of a PTC element in a known manner.

This actuator 36 designed in this way, in particular the temperature-dependent working element 37, is arranged coaxially to the working piston 14. It is located on the axial side adjacent to the working piston 14. The support part 26 in the form of the sleeve 51 is firmly connected to the piston 39 and, if necessary, also to the working piston 14 in the tension and compression directions. By axially displacing the piston 39, an axial actuating force can be generated that is directed in the valve closing direction according to arrow 22 or in the opposite direction, which results in an axial adjustment of the working piston 14 via the support part 26. If the piston 39 of the actuator 36 is moved further upwards, e.g. in the valve closing direction according to arrow 22 and thus axially, the working piston 14, which is firmly connected to it, is also moved further upwards axially via the support part 26, which corresponds to a higher opening temperature for the working element 13. An axial movement in the opposite direction to the valve closing direction according to arrow 22 results in an axial displacement of the working piston 14 downwards in the drawing, which corresponds to a lower opening temperature for the working element 13. If the working range of the thermostatic working element 13 is to be adjusted to a lower response temperature, the circuit supplying the heating element 40 is closed. The

The electric heating element 40 heats up so that the expansion material contained in the housing 38 expands. This results in a relative displacement between the housing 38 and the piston 39 in the axial direction downwards, whereby the working range of the thermostat valve 10 is adjusted to a lower working temperature. If, instead, a different working position for the thermostat valve 10 is to be achieved, the circuit supplying the electric heating element 40 is opened. The heating and thus the warming of the working element 37 is thus interrupted so that the working element 37 can cool down again. The cooling results in a reduction in the volume of the expansion material in the housing 38. The piston 39 is therefore displaced relative to the housing 38 in the valve closing direction according to arrow 22 into a different position. In this position, the temperature-dependent working element 13 is set to a higher opening temperature, so that it only opens in the manner described above when the coolant temperature is higher.

The actuator 36, in particular the temperature-dependent working element 37, is held on the valve housing 11. It is located outside the interior 9 of the valve housing 11. The actuator 36, in particular the temperature-dependent working element 37, is attached to the valve housing 11 by a flange connection 54. The valve housing 11 contains a receiving opening 55 in which the actuator 36, in particular the temperature-dependent working element 37, is received and held with at least one longitudinal section 56. The actuator 36 is fitted into this receiving opening 55 with the longitudinal section 56, whereby the actuator 36 can be held therein by a plug connection. In any case, the receiving opening 55 and the longitudinal section 56 fitted therein ensure a secure centering of the actuator 36 in relation to its longitudinal center axis and the coaxial longitudinal center axis of the

thermostatic working element 13.

The valve housing 11 has a flanged edge 57 at the free end of the receiving opening 55, which is bent towards the actuator 36 after it has been inserted and positively engages over a radial projection 58, in particular an annular shoulder, of the actuator 36.

The valve housing 11 is designed as a molded part, e.g. made of die-cast aluminum, on which the receiving opening 55 is formed with a flanged edge 57. The receiving opening 55 is aligned so that the actuator 36 and its piston 39 are arranged coaxially to the working piston 14, with the actuator 36 being arranged on the axial side adjacent to the working piston 14 and thus outside the interior 9 of the valve housing 11. The piston 39 of the temperature-dependent working element 37 is guided through a through opening 59, e.g. a bore, contained in the valve housing 11 into the interior 9 of the valve housing 11 and to the sleeve 51. To seal the interior 9 in the area of this through opening 59 from the outside, a seal 60 is arranged between the working element 37 and the valve housing 11. The seal 60 consists, for example, of a sealing washer, a sealing ring, e.g. O-ring or the like.

The thermostat valve 10 is simple, inexpensive and can be assembled using simple means and in a modular manner, since, for example, the thermostatic working elements 13 and 37 can be of the same construction or at least functionally the same, with their working piston 14 or piston 39 engaging in the bore 52 or 53 of the sleeve 51 and being firmly connected to the latter, for example. The thermostat valve 10 also has the advantage that the actuator 36, in particular the temperature-dependent working element 37, can be firmly connected to the valve housing 11 quickly, easily and inexpensively.

Any machining work for attachment to the

Valve housings 11 are not necessary if the valve housing 11 is advantageously formed from a molded part, e.g. made of aluminum die-casting, in which the receiving opening 55 with a flanged edge 57 at the end, e.g. reduced in cross-section, is formed at the same time. It is then only necessary to insert the actuator 36, in particular the temperature-dependent working element 37, into the receiving opening 55 and to position the flanged edge 57 behind the radial projection 58, e.g. the one formed on the housing 3Θ.

I^ th ring shoulder, so that a loss-proof and mechanically strong axial fixation of the actuator 36 on the valve housing 11 is ensured, which is able to absorb the axial support forces for the working piston 14.

Claims (1)

Expectations 1. Thermostat valve for regulating the temperature of the coolant of an internal combustion engine, in particular a motor vehicle engine, which regulates the flow of coolant from the internal combustion engine through a bypass and/or through a heat exchanger back to the internal combustion engine, wherein a housing (15) containing an expansion material is provided, which is acted upon by a valve spring (16) in the valve closing direction, carries at least one valve plate (17) and contains a working piston (14) which extends relative to the housing (15) when heated and causes the stroke of the valve plate (17), to which an adjustable support part (26) is assigned as an abutment (25), which is connected to the working piston (14) and can be adjusted by means of an actuator (36) which is held on the valve housing (11), characterized in that the actuator (36) is attached to the valve housing (11) by a flange connection (54). 2. Thermostat valve according to claim 1, characterized in that the valve housing (11) has a receiving opening (55) which accommodates the actuator (36). -2- and that the actuator (36) is received and held with at least one length section (56) within the receiving opening (55). 3. Thermostat valve according to claim 1 or 2, characterized in that the actuator (36) with the longitudinal section (56) is fitted into the receiving opening (55). 4. Thermostat valve, in particular according to one of claims 1-3, characterized in that the actuator (36) with the longitudinal section (56) is held in the receiving opening (55) by a plug connection, bayonet connection or the like. 5. Thermostat valve according to one of claims 1-4, characterized in that the valve housing (11) has a flanged edge (57) at the free end of the receiving opening (55), which engages in a form-fitting manner over a radial projection (58), in particular an annular shoulder, of the actuating element (36). 6. Thermostat valve according to one of claims 1-5, characterized in that the valve housing (11) is designed as a molded part on which the receiving opening (55) with a flanged edge (57) is formed. 7. Thermostatic valve according to one of claims 1-6, characterized in that the actuator (36) is arranged coaxially to the working piston (14). &THgr;. Thermos valve according to one of claims 1-7, characterized in that the actuator (36) is mounted on the working piston (14) -3- * adjacent axial side and outside the interior (9) of the valve housing (11). 9. Thermostat valve according to one of claims 1-8, characterized in that the actuating element (36) is designed as a temperature-dependent working element (37). 10. Thermostat valve according to one of claims 1-9, characterized in that the actuator (36) is designed as a heatable, in particular electrically heatable, temperature-dependent working element (37). 11. Thermostat valve according to one of claims 1 - 10, characterized in that the actuator (36) is designed as an expansion element, which has an expansion material contained in a housing (38) into which a piston (39) is immersed, which is led out of the housing (38). 12. Thermostat valve according to claim 11, characterized in that the piston (39) is arranged coaxially to the working piston (14) and is guided through a through opening (59) in the valve housing (11) into the interior (9) of the valve housing (11). 13. Thermostat valve according to claim 11 or 12, characterized in that the support part (26) is firmly connected to the piston (39) and to the working piston (14) in the tension and compression directions. 14. Thermostatic valve according to one of claims 11 - 13, characterized in that between the actuator (36), in particular temperature-dependent -A- Working element (37), and the valve housing (11) a seal (60), e.g. a sealing disk, a sealing ring, an O-ring or the like, is arranged which seals the interior (9) of the valve housing (11) in the area of the through opening (59) to the outside.