WO2009124766A2

WO2009124766A2 - Thermostatic control device

Info

Publication number: WO2009124766A2
Application number: PCT/EP2009/002639
Authority: WO
Inventors: Jürgen SOHN
Original assignee: Otto Egelhof Gmbh & Co. Kg
Priority date: 2008-04-11
Filing date: 2009-04-09
Publication date: 2009-10-15
Also published as: DE102008018639A1; DE112009000311A5

Abstract

The invention relates to a thermostatic control device for controlling a mass flow which can be controlled especially by means of a valve element (18) for opening and closing a throughbore (19) in a valve housing (12), comprising a housing section (31) in which an actuating unit (37) is provided which produces, depending on the temperature, an actuating movement onto a transmission pin (38) by which movement the valve element (18) can be controlled, the actuating unit (37) being produced of a shape memory alloy.

Description

Thermostatic control device

The invention relates to a thermostatic control device for controlling a mass flow which can be controlled in particular by a valve element for opening and closing a through hole in a valve housing, with a housing portion in which an actuator is provided, which generates a temperature-dependent adjusting movement on a transmission pin.

For heating a room air, for example, radiators are provided, the respective heating temperature is adjustable by a thermostat. At a feed to the radiator, a valve housing is provided with a valve element which opens and closes a through hole. This valve element comprises a receiving device in which a spring element is arranged. These recording tion is inserted into the valve housing. In an initial position, the valve closure member is lifted relative to the valve seat in the valve housing, and the valve housing is thus opened. From the receiving device protrudes a pin end. At this pin end attacks a thermostatic control device, which is also referred to as a thermostatic head. By such a thermostatic control device, for example, a frost protection, a night temperature and, for example, five other different temperature levels can be set. This is done via a thermal actuator, which is provided in the thermostatic head. As the room temperature increases, the thermal actuator generates an actuating movement, which is transmitted to the valve element via a transmission pin, so that the valve element closes the through-bore in the valve housing. As soon as the temperature drops below the preset temperature value, the thermal actuator reduces its lifting movement, whereby the valve element opens.

For controlling a Hubbeweguπg by the thermostatic control device, for example, a liquid-filled actuator is known, in which a corrugated tube is provided. Within this corrugated tube a Überhubsicherung is provided to prevent damage to the corrugated pipe with increasing heating and thus increasing pressure. As an alternative to a liquid-filled actuator and gas-filled actuators are known. In addition, instead of an actuator which can be controlled via a liquid or a gas in its lifting movement, an actuator with a wax expansion element is known. All of these aforementioned actuators are basically the same structure and have a Überhubsicherung to avoid that occurs at an elevated pressure damage in the thermostatic control device. Although such thermostatic control devices have a large volume, but these have proven themselves in practice. Increasing demands on the design and flexibility in use, these thermostatic control devices only partially meet. The invention is therefore based on the object to propose a thermostatic control device, which allows an alternative control and in particular the formation of such a thermostatic control device with a small volume.

This object is achieved by the features of claim 1. Further advantageous embodiments and further developments are specified in the further claims.

By the thermostatic control device for controlling a mass flow with a thermal actuator, which is formed from a shape memory alloy, a structurally very simple structure and a simple configuration of such a thermal actuator can be created. Furthermore, due to the use of a shape memory alloy material for the actuator, a very compact design has been made possible. Such shape memory alloys, which are also referred to as SMA (Shape Memory Alloy) alloys, allow an adjustment movement and an exact control of a stroke as a function of the temperature. Moreover, the shape memory alloy thermal actuator has the advantage that in the case of over-force, that is, force generation that exceeds the force for keeping a valve member closed, deterioration or damage of the actuator does not occur.

According to a preferred embodiment of the invention it is provided that the thermal actuator is designed as a spiral spring element. Thereby, the required stroke can be determined by determining the number of turns and / or the wire diameter in a simple manner. Alternatively it can be provided that the thermal actuator is designed as a plate spring, wherein a plurality of elements are stackable in opposite directions. In addition, a further clamping element may be provided, the stroke is controlled via an actuator made of a shape memory alloy. The thermal actuator, which consists of a shape memory alloy, is preferably independent of the temperature of the valve element flowing through the mass flow controllable. By decoupling between the temperature of the controllable mass flow and an ambient temperature of the thermostatic control device, this thermostatic control device, for example, as a room temperature control, preferably in a thermostatic head, are used.

The shape memory alloy thermal actuator preferably has a linear change in length at least in a temperature range of 15 ° to 25 °, preferably in a temperature range of 5 ° to 30 °. This creates a linear adjustment range that is suitable for room temperature control. Thus, for example, due to a rotational movement of an adjustment of the thermostatic control device, preferably on the thermostatic head, an immediate pre-adjustment of the valve element carried out to achieve a corresponding heating of the ambient or room temperature.

According to a further advantageous embodiment of the invention it is provided that the thermal actuator is supported on a setting surface of the thermal head, which is movable relative to the housing portion. Opposite the adjusting surface is arranged on the transmission pin, a support element on which the actuator is also supported. At least in the assembled state of the thermostatic control device on the valve housing, the thermal actuator is arranged under a defined bias to the valve element. The bias of the thermal actuator corresponds to at least one restoring force of a return element, which arranges the valve element in an open position to the through hole in the valve housing.

Furthermore, it is preferably provided that the housing portion has a captive securing, by means of which the transmission pin and the actuator can be positioned to the setting surface of the thermal head. Once the thermostatic control device is attached to the valve body and the transfer pin of the thermostatic control device bears against the transfer pin of the valve element, the thermostatic actuator assumes a defined position. Until this time, it is desirable that the thermal actuator and the transfer pin to the thermostatic control device, in particular to the thermostatic head, are held captive.

The captive is preferably designed as a detachable or lockable insert that is attachable in or on the housing portion. In particular, the captive or the use of a through hole, which also serves as a guide for the transmission pin, through which the thermal actuator is received.

Alternatively, the captive can also be designed so that on an inner circumference of the housing portion or the support member which engages the transmission pin, guide elements are provided, which cause the thermal actuator to the housing portion and / or prefix.

According to a further preferred embodiment of the invention it is provided that the support element for adjusting the bias of the actuator along the longitudinal axis of the transmission pin is changeable in its position. For example, the setting can be done via a thread. Likewise, individual detents may be provided which allow a change in the setting of the bias.

According to a further preferred embodiment of the invention, a plane stop surface is provided on one of the engagement surface opposite end of the transfer pin. As a result, a defined contact surface to the transmission pin of the valve element, which is provided in the valve housing. Such a separation point or interface can also be formed in that the contact surface of the transmission pin which receives the thermal actuator has an elevation or depression to allow a positionally secure arrangement on the transmission pin of the valve element. For exact control of the thermal actuator, a thermal insulation of the thermal actuator is preferably provided. In this case, preferably, the transmission pin and the support element and the attack surface of a thermally insulating material, in particular plastic, formed or coated with a thermally insulating material or coated.

A further alternative embodiment of the thermostatic control device provides that the valve closing member of the valve element is arranged on the thermal actuator receiving pin and instead of the two-part embodiment described above, a one-piece or one-piece design of the transfer pin is provided. This is made possible in particular by the fact that the separation point between the transmission pin, which receives the thermal actuator, and the transmission pin, which receives the valve element, is eliminated. As a result, a thermostatic control device with an integrated valve element can be created.

According to a further preferred embodiment of this alternative embodiment, it is provided that acts on the transmission pin, a restoring element, which counteracts the actuator with a force. It can thereby be achieved that the valve element is in an open position and a flow of the mass flow is possible. It is preferably provided that the transmission pin traverses a receiving device, which receives the at least one return element. This restoring element is arranged in the receiving device in such a way that the valve element is in an open position without a forced reset. Alternatively, the restoring device can also be arranged outside the receiving device and act on the transmission element carrying the valve element. Alternatively, a restoring element can also be provided inside and outside the receiving device.

According to a further preferred embodiment of the alternative embodiment, it is provided that the receiving device is at least insertable into the valve housing. Subsequently, for example fixed by means of a screw connection of the housing section of the thermostatic control device to the valve housing. In this case, an adjustment of the valve closing member to the valve element is preferably provided, in which in an initial position of the restoring element, an open position of the valve closing member is arranged to the through hole.

The restoring element arranged in the receiving device is preferably designed as a spring element whose preload can be adjusted by a stop. This adjustment can be made in dependence on the set bias of the thermal actuator to allow Einjustierung the thermostatic control device.

The invention and further advantageous embodiments and developments thereof are described in more detail below with reference to the examples shown in the drawings and explained. The features to be taken from the description and the drawings can be applied individually according to the invention individually or in combination in any combination. Show it:

Figure 1 is a schematic sectional view of a thermostatic control device for controlling a valve and

Figure 2 is a schematic sectional view of an alternative embodiment of the thermostatic control device, which comprises a valve element.

FIG. 1 shows a schematic sectional illustration of a thermostatic control device 11. The thermostatic control device 11 is particularly intended to control a room temperature. Such thermostatic control devices 11 are also referred to as a temperature sensor or simply as a thermostat. The thermostatic control device 11 is mounted on a valve housing 12, which is formed for example as an angle valve. This valve housing 12 has an inlet opening 14 and a drain opening 16 on, wherein the drain opening 16 opens directly into a heating surface element, such as a radiator or the like. In the valve housing 12, a valve element 18 is provided which can be actuated to open and close a through hole 19. The valve element 18 is arranged on a transmission pin 21, which passes through a receiving device 22. This receiving device 22 is secured, for example via a screw thread in the valve housing 12 media-tight. In the receiving device 22, a return element 24 is provided. This is for example designed as a return spring. The restoring element 24 rests on the one hand on the receiving device 22 and on the other hand on a stop 26, on which is attached to the transmission pin 21. The pressing force of the restoring element 24 is adjusted such that in a basic position the stop 26 bears against an adjusting sleeve 27 of the receiving device 22. Such a basic position is provided when the thermostatic control device 11 is not mounted on the valve housing 12. This open position of a valve closing member 28 to the valve seat 29 of the valve member 18 is provided as a Sichεrheitsfunktion.

The thermostatic control device 11 comprises a housing section 31, which has at one end a fastening element 32, in particular a cap nut, in order to position the housing section 31 to the valve housing 12. Furthermore, an adjusting device 34 is provided on the housing section 31. This adjustment device 34 is also referred to as a thermal head. The adjusting device 34 is rotatably disposed on the housing portion 31, wherein on the outer circumference of the adjusting device 34, a scale is provided to make the set position of the thermostatic control device 11 to the user visible.

In the adjusting device 34, a setting surface 36 is provided, on which a thermal actuator 37, which consists of a shape memory alloy attacks. This thermal actuator 37 is preferably designed as a spiral spring and is received by a transmission pin 38. At the transmission pin 38, a support member 39 is provided, on which the thermal actuator 37 is supported. The Support member 39 may be both a part of the transfer pin 38 and be provided in its position changeable to the transfer pin 38. This can be done for example via a screw connection. Thereby, the biasing force of the thermal actuator 37 can be adjusted.

The transfer pin 38 has, at one end of the adjustment surface 36, a stop surface 41 which bears against an equally formed surface on the transfer pin 21 of the valve element 18 as soon as the thermostatic control device 11 is mounted on the valve housing 12.

In the adjustment surface 36 of the adjusting device 34, a recess 43 is provided, in which the transmission pin 38 is immersed. As a result, a radial guidance and fixing of the transmission pin 38 can be provided.

Furthermore, a captive 45 is preferably provided in the housing portion 31. This captive 45 may be formed, for example, as a collar with a through hole 46. This through-hole 46 is preferably used to guide the transmission pin 38. The captive 45 may for example be integrally provided on the housing portion 31. Furthermore, the captive 45 may be formed as an insert, which is fixed, for example, releasably or by a cohesive connection in the housing portion 31. Alternatively, a locking connection or the like may be provided.

Instead of the above-described embodiment may also be provided between the captive 45 and the support member 39 which engages the transmission pin 38, in addition, a return element to support the opening movement of the return element 24 in the receiving device 22. As a result, it may be possible to fine-tune the actuator 37. Furthermore, it is alternatively possible for the restoring element 24 not to be arranged in the receiving device 22, but to be used as an example between the captive embankment tion 45 and the support member 39. In this case, the transmission pin 21 and the transmission pin 38 are firmly connected to each other by a coupling element, so that in turn an independent opening of the thermostatic control device 11 is made possible.

The arrangement of the thermostatic control device 11 and of the valve element 18 shown in FIG. 1 has, for example, a setting in which the adjusting device 34 is in the position 1 with its scaling. This position 1 may be, for example, a night temperature, which places the valve closure member 28 in an almost closed position to the valve seat 29, so that a room temperature of, for example, 14 ° or 15 ° is adjustable. So that this position can be taken, the spring force of the thermal actuator 37 is greater than the restoring force of the return element 24 interpret, so that the stop 26 is lifted at least to a small extent relative to the adjusting sleeve 27. As soon as the room temperature should drop to a temperature below the set temperature of, for example 14 ° or 15 °, the spring force of the thermal actuator 37 decreases from the shape memory alloy, and the valve closure member 28 is further lifted from the valve seat 29, so that a larger mass flow Valve housing 12 can flow through. Once the room temperature has reached or slightly exceeds the preset temperature, in turn, the spring force of the thermal actuator 37 increases and the valve closure member 28 returns to the preset position.

With a setting of the adjusting device 34 to a position 5, a distance between the stop 26 and the adjusting sleeve 36 of the receiving device 22 may still be present or the stop 26 is applied to the adjusting sleeve 27 at.

To set an antifreeze, the adjusting device 34 is transferred to a position in which the thermal actuator 37, the valve closing member 28 is transferred to a closed position, so that it rests in the valve seat 29. At the same time the restoring element 24 is acted upon by a force, that is, a distance between the Stop 26 and the adjusting sleeve 27 sets. As soon as a temperature is equal to or less than 5 °, the force of the thermal actuator 37 decreases. Due to the then increased restoring force of the return element 24, the valve closing member 28 is lifted from the valve seat 29, so that at least a small mass flow can flow through the heating medium.

The shape memory alloy for forming the thermal actuator 37 is preferably selected such that at least in a temperature range of 15 ° to 25 °, a linear adjustment range is made possible. Preferably, a temperature range is selected which comprises 4 ° or 5 ° to 30 °. Such shape memory alloys used for example consist of a TiNi alloy, an alloy of copper base, Fe base or of a memory plastic.

FIG. 2 shows an alternative embodiment of the invention. In this embodiment, the thermostatic control device Ii comprises the valve element 18 and is formed as a structural unit due to the one-piece or integrally formed transmission pin. The transfer pins 21 and 38 are fused to a transfer pin or coupled together by a detachable connection. As a result, the valve element 18 and the thermostatic control device form a structural unit. For mounting it is provided that first the valve closing member 28 is inserted into the valve housing 12. At the same time, the receiving device 22 is positioned in the valve housing 12. Subsequently, the housing section 31 is fixed to the valve housing 12 by the fastening element 32. Then the assembly is complete. The features and embodiments mentioned in FIG. 1 also apply to the thermostatic control device 11 with integrated valve element 18 shown in FIG.

In this embodiment may alternatively be provided that the return element 24 may be positioned instead of the positioning within the receiving device 22 outside of the receiving device 22 and engages the support member 39 on the transfer pin 38 and opposite either on the adjusting sleeve 27 or on a End face of the housing 12 is supported. Furthermore, a restoring element 24 can be provided both inside and outside the receiving device 22.

Alternatively it can be provided that the embodiment shown in Figure 2 is formed in two parts, for example, the housing portion 31, the fastener 32 and the adjusting device 34 mounted thereon a part and the remaining components form the second part. Thereby, a separate attachment and screwing of the receiving device 22 may be provided on the valve housing 12. To secure the thermal actuator 37 may still be arranged at the free end of the transfer pin 38, a locking washer or the like. Also for this alternative embodiment, the previously described advantageous embodiments apply.

Claims

claims

1. Thermostatic control device for controlling a mass flow, which in particular by a valve element (18) for opening and closing a through hole (19) in a valve housing (12) is controllable, with a housing portion (31) in which an actuator (37) provided is which temperature-dependent an adjusting movement on a transmission pin (38) generated by which the valve element (18) is controllable, characterized in that the actuator (37) is formed of a shape memory alloy.

2. Control device according to claim 1, characterized in that the actuator (37) is designed as a spiral spring element.

3. Control device according to claim 1, characterized in that the temperature-dependent adjusting movement of the actuator (37) is controllable independently of the temperature of the mass flow to be controlled.

4. Control device according to one of the preceding claims, characterized in that the actuator (38) consists of a shape memory alloy, which has a linear change in length at least in a temperature range of 15 ° to 25 °, preferably in a temperature range of 5 ° to 30 ° ,

5. Control device according to one of the preceding claims, characterized in that the actuator (37) on a setting surface (36) of an adjusting device (34) is supported, which is movable relative to the housing portion (12) and that the actuator (37) opposite to a supporting element (39) engages, which is connected to the transmission pin (38).

6. Control device according to one of the preceding claims, characterized in that the housing section a Verliersi- has (45) through which the transmission pin (38) and the actuator (37) to the adjustment surface (36) are positionable.

7. Control device according to claim 6, characterized in that the captive (45) is designed as a detachable or lockable insert with a through hole (46) for the transmission pin (38), which is formed in particular by guiding the transmission pin (38).

8. Control device according to one of the preceding claims, characterized in that at least partially guide elements are provided on an inner circumference of the housing portion (12) or on the support element (39).

9. Control device according to claim 5, characterized in that the support element (39) for adjusting a bias of the actuator (37) along the longitudinal axis of the transmission pin (38) is variable in its position.

10. Control device according to claim 5, characterized in that on one of the adjusting surface (36) opposite end of the transmission pin (38) has a stop surface (41) on the transmission pin (38) is provided.

11. Control device according to one of the preceding claims, characterized in that the actuator (37) thermally insulated in the housing portion (31) is arranged.

12. Thermostatic control device according to one of the preceding claims, characterized in that a transmission pin (21) of a valve element (18) which receives a valve closing member (28) and the transmission pin (38) integrally formed or firmly connected to each other.

13. Control device according to claim 12, characterized in that acts on the transmission pin (21) a return element (24), which counteracts with a force the actuator (37) or the valve closure member (28) of the valve element (18) transferred to an open position and that preferably the transmission pin (21) passes through a receiving device (22) in which a return element (24) is arranged ,

14. Thermostatic control device according to claim 13, characterized in that the receiving device (22) at least in a valve housing (12) can be inserted and positioned so that in an undeflected position of the return element (24) the valve closure member (28) in an open position for Through hole (19) in the valve housing (12) is arranged.

15. Control device according to claim 13 or 14, characterized in that the restoring element (24) is designed as a spring element whose bias is adjustable by a stop (26).