WO2007031079A1

WO2007031079A1 - Valve attachment for a valve, especially a heater valve or radiator valve

Info

Publication number: WO2007031079A1
Application number: PCT/DK2006/000434
Authority: WO
Inventors: Bjarne Frederiksen
Original assignee: Danfoss A/S
Priority date: 2005-08-10
Filing date: 2006-08-09
Publication date: 2007-03-22
Also published as: CN101283321B; DE102005038067B4; CN101283321A; DE102005038067A1

Abstract

Disclosed is a valve attachment (1) for a valve, especially a heater valve or radiator valve. Said valve attachment (1) comprises a housing (2), an actuating element (8) that is movable in an actuating direction inside the housing (2), and an electric motor (5) which acts upon the actuating element (8) via a spindle drive (8, 27). In order to create a compact electrically controllable valve attachment, the motor (5) is connected directly to a rotating element (8) of the spindle drive (8, 11 ; 8, 27).

Description

_-] _

Valve attachment for a valve, in particular Heizunqs- or cold valve

The invention relates to a valve cap for a heating or cooling valve having a housing, a displaceable in the housing in an actuating direction actuating element and an electric motor which acts via a spindle drive on the actuating element.

The invention will be described below in connection with a radiator valve. However, it is also applicable in a manner applicable to a valve which controls the flow of a refrigerant through a cooling surface or a heat exchanger used for cooling.

Radiator valves are usually controlled by a thermostatically operating thermostatic valve top. The thermostatic valve attachment contains a thermostatic element whose expansion varies with temperature. When the temperature measured by the thermostatic element is high, the expansion of the thermostatic element increases. This then acts throttling on the radiator valve. When the temperature is low, the expansion of the thermostatic element decreases accordingly and a larger flow of heat transfer medium through the radiator valve is released.

Such valve heads have proven themselves. However, they usually allow only a local influence of the radiator.

Another type of valve attachment uses a motor to control the valve. Such a valve tower is known for example from DE 34 01 154 A1. The valve cap contains an electrical rotati- onsmotor, which adjusts a gear with a plurality of large and small gears a disc having an inclined actuating surface. The actuating surface in turn acts on a valve stem. Ultimately, the actuating surface may turn a maximum of once to exploit the full stroke of the valve lifter can. This makes the control difficult. The transmission reduces the efficiency, so that such a valve cap requires relatively much power and also builds relatively large.

A valve attachment of the type mentioned is known from US 5 137 051. Here, the engine acts via a gear on a spindle, which rotates in a non-rotatably held nut. Upon rotation, the nut shifts and acts on a valve lifter via an overload protection, which includes a compression spring. Again, the valve attachment builds relatively large. The transmission reduces the efficiency of the valve top, so that one has a relatively high power consumption during an adjustment. In addition, a transmission usually causes noise, which are particularly undesirable if such a valve cover to be used in the living area or in the sleep area.

The invention has for its object to provide an electrically controllable valve cap, which is compact.

This object is achieved in a valve attachment of the type mentioned above in that the motor is directly connected to a rotating element of the spindle drive.

This saves a gearbox between the engine and the spindle drive. The motor thus acts translation-free on the spindle drive. This can be achieved with a relatively simple structure that the valve cap work with an adjustment of the valve with a very good efficiency can. The noise remains small because there are fewer moving parts. Basically, it is just the motor and the spindle drive, in which one element rotates and another element is translationally displaced due to the rotation. Other parts that need to be moved, 5 omitted.

Preferably, the motor is designed as a stepper motor. A stepper motor can be controlled step by step. If you know the number of steps performed, then you also know which displacement the spindle drive 0 has performed. In this case, one also knows which position the actuator has. You can chain this position directly with a given opening and thus a predetermined temperature.

Preferably, the motor is designed as a piezomotor. The motor 5 thus has at least one piezoelectric element, which expands at a voltage application and contracts at a negative or reduced voltage. Now you can take advantage of these expansion and contraction movements of the piezoelectric element to operate the engine. In other words, a surface is vibrated o, so that a kind of carrier wave is formed. With the help of this carrier wave, it is possible to determine the position of the motor by counting the vibrations and thus the steps. A piezo motor is inherently self-locking. This results in the possibility of self-locking or self-locking exclusively via the piezoelectric motor, so that all other transmission elements can be optimized to other specifications.

In this case, it is particularly preferred that the motor has a first motor element and a second motor element, between which a piezoelectric element arrangement is arranged in the direction of actuation. One can now, for example, by a corresponding pressurization of the piezo element arrangement cause the desired length expansion. The piezoelement arrangement can have one or more piezoelements.

It is particularly preferred that the first motor element and the second motor element each have a diameter extension, wherein the piezoelectric element arrangement is arranged in the region of the diameter enlargement. With the diameter enlargement, the piezoelectric element arrangement has a larger area at which it can support itself.

In a very particularly preferred embodiment, it is provided that the first motor element as a rotor and the second motor element are designed as a stator, wherein the two motor elements via a threaded separation tion with each other. The connection can also take place indirectly, for example via intermediate pieces, which are connected in a rotationally fixed manner to the stator and / or the rotor. In this case, the piezoelectric element arrangement is not only exploited to effect a displacement of the actuating element by expansion or contraction. The piezo element arrangement is used in an example sinusoidal excitation to rotate the rotor and the stator against each other. This rotational movement can be translated by the corresponding thread pairing in a displacement of the actuating element. Depending on the driving direction of the piezoelectric element arrangement, the rotor can be rotated relative to the stator in one direction, for example in the clockwise direction, or in the opposite direction, ie counterclockwise, so that a corresponding displacement both in the direction of the valve and in the direction of the valve away is possible. Vorzugswθise, the spindle drive on a non-rotating element which is supported on an end wall of the housing. The motor thus forms a kind of spreading device, which acts on a valve tappet, in that the motor spreads or contracts between the end face of the housing and the valve tappet. In other words, the unit of motor and spindle changes their axial length. Thus, in each case sufficient counterforce is present to push an actuating pin of the valve sufficiently into the valve to close or open the valve.

It is preferred that the end wall is displaceable. This can be used to set a reference point for the valve top.

Preferably, the end wall forms part of a rotary handle. With the rotary handle can then, if desired, override the effect of the engine.

Preferably, the spindle drive is arranged in a region which is surrounded by the rotor at least over part of its axial length. This achieves that the essay can build comparatively short.

The valve attachment normally has an outer diameter which is adapted to the human hand. Accordingly, there is sufficient space in the interior of the valve cap to accommodate a motor with a larger diameter. This can generate sufficient torque. The power generation on a smaller radius of the motor, however, is negligible, so that you can accommodate the spindle drive here.

Preferably, the motor is controllable without wires. So you need no lines to control the engine. Rather, you can here

Use radio waves, for example, according to the so-called "bluetooth" Technology. Other types of transmission, such as infrared rays or ultrasound, are possible.

Preferably, the stator of the motor is held stationary in the housing. This avoids a movement that could adversely affect electrical connection lines that are needed to power the motor. The risk that such cables are torn or damaged, thus significantly reduced.

It is also advantageous if the rotor and the stator of the motor are clamped together with a predetermined axial force. Such a design is of particular advantage in piezo motors. If the rotor and stator clamp the piezo element arrangement between them, then the motor can act optimally. 5

It is preferred that a spring arrangement acts on the motor in the axial direction. With a spring arrangement can be achieved in a simple manner, the predetermined clamping force.

o It is preferred that the spring arrangement has a spring washer acting on the rotor. With a spring washer can be produced on a relatively short way the necessary force. A spring washer therefore requires relatively little space. In addition, it can be mounted relatively easily. It is also possible to arrange a friction-reducing layer between the spring washer and the rotor, for example made of ceramic or plastic, in particular PTFE.

Preferably, the spring washer is supported on a locking ring held in the housing. This is an easy way to hold the spring washer in place. Alternatively, the spring washer may be supported on a projection of the end wall. In this case, a shape on the housing is required, which is used to support the spring washer.

It is also advantageous if the motor has a decoupling device, the axial forces acting on the actuating element from the valve, keeps away from the rotor. As stated above, it is advantageous when acting on piezo motors with a certain force on the motor so that the piezo element assembly is clamped between the rotor and stator. At the same time it is important that the force does not increase beyond the predetermined level. Accordingly, it is also advantageous if the spring force acting back from the valve does not act on the engine. This could result in it not being able to rotate as freely as desired. This results in greater friction and increased wear. If you now make sure that the axial forces are kept away from the rotor, then you get in this respect ideal operating conditions, without otherwise compromising the functionality would have to do.

It is preferred that the rotor rotatably with an axially displaceable relative to the rotor driver is in communication, which is in engagement with the actuating surface. The driver is then the part of the engine that causes the change in length. Since it is only in the direction of rotation with the rotor engaged, in the axial direction, however, is displaceable, axial forces can be kept away from the rotor.

The invention will be described below with reference to preferred embodiments in conjunction with the drawings. Herein show:

1 shows a first embodiment of a valve cap in cut-open perspective view, 2 is a modified embodiment of the valve tower with twist grip,

3 shows a third embodiment of a valve attachment in the schematic longitudinal section and

4 shows a modification of the embodiment according to FIG. 3.

Fig. 1 shows a valve cap 1 in a schematic representation. The valve tower 1 has a housing 2, which is provided with a fastening device 3. The housing is formed substantially hollow cylindrical. It has an end wall 4.

In the housing 2, a motor 5 is arranged, which has a stator 6 and a rotor 7. In operation, the rotor 7 rotates, thereby moving a driver 8, which has an internal thread 9. The internal thread 9 is screwed onto an external thread 10, which is arranged on an extension 11 of the stator, which in turn is supported on the end wall 4 of the housing 2.

The driver 8 is connected to an actuating element 13, which has an actuating surface 14, against which, in the mounted state, a tappet 15 (FIG. 3) bears against a valve which is otherwise not shown in detail. Usually, the plunger 15 is in the opening direction under the bias of a spring. When the driver 8 and thus the actuator 13 move, then the plunger 15 is pressed more or less far into the valve to close it or open.

Fig. 2 shows a modified embodiment, in which the same elements are provided with the same reference numerals. The holder 12, protruding from the extension 11, is part of a rotary handle 16 which is screwed onto an external thread 17 of the housing 2. If the rotary handle 16 is rotated, then the position of the motor 5 is changed because the stator 6 of the motor 5 abuts against the carrier 12. Thus, the effect of the motor 5 can be overridden. Alternatively, another zero or starting point can be set.

Fig. 3 shows in section schematically a further embodiment in which the end wall 4 in the housing 2 can also be displaced. For this purpose, the end wall 4 is screwed into an internal thread of the housing 2. The end wall 4 expediently has torque application surfaces not shown in detail, so that the end wall 4 can be rotated relative to the housing 2.

From Fig. 3, the structure of the motor 5 can be seen better. The stator 6 of the motor is stationary in the housing 2. For this purpose it is axially secured on a step 19 of the housing and closely enclosed by the housing 2 in the circumferential direction, so that it is fixed in the radial direction.

The rotor 7 has a small distance 20 to the stator 6, in which a piezoelectric element 21 is arranged. It is also possible to use a plurality of piezoelectric elements 21. For the sake of simplicity, however, the following explanation is made with a piezoelectric element 21. The piezoelectric element 21 is formed by a piezoceramic, the extent of which changes with a voltage application. The expansion change of the piezoelectric element 21 in this case has a component in the circumferential direction of the stator 6, so that one can rotate the rotor 7 with respect to the stator 6 by a corresponding voltage application of the piezoelectric element 21. The piezoelectric element 21 is pulsed or cyclically acted upon by sinusoidal voltage pulses. For each voltage pulse then results in a predetermined Winkelinkrement by which the rotor 7 is rotated relative to the stator 6. The motor 5 is therefore designed as a stepper motor. One then "knows" on the basis of the number of pulses (or other supply data), in which angular position the rotor 7 relative to the stator 6 and, since the angular position of the rotor 7 relative to the stator 6 is always a statement about the change in length of the Extension 11 and the driver 8 formed spindle drive allows a statement about how far the actuating surface 14 is removed from the end wall 4 of the housing 2 (see Fig. 1). Accordingly, it is also possible to say exactly what degree of opening the valve 1 controlled by the valve has.

Fig. 3 differs from the embodiment according to FIGS. 1 and 2 in that the rotor 7 has a toothing 22, via which the rotor 7 is in communication with the driver 8, which simultaneously acts as an actuating element. The driver 8 is thus freely displaceable relative to the rotor 7 in the axial direction. Only in the direction of rotation it is firmly connected to the rotor 7. As a result, forces that act on the driver 8 via the plunger 15 do not transfer to the rotor 7.

The motor 5 can be supplied via a not-shown and arranged in the valve cap 1 battery with electrical power. Since the engine 5 only occasionally has to be put into operation to a

To change the opening degree of the valve, the consumption of the motor 5 is relatively low in electrical power.

Alternatively, one can also provide a supply device which contains a thermoelectric element in connection with solar cells. The thermoelectric element converts heat that passes through the valve anyway supplied hot heat transfer fluid is present in electrical energy. If such heat is not supplied, the sun usually shines, so that you get the necessary electrical energy with the help of solar cells. In this case, one is independent of a supply of electrical energy from the outside and basically does not need a battery either. However, a battery may be present for safety reasons. This can then be made smaller.

A Änsteuerung can be done from the outside, for example via a 0 not shown central unit. The control can be done via lines. But it can also be done without wires, for example via radio, infrared, "Bluetooth technology", etc.

The stator 7 and the rotor 6 of the motor 5 are 23 axially compressed by a spring washer. This spring washer 23 is held by an extension 24 of the end wall 4. Between the spring washer 23 and the rotor 6, a friction-reducing layer may be arranged in a manner not shown, for example made of ceramic or of plastic, in particular PTFE. The bias voltage with which the spring o disc 23 compresses the stator 6 and the rotor 7 is thus adjustable. Thus, the mechanical stress is adjustable, which acts on the piezoelectric element 21. The spring force can be optimized for optimum performance of the engine 5 out. This can save energy.

5 The driver 8 has an external thread 25 which is arranged in a housing element 27. The housing member 27 is supported on the end wall 4 and is rotatably connected to the end wall 4. If the housing element 27 can be made separate from the end wall 4, it may be made of a different material. For example, it is possible to optimize the end wall 4 for mechanical stability. For the housing member 27, however, you can choose a material that interacts with the driver 8 friction.

If now the motor 5 is put into operation, then the rotor 7 5 rotates the driver 8. The driver 8 moves depending on the direction of rotation in the housing element up or down. In this case, the position of the actuating surface 14 and thus the contact surface for the plunger 15 changes.

0 The forces acting on the motor 5 forces are determined exclusively by the spring washer 23. Forces arising from the valve, only affect the driver 8. This has the advantage that the engine 5 is always operated under well-defined conditions. Each electrical pulse that reaches the motor 5 then causes the adjustment of the rotor 6 by 5 a predetermined Winkelinkrement. The starting of the motor 5 is not complicated by excessive forces. A "slipping" of the rotor 6 relative to the piezoelectric element due to low forces is avoided. The axial separation of the rotor 6 and driver 8 also has the advantage that you can use different materials for rotor 6 and driver 8 o. The rotor 6 can be designed so that it has a large friction to the piezoelectric element 21. The greater this friction, the lower the preload can be selected. The driver 8, however, can be designed so that it interacts with the housing member 27 friction. 5

Such a valve cap has the advantage that the measurement of the room temperature can be done at a position that has a sufficient distance from the radiator. This eliminates P-band errors (the target temperature does not correspond to the temperature measured at the radiator) and so-called FTA errors (FTA = supply temperature dependence).

Otherwise, this error will almost always occur when the temperature is direct is measured at the valve top, because the heat of the heat transfer medium flowing through the valve will affect the temperature of a thermostatic element.

5 When attachment 1 is mounted on the valve, it can automatically detect a "zero point". This can be done, for example, that the motor 5 rotates until the valve is closed. This is signaled by a momentary increase. You then always have a safe reference point for the degree of opening of the valve. Of course you can 0 check this reference point at regular intervals.

Since the motor 5 is designed as a piezomotor and has a built-in "counter" as a stepping motor, one always knows the position of the plunger 15 and thus also the degree of opening of the valve. This can e.g. Be used to 5 to move the default in the valve cap 1, so that a Hubhöhenbegrenzung for the controlled by the essay 1 valve exists. A Hubhöhenbegrenzung is well known, but is normally used in conjunction with the valve element, so realized in a mechanical manner. The introduction of the default setting in the manner indicated here also allows a relatively simple change of this default, for example as a function of the seasons.

The adjustment of the degree of opening by means of the motor 5, in which the position of the actuating surface 14 is known exactly and therefore also 5 is referred to as "intelligent engine", also allows the generation of predetermined valve curves (S-curve, logarithmic curve, etc. ).

The stator 6 may preferably be cast with the housing 2, so it can be cast together with the housing 2 or poured into the housing o. Since the motor 5 is relatively small anyway, it is also possible to have control electronics (not shown) together with others Parts to install or pour. It may also be possible to install or pour in the batteries.

The control electronics can also be arranged outside of the attachment 1 5. In this case, it is connected via lines or without line to the motor 5.

The fact that one uses a motor 5, which is designed as a stepping motor and actually comes out practically no additional space, in turn means that one can have a modulating operation without problems. It is therefore easy to set an opening degree of the valve of, for example, 0.65 mm. For underfloor heating, this means that the flow can be adapted exactly to the needs. This is practically impossible with the on-off control systems that are used almost exclusively today, which are used with underfloor heating systems.

By exploiting the modulation and with the aid of intelligent control of the motor 5, it is again possible to obtain some advantages which were not possible in the past. If you e.g. has a system with a room temperature sensor and a radiator, which is controlled in each case by a valve cap 1, then the following is conceivable:

If the room thermostat is set to 25 ° in one day and measures only 5 23 °, the attachment must adjust the plunger 15 so that the desired

Room temperature is reached. If one then has a night setback, the room thermostat will know the next day that it has not reached the desired temperature on the first try and knows that it must introduce a correction so that the desired temperature is reached without an intermediate adjustment. Over time, it is then achieved that the motor 5 must work less and thus produce a smaller electrical current. has power consumption. This allows the supply of batteries without problems. The same applies to underfloor heating, which has a floor temperature sensor.

FIG. 4 shows an embodiment corresponding in essential elements to that of FIG. 3. Identical and functionally identical elements are provided with the same reference numerals.

The end wall 4 is no longer connected via a thread 18 to the housing 2. Rather, the end wall 4 has a circumferential projection 30 which engages in a corresponding groove 31 in the housing 2. Thus, the end wall 4 in the housing 2 is rotatable, without thereby changing the axial position of the housing member 27.

The housing member 27 is still rotatably connected to the end wall 4. The motor 5 is self-locking. Accordingly, with a rotation of the end wall 4 of the captured in the direction of rotation by the motor 5 driver 8 moves axially. It is thus possible by a rotation of the end wall 4, the driver 8 like to reload so that he closes the valve via the plunger 15. This can be manually find the zero point of the valve and then notify the control device not shown.

In addition, a screw 32 is now screwed through the end wall 4. The screw 32 forms a mechanical limit for the axial movement of the driver 8 upwards, in a heating valve so in the opening direction. With the help of the screw 32 so you can adjust how far the valve can be opened.

Claims

claims

1. Valve attachment for a valve, in particular heating or cooling valve, with a housing, an actuator displaceable in the housing in an actuating direction and an electric motor which acts via a spindle drive on the actuating element, characterized in that the motor (5) directly with a rotating element (8) of the spindle drive (8, 11, 8, 27) is connected.

2. Valve attachment according to claim 1, characterized in that the motor (5) is designed as a stepping motor.

3. Valve attachment according to claim 1 or 2, characterized in that the motor (5) is designed as a piezomotor.

4. Valve attachment according to one of claims 1 to 3, characterized in that the motor (5) has a first motor element (7) and a second motor element (6), between which viewed in the actuating direction, a piezoelectric element arrangement (21) is arranged.

5. Valve attachment according to claim 4, characterized in that the first motor element (7) and the second motor element (6) each have a diameter extension, wherein the piezoelectric element arrangement (21) is arranged in the region of the diameter enlargement.

6. Valve attachment according to claim 4 or 5, characterized in that the first motor element (7) as a rotor and the second motor element (6) are designed as a stator, wherein the two motor elements (7, 6) via a thread pairing (9, 10, 25, 26) communicate with each other.

7. Valve attachment according to one of claims 1 to 6, characterized in that the spindle drive has a non-rotating element (11, 27) which is supported on an end wall (4) of the housing (2).

8. Valve attachment according to claim 7, characterized in that the end wall (4) is displaceable.

9. Valve attachment according to claim 8, characterized in that the end wall forms part of a rotary handle (16).

10. Valve attachment according to one of claims 1 to 9, characterized in that the spindle drive (8, 11, 8, 27) is arranged in a region which, at least over part of its axial length from

Motor (5) is surrounded.

11. Valve attachment according to one of claims 1 to 10, characterized in that the motor (5) is controllable without wires.

12. Valve attachment according to claim 11, characterized in that the stator (6) of the motor (5) in the housing (2) is held stationary.

13. Valve attachment according to claim 11 or 12, characterized in that the rotor (7) and the stator (6) of the motor (5) are clamped together with a predetermined axial force.

14. Valve attachment according to claim 13, characterized in that a spring arrangement (23) acts in the axial direction on the motor (5).

15. Valve attachment according to claim 14, characterized in that the spring arrangement on the rotor (7) acting spring washer (23).

5 16. Valve attachment according to claim 15, characterized in that the spring disc (23) is supported on a in the housing (2) held locking ring.

17. Valve attachment according to claim 15, characterized in that the spring washer 0 (23) on a projection of the end wall (4) is supported.

18. Valve attachment according to one of claims 1 to 17, characterized in that the motor (5) has a decoupling means, 5, the axial forces acting on the actuating element from the valve, the rotor (7) keeps away.

19. Valve attachment according to claim 18, characterized in that the rotor (7) non-rotatably with a axially against the rotor (7) ver pushable driver (8) is in communication, which is in engagement with the actuating surface (14).