RU2300689C1 - Temperature control nozzle for valves - Google Patents

Abstract

FIELD: valving systems.

SUBSTANCE: nozzle comprises housing, sensitive member whose length depends on temperature, and driving member made for permitting movement in the direction of loading of the valve. The sensitive member is mounted inside the driving section between the housing and driving member. The driving section receives the fluid or air operated amplifier that converts the variations in the length of the sensitive member into the length of the driving section.

EFFECT: improved structure and enhanced sensitivity.

11 cl, 8 dwg

Description

The invention relates to a thermostatic nozzle for valves of heating or cooling units, comprising a housing with a sensitive element of variable working length, depending on the temperature, and a drive part made with the possibility of movement in the direction of action on the valve, and the sensitive element is located in the drive section between the housing and the drive detail.

Such a thermostatic nozzle is known, for example, from DE 10162608 A1. In this case, the thermostatic nozzle abuts against one end of the body at one end. The sensing element has a stretchable portion in the form of an internal bellows. This bellows covers the hole in which the drive part is inserted. When assembled, this actuating part abuts the valve follower. With increasing temperature acting on the sensing element, the drive part leaves the sensing element, while it presses on the valve follower, and the valve closes. With decreasing temperature, the volume of the sensing element decreases, and the valve follower driven in the opening direction returns the actuating part to the sensing element.

In accordance with the requirements for energy saving, most radiators are currently equipped with thermostatically controlled valves, and most of these valves require an appropriate thermostatic nozzle. Many of these nozzles also allow you to set a preset value. The position of the sensing element in the housing is changed, for example, using a rotary knob.

Temperature control in a room with radiators having such a nozzle is quite satisfactory, that is, the temperature that is set by the consumer or set in any other way is achieved with sufficient accuracy.

However, as observations show, with a constant set value, the temperature in the room throughout the year fluctuates within 1-2 ° C. This fluctuation is often not noticed, since in many rooms the set value is changed throughout the year. However, such fluctuation is unfavorable.

Therefore, in DE 4319814 C1, a thermostatic valve was proposed for heating radiators, in which the reciprocating movement of the sensing element is transmitted to the plunger. the valve not directly, but through an intermediate part with two threads directed oppositely and having a different pitch. Theoretically, this allows an increase in stroke. However, friction forces of large magnitude and a relatively high hysteresis associated with them arise, therefore, the regulatory properties are not satisfactory.

The basis of the invention is the task of creating a more advanced temperature-regulating nozzle.

In the case of a thermostatic nozzle of the above type, this problem is solved due to the fact that a change amplifier driven by a liquid or gas is placed in the drive section. This amplifier converts the change in the working length of the sensing element into a larger change in the length of the drive section.

With this design, the thermostatic nozzle responds to temperature changes with a steeper characteristic. If the length of the sensor element changes by x mm / ° C, then thanks to the expansion amplifier, the drive section is extended (or shortened) by y mm / ° C, with y = a · x and a> l. The gain can be, for example, in the range of 2 to 3. The characteristic of the sensitive element becomes much steeper, and the sensitive element does not need to be extended accordingly. If the corresponding steep characteristic is not needed, then an expansion amplifier is used to use a smaller sensor. Due to the use of liquid or gas as an amplifier, the additional losses arising, for example, due to friction forces, remain insignificant. In this case, you can use both liquid and gas.

The change amplifier should preferably have two interconnected pressure chambers of variable length. The chambers are filled with liquid having the ability to flow from one chamber to another. The cameras have different cross sections. This design gives the most effective form of corrector amplifier changes. If any force acts on the change amplifier, for example, due to the temperature expansion of the sensing element, then the pressure chamber with a large cross section (hereinafter we will call this camera a large camera) decreases, and the liquid inside it is forced into the pressure chamber with a smaller cross section ( we will call this camera a small camera). This displacement leads to a lengthening of the amplifier of changes, since due to different cross sections of the two pressure chambers, a kind of hydraulic converter is obtained. For example, if the cross-sectional ratio is 2.5, then displacing the liquid from the larger pressure chamber to a smaller one causes a corresponding gain of 2.5. Thus, if the sensor itself would cause an extension of 1 mm, then the expansion amplifier would result in a total extension of the drive section of 2.5 mm.

Preferably, at least one pressure chamber should be bounded by a bellows. Bellows are often used in sensitive elements of thermostats. They allow you to cover a certain space with a flexible and, thus, varying along the length of the wall. The bellows may be made of metal, plastic, or a combination of these materials. Plastic (rubber in this case is considered as a kind of plastic) can, for example, provide elasticity, and metal - tightness.

Preferably, the pressure chambers should be adjacent to each other. This provides constructive benefits. The length of the thermostatic nozzle in the drive direction can be reduced. Condensing the transition from one pressure chamber to another is also simplified structurally, since there is no need to bring out pipelines.

Certain advantages also arise if the pressure chambers are located one in the other. This reduces the need for additional structural length for the change amplifier.

Preferably, one of the pressure chambers should be made inside the sensing element. This further reduces the need for structural length.

It is particularly preferred that the sensing element forms a large pressure chamber. Thus, the space available inside the sensing element, which is filled with an expanding fluid when heated, is used as a larger pressure chamber.

The sensing element should preferably have an internal bellows in which the actuator stem is partially located. The rod abuts against the housing, and the sensing element can move in the housing in the direction of the drive. So, the sensing element is deployed in comparison with conventional thermostatic nozzles, that is, the actuating rod no longer protrudes in the direction of the valve. Moreover, the valve is now actuated by means of a movable sensing element, and a change amplifier or part of it can be provided between this element and the valve.

Preferably, the two pressure chambers should be connected to each other using a capillary tube. Capillary tube gives great opportunities in the design. In this case, it is not necessary to place the pressure chambers next to each other, although this is still possible.

Preferably, the pressure chamber with a smaller cross section should be limited by a liquid or gas impermeable membrane. Since in the case of a small pressure chamber, not significant changes in length are needed, but additional expansion is approximately in the range from 1 to 5 mm, the deviation that the membrane is capable of when applying pressure to it is sufficient.

Preferably, the liquid or gas impermeable membrane delimits from the end of the cylinder the cylinder in which the piston is located and acts on the piston. This reduces the burden on the membrane.

The invention is further described on the basis of preferred embodiments, the description is accompanied by drawings. The drawings show the following:

Figure 1 is a schematic view of a first structural form of a thermostatic nozzle.

Figure 2 - schematic representation of the principle of action of the amplifier changes.

Figure 3 is a second structural form of a thermostatic nozzle.

Figure 4 - the third structural form of thermostatic nozzle.

5 is a fourth structural form of a thermostatic nozzle with an enlarged extension element.

6 is a fifth structural form of a thermostatic nozzle.

The temperature-regulating nozzle 1 has a housing 2 in which the sensing element 3 is located. The sensing element 3 abuts against the end wall 4 of the housing 2. The end wall is made on the insert 5, which can be shifted in the axial direction with the handle 6 to set the temperature.

In the sensing element 3 there is a cavity 7 filled with a liquid or gas expanding when heated, the volume of the liquid or gas changes with temperature. On the inner side, the cavity 7 is bounded by a bellows 8. In the bellows 8 there is a drive rod 9, interacting with the stop 10. Inside the drive rod 9 is a spring 11.

The device of thermostatic nozzle 1 discussed above corresponds to the device of a conventional nozzle for a thermostatic valve. If the room temperature increases, then its increase affects the sensitive element 3. The fluid in the cavity 7 expands and displaces the actuator rod 9 down, as shown in FIG. The rod 9 by means of the stop 10 acts on the plunger 13 of the valve (the plunger is not shown in detail), and the valve closes.

Due to this, the supply of liquid coolant is reduced. If the temperature drops, because of this the volume of liquid in the cavity 7 decreases. The drive rod 9 can be introduced into the sensing element 3 to a greater extent, since the valve pusher 13 (the pusher is not shown in detail), as a rule, is loaded with force springs. The supply of liquid coolant increases. This process is repeated until a stable state is reached. So, the sensing element 3 produces, so to speak, proportional regulation.

In the claimed invention, the emphasis 10 directly on the valve pusher no longer acts. On the contrary, between the sensor 3 with the stop 10 and the drive part 12 acting on the valve pusher 13 shown schematically, there is a change amplifier 14. The change amplifier 14 shown in FIG. 1 is made as an additional part, that is, it can be retrofitted with an existing nozzle . Of course, instead of such a separate part, a rigidly integrated part can be used.

The change amplifier 14, which may be called an “expansion amplifier," has a first pressure chamber 15 radially bounded by a first bellows 16 and a second pressure chamber 17 radially bounded by a second bellows 18. To separate the pressure chambers 15, 17, there is shown in the drawing, the partition 19. In the partition 19 is made a connecting hole 20. In fact, you can do without a partition.

The partition 19 is fixed in the housing motionless thanks to the holder 22 and the support 21. A pusher acts on the drive part 12 with a force causing a decrease in the second pressure chamber 17.

The first pressure chamber 15 has a larger cross section than the second chamber 17. Therefore, the chamber 15 is called the large pressure chamber, while the second chamber 17 is called the small pressure chamber. However, in fact, the volumes of the two chambers 15, 17 may be the same. The difference in the cross section leads to the fact that when moving the fluid from the chamber 15 to the second chamber 17, the elongation of the chamber 17 exceeds the shortening of the chamber 15 resulting from the movement of the liquid. As mentioned above, the two pressure chambers differ only in order to better clarify the function of the "hydraulic converter". In the event that both pressure chambers 15, 17 are combined into one large chamber, the principle of operation does not change.

Let us explain this in more detail using Figure 2. Figure 2 in a schematic view shows a change amplifier 14 during two control phases. Identical parts are indicated by the same numbers as in FIG. 1. However, unlike in FIG. 1, both pressure chambers 15, 17 are not limited by bellows 16, 18, but by pistons 16a, 18a.

In this case, the large chamber 15 has a cross section A greater than the cross section B of the second chamber 17, for example, 2.5 times. Figure 2a shows the initial state. In order to compare this state with the subsequent ones, the upper line 23 and the lower line 24 are indicated in the drawing. The upper line 23 indicates the position of the upper edge of the piston 16a, and the lower line 24 indicates the position of the lower edge of the piston 18a at the moment when the change amplifier 14 is in the initial state condition.

If the temperature, for example, rises, then the drive rod 9 is squeezed out of the sensing element 3 (FIG. 1) and pushes the upper piston 16a down. The liquid is displaced from the first pressure chamber 15 into the second pressure chamber 17. Accordingly, the lower piston 18a and the pusher 13 (Fig. 1) also move, so the valve closes more. However, the second pressure chamber 17 in the drive direction expands more than the length of the first chamber 15 decreases in the axial direction, this difference is equal to the ratio between the cross sections of the chambers 15, 17. If the ratio between the cross sections of the first pressure chamber 15 and the second pressure chamber 17 is 5, then the upper piston 16a enters a distance a, the lower piston 18a extends a distance b = 5a.

Thus, at elevated temperatures, the change amplifier 14 increases the stroke of the sensing element. So, the characteristic of the thermostatic nozzle 1 becomes steeper, so that at an increasing temperature, the valve closes to a much greater extent compared to a conventional nozzle.

But the use of the change amplifier 14 shown in FIGS. 1 and 2 leads to the following drawback: the design size of the thermostatic nozzle 1 is significantly increased.

Figure 3 shows the modified design of the thermostatic nozzle, the same parts are indicated by the same numbers as in Figure 1.

In contrast to Figure 1, the change amplifier 14 in this case is formed by two bellows that are placed in each other. Thus, the bellows 16 covers the first pressure chamber 15. In the first pressure chamber 15 there is a partition 19 with a passage 20. In this case, the partition 19 is made in the form of an inverted bowl. A second bellows 18 is located under the partition 19, the second pressure chamber 17 being located between the partition 19 and the bellows 18. In this case, the bottom of the second bellows 18 acts on the drive part 12. The drive part 12 can be replaced by another element with a similar principle of operation, for example, the bottom second bellows 18.

In this case, the set position can be set by turning the knob 6.

The amplifier changes 14 allows you to construct a sensitive element 3 of smaller sizes. It should be assumed that the bellows can be reduced by half.

Figure 4 shows a slightly modified structural form, the designations of the parts are the same as in Figures 1 and 3. In this design, the first pressure chamber 15 forms the cavity 7 of the sensing element 3. The sensing element 3 in this case is located in the housing 2 in an inverted position, that is, the recess that the bellows 8 covers, faces the end wall 4 of the housing 2. A rod 25 is inserted into the bellows 8, abutting against the end wall 4. In the axial direction, that is, in the drive direction, the sensing element is fixed in the housing 2 but, for example, via the support 21.

From the closed end side of the sensing element 3, that is, from the side facing the opposite side of the bellows 8, a second pressure chamber 17 is made, which is covered by the bellows 18. The first pressure chamber 15 and the second pressure chamber 17 are connected to each other via a passage 20.

The second bellows 18 through the clip 26 acts on the drive part 12.

The functions of this structure are the same as those of the structure shown in FIGS. 1-3. However, in this case, the elongation of the amplifier changes 14 with increasing temperature occurs directly.

An increase in temperature is also associated with an increase in pressure in the first pressure chamber 15, that is, in the cavity 7 of the sensing element 3. This increase in pressure causes the liquid or gas from the cavity 7 through the passage 20 to enter the second pressure chamber 17. Since the second pressure head the chamber 17 has a significantly smaller cross-section than the first chamber 15, the second bellows 18 lengthens to a greater extent than the bellows 8 of the sensing element 3 is shortened. So, in general, a more significant elongation occurs with increasing temperature numerator 14 changes, consisting of the sensor element 3 and the bellows 18 in comparison with the lengthening of the sensor element 3.

Figure 5 shows a slightly modified design. This design basically corresponds to the design shown in FIG. 4. Accordingly, the same parts are denoted by the same numbers.

In this design, the pressure chamber 17 is limited not only by a bellows, but also by an elastic membrane 27, which is connected to the cylinder body 28 welded to the body of the sensing element 3. Welded connection 29 is shown schematically. The cylinder body 28 can also be glued to the casing 30 of the sensing element 3. In any case, the connection must be impermeable to the fluid located in the cavity 7 of the sensing element 3. Naturally, the membrane 27 must also be leakproof with respect to this fluid. Therefore, the membrane 27 is also designated as "impermeable membrane".

In the cage 26 there is a piston protrusion 31 which extends into the cylindrical cavity 32 of the cylinder body 28. An impermeable membrane 27 acts on the piston protrusion 31. Thus, if the pressure in the second pressure chamber 17 rises, the piston protrusion 31 exits the cylinder body 28, and the clip 26 with the drive part 12 is shifted down. In this case, it is advisable to coat either the piston protrusion 31 or the membrane 27 with an antifriction layer. To prevent diffusion through the membrane 27, on the side that faces the pressure chamber 17, a metal coating can also be applied to the membrane 27.

At the end of the casing 30 there is an opening 33 through which liquid from the first pressure chamber 15 can enter the second pressure chamber 17. The hole 33 forms a passage 20. Higher or lower pressure, which occurs in the second pressure chamber 17, leads to that the piston protrusion 31 to a greater or lesser extent comes out of the cylinder body 28.

Pressure chambers 15, 17 can be separated from each other by means of an elastic partition (not shown in the drawing), so that they can be filled with different liquids. Such a partition may overlap in the form of a dome, for example, hole 33.

Figure 6 shows another structural form, the designations of the parts are the same.

In this case, the pressure chambers 15, 17 are connected to each other using a capillary tube 36.

The pressure chamber 17, in turn, ends with a membrane 27, which acts on the piston protrusion 31. In this regard, this design corresponds to the design shown in Fig.5.

The invention was considered as an example of a thermostatic nozzle for a heating radiator. However, it can be used in a similar manner also in the low-temperature valve for chilled ceilings and the like heat exchangers. In this case, between the thermostatic nozzle 3 and the drive part 12, a reversible device is usually installed (not shown here).

Claims (11)

1. Thermostatic nozzle for valves of heating or cooling units, comprising a housing with a sensitive element of variable working length, depending on the temperature, and a drive part made with the possibility of movement in the direction of action on the valve, and the sensitive element is located in the drive section between the body and the drive part characterized in that in the drive section there is a change amplifier (14) driven by a liquid or gas and converting a change in the working length of the senses Yelnia element (3) in a greater change in length of the drive section. 2. Thermostatic nozzle according to claim 1, characterized in that the change amplifier (14) has two pressure chambers (15, 17) of variable length, filled with liquid or gas, which can flow from one pressure chamber to another, and the pressure chambers (15 , 17) have different cross sections. 3. Thermostatic nozzle according to claim 1, characterized in that at least the pressure chamber (15) is limited by a bellows (8, 16, 18). 4. Thermostatic nozzle according to claim 1, characterized in that the two pressure chambers (15, 17) are adjacent to each other. 5. Thermostatic nozzle according to claim 1, characterized in that the two pressure chambers (15, 17) are located one in the other. 6. Thermostatic nozzle according to claim 1, characterized in that one of the pressure chambers is made inside the sensing element (3). 7. Thermostatic nozzle according to claim 6, characterized in that the large pressure chamber (15) is formed by a sensitive element (3). 8. Thermostatic nozzle according to any one of claims 1 to 7, characterized in that the sensing element (3) has an internal bellows (8), in which the drive rod (25) partially rests against the housing (2, 4), and the sensing element (3) is arranged to move in the housing (2.4) in the direction of the drive. 9. Thermostatic nozzle according to any one of claims 1 to 7, characterized in that the pressure chambers (15, 17) are connected to each other by means of a capillary tube (36). 10. Thermostatic nozzle according to any one of claims 1 to 7, characterized in that the pressure chamber (17) with a smaller cross-sectional area is limited by a membrane (27) impermeable to liquid or gas. 11. Thermostatic nozzle according to claim 10, characterized in that the liquid / gas impermeable membrane (27) at the end limits the cylinder (32) in which the piston (31) is located, and the impermeable membrane (27) acts on the piston (31) .

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