GB2195442A

GB2195442A - Protection device for use with a thermostatic radiator valve

Info

Publication number: GB2195442A
Application number: GB08716131A
Authority: GB
Inventors: Allan Hornbeck Hansen; Erik Jacobsen; Preben Kristensen; Arne Markvart
Original assignee: Danfoss AS
Current assignee: Danfoss AS
Priority date: 1986-07-09
Filing date: 1987-07-09
Publication date: 1988-04-07
Anticipated expiration: 2007-07-09
Also published as: FR2607277B1; FR2607277A1; SE8702637D0; GB2195442B; JPH0792708B2; SE462730B; JPS6327907A; DK346487D0; DE3623003C1; CA1285253C; DK346487A; SE8702637L; GB8716131D0; DK166522B1

Abstract

To protect a capillary tube (4), extending between a sensor and a thermostatic valve (1) the tube is mounted in a protective tube (107) having a longitudinal slot (18) through which the capillary tube (4) can be inserted. Two mounting members (10, 113) serve respectively to locate one end (108) of the protective tube (107) at the thermostatic valve and the other end (112) at a surface (6) bounding the room. A second slotted tube (17) may be arranged within the outer tube (107). The capillary tube is retained when the slots are moved out of alignment. <IMAGE>

Description

SPECIFICATION Protection device for use with a thermostatic valve This invention reiates to a protection device for use with a thermostatic valve, namely an accessory for the thermostatic valve of a radiator, of which valve the operating element is connected to a temperature sensor by a capillary tube.

By reason of their small dimensions, capillary tubes are fragile components and are often damaged deliberately by kinking, severing and ripping out. Capillary tubes are particularly prone to be damaged in rooms used by young persons, such as in schools. If the capillary tube is destroyed, then the entire thermostatic actuator of the valve has to be replaced.

The invention is concerned with the problem of- protecting such conventional capillary tubes against damage.

The present invention provides a protection device for use with a thermostatic valve of a radiator, which valve has an operating element connected to a sensor by way of a capillary tube, the protection device comprising a protective tube having a slit along its length to enable a capillary tube to be introduced into the protective tube, and two mounting members for securing, respectively, one end of the protective tube to the thermostatic valve and the other end of the protective tube to a boundary surface of the room.

The above-mentioned problem is solved according to the invention by the protective tube having a slot along its length for introducing the capillary tube and by the two mounting members or holders for locating one end of the protective tube at the thermostatic valve and the other end at a surface bounding the room.

This protective tube prevents direct contact with the capillary tube and thus protects it from damage. The longitudinal slot permits the capillary tube to be introduced even though one end of the capillary tube is fixed to the operating element, for example a bellows, of the thermostatic actuator and the other end of the capillary tube is fixed to the temperature sensor. The holders secure the protective tube positively between the thermostatic valve and an adjacent wall or other room bounding surface so that even vigorous manipulation of the protective tube will not cause it to become displaced leading to damage of the capillary tube. By means of the sub-division into a protective tube and two holders, assembly is simple and can be undertaken on site.

With particular advantage, the protective tube contains a slotted internal tube. By turning the two slots relative to each other, one can ensure that the capillary tube cannot accidentally come out of the protective tube.

The internal tube is preferably of plastics material. Such a construction will be cheap. In addition, the plastics material forms an insulating intermediate layer. Since plastics tubes are practically always somewhat bowed, there will be frictional contact to secure the relative rotary position of the protective tube and internal tube.

In contrast, the protective tube can be of very strong material such as metal, particularly steel.

In many cases it is favourable for the protective tube to have a polygonal cross-section, especially a square cross-section. Such a cross-section gives the protective tube particular strength. In addition, the protective tube can be readily prevented from rotating.

To adapt to the prevailing spatial requirements of a particular installation, the protective tube can be cut to the appropriate length.

To allow installation without tools, however, it is advisable for the protective tube to consist of at least two telescopically displaceable tube sections.

In a preferred embodiment, the holders or mounting members each have at least one socket to receive the protective tube, a slot for introducing the capillary tube extending from the end of the socket that is outermost in use up to the rear end of the holder. The protective tube is therefore simply located by plugging it in after the capillary tube has been introduced through the slots of the sockets.

The holder at the thermostatic valve is desirably a holding or mounting ring that is pushed over the outside of the base of a thermostatic actuator and there locked in position.

In this way, conventional thermostatic valves can subsequently be provided with protection for the capillary tube. The production of the thermostatic actuators at the factory can continue without change in design. The arrangement of the mounting ring is such that, with the thermostatic actuator removed, the ring can readily be applied. If this separation of parts is not desired, then the holder for the protective tube can be formed directly on the base of a thermostatic actuator.

It is also favourable for the mounting ring to engage over a securing ring provided with a clamping screw, the securing ring being for attaching the base to the valve housing, and for the mounting ring to have at least one radial aperture through which the clamping screw is accessible. The mounting ring will not therefore impede securing of the valve unit to the valve housing.

In a preferred embodiment, the mounting ring has an axial socket which is disposed radially outwardly of continuous sections defining a ring and the radially outer wall of which socket contains the slot for introducing the capillary tube. This construction permits the slot to be provided whilst the form of a closed ring is retained.

In a further development, the mounting ring includes a radial socket which intersects the axial socket. While utilizing the same amount of space and the same slot it is possible to lead out the capillary tube not only axially but also radially..

It is recommended that the holder at the room bounding surface be a cover member with a peripheral side wall containing at least one recess which extends from the rear for further guidance of the capillary tube. Here, again, simple plugging in of the protective tube will suffice after the capillary tube has been introduced into the slot.

Cover strips of channel shape are also advantageous for covering the capillary tube running along the bounding -surface of the room.

One can therefore protect the capillary tube from destruction at all the accessible places where it would otherwise be susceptible to damage.

Protection devices constructed in accordance with the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 illustrates an axially extending protective tube running between a thermostatic actuator and a wall mounting member; Fig. 2 shows a protective tube extending radially from a thermostatic actuator; Fig. 3 is a side elevation of the arrangement of Fig. 1 but shows a modified form of wall mounting member; Fig. 4 is a section taken on the line A-A marked in Fig.3; Fig. 5 shows a modification of the Fig. 4 embodiment; Fig. 6 is a rear elevation of a mounting ring shown in Fig.3; Fig. 7 is a section taken on the line B-B shown in Fig. 6; Fig. 8 is a section showing the parts concerned in the mounting of a base on a valve housing; and Fig. 9 shows a protective tube of telescopic construction.

Referring now to the drawings, Fig. 1 shows a thermostatic actuator of a thermostatic valve, of which valve the valve housing connected- to a hot water radiator or connected in the vicinity of the radiator has been omitted for clarity. As usual, the thermostatic actuator comprises a base 2 for anti-rotational mounting and a knob 3 for setting a desired value. In the interior of the thermostatic actuator is an operating element which is connected to a temperature sensor 5 by way of a capillary tube 4. By way of example, the temperature sensor 5 contains a liquid/vapour mixture so that the temperature-dependent vapour pressure is effective to actuate the operating element. The sensor 5 can be secured to a wall 6 or to some other surface bounding a room.

A protective tube 7 serves to protect the capillary tube 4. One end 8 of the protective tube is inserted into a socket 9 on a mounting ring 10 pushed onto the base 2. The other end 11 of the tube is inserted in a socket 12 of a cover member 13 secured to the wall 6 by means of screws. The capillary tube 4 changes direction in the interior of the cover member 13 and emerges downwardly through a recess which corresponds to the illustrated recess 15 and runs from the rear of the cover member. The capillary tube is here covered by a cover strip 16 of channel shape which is likewise secured to the wall. Since the cover member 13 is secured to the wall 6 and the base 2 is secured to the valve housing, the protective tube 7 has a well-defined fixing position.

Fig. 2 shows that the capillary tube 4 and protective tube 7 can be brought out of the socket fitting 9 not only axially but also radially, as will be described in more detail later.

This manner of mounting is recommended when the nearest wall is not behind the valve but alongside it.

In Fig. 3, the thermostatic actuator 1 corresponds to that of Figs. 1 and 2 but the constructions of the protective tube and wall mounting member are modified. Identical parts are therefore referenced with the same numerals and equivalent parts carry reference numerals increased by 100.

An internal tube 17 of plastics material is located within the protective tube 107, the protective tube consisting of a rigid material, preferably steel or some other metal such as aluminium. The protective tube has a longitudinal slot 18 and the inner tube a longitudinal slot 18a. These slots serve to allow the insertion of the capillary tube 4. When both slots are turned with respect to each other, as is shown in Fig.4, the capillary tube 4 can no longer escape.

Fig. 5 shows that the protective tube 207 can have a square cross-section whilst the slots and the internal tube are the same as before.

A cover member 113 on the wall 6 has a central socket 112. In the same way as the cover member 13 has a slot 19 extending from the end face of the socket 12 to the rear of the cover member 13, the cover member 113 likewise has such a slot 119 for introducing the capillary tube 4. The extension of the capillary tube can again be protected by a shaped cover strip 116.

The construction of the mounting ring 10 will be explained with reference to Figs. 3, 6, 7 and 8. The socket 9 consists of an axial socket portion 20 and a radial socket portion 21, the two socket portions intersecting.

Here, again, there is a slot 22 on the outside extending from the end of the axial socket portion 20 to the rear of the mounting ring 10 to permit the insertion of the capillary tube 4.

Radially inwardly, the axial socket fitting 20 is bounded by continuous sections 23 arranged in a ring. The slot 22 therefore penetrates into the cavity of the socket only.

The base 2 is secured on the barrel 24 of a valve housing 25 by means of a securing device K. The securing device K comprises a securing ring 26 which holds resilient base sections 27 in the vicinity of the barrel 24 and, in a radial rib 28, has a clamping screw 29 having a conical tip 30 engaging a conical side wall 31 of an annular groove 32. By tightening the clamping screw 29, the resilient base sections 27 are forced against the end face of the valve housing 25.

The mounting ring 10 is pushed over this arrangement in such a manner that one of the axial recesses 34, 35 or 36 receives the radial rib 28 whereas the remainder of the securing ring 26 is closely surrounded by the inner periphery 37 of the mounting ring 10. When pushing on the mounting ring 10, resilient locking lugs 38, 39 and 40 engage behing the peripheral edge 41 of a base rim 42, so that the mounting ring 10 is locked in place. Each recess 34 to 36 is associated with a respective radial aperture 43 through which an operating tool, for example a hexagonal key, can be introduced for turning the clamping screws 29.

The asssembly of the protection device takes place as follows. Appropriate lengths of the protective tube 107 and the internal tube 17 are cut off. The capillary tube 4 is then introduced through the longitudinal slot 19 into the inner tube 17. A further length of the capillary tube is introduced in the protective tube 107 through the longitudinal slot 18. The inner tube 1 7 is then pushed into the protective tube 107. Thereupon, the two slots 18 and 19 are mutually offset.

The end 108 is now introduced into the axial socket portion 20. Finally the end 111 is introduced into the socket 112 at the same time as the thermostatic actuator is fitted over the valve housing 25. The capillary tube which leaves through the cover member 113 and is to be located on the wall 6 is then covered by the shaped cover strip 116.

Fig. 9 shows a modified form of protective tube 307 in which, to simplify obtaining the right length of tube, a first tube 44 and a second tube 45 are telescopically interengaged. These tubes likewise have a longitudinal slot and are forcibly pushed together until the correct length is obtained. In this case, the sockets at the mounting ring and cover mernber will need to have different dimensions from each other to match the ends of the tube.

Claims

1. A protection device for use with a thermostatic valve of a radiator, which valve has an operating element connected to a sensor by way of a capillary tube, the protection device comprising a protective tube having a slit along its length to enable a capillary tube to be introduced into the protective tube, and two mounting members for securing, respectively, one end of the protective tube to the thermostatic valve and the other end of the protective tube to a boundary surface of the room.

2. A protection device as claimed in claim 1, wherein a slit inner tube is provided within the protective tube.

3. A protection device as claimed in claim 2, wherein the inner tube is of plastics material.

4. A protection device as claimed in any one of claims 1 to 3, wherein the protective tube is a metal tube.

5. A protection device as claimed in claim 4, wherein the protective tube is a steel tube.

6. A protection device as claimed in any preceding claim, wherein the protective tube is of polygonal cross-section.

7. A protection device as claimed in claim 6, wherein the protective tube is of square cross-section.

8. A protection device as claimed in any preceding claim, wherein the protective tube comprises at least two telescopically arranged tube portions.

9. A protection device as claimed in any preceding claim, wherein each mounting member has at least one socket to receive the protective tube.

10. A protection device as claimed in claim 9, wherein in each mounting member a slot extends from the end of the at least one socket to the rear of the mounting member to allow the insertion of the capillary tube.

11. A protection device as claimed in any preceding claim, wherein the mounting member for securing one end of the tube on a thermostatic valve is a mounting ring pushable over the base of a thermostatic actuator of the valve and there lockable in position.

12. A protection device as claimed in claim 11, wherein the mounting ring is arranged to engage over a securing ring of the thermostatic actuator and has at least one radially arranged aperture to allow access to a clamping screw of the securing ring for attaching the base of the actuator to a valve housing.

13. A protection device as claimed in claim 11 or claim 12, wherein the mounting ring comprises an axially arranged socket disposed radially outwards of continuous sections forming a ring and has the slot for introducing the capillary tube in its radially outer wall.

14. A protection device as claimed in claim 13, wherein the mounting ring includes a radially arranged socket which intersects the axially aranged socket.

15. A protection device as claimed in any preceding claim, wherein the mounting member for the room bounding surface is a cover member with a peripheral side wall containing at least one'recess in the rearmost (when in use) part of the mounting member for further guiding the capillary tube.

16. A protection device as claimed in any preceding claim, wherein cover strips of channel shape are provided for covering the capillary tube where it runs along the room bounding surface.

17. A protection device for use with a thermostatic valve of a radiator, which valve has an operating element connected to a sensor by way of a capillary tube, the protection device being substantially as herein described with reference to, and as illustrated by, Figure 1 of the accompanying drawings.

18. A protection device for use with a thermostatic valve of a radiator, which valve has an operating element connected to a sensor by way of a capillary tube, the protection device being substantially as herein described with reference to, and as illustrated by, Figure 2 of the accompanying drawings.

19. A protection device for use with a thermostatic valve of a radiator, which valve has an operating element connected to a sensor by way of a capillary tube, the protection device being substantially as herein described with reference to, and as illustrated by, Figures 3, 4, 6, 7 and 8 of the accompanying drawings.

20. A protection device as claimed in claim 17, 18 or 19, but modified substantially as herein described with reference to, and as illustrated by, Figure 4 of the accompanying drawings.

21. A protection device as claimed in claim 17, 18, 19 or 20, but modified substantially as herein described with reference to, and as illustrated by, Figure 9 of the accompanying drawings.

22. A thermostatic radiator valve provided with a protection device as claimed in any preceding claim.