GB1564047A

GB1564047A - Thermostatic regulating valve

Info

Publication number: GB1564047A
Application number: GB157177A
Authority: GB
Original assignee: Danfoss AS
Current assignee: Danfoss AS
Priority date: 1976-01-30
Filing date: 1977-01-14
Publication date: 1980-04-02
Also published as: DK35477A; DE2603461A1; DK151149B; SE7700862L; DE2603461C3; CA1080181A; FR2339798B1; DK151149C; DE2603461B2; FR2339798A1

Description

(54) IMPROVEMENTS IN AND RELATING TO A THERMOSTATIC REGULATING VALVE (71) We, DANFLOS A/S., a Danish Company, of DK-6430 Nordborg, Denmark, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: The invention relates to a thermostatic regulating valve especially for radiators.

Thermostatic radiator valves are used to control the room temperature not only in private houses or apartments but also in public buildings such as schools, hospitals.

offices etc. to conserve energy and thereby save costs. However, careful handling and economic setting of the regulating valves is not always ensured, particularly in public buildings. The result of this is frequent damage of the regulating valves and a higher energy consumption.

The present invention provides a thermostatic regulating valve comprising a thermostatic actuator unit and a valve housing, the actuator unit comprising a control knob for setting a desired temperature value, the knob being rotatable relative to a connecting union of the actuator unit which union connects the unit to the valve housing, wherein a safety device surrounds a skirt of the knob and the connecting union and can be clamped thereto to prevent rotation of the knob relative to the union.

The clamped safety device blocks the knob against rotation so that, once a desired temperature value has been set, it cannot be readily changed by unauthorised persons. At the same time, it can strengthen the connection between the knob and the connecting union as well as between the latter and the valve housing. A regulating valve that is already installed can subsequently be equipped with the safety device without requiring any constructional change to that valve. Further, theft of the thermostatic unit is made more difficult when the safety device is emploved.

The safety device can also be used to clamp the connecting union to the valve housing. A separate clamping device for that purpose is then unnecessary.

It is favourable if the safety device comprises a circumferentially incomplete safety ring. The assembly and manufacture of this is simple.

Preferably, the inner peripheral surface of the safety device and the outer peripheral surface of the skirt of the control knob are provided with interengageable means for preventing relative rotation between the device and the knob. This increases the security with which the knob is locked. The said means on the knob can be formed by the Iongitudinal fluting usually provided to improve its gripping surface.

Tt is preferred also if means on the safety device are interengageable with means on the connecting union to prevent relative rotation between the device and the union.

Further, the safety device may be clamped bv a clamping strap, means-preferably a clamping screw-being provided for adjust inq the clamping force exerted by the strap.

This may be the same or a similar but peripherally somewhat larger clamping strap as that usually used for connecting the connect ina union to the valve housing.

it is particularly favourable if part of the connecting union overlaps a connecting neck of the valve housing, that part having longitudinal slits to define separate axial tongues, the clamping strap surrounding the said part of the safety device. In this way the clamp ill(r strap at the same time increases the clamping force of the connecting union on the neck of the valve housing.

As an alternative to using a clamping strap, the safety ring may be provided with flanges at each of its ends, the flanges being in confronting relationship and comprising apertures for introducing a clamping screw.

Preferably, the clamping screw is a socketheaded screw. This can be loosened only with the aid of a special tool, a key for socket-headed screws, and thereby increases the security of the knob against unauthorised turning and against theft.

It is particularly favourable if the safety ring comprises a transversely extending section between the sections overlapping the skirt of the knob and the connecting bunion.

This transverse section increases the stiffness of the safety ring against spreading even after the clamping screw(s) have been loosened. At the same time, it offers space for the formation of apertures which permit air circulation for the withdrawal of heat or for the passage of a capillary tube for connecting a remote sensor if the gap formed between the ends of the safety ring is inadequate for this purpose.

For the purpose of the passage of the capillary tube it is, however, also possible for the transverse section of the safety ring to be provided with a hole which is preferably an enlargement of the gap formed between the ends of the safety ring.

A thermostatic radiator valve constructed in accordance with the invention will now be described, with reference to the accompanying drawing, by way of example only, where sn: Fig. 1 is a cross-section through a known thermostatic radiator valve; Fig. 2 is a part-perspective view of the radiator regulating valve constructed in accordance with the invention Fig. 3 is a part-sectional view of the valve shown in Fig. 2 with parts removed, Fig. 4 is an end elevation, partly in section, of the valve shown in Fig. 2, Fig. 5 is an end elevation of part of the valve. shown in Figs. 2 and 3, and Fig. 6 is a section through the valve part shown in Fig. 5 taken on the line A-A in Fig. 5.

Referring to the accompanying drawings, Fig. 1 shows a known regulating valve having a housing 1 with an inlet nipple 2, a valve seat 3 and an outlet nipple 4. The housing is provided with a neck 5 in which a cover 6 is screwed and on which a thermostatic actuator unit indicated generally at 7 is retained with the aid of a clamping device 8.

The clamping device 8 surrounds a connecting nipple 22 (made of resilient material, e.g.

plastics) of the unit 7 which is mounted over and overlaps the neck 5. The unit 7 comprises a control knob 9 which surrounds a temperature sensor 10 and a thermostatic operating element in the form of a bellows 11. An adjustable spring 12 acts against the vapour pressure existing in the operating element 11 and its counterbearing 13 can be axially displaced, by turning the knob 9, to set the desired value of temperature. A plate 14 of the operating element 11 carries a tappet 15 which frictionally engages a valve spindle 16.

The valve spindle 16 is passed through a sealing arrangement in the form of an '0' ring gland 17 accommodated in a screw-threaded sleeve 18 which is screwed into the cover 6.

The valve spindle 16 acts on a shaft-like extension 19 of a valve closure member 20.

A return spring 21 presses on a collar of the extension 19 so that the valve spindle 16 abuts the tappet 15.

Referring now to Figs. 2 to 6 which illustrate a thermostatic regulating valve constructed in accordance with the invention, it will be seen that this valve is basically the same in construction as that illustrated in Fig. 1. However it includes a safety ring, indicated generally at 23, of comparatively stiff slightly elastic material, preferably plastics or Silumin, which has a portion 24 overlapping the skirt of the knob 9, and a portion 25 overlapping the connecting nipple 22. The ring 23 is not complete in the circumferential sense and has a radially extending gap formed between its two circumferential end portions. The portion 25 of the safety ring 23 is surrounded by a clamping strap 26 of which the radially outwardly directed end portions 27, 28 are held together by a socketheaded screw 29 under prestress.

On the outside, the knob 9 is provided with a spined gripping portion 30 formed by elongated axial teeth (or flutes) which engage with complementarily formed part 31 on the inner surface of the portion 24 of the ring 23. The inside surface of the portion 25 possesses a formation of ribs 32 and a groove 33 which engage with complementary formed slots 34 and a rib 35 provided on the end portion of the connecting nipple 22 (see Fig. 4). Consequently, when the clamping strap 26 is tightened, a connection preventing rotation also exists between the knob 9 and the connecting nipple 22. Once a desired temperature value has been set, it can therefore be altered, by turnin the knob 9, only after loosening the socket-headed screw 29 to allow the safetv rinz 23 to expand slightly so that the formations 30 and 31 are disenzaged.

The clamping strap 26, when tightened, not only serves to hold the safety ring 23 closed thereby preventing relative rotation between the knob 9 relative to the nipple 22.

but also serves to damn connecting nipple 22 tishtlv on the neck 5. Clamping of the niDple 22 is facilitated bv the slots 34 which allows the end portion of the nipple (which because of the presence of the slots is in the form of a number of axially extending tongues 36, see Fig. 3) to flex inwards.

Preferably. a loneitudinal rib (not shown) is additionally provided on the outside of the neck 5 to engage in a slot 34- of the connecting nipple 22 and secure it against rotation even when the socket-headed screw 29 is loosened and the clamping strap 26 is open.

A substantially conical portion 37-of the safety ring 23 interconnecting- the portions 24 and 25 of the safety rinz 23 serves not only to adapt the safety ring 23 for use with different external diameters of the knob 9 and connecting nipple 22, but also, more importantly, to stiffen the safety ring 23 against expansion. The same clamping strap 26 can be used for different diameters of the knob 9 and nipple 22.

After removal or loosening of the clamping strap 26, bending open of the safety ring 23 to an extent where the entire unit 7 can be withdrawn from the neck 5 requires the use of a special tool by reason of the stiffness of the safety ring 23, so that it is not readily possible to remove the unit 7. In addition, the safety ring 23 when tightened contributes tto the bending strength of the connecting nipple 22, thereby avoiding the danger of breaking off of the unit 7 even with careless treatment such as that primarily occurring in public buildings, particularly schools.

Radially extending sections 38 at the free end of the safety ring section 25 axially locate the clamping strap 26. Aperlures 39 in the central section 37 of the ring 23 permit air circulation for the withdrawal of heat.

The clamping strap 26 and the flange sections 38 can be omitted if the circumferential end portions of the safety ring 23 is provided with radially extending flanges 40 to 43 (shown in broken lines in Figs. 5 and 6) having apertures for receiving clamping screws, preferably socket-headed screws. Further, in this case, it would be possible to omit the flanges 41 and 42 and to use only the flanges 40 and 43.

The safety ring 23 may be provided with an axial bore 44 (Fig. 4) in its conical portion 37, preferably formed as a circular enlargement in the region of the safety ring gap.

The bore 44 may be used to accommodate a capillary tube which connects the operating element 11 to a remotely disposed temperature sensor. With appropriate dimensioning it is, however, also possible to pass the capillary tube through one of the apertures 39.

The bore 44 is therefore indicated in Fig. 4 as an alternative in broken lines.

WHAT WE CLAIM IS:- 1. A thermostatic regulating valve comprising a thermostatic actuator unit and a valve housing, the actuator unit comprising a control knob for setting a desired temperature value, the knob being rotatable relative to a connecting union of the actuator unit which union connects the unit to the valve housing, wherein a safety device surrounds a skirt of the knob and the connecting union and can be clamped thereto to prevent rotation of the knob relative to the union.

2. A valve as claimed in claim 1, in which the safety device can also be used to clamp the connecting union to the valve housing.

3. A valve as claimed in claim 1 or claim 2, in which the safety device comprises a circumferentially incomplete ring.

4. A valve as claimed in any one of claims 1 to 3, in which the inner peripheral surface of the safety device and the outer peripheral surface of the skirt of the control knob are provided with interengageable means for preventing relative rotation between the device and the knob.

5. A valve as claimed in claim 4, in which means on the safety device are interengageable with means on the connecting union to prevent relative rotation between the device and the union.

6. A valve as claimed in any one of claims 1 to 5, in which the safety device is clamped by a clamping strap, means being provided for adjusting the clamping force exerted by the strap.

7. A valve as claimed in claim 6, in which the adjusting means is a screw.

8. A valve as claimed in claim 6 or claim 7, in which part of the connecting union over Japs a connecting neck of the valve housing, that part having longitudinal slits to define separate axial tongues, the clamping strap surrounding the said part of the safety device.

9. A valve as claimed in claim 3, or claim 4 or claim 5 when appendant to claim 3, in which the safety ring is provided with flanges at each of its ends, the flanges being in confronting relationship and comprising apertures for introducing a clamping screw.

10. A valve as claimed in claim 7, claim 8 when appendant to claim 7, or claim 9, in which the screw is a socket-headed screw.

11. A valve as claimed in claim 3 or any one of claims 4 to 10 when appendant to claim 3, in which the ring comprises a transversely extending section between the sections overlapping the skirt of the knob and the connecting union.

12. A valve as claimed in claim 10, in which the transverse section has apertures.

13. A valve as claimed in claim 11 or claim 12, in which the transverse section is provided with a hole, for the passage of a capillary tube.

14. A valve as claimed in claim 13, in which the hole is formed as an enlargement of the gap formed between the ends of the ring.

15. A thermostatic regulating valve sub- stantially as hereinbefore described with reference to and as illustrated by the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. different external diameters of the knob 9 and connecting nipple 22, but also, more importantly, to stiffen the safety ring 23 against expansion. The same clamping strap 26 can be used for different diameters of the knob 9 and nipple 22. After removal or loosening of the clamping strap 26, bending open of the safety ring 23 to an extent where the entire unit 7 can be withdrawn from the neck 5 requires the use of a special tool by reason of the stiffness of the safety ring 23, so that it is not readily possible to remove the unit 7. In addition, the safety ring 23 when tightened contributes tto the bending strength of the connecting nipple 22, thereby avoiding the danger of breaking off of the unit 7 even with careless treatment such as that primarily occurring in public buildings, particularly schools. Radially extending sections 38 at the free end of the safety ring section 25 axially locate the clamping strap 26. Aperlures 39 in the central section 37 of the ring 23 permit air circulation for the withdrawal of heat. The clamping strap 26 and the flange sections 38 can be omitted if the circumferential end portions of the safety ring 23 is provided with radially extending flanges 40 to 43 (shown in broken lines in Figs. 5 and 6) having apertures for receiving clamping screws, preferably socket-headed screws. Further, in this case, it would be possible to omit the flanges 41 and 42 and to use only the flanges 40 and 43. The safety ring 23 may be provided with an axial bore 44 (Fig. 4) in its conical portion 37, preferably formed as a circular enlargement in the region of the safety ring gap. The bore 44 may be used to accommodate a capillary tube which connects the operating element 11 to a remotely disposed temperature sensor. With appropriate dimensioning it is, however, also possible to pass the capillary tube through one of the apertures 39. The bore 44 is therefore indicated in Fig. 4 as an alternative in broken lines. WHAT WE CLAIM IS:-

1. A thermostatic regulating valve comprising a thermostatic actuator unit and a valve housing, the actuator unit comprising a control knob for setting a desired temperature value, the knob being rotatable relative to a connecting union of the actuator unit which union connects the unit to the valve housing, wherein a safety device surrounds a skirt of the knob and the connecting union and can be clamped thereto to prevent rotation of the knob relative to the union.

7. A valve as claimed in claim 6, in which the adjusting means is a screw.