CA1332828C - Temperature responsive valve - Google Patents
Temperature responsive valveInfo
- Publication number
- CA1332828C CA1332828C CA 596338 CA596338A CA1332828C CA 1332828 C CA1332828 C CA 1332828C CA 596338 CA596338 CA 596338 CA 596338 A CA596338 A CA 596338A CA 1332828 C CA1332828 C CA 1332828C
- Authority
- CA
- Canada
- Prior art keywords
- valve
- helical spring
- closure member
- housing
- bearing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D19/00—Details
- F24D19/0002—Means for connecting central heating radiators to circulation pipes
- F24D19/0009—In a two pipe system
- F24D19/0012—Comprising regulation means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/002—Actuating devices; Operating means; Releasing devices actuated by temperature variation
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Temperature-Responsive Valves (AREA)
Abstract
A temperature responsive valve has a housing (1) in which there is supported a first helical spring (17) with the effect of memorizing its shape and for closing and opening the valve. A temperature in-sensitive second helical spring (20) in the housing prestresses the first helical spring (17), To achieve a small diameter and substan-tially unhindered throughflow when the valve is open, the housing (1) has a valve seat (8) and a valve closure member (9). The first helical spring (17) is supported by one end at the housing (1) and by the other end at the side of the valve closure member (9) remote from the valve seat (8) whereas the second helical spring (20) is supported by one end at the housing (1) radially beyond the valve seat (8) and by the other end on the side of the valve closure member (9) facing the valve seat (8). The second helical spring acts against the closing force of the first helical spring (17) and the valve closure member (9) comprises apertures (13) from the interior of the first helical spring (17) to an annular chamber (21) within the second helical spring (20) and radially beyond the valve seat (8).
Description
DANFOSS A/S, DK-6430 NORDBORC
Temperature responsive valve The invention relates to a temperature responsive valve comprising a housing through which a fluid can pass and in which there are arranged co-axlally a first helical spring which is expansible and contractable depending on the fluid temperature, especially a spring with the effect of memorising the shape, and which is supported at the housing and brings about the closing and opening of the valve, and a substant-ially temperature insensitive second helical spring for pre-stressing the first helical spring.
In a known valve of this kind, the temperature sensitive helical spring ls of metal having the effect of memorislng the shape, a so-called SME metal (SME = shape memory effect). Its one end lies against a radially inwardly pro~ecting collar of a throughflow passage in the housing and its other end lies against a plate having a central tapped hole in which a headed screw is screwed. One end of the second helical spring is supported at the head of the screw by way of a second plate which is seated on the shark of the screw by having a central hole, whilst the other end is likewise supported on the collar in the through_ flcw passage. With a high temperature, the fluid flows through the convolutions of the temperature sensitive helical spring. However, if the temperature falls, the convolutions of the temperature sensitive coil spring become closer to each other and thereby throttle the flow against the force of the second spring. As the temperature continues to drop, the convolutions finally lie against each other so that the f ~ -2-flow is completely blocked. Upon a rise in temperature, the temper-ature sensitive coil spring expands agalnst the force of the second spring, so that the flow is started again. The two helical sprlngs are co-axially seated within each other because the collar on the inside of the temperature sensitive spring is angled axially inwardly and then radially again and the second helical spring is supported on the radlally angled inner marginal sectlon of the collar. To ensure a fluid tight abutment when the convolutions of the temperature sensitive helical spring lie against each other, the spring wire is provided with an elastic covering or with a radially pro~ecting sealing strip.
In this construction, the temperature sensitive helical spring has a large external diameter and, without the expensive additional covering or sealing strip, there is an inadequate seal when the convolutions of the temperature sensitive helical spring have contracted to lie against each other. If one were to reduce the diameter of the temperature sensitive helical spring to enable the valve to be built into a pipe having a comparatively small internal diameter, e.g. into the return conduit of a radiator of a heating installation, this would excessively reduce the free flow section when the valve is open.
The invention i9 ba~ed on the problem of providing a valve of the aforementioned kind of which the external diameter can be kept compar-atively small and which does not markedly influence the flow in the open condition when built into the return pipe of a heating install-atlon to llmlt the return flow temperature.
_ 3 The invention relates to a temperature-responsive valve comprising a housing through which, in use, fluid passes and in which there are arranged, substantially co-axially with each other, a first helical spring which, in use, expands and contracts depending on the temperature of fluid passing through the valve, acts against the housing and is arranged to bring about the closing and opening of the valve, and a second, substantially temperature-insensitive, helical spring for biasing the first helical spring. A valve seat and a valve closure member are provided within the housing and the temperature-responsive first helical spring has one end acting against the housing and the other end acting against that side of the valve closure member remote from the valve seat. The second helical spring has one end acting against the housing at a location radially outwards of the valve closure member, and the other end acting against that side of the valve closure member facing the valve seat and acts against the force of the first helical spring tending to close the valve. At least one aperture is provided in the valve closure member establishing communication between the interior of the first helical spring and an annular chamber, within the second helical spring, located radially outwards of the valve seat.
In this construction, the fluid need not flow between the convolutions of the helical spring in the open condition of the valve. Instead, it can for the most part flow through the interior of the springs. The valve diameter can therefore be kept very small. Consequently, the valve can also be built into pipes of comparatively small diameter, and even as an afterthought, for example into the return pipe of a central heating radiator for limiting the temperature of the return flow. In the aforementioned known valve, however, one must leave an annular space outside the temperature responsive coil spring corresponding to the maximum flow section. Further, since the diameter of the temperature sensitive helical spring in the case of the known valve cannot be markedly reduced if an adequate flow section is to be available between the spring convolutions in the case of a short spring and because the second coil spring is disposed within the A
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1332~
temperature sensitive coil spring, the known valve has a comparatively large external diameter. In addition, in the known case the second coil spring impedes the throughflow because, as the temperature sensitive spring expands, the second spring contracts and correspond-ingly reduces the free flow section between its spring convolutions.
In a development of the valve according to the invention, the valve clo3ure member may comprise an elastic sealing disc on the side facing the valve seat. This ensures an efficient seal in the closed condition of the valve. Such a sealing disc is not only simple to apply but also leaves the surface of the temperature responsive coil spring free so that the latter makes direct contact with the fluid and very rapidly responds to temperature fluctuations.
Preferably, the valve closure member is substantially pot-shaped and its apertures extend radially through the circumferential wall of the valve closure member over its entire axial length and part of the base of the valve closure member lying on the side of the valve seat. This gives a large free flow section in the valve closure member radially beyond the valve seat, it being possible for the temperat~re sensitive helical spring to be arranged on the outside or inside of the wall of the pot and be guided thereby.
Further, the end of the first and/or second helical spring remote from the valve closure member can be supported at an axially ad~ustable counter-bearing. This permits the characteristic of the valve to be ;
set, compensation Or manufacturing tolerances, and manual over-riding of the set closlng or opening point because ad~ustment of the counter-bearing not only changes the pre-stressing of the closure member but also its spacing from the valve seat.
The housing should have an aperture for passing through a setting element by means Or which the adjustable counter-bearing of the first coil spring is ad~ustable. In this construction, the valve can be easily set from outside the valve housing without removing the valve from a pipe into which it is built.
If the counter-bearing of the second helical spring comprises the valve seat and this counter-bearing is axially adju~table, it wi~ll fuLfil a dual function.
The same problem can be solved by an alternative solution for a temper-ature responsive valve of the aforementioned kind comprising a housing through which a fluid can pass and in which there are arranged co-axially a metal actuating element, particularly one with the effect of memorlsing the shape, which is expansible and contractable depending on the fluid temperature and brings about the closing and opening of the valve and a substantially temperature insensitive helical spring for pre-stressing the actuating element. In said alternative solution, the housing comprises a valve seat and a valve closure member, the actuating element is a pin of which one end is supported at the housing and the other end acts on the valve closure member in the closing J
direction, and the helical spring acts on the valve closure member opposite to the actuating element and the actuating element passes axially through the hellcal spring. The pin can have a very much smaller diameter than a coil spring so that it will not markedly influence the free flow section and possibly only the single helical spring will be traversed by fluid. Although the pin must be compara-tively long to achieve a sufficient ad~ustment path, the structural length will nevertheless be comparatively short because the pin passes through the helical spring.
Alternatively, there can be a third solution in which the housing comprises a valve seat and a valve closure member, the actuating element is a wire of which one end section acts on the valve closure member in the closlng direction and the other end section is stationary relatively to the housing, and the helical spring acts on the valve closure member oppositely to the wire and the wire passes axially through the helical spring. In this third solution, the same advan-tages are obtained as for the second solution.
The valve closure member may be mounted cardanically. This ensures that it will always lie completely against the valve seat when the valve is closed.
If one ensures that the valve closure member is hollow cylindrical and passes through the valve seat, that the one radial side of a radially J
outwardly pro~ecting flange of the valve closure member faces the valve seat and ls provlded with an elastic sealing disc, and that one end section of the actuating element is received in the hollow space of the valve closure member, one can use a stlll longer pin or bar with a correspondingly longer actuating stroke per unit change in temperature.
This second solution can be developed in that the valve closure member comprises an axial bore with a step against the edge of which a hinge member lies closely from the outlet side of the valve under the pre-stressing effect of the helical spring, the one end section of the actuating element passing through the bore being secured to the hinge member. This brings about cardanlc mounting of the valve member in a simple manner. With particular advantage, the actuating element in this constructlon may be of SME metal whlch contracts axlally upon heating and expands upon cooling, the hellcal springloading theactuat-ing element in tension. The actuatlng element can therefore be very thin, preferably a wire, because the danger of kinklng as would occur when the actuating element is loaded in compression is avoided.
Accordingly, the diameter of the entire valve can be still further reduced.
Instead of the last mentioned development, it is also possible to make thehCusing substantially pot-shaped and to provlde it with axial apertures in the base radially beyond a hollow cylindrical base exten-sion which receives and axially supports the other end section of the --8-- .
actuatlng element. Thls readily permlts an elongate constructlon of the actuating element wlth a correspondlngly hlgher sensltlvlty.
In the second solution, the end of the helical sprlng that ls not supported at the valve closure member can also be supported at an axlally ad~ustable counte~r-bearlng so that the same advantages are obtalned as in the flrst solution.
The same applles if the counter-bearlng of the hellcal spring contalns the valve seat ln the case of the second solutlon.
The end sectlon of the actuating element received in the hollow cylind-rlcal valve closure member may be supported at an axlally ad~ustable counter-bearing. In this way, one likewise obtalns a possibillty of adapting the characteristlc llne of the valve to a partlcular appllc-ation.
Preferred examples of the invention and its developments wlll now be descrlbed wlth reference to the drawing ln which:
Fig. 1 is an en~arged axial sectlon through a first embodiment, Fig. 2 is a side elevation of the Fig. 1 example substantially in actual slze, 13~2828 Fig. 3 is a plan vlew of the Fig. 4 closure member, ig. 4 i9 an enlarged side elevation of the closure member used in the examples of Flgs. 1 to 4, lg. 5 is an axial section of the closure member taken on the line V-V in Flg. 4, ig. 6 ls a side elevatlon of the Flg. 4 closure member substant-ially in actual size, ig. 7 is an axial section through a second embodiment to a larger scale, Fig. 8 is a side elevation of the Fig. 7 example substantially in actual slze, Flg. 9 ls an enlarged axial section through a third example, Flgs. lO and 11 are respectively a plan view and slde elevation of an ad~ustable counter-bearing in the Flg. 9 example, Figs. 12 and 13 are respectively a side elevatlon and plan view of the closure member of the Flg. 9 valve, Flg. 14 is a side elevation of the Fig. 9 valve substantially in actual size, -lo-- 1332828 ig. 15 is an axial section through a fourth embodiment to an enlarged scale, ig. 16 is a side elevation of the Fig. 15 valve substantlally in actual size, ig. 17 is an enlarged axial section through a fifth embodiment, ig. 18 is a side elevation of the Fig. 17 valve substantially in actual size, ig. 19 is an enlarged axial section through a sixth embodiment, ig. 20 is a side elevation of the Fig. 19 valve substantially in actual size, ig. 21 is an enlarged axial section through a sixth embodiment, ig. 22 is a cross-section through the embodiment of Fig. 21, Fig. 23 is a side elevation of the Fig. 21 valve substantially in actual slze, Fig. 24 is an enlarged axial section through a seventh embodiment, Fig. 25 is a side elevation of the valve of Fig. 24 substantially in actual size, 13~28 Flg. 26 is an enlarged axlal section through an eight embodiment, ig. 27 is a cro3s-section through an eccentric bolt of the Fig. 26 valve, ig. 28 is a side elevation of the Fig. 26 valve substantially in actual size, ig. 29 i3 an enlarged axial section through a ninth embodiment, ig. 30 is a side elevation of the Fig. 29 valve ~ubstantially in actual size, Fig. 31 is an enlarged axial section through a tenth embodiment, Fig. 32 ls a slde elevation of the Flg. 31 valve substantially in actual size, Fig. 33 is an axial section through an eleventh embodiment to an enlarged scale, Fig. 34 is half a plan view of the Fig. 33 valve, Fig. 35 is a side elevation of the Fig. 33 valve substantially in actual size, Fig. 36 is an enlarged axial section through a twelfth embodiment, Flg. 37 is a slde elevatlon of the Fig. 36 valve substantlally ln actual size, ig. 38 is an enlarged axial section through a thirteenth embodiment, and ig. 39 is a side elevatlon of the Flg. 39 valve substantlally in actual size.
The example of Figs. 1 and 2 comprises a hollow cylindrical housing 1 with a conical external screwthread 2 for screwing into a fitting in a return conduit of a radiator of a hot water heating installation and an annular flange 3 behind which a cap nut of the fitting is brought to abut as the valve is being built into the return conduit.
The direction ln which flow takes place through the valve i9 indicated by arrows 4.
On the inlet side, a screwthreaded ring 5 with a hexagonal exterior 6 is screwed lnto the lnternal screwthread 7 of the housing 1. The axlally inner end face of the screwthreaded rlng 5 forms a valve seat 8 for a valve closure member 9. On lts side faclng the valve seat 8, the closure member 9 ha~ an elastic sealing disc 10, for example of rubber, in the form of an annular disc which surrounds the neck of a substantially mushroom-shaped pro~ection 11 facing the valve seat 8 and is supported at an annular shoulder 12 of the valve closure member 9. The valve closure member 9 l~ sub~tantially pot-shaped and provided wlth apertures 13 which pass radially through the circumferential wall 14 of the valve closure member 9 over its entire axial length and part of the base 15 of the valve closure member 9 lying on the ~ide of the valve seat 8. The circumferential wall 14 i~ further provided with a radially outwardly pro~ecting annular flange 16, on the slde of which remote from the valve seat 8 there is supported one end of a temper-ature responslve helical spring 17 of which the other end iQ ~upported at an inner shoulder 18 of the hou~ing 1 forming the axial inner end of an internal hexagon 19 at the outlet end of hou~ing 1. The hellcal sprlng 17 consists of a metal having the effect of memorising the shape, also known a3 an SME metal where the letter~ SME stand for shape memory effect. It could be a copper alloy, for example CuZnAl.
Thi~ material has the property of considerably expanding on heating and contracting again on cooling.
On the other side of the annular shoulder 16, there is supported one end of a second helical spring 20 of which the other end is supported radially beyond the valve seat 8 at the axially inner end face of the screwthreaded rlng 5. The internal diameter of the helical spring 20 ls larger than the external dlameter of the clrcumferential wall 14 of the valve closure member 9, so that an an~ular chamber 21 remains between the helical sprlng 20 and the valve closure member 9 for the passage of the hot water when the valve ls open.
13328~8 If the valve is bullt into the return conduit of a radiator, the convolutions of the temperature sensitive helical spring 17 will lie closely ~uxtaposed when the valve is open for as long as the water temperature is below a lower limiting value at which the force of the helical spring 17 is less than that of the helical spring 20. Upon a rise in temperature, the force of spring 17 increases until it finally exceeds the force of spring 20 and presses the valve closure member 9 against the valve seat 8. In the now closed position of the valve, the water in the radiator and in the return conduit can cool off because the supply of further hot water is blocked. In this closed position, the convolutions of spring 17 lie apart so that the water makes large area contact with the spring 17.
After the water has cooled off sufficiently, the coil spring 17 will axially contract again so that the valve closure member 9 is lifted off the valve seat 8 under the force of the spring 20 and the flow is freed again until the water temperature in the housing 1 again falls below the lower limiting value.
8y reason Or using the shape memory effect metal for the hellcal spring 17, even a sllght change in temperature of, for example, 5 to 10C will enable the entire strdke of the valve closure member 9 to be executed so that the valve will be very sensitive in responding to temperature changes. The high speed of response results from the low mass of the hellcal spring 17 and hence its low thermal capacity.
Further, the large surface area of spring 17 contributes to a reduction 1~328~8 ln the response delay.
The use of the SME metal for spring 17 has the additional advantage that the distance-temperature characteristic of spring 17 is independ-ent of the static pressure of the water, in contrast with an actuating element having a temperature sensitive expansible material such as steam, a liquid or wax in an expansible container.
The screwsthreaded ring 5 serves as an adjustable counter-bearing for the helical spring 20. By adjusting the ring 5, it ls therefore possible not only to select the pre-stressing of the helical spring 20 but also the spacing between the sealing disc 10 and the valve seat 8 in the open conditlon of the valve so that on the one hand the hysteresisf the valve is reduced and on the other hand it is possible to set different opening and closing temperatures.
In the open condition of the valve, the water flows practically unhind-ered through the screwthreaded ring 5, the annular chamber 21 and partially also through the annular chamber disposed outside the spring 20, through the apertures 13, the interior chamber of the valve closure member 9 and the interior of the helical sprlng 17 without the through-flow being markedly hindered. The internal diameter of the housing 1 can therefore be approximately the same as the external diameter of the helical springs 17 and 20. It is only necessary to maintain a certain amount of play between the external circumference of the helical springs 17 and 20 and the inside of the housing 1 in order to 13~2828 permit movement of springs 17 and 20 and of the valve closure member 9 within the housing 1. With a comparatively large flow section, the valve can therefore nevertheless have a small external diameter so that it can be built into even existing return conduits and convention-al fittings having a small internal diameter.
In the return conduit, the valve serves as an automatic return temper-ature limiting device. In this way one can obtain a low temperature for the return water. This leads to a higher efficiency in boilers which are cooled by the flue gas. Upon starting the heating install-ation, losses are avoided if there has been a preceding drop in the desired temperature, e.g. during-night time. Losses are also avoided if the desired value of the preceding temperature is increased.
Further, lo~ses are avoided as a result of ventilating a heated room, without reducing the preceding temperature.
The use of the elastically resilient seallng disc 10 ensures that the valve will seal tightly and the helical spring 17 need not be subjected to high excess temperatures with a correspondingly high closing force which could result in larger hysteresis.
The example of Figs. 7 and 8 differs from that of Figs. 1 to 6 substan-tially only in that the housing 1a has thinner walls, does not have a screwthread and is provided at the inlet end with a conical flange 22, and the valve ~eat 8 is in the form of an annular disc at a counter-bearing 5a which is fixed with respect to the housing. The shoulder 18 of housing 1a serving as a counter-bearing for the helical spring 17 can be pushed axially inwardly by means of a setting apparatus in order to set the free path between the counter-bearings 5a and 18 for the helical springs 17 and 20 or their pre-stressing and so that the opening and closing temperatures of the valve can be set to the desired values. In this valve there is again a small external diameter as shown in Fig. 8, so that it can be easily inserted in a conventional return conduit and secured with a cap nut.
In the example of Fig~. 9 to 14, the housing 1b is provided on the inlet side with a cylindrical external screwthread 2a and on the outlet side with an internal screwthread 23 and an external hexagon for connecting it into the return conduit. Further, it has a radially pro~ecting nipple 24 which bounds an aperture in the housing 1b and has an internal screwthread 25 into which there i9 screwed a set screw 26 which i9 sealed from the nipple 24 by means of an 0 ring 27 and a conical point 28. The conical point 28 of set screw 26 lies against a complementary conical external surface 29 of a counter-bearing 30 for the temperature sensitive helical spring 17 on the side of the counter-bearing 30 remote from the spring 17. Further, the housing 1b contains a substantially star-s~aped guide 31 with a hub 32 coaxial with the axis of the housing 1b. In the hub 32, the counter-bearing 30 is mounted for axial displacement with a cylindrical extension 33 on the side of the counter-bearing 30 remote from the helical spring 17.
Radially extending webs 34 of the guide 31 connected to the wall of 133282~
the houslng deflne between each other axlal apertures 35 for the throughflow of the water. On its side facing the helical spring 17, the counter-bearing 30 is substantially pot-shaped and is provided in its circumferential wall 36 with radially and axially extending aper-tures 37 which also partially go through the base 38 of counter-bearing 30. One end of the temperature responsive helical spring 17 is supported at the base 38 of counter-bearing 30. The other end of spring 17 is supported at the base 15 of the valve closure member 9a which i9 of the same construction as the valve closure member 9 except that its flange 16 has been omitted and, instead, the internal diameter of the still substantially pot-shaped valve closure member 9a is increased, so that the helical spring 17 finds space within the circum-ferential wall 14. The valve seat 8a is in the form of an edge.
In this example, the water can flow through not only within but also outslde the temperature responsive helical spring 17 when the valve is open. Even with the valve closed practically the entire surface of the temperature responsive helical spring 17 is in contact with the water, so that the response delay or time constant of spring 17 with respect to a change in temperature is still less. Nevertheless, one obtains a comparatively small external diameter for the valve with a sufficiently free flow section. Ad~ustment of the counter-bearing 30 is possible with the aid of the set screw 26 and thus an ad~usting possibility additional to that achieved by the screwthreaded ring 5, ad~ustment of the set screw 26 being possible from the outside even when the valve is built into the return conduit. Further, the set J
screw 26 can be screwed in so deeply that the valve ls tightly closed and the thermostatic function is eliminated.
The construction of valve seat 8a in the form of an edge gives a larger surface pres~ure and thus a better sealing effect with the same pressing force by the valve closure member 9a as in the preceding examples.
Insofar that the example of Figs. 15 and 16 uses the same components as in the preceding examples, the same reference numerals are used.
The main difference i9 that the valve is one with an angled housing 1c and, in addition to the screwthreaded ring 5, a securing ring 39 is provided in the housing 1c. Further, the apertures 13a do not extend over the entire length of the circumferential wall 14 of the valve cloqure member 9.
The example of Figs. 17 and 18 differs from that of Figs. 15 and 16 only in that the screwthreaded ring 5 has the same valve seat 8 as the Fig. 1 example and the securing ring 39 is omitted.
The example of Fig~. 19 and 20 likewise has an angled housing 1d.
Whereas the counter-bearing 5b for the helical spring 20 i~ fixed with respect to the housing, the counter-bearing 30a for the helical spring 17 is also in this case ad~ustable. For this purpose, the counter-bearing 30a has an external screwthread 40 with which it engages in an internal screwthread 41 in a sub~tantially pot-shape cylindrical extension 42 of housing ld that is axially in line with the helical springs. The counter-bearing 30a is sealed against the housing exten-sion 42 with the aid of two 0 rings 43. Between the 0 rings 43, the counter-bearing 30a has an externally extending row of depressions 44 of which the intermediate walls form a gear ring. These depression~
44 are accessible to a setting element (not shown), for example a screwdriver, by way of an elongate aperture 24b of housing 1d so as to turn the counter-bearing 30a and thereby ad~ust it in the axial direct-ion.
The Figs. 21 to 23 example substantially corresponds to that of Figs.
19 and 20 except that here the housing 1e is provided with the nipple 24 and as a setting element there is a worm 26a of which the screw-thread 45 engages in tooth gaps 44a of a gear ring surrounding the counter-bearing 30b. The worm 26a is provided with a collar 46 abutt-ing a bushing 47 which i8 screwed into the screwthread 25 of nipple 24 and has an external screwthread for securing the position of the worm 26a.
By turning the worm 26a, the counter-bearing 30b is also turned and ad~usted in its axial direction by reason of its screwthread 40 engag-ing in the screwthread 41.
The example of Figs. 24 and 25 again comprises an angled housing 1f and, as far as the inlet side is concerned, substantially corresponds to the examplè of Fig. 19 and, as far as ad~u~tment of the counter-bearing 30 is concerned, corresponds substantially to the example of 13328~8 Figs. 9 to 14 except that the nipple 24 extends obliquely to the circumferential wall of the housing 1f and perpendicular to the conical external surface 29 of the counter-bearing 30. The setscrew 26b does not have a conical tip but has a flat at its end for lying against the exterior surface 29 of the counter-bearing 30. The counter-bearing 30 is displacably mounted with an extension 33 in a guide bore 32a. In thi~ embodiment, the counter-bearing 30 of the spring 17 is again ad~ustable in the axial direction of spring 17 by turning the setscrew 26b.
The example of Figs. 26 to 28 substantially corresponds to that of Figs. 24 and 25 except that the setting element 26c has an eccentric 48 of which the cross-section ls illustrated in Fig. 28 and which lies against the side of the counter-bearing 30c remote from the valve closure member 9a, the counter-bearing being displaceablein the housing 1g. The setting element 26c is on the one hand rotatably mounted in the bushing 4~ and on the other hand rotatably mounted by an axial extension pin 49 in a bore of the housing 1g. By turning the setting element 26c, the counter-bearing 30c is likewise ad~usted in the present example.
The example of Figs. 29 and 30 substantially corresponds to that of Figs. 24 and 25 except that the nipple 24 is again perpendicular to the inlet section of the housing 1h and the setscrew 26 is provided with a conical tip 28 as in the example of Fig. 9. The operation is therefore the same as in the example of Fig. 19.
In the example of Figs. 31 and 32, which likewise comprises an angled housing 1i, the inlet portion likewise corresponds to that of Fig. 19.
On the other hand, the cylindrical axial extension 33 of the counter-bearing 30d is sealingly guided with the aid of an O ring 50 in a guide bore 32b which is coaxial to the helical springs 17 and 20, the extension 33 eng~g~ng in -an end depression 51 of the set screw 26d in the houslng extension or in the nipple 24 and the housing extension 24 being coaxial to the helical springs 17, 20. Further, by means of a shank 52 reduced relatively to its screwthreaded section, the set screw 26d passes through a coaxial bore 53 in a cap nut 54 which is screwed on to the nipple 24 and serves to secure the set screw 26d axially. In this example, ad~ustment of the counter-bearing 30d in the housing 1i coaxial to its inlet section or the helical springs 17, 20 is brought about by turning the set screw 26d.
In the example of Figs. 33 to 35, the temperature responsive actuating element 17a is a thin cylindrical wire. The material of the wire 17a is preferably an SME metal of a nickle-titanium alloy activated so that the wire 17a contracts on heating and expands on cooling. This alloy can, however, also be designed so that it expands on heating and contracts on cooling. Compared with a Cu-Zn-Al alloy, it has the advantage of a longer change in length depending on the temperature.
A very thln wire will therefore suffice. The wire 17a has its one end section received in an axially throughgoing bore 55 of the valve closure member 9b and its other end section is secured to a sleeve 56 which is coaxial with the housing 1~, projects axially from the housing 1~ and is secured with its inner end in a coaxial bore 57 of the 133282~
housing 1~ so that the sleeve 56 forms a counter-bearing fixed with -respect to the housing for the wire 17a clamped therein.
The counter-bearing 5b for the helical spring 20 at the same time brings about centering of the valve closure member 9b while maintaining its radial play for the axial displacement of the valve closure member 9b.
The end section of wire 17a received in the bore 55 of the closure member 9b is tightly clamped in a ~oint member 58 with a conical sealing face. The ~oint member 58 is sealingly held from the outlet side of the valve against an edge 59 of a step in the bore under the pressure of the temperature insensitive helical spring 20 which act~
by way of the sealing discs 10 on the annular shoulder 21 of a radially outwardly pro~ecting flange 68 of the valve closure member 9b, whilst the valve closure member 9b is lifted off the valve seat 8a. With the valve 8a, 9b closed, the ~oint member 58 lies against the edge 59 under the tensile force of the wire 17a which contracts on heating and expands on cooling, so that the ~oint member 58 lies tightly against the edge 59 under all operating conditions and prevents the passage of fluid but at the same time cardanically supports the valve closure member 9b. The cardanic bearing ensures that the valve closure member 9b will not assume an oblique position relatively to the valve seat 8a but will always lie against the entire valve seat 8a when it is closed.
The housing 1~ is provided with axial passages 60 which are radially o inwardly open towards the bore 57 and leave a passage for the warm water externally of the coil spring 20. With a radial spacing from the valve seat 8a, the coil spring 20 lies on the inside of the valve seat at the sealing disc 10.
With the valve 8a, 9b open, the warm water can flow on the one hand through radial bores 61 in the sleeve 56, the bore 55, radial bores 62 of the valve closure member 9b and the intermediate spaces between the convolutions of the hellcal spring 20 and on the other hand through the passages 60.
When the wire 17a cools off and expands, the valve 8a, 9b is opened under the pressure of spring 20.
The helical ~pring 20 i9 SO dimensioned that its convolutions will, even with the valve 8a, 9b closed, have a sufficient spacing for the throughflow of the warm water.
In this example, the warm water can again flow through the housing 1~
practically unhindered when the valve 8a, 9b is open, it again being possible to have a very small external diameter for the housing 1~
because the temperature sensitive actuating element 17a likewise has a very small diameter and, by reason of its considerable length, never-theless ensures a long actuating strdke over a very small temperature range.
In the example of Figs. 36 and 37, the actuating element 17b is an elongate pin of SME metal which expands on heating and contracts on cooling and which i8 considerably longer than the housing lk of the valve. Here, again, the valve closure member 9c is hollow cylindrical, passes through the valve seat 8a and pro~ects from the housing lk to a large extent. The temperature sensitive pin 17b pro~ects with its one end section into the bore 55 of the valve closure member 9c and with its other end section into a hollow cylindrical base extension 63 of the otherwise substantially pot-shaped housing lk of which the base is provided with axial apertures 64 further radially beyond the extension 63.
The counter-bearing 5c for the temperature insensitive helical spring 20 is in the form of a cap nut which is screwed into the internal screwthread 7 of the housing lk and is provided with lateral apertures 65 for the passage of the hot water.
The pin 17b is supported on the one hand at the base of the extension 63 and on the ~ther hand at the set screw 26 which is screwed into that end of the valve closure member 9c that pro~ects from the housing lk, the set screw abutting the end of the pin 17b. In this example, the valve stroke or pre-stressing of the helical spring 20 is likewise adJustable by turning the set screw 26 and, if desired, by turning the counter-bearing 5c.
The example of Figs. 38 and 39 differs from that of Figs. 36 and 37 only in that the set screw 26 i9 omitted and the valve closure member 9d is instead closed at the end pro~ecting from the housing 9k.
Temperature responsive valve The invention relates to a temperature responsive valve comprising a housing through which a fluid can pass and in which there are arranged co-axlally a first helical spring which is expansible and contractable depending on the fluid temperature, especially a spring with the effect of memorising the shape, and which is supported at the housing and brings about the closing and opening of the valve, and a substant-ially temperature insensitive second helical spring for pre-stressing the first helical spring.
In a known valve of this kind, the temperature sensitive helical spring ls of metal having the effect of memorislng the shape, a so-called SME metal (SME = shape memory effect). Its one end lies against a radially inwardly pro~ecting collar of a throughflow passage in the housing and its other end lies against a plate having a central tapped hole in which a headed screw is screwed. One end of the second helical spring is supported at the head of the screw by way of a second plate which is seated on the shark of the screw by having a central hole, whilst the other end is likewise supported on the collar in the through_ flcw passage. With a high temperature, the fluid flows through the convolutions of the temperature sensitive helical spring. However, if the temperature falls, the convolutions of the temperature sensitive coil spring become closer to each other and thereby throttle the flow against the force of the second spring. As the temperature continues to drop, the convolutions finally lie against each other so that the f ~ -2-flow is completely blocked. Upon a rise in temperature, the temper-ature sensitive coil spring expands agalnst the force of the second spring, so that the flow is started again. The two helical sprlngs are co-axially seated within each other because the collar on the inside of the temperature sensitive spring is angled axially inwardly and then radially again and the second helical spring is supported on the radlally angled inner marginal sectlon of the collar. To ensure a fluid tight abutment when the convolutions of the temperature sensitive helical spring lie against each other, the spring wire is provided with an elastic covering or with a radially pro~ecting sealing strip.
In this construction, the temperature sensitive helical spring has a large external diameter and, without the expensive additional covering or sealing strip, there is an inadequate seal when the convolutions of the temperature sensitive helical spring have contracted to lie against each other. If one were to reduce the diameter of the temperature sensitive helical spring to enable the valve to be built into a pipe having a comparatively small internal diameter, e.g. into the return conduit of a radiator of a heating installation, this would excessively reduce the free flow section when the valve is open.
The invention i9 ba~ed on the problem of providing a valve of the aforementioned kind of which the external diameter can be kept compar-atively small and which does not markedly influence the flow in the open condition when built into the return pipe of a heating install-atlon to llmlt the return flow temperature.
_ 3 The invention relates to a temperature-responsive valve comprising a housing through which, in use, fluid passes and in which there are arranged, substantially co-axially with each other, a first helical spring which, in use, expands and contracts depending on the temperature of fluid passing through the valve, acts against the housing and is arranged to bring about the closing and opening of the valve, and a second, substantially temperature-insensitive, helical spring for biasing the first helical spring. A valve seat and a valve closure member are provided within the housing and the temperature-responsive first helical spring has one end acting against the housing and the other end acting against that side of the valve closure member remote from the valve seat. The second helical spring has one end acting against the housing at a location radially outwards of the valve closure member, and the other end acting against that side of the valve closure member facing the valve seat and acts against the force of the first helical spring tending to close the valve. At least one aperture is provided in the valve closure member establishing communication between the interior of the first helical spring and an annular chamber, within the second helical spring, located radially outwards of the valve seat.
In this construction, the fluid need not flow between the convolutions of the helical spring in the open condition of the valve. Instead, it can for the most part flow through the interior of the springs. The valve diameter can therefore be kept very small. Consequently, the valve can also be built into pipes of comparatively small diameter, and even as an afterthought, for example into the return pipe of a central heating radiator for limiting the temperature of the return flow. In the aforementioned known valve, however, one must leave an annular space outside the temperature responsive coil spring corresponding to the maximum flow section. Further, since the diameter of the temperature sensitive helical spring in the case of the known valve cannot be markedly reduced if an adequate flow section is to be available between the spring convolutions in the case of a short spring and because the second coil spring is disposed within the A
rn/
1332~
temperature sensitive coil spring, the known valve has a comparatively large external diameter. In addition, in the known case the second coil spring impedes the throughflow because, as the temperature sensitive spring expands, the second spring contracts and correspond-ingly reduces the free flow section between its spring convolutions.
In a development of the valve according to the invention, the valve clo3ure member may comprise an elastic sealing disc on the side facing the valve seat. This ensures an efficient seal in the closed condition of the valve. Such a sealing disc is not only simple to apply but also leaves the surface of the temperature responsive coil spring free so that the latter makes direct contact with the fluid and very rapidly responds to temperature fluctuations.
Preferably, the valve closure member is substantially pot-shaped and its apertures extend radially through the circumferential wall of the valve closure member over its entire axial length and part of the base of the valve closure member lying on the side of the valve seat. This gives a large free flow section in the valve closure member radially beyond the valve seat, it being possible for the temperat~re sensitive helical spring to be arranged on the outside or inside of the wall of the pot and be guided thereby.
Further, the end of the first and/or second helical spring remote from the valve closure member can be supported at an axially ad~ustable counter-bearing. This permits the characteristic of the valve to be ;
set, compensation Or manufacturing tolerances, and manual over-riding of the set closlng or opening point because ad~ustment of the counter-bearing not only changes the pre-stressing of the closure member but also its spacing from the valve seat.
The housing should have an aperture for passing through a setting element by means Or which the adjustable counter-bearing of the first coil spring is ad~ustable. In this construction, the valve can be easily set from outside the valve housing without removing the valve from a pipe into which it is built.
If the counter-bearing of the second helical spring comprises the valve seat and this counter-bearing is axially adju~table, it wi~ll fuLfil a dual function.
The same problem can be solved by an alternative solution for a temper-ature responsive valve of the aforementioned kind comprising a housing through which a fluid can pass and in which there are arranged co-axially a metal actuating element, particularly one with the effect of memorlsing the shape, which is expansible and contractable depending on the fluid temperature and brings about the closing and opening of the valve and a substantially temperature insensitive helical spring for pre-stressing the actuating element. In said alternative solution, the housing comprises a valve seat and a valve closure member, the actuating element is a pin of which one end is supported at the housing and the other end acts on the valve closure member in the closing J
direction, and the helical spring acts on the valve closure member opposite to the actuating element and the actuating element passes axially through the hellcal spring. The pin can have a very much smaller diameter than a coil spring so that it will not markedly influence the free flow section and possibly only the single helical spring will be traversed by fluid. Although the pin must be compara-tively long to achieve a sufficient ad~ustment path, the structural length will nevertheless be comparatively short because the pin passes through the helical spring.
Alternatively, there can be a third solution in which the housing comprises a valve seat and a valve closure member, the actuating element is a wire of which one end section acts on the valve closure member in the closlng direction and the other end section is stationary relatively to the housing, and the helical spring acts on the valve closure member oppositely to the wire and the wire passes axially through the helical spring. In this third solution, the same advan-tages are obtained as for the second solution.
The valve closure member may be mounted cardanically. This ensures that it will always lie completely against the valve seat when the valve is closed.
If one ensures that the valve closure member is hollow cylindrical and passes through the valve seat, that the one radial side of a radially J
outwardly pro~ecting flange of the valve closure member faces the valve seat and ls provlded with an elastic sealing disc, and that one end section of the actuating element is received in the hollow space of the valve closure member, one can use a stlll longer pin or bar with a correspondingly longer actuating stroke per unit change in temperature.
This second solution can be developed in that the valve closure member comprises an axial bore with a step against the edge of which a hinge member lies closely from the outlet side of the valve under the pre-stressing effect of the helical spring, the one end section of the actuating element passing through the bore being secured to the hinge member. This brings about cardanlc mounting of the valve member in a simple manner. With particular advantage, the actuating element in this constructlon may be of SME metal whlch contracts axlally upon heating and expands upon cooling, the hellcal springloading theactuat-ing element in tension. The actuatlng element can therefore be very thin, preferably a wire, because the danger of kinklng as would occur when the actuating element is loaded in compression is avoided.
Accordingly, the diameter of the entire valve can be still further reduced.
Instead of the last mentioned development, it is also possible to make thehCusing substantially pot-shaped and to provlde it with axial apertures in the base radially beyond a hollow cylindrical base exten-sion which receives and axially supports the other end section of the --8-- .
actuatlng element. Thls readily permlts an elongate constructlon of the actuating element wlth a correspondlngly hlgher sensltlvlty.
In the second solution, the end of the helical sprlng that ls not supported at the valve closure member can also be supported at an axlally ad~ustable counte~r-bearlng so that the same advantages are obtalned as in the flrst solution.
The same applles if the counter-bearlng of the hellcal spring contalns the valve seat ln the case of the second solutlon.
The end sectlon of the actuating element received in the hollow cylind-rlcal valve closure member may be supported at an axlally ad~ustable counter-bearing. In this way, one likewise obtalns a possibillty of adapting the characteristlc llne of the valve to a partlcular appllc-ation.
Preferred examples of the invention and its developments wlll now be descrlbed wlth reference to the drawing ln which:
Fig. 1 is an en~arged axial sectlon through a first embodiment, Fig. 2 is a side elevation of the Fig. 1 example substantially in actual slze, 13~2828 Fig. 3 is a plan vlew of the Fig. 4 closure member, ig. 4 i9 an enlarged side elevation of the closure member used in the examples of Flgs. 1 to 4, lg. 5 is an axial section of the closure member taken on the line V-V in Flg. 4, ig. 6 ls a side elevatlon of the Flg. 4 closure member substant-ially in actual size, ig. 7 is an axial section through a second embodiment to a larger scale, Fig. 8 is a side elevation of the Fig. 7 example substantially in actual slze, Flg. 9 ls an enlarged axial section through a third example, Flgs. lO and 11 are respectively a plan view and slde elevation of an ad~ustable counter-bearing in the Flg. 9 example, Figs. 12 and 13 are respectively a side elevatlon and plan view of the closure member of the Flg. 9 valve, Flg. 14 is a side elevation of the Fig. 9 valve substantially in actual size, -lo-- 1332828 ig. 15 is an axial section through a fourth embodiment to an enlarged scale, ig. 16 is a side elevation of the Fig. 15 valve substantlally in actual size, ig. 17 is an enlarged axial section through a fifth embodiment, ig. 18 is a side elevation of the Fig. 17 valve substantially in actual size, ig. 19 is an enlarged axial section through a sixth embodiment, ig. 20 is a side elevation of the Fig. 19 valve substantially in actual size, ig. 21 is an enlarged axial section through a sixth embodiment, ig. 22 is a cross-section through the embodiment of Fig. 21, Fig. 23 is a side elevation of the Fig. 21 valve substantially in actual slze, Fig. 24 is an enlarged axial section through a seventh embodiment, Fig. 25 is a side elevation of the valve of Fig. 24 substantially in actual size, 13~28 Flg. 26 is an enlarged axlal section through an eight embodiment, ig. 27 is a cro3s-section through an eccentric bolt of the Fig. 26 valve, ig. 28 is a side elevation of the Fig. 26 valve substantially in actual size, ig. 29 i3 an enlarged axial section through a ninth embodiment, ig. 30 is a side elevation of the Fig. 29 valve ~ubstantially in actual size, Fig. 31 is an enlarged axial section through a tenth embodiment, Fig. 32 ls a slde elevation of the Flg. 31 valve substantially in actual size, Fig. 33 is an axial section through an eleventh embodiment to an enlarged scale, Fig. 34 is half a plan view of the Fig. 33 valve, Fig. 35 is a side elevation of the Fig. 33 valve substantially in actual size, Fig. 36 is an enlarged axial section through a twelfth embodiment, Flg. 37 is a slde elevatlon of the Fig. 36 valve substantlally ln actual size, ig. 38 is an enlarged axial section through a thirteenth embodiment, and ig. 39 is a side elevatlon of the Flg. 39 valve substantlally in actual size.
The example of Figs. 1 and 2 comprises a hollow cylindrical housing 1 with a conical external screwthread 2 for screwing into a fitting in a return conduit of a radiator of a hot water heating installation and an annular flange 3 behind which a cap nut of the fitting is brought to abut as the valve is being built into the return conduit.
The direction ln which flow takes place through the valve i9 indicated by arrows 4.
On the inlet side, a screwthreaded ring 5 with a hexagonal exterior 6 is screwed lnto the lnternal screwthread 7 of the housing 1. The axlally inner end face of the screwthreaded rlng 5 forms a valve seat 8 for a valve closure member 9. On lts side faclng the valve seat 8, the closure member 9 ha~ an elastic sealing disc 10, for example of rubber, in the form of an annular disc which surrounds the neck of a substantially mushroom-shaped pro~ection 11 facing the valve seat 8 and is supported at an annular shoulder 12 of the valve closure member 9. The valve closure member 9 l~ sub~tantially pot-shaped and provided wlth apertures 13 which pass radially through the circumferential wall 14 of the valve closure member 9 over its entire axial length and part of the base 15 of the valve closure member 9 lying on the ~ide of the valve seat 8. The circumferential wall 14 i~ further provided with a radially outwardly pro~ecting annular flange 16, on the slde of which remote from the valve seat 8 there is supported one end of a temper-ature responslve helical spring 17 of which the other end iQ ~upported at an inner shoulder 18 of the hou~ing 1 forming the axial inner end of an internal hexagon 19 at the outlet end of hou~ing 1. The hellcal sprlng 17 consists of a metal having the effect of memorising the shape, also known a3 an SME metal where the letter~ SME stand for shape memory effect. It could be a copper alloy, for example CuZnAl.
Thi~ material has the property of considerably expanding on heating and contracting again on cooling.
On the other side of the annular shoulder 16, there is supported one end of a second helical spring 20 of which the other end is supported radially beyond the valve seat 8 at the axially inner end face of the screwthreaded rlng 5. The internal diameter of the helical spring 20 ls larger than the external dlameter of the clrcumferential wall 14 of the valve closure member 9, so that an an~ular chamber 21 remains between the helical sprlng 20 and the valve closure member 9 for the passage of the hot water when the valve ls open.
13328~8 If the valve is bullt into the return conduit of a radiator, the convolutions of the temperature sensitive helical spring 17 will lie closely ~uxtaposed when the valve is open for as long as the water temperature is below a lower limiting value at which the force of the helical spring 17 is less than that of the helical spring 20. Upon a rise in temperature, the force of spring 17 increases until it finally exceeds the force of spring 20 and presses the valve closure member 9 against the valve seat 8. In the now closed position of the valve, the water in the radiator and in the return conduit can cool off because the supply of further hot water is blocked. In this closed position, the convolutions of spring 17 lie apart so that the water makes large area contact with the spring 17.
After the water has cooled off sufficiently, the coil spring 17 will axially contract again so that the valve closure member 9 is lifted off the valve seat 8 under the force of the spring 20 and the flow is freed again until the water temperature in the housing 1 again falls below the lower limiting value.
8y reason Or using the shape memory effect metal for the hellcal spring 17, even a sllght change in temperature of, for example, 5 to 10C will enable the entire strdke of the valve closure member 9 to be executed so that the valve will be very sensitive in responding to temperature changes. The high speed of response results from the low mass of the hellcal spring 17 and hence its low thermal capacity.
Further, the large surface area of spring 17 contributes to a reduction 1~328~8 ln the response delay.
The use of the SME metal for spring 17 has the additional advantage that the distance-temperature characteristic of spring 17 is independ-ent of the static pressure of the water, in contrast with an actuating element having a temperature sensitive expansible material such as steam, a liquid or wax in an expansible container.
The screwsthreaded ring 5 serves as an adjustable counter-bearing for the helical spring 20. By adjusting the ring 5, it ls therefore possible not only to select the pre-stressing of the helical spring 20 but also the spacing between the sealing disc 10 and the valve seat 8 in the open conditlon of the valve so that on the one hand the hysteresisf the valve is reduced and on the other hand it is possible to set different opening and closing temperatures.
In the open condition of the valve, the water flows practically unhind-ered through the screwthreaded ring 5, the annular chamber 21 and partially also through the annular chamber disposed outside the spring 20, through the apertures 13, the interior chamber of the valve closure member 9 and the interior of the helical sprlng 17 without the through-flow being markedly hindered. The internal diameter of the housing 1 can therefore be approximately the same as the external diameter of the helical springs 17 and 20. It is only necessary to maintain a certain amount of play between the external circumference of the helical springs 17 and 20 and the inside of the housing 1 in order to 13~2828 permit movement of springs 17 and 20 and of the valve closure member 9 within the housing 1. With a comparatively large flow section, the valve can therefore nevertheless have a small external diameter so that it can be built into even existing return conduits and convention-al fittings having a small internal diameter.
In the return conduit, the valve serves as an automatic return temper-ature limiting device. In this way one can obtain a low temperature for the return water. This leads to a higher efficiency in boilers which are cooled by the flue gas. Upon starting the heating install-ation, losses are avoided if there has been a preceding drop in the desired temperature, e.g. during-night time. Losses are also avoided if the desired value of the preceding temperature is increased.
Further, lo~ses are avoided as a result of ventilating a heated room, without reducing the preceding temperature.
The use of the elastically resilient seallng disc 10 ensures that the valve will seal tightly and the helical spring 17 need not be subjected to high excess temperatures with a correspondingly high closing force which could result in larger hysteresis.
The example of Figs. 7 and 8 differs from that of Figs. 1 to 6 substan-tially only in that the housing 1a has thinner walls, does not have a screwthread and is provided at the inlet end with a conical flange 22, and the valve ~eat 8 is in the form of an annular disc at a counter-bearing 5a which is fixed with respect to the housing. The shoulder 18 of housing 1a serving as a counter-bearing for the helical spring 17 can be pushed axially inwardly by means of a setting apparatus in order to set the free path between the counter-bearings 5a and 18 for the helical springs 17 and 20 or their pre-stressing and so that the opening and closing temperatures of the valve can be set to the desired values. In this valve there is again a small external diameter as shown in Fig. 8, so that it can be easily inserted in a conventional return conduit and secured with a cap nut.
In the example of Fig~. 9 to 14, the housing 1b is provided on the inlet side with a cylindrical external screwthread 2a and on the outlet side with an internal screwthread 23 and an external hexagon for connecting it into the return conduit. Further, it has a radially pro~ecting nipple 24 which bounds an aperture in the housing 1b and has an internal screwthread 25 into which there i9 screwed a set screw 26 which i9 sealed from the nipple 24 by means of an 0 ring 27 and a conical point 28. The conical point 28 of set screw 26 lies against a complementary conical external surface 29 of a counter-bearing 30 for the temperature sensitive helical spring 17 on the side of the counter-bearing 30 remote from the spring 17. Further, the housing 1b contains a substantially star-s~aped guide 31 with a hub 32 coaxial with the axis of the housing 1b. In the hub 32, the counter-bearing 30 is mounted for axial displacement with a cylindrical extension 33 on the side of the counter-bearing 30 remote from the helical spring 17.
Radially extending webs 34 of the guide 31 connected to the wall of 133282~
the houslng deflne between each other axlal apertures 35 for the throughflow of the water. On its side facing the helical spring 17, the counter-bearing 30 is substantially pot-shaped and is provided in its circumferential wall 36 with radially and axially extending aper-tures 37 which also partially go through the base 38 of counter-bearing 30. One end of the temperature responsive helical spring 17 is supported at the base 38 of counter-bearing 30. The other end of spring 17 is supported at the base 15 of the valve closure member 9a which i9 of the same construction as the valve closure member 9 except that its flange 16 has been omitted and, instead, the internal diameter of the still substantially pot-shaped valve closure member 9a is increased, so that the helical spring 17 finds space within the circum-ferential wall 14. The valve seat 8a is in the form of an edge.
In this example, the water can flow through not only within but also outslde the temperature responsive helical spring 17 when the valve is open. Even with the valve closed practically the entire surface of the temperature responsive helical spring 17 is in contact with the water, so that the response delay or time constant of spring 17 with respect to a change in temperature is still less. Nevertheless, one obtains a comparatively small external diameter for the valve with a sufficiently free flow section. Ad~ustment of the counter-bearing 30 is possible with the aid of the set screw 26 and thus an ad~usting possibility additional to that achieved by the screwthreaded ring 5, ad~ustment of the set screw 26 being possible from the outside even when the valve is built into the return conduit. Further, the set J
screw 26 can be screwed in so deeply that the valve ls tightly closed and the thermostatic function is eliminated.
The construction of valve seat 8a in the form of an edge gives a larger surface pres~ure and thus a better sealing effect with the same pressing force by the valve closure member 9a as in the preceding examples.
Insofar that the example of Figs. 15 and 16 uses the same components as in the preceding examples, the same reference numerals are used.
The main difference i9 that the valve is one with an angled housing 1c and, in addition to the screwthreaded ring 5, a securing ring 39 is provided in the housing 1c. Further, the apertures 13a do not extend over the entire length of the circumferential wall 14 of the valve cloqure member 9.
The example of Figs. 17 and 18 differs from that of Figs. 15 and 16 only in that the screwthreaded ring 5 has the same valve seat 8 as the Fig. 1 example and the securing ring 39 is omitted.
The example of Fig~. 19 and 20 likewise has an angled housing 1d.
Whereas the counter-bearing 5b for the helical spring 20 i~ fixed with respect to the housing, the counter-bearing 30a for the helical spring 17 is also in this case ad~ustable. For this purpose, the counter-bearing 30a has an external screwthread 40 with which it engages in an internal screwthread 41 in a sub~tantially pot-shape cylindrical extension 42 of housing ld that is axially in line with the helical springs. The counter-bearing 30a is sealed against the housing exten-sion 42 with the aid of two 0 rings 43. Between the 0 rings 43, the counter-bearing 30a has an externally extending row of depressions 44 of which the intermediate walls form a gear ring. These depression~
44 are accessible to a setting element (not shown), for example a screwdriver, by way of an elongate aperture 24b of housing 1d so as to turn the counter-bearing 30a and thereby ad~ust it in the axial direct-ion.
The Figs. 21 to 23 example substantially corresponds to that of Figs.
19 and 20 except that here the housing 1e is provided with the nipple 24 and as a setting element there is a worm 26a of which the screw-thread 45 engages in tooth gaps 44a of a gear ring surrounding the counter-bearing 30b. The worm 26a is provided with a collar 46 abutt-ing a bushing 47 which i8 screwed into the screwthread 25 of nipple 24 and has an external screwthread for securing the position of the worm 26a.
By turning the worm 26a, the counter-bearing 30b is also turned and ad~usted in its axial direction by reason of its screwthread 40 engag-ing in the screwthread 41.
The example of Figs. 24 and 25 again comprises an angled housing 1f and, as far as the inlet side is concerned, substantially corresponds to the examplè of Fig. 19 and, as far as ad~u~tment of the counter-bearing 30 is concerned, corresponds substantially to the example of 13328~8 Figs. 9 to 14 except that the nipple 24 extends obliquely to the circumferential wall of the housing 1f and perpendicular to the conical external surface 29 of the counter-bearing 30. The setscrew 26b does not have a conical tip but has a flat at its end for lying against the exterior surface 29 of the counter-bearing 30. The counter-bearing 30 is displacably mounted with an extension 33 in a guide bore 32a. In thi~ embodiment, the counter-bearing 30 of the spring 17 is again ad~ustable in the axial direction of spring 17 by turning the setscrew 26b.
The example of Figs. 26 to 28 substantially corresponds to that of Figs. 24 and 25 except that the setting element 26c has an eccentric 48 of which the cross-section ls illustrated in Fig. 28 and which lies against the side of the counter-bearing 30c remote from the valve closure member 9a, the counter-bearing being displaceablein the housing 1g. The setting element 26c is on the one hand rotatably mounted in the bushing 4~ and on the other hand rotatably mounted by an axial extension pin 49 in a bore of the housing 1g. By turning the setting element 26c, the counter-bearing 30c is likewise ad~usted in the present example.
The example of Figs. 29 and 30 substantially corresponds to that of Figs. 24 and 25 except that the nipple 24 is again perpendicular to the inlet section of the housing 1h and the setscrew 26 is provided with a conical tip 28 as in the example of Fig. 9. The operation is therefore the same as in the example of Fig. 19.
In the example of Figs. 31 and 32, which likewise comprises an angled housing 1i, the inlet portion likewise corresponds to that of Fig. 19.
On the other hand, the cylindrical axial extension 33 of the counter-bearing 30d is sealingly guided with the aid of an O ring 50 in a guide bore 32b which is coaxial to the helical springs 17 and 20, the extension 33 eng~g~ng in -an end depression 51 of the set screw 26d in the houslng extension or in the nipple 24 and the housing extension 24 being coaxial to the helical springs 17, 20. Further, by means of a shank 52 reduced relatively to its screwthreaded section, the set screw 26d passes through a coaxial bore 53 in a cap nut 54 which is screwed on to the nipple 24 and serves to secure the set screw 26d axially. In this example, ad~ustment of the counter-bearing 30d in the housing 1i coaxial to its inlet section or the helical springs 17, 20 is brought about by turning the set screw 26d.
In the example of Figs. 33 to 35, the temperature responsive actuating element 17a is a thin cylindrical wire. The material of the wire 17a is preferably an SME metal of a nickle-titanium alloy activated so that the wire 17a contracts on heating and expands on cooling. This alloy can, however, also be designed so that it expands on heating and contracts on cooling. Compared with a Cu-Zn-Al alloy, it has the advantage of a longer change in length depending on the temperature.
A very thln wire will therefore suffice. The wire 17a has its one end section received in an axially throughgoing bore 55 of the valve closure member 9b and its other end section is secured to a sleeve 56 which is coaxial with the housing 1~, projects axially from the housing 1~ and is secured with its inner end in a coaxial bore 57 of the 133282~
housing 1~ so that the sleeve 56 forms a counter-bearing fixed with -respect to the housing for the wire 17a clamped therein.
The counter-bearing 5b for the helical spring 20 at the same time brings about centering of the valve closure member 9b while maintaining its radial play for the axial displacement of the valve closure member 9b.
The end section of wire 17a received in the bore 55 of the closure member 9b is tightly clamped in a ~oint member 58 with a conical sealing face. The ~oint member 58 is sealingly held from the outlet side of the valve against an edge 59 of a step in the bore under the pressure of the temperature insensitive helical spring 20 which act~
by way of the sealing discs 10 on the annular shoulder 21 of a radially outwardly pro~ecting flange 68 of the valve closure member 9b, whilst the valve closure member 9b is lifted off the valve seat 8a. With the valve 8a, 9b closed, the ~oint member 58 lies against the edge 59 under the tensile force of the wire 17a which contracts on heating and expands on cooling, so that the ~oint member 58 lies tightly against the edge 59 under all operating conditions and prevents the passage of fluid but at the same time cardanically supports the valve closure member 9b. The cardanic bearing ensures that the valve closure member 9b will not assume an oblique position relatively to the valve seat 8a but will always lie against the entire valve seat 8a when it is closed.
The housing 1~ is provided with axial passages 60 which are radially o inwardly open towards the bore 57 and leave a passage for the warm water externally of the coil spring 20. With a radial spacing from the valve seat 8a, the coil spring 20 lies on the inside of the valve seat at the sealing disc 10.
With the valve 8a, 9b open, the warm water can flow on the one hand through radial bores 61 in the sleeve 56, the bore 55, radial bores 62 of the valve closure member 9b and the intermediate spaces between the convolutions of the hellcal spring 20 and on the other hand through the passages 60.
When the wire 17a cools off and expands, the valve 8a, 9b is opened under the pressure of spring 20.
The helical ~pring 20 i9 SO dimensioned that its convolutions will, even with the valve 8a, 9b closed, have a sufficient spacing for the throughflow of the warm water.
In this example, the warm water can again flow through the housing 1~
practically unhindered when the valve 8a, 9b is open, it again being possible to have a very small external diameter for the housing 1~
because the temperature sensitive actuating element 17a likewise has a very small diameter and, by reason of its considerable length, never-theless ensures a long actuating strdke over a very small temperature range.
In the example of Figs. 36 and 37, the actuating element 17b is an elongate pin of SME metal which expands on heating and contracts on cooling and which i8 considerably longer than the housing lk of the valve. Here, again, the valve closure member 9c is hollow cylindrical, passes through the valve seat 8a and pro~ects from the housing lk to a large extent. The temperature sensitive pin 17b pro~ects with its one end section into the bore 55 of the valve closure member 9c and with its other end section into a hollow cylindrical base extension 63 of the otherwise substantially pot-shaped housing lk of which the base is provided with axial apertures 64 further radially beyond the extension 63.
The counter-bearing 5c for the temperature insensitive helical spring 20 is in the form of a cap nut which is screwed into the internal screwthread 7 of the housing lk and is provided with lateral apertures 65 for the passage of the hot water.
The pin 17b is supported on the one hand at the base of the extension 63 and on the ~ther hand at the set screw 26 which is screwed into that end of the valve closure member 9c that pro~ects from the housing lk, the set screw abutting the end of the pin 17b. In this example, the valve stroke or pre-stressing of the helical spring 20 is likewise adJustable by turning the set screw 26 and, if desired, by turning the counter-bearing 5c.
The example of Figs. 38 and 39 differs from that of Figs. 36 and 37 only in that the set screw 26 i9 omitted and the valve closure member 9d is instead closed at the end pro~ecting from the housing 9k.
Claims (9)
1. A temperature-responsive valve comprising a housing through which, in use, fluid passes and in which there are arranged, substantially co-axially with each other, a first helical spring which, in use, expands and contracts depending on the temperature of fluid passing through the valve, acts against the housing and is arranged to bring about the closing and opening of the valve, and a second, substantially temperature-insensi-tive, helical spring for biasing the first helical spring, wherein a valve seat and a valve closure member are provided within the housing, the temperature-respon-sive first helical spring has one end acting against the housing and the other end acting against that side of the valve closure member remote from the valve seat, the second helical spring has one end acting against the housing at a location radially outwards of the valve closure member, and the other end acting against that side of the valve closure member facing the valve seat and acts against the force of the first helical spring tending to close the valve, and at least one aperture is provided in the valve closure member establishing communication between the interior of the first helical spring and an annular chamber, within the second helical spring, located radially outwards of the valve seat.
2. A valve as claimed in claim 1, wherein the first helical spring is a shape memory effect spring.
3. A valve as claimed in claim 1, wherein the valve closure member comprises a resilient sealing disk on that side of the valve closure member facing the valve seat.
4. A valve as claimed in any one of claims 1 to 3, wherein the valve closure member is substantially cup-shaped and has apertures passing radially through the circumferential wall of the cup-shaped valve closure member.
5. A valve as claimed in claim 4, wherein the apertures extend over substantially the entire axial length of the valve closure member and pass through a part, lying to the side of the valve seat, of a base of the valve closure member.
6. A valve as claimed in any one of claims 1 to 3, wherein the end of the first and/or second helical spring remote from the valve closure member acts against an axially-adjustable counter-bearing.
7. A valve as claimed in claim 6, wherein the end of the first helical spring acts against an axially-adjustable counter-bearing, and an aperture is provided in the housing through which a setting tool may be inserted for the purpose of adjusting the counter-bearing of the first helical spring.
8. A valve as claimed in claim 6, wherein the end of the second helical spring acts against an axially-adjustable counter-bearing, and the valve seat forms part of the counter-bearing of the second helical spring.
9. A valve as claimed in claim 7, wherein the end of the second helical spring acts against an axially-adjustable counter-bearing, and the valve seat forms part of the counter-bearing of the second helical spring.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3814519.7 | 1988-04-29 | ||
| DE19883814519 DE3814519A1 (en) | 1988-04-29 | 1988-04-29 | TEMPERATURE-DEPENDENT VALVE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1332828C true CA1332828C (en) | 1994-11-01 |
Family
ID=6353191
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 596338 Expired - Fee Related CA1332828C (en) | 1988-04-29 | 1989-04-11 | Temperature responsive valve |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPH01320388A (en) |
| CA (1) | CA1332828C (en) |
| DE (1) | DE3814519A1 (en) |
| DK (1) | DK165018C (en) |
| FR (1) | FR2630807B1 (en) |
| GB (1) | GB2217816B (en) |
Families Citing this family (28)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5123593A (en) * | 1990-01-23 | 1992-06-23 | Rundle Gregory E | Manual override heat sensitive valve |
| DE4016748A1 (en) * | 1990-05-25 | 1991-12-19 | Teves Gmbh Alfred | Pressure controller for vehicular antilock and antislip braking - includes construction in line from master cylinder to wheel brake cylinder with pressure limited by valve |
| DE4031232C2 (en) * | 1990-10-04 | 2000-02-17 | Bosch Gmbh Robert | Fuel supply device for internal combustion engines |
| JP2571163B2 (en) * | 1991-07-10 | 1997-01-16 | リンナイ株式会社 | Thermal response valve |
| EP0624836A4 (en) * | 1992-11-25 | 1995-07-26 | Toto Ltd | Hot water/cold water mixing apparatus and hot water/cold water mixing method. |
| AT398236B (en) * | 1992-12-22 | 1994-10-25 | Ideal Standard | MIXER BATTERY FOR SANITARY PURPOSES |
| US5261597A (en) * | 1993-03-04 | 1993-11-16 | Maier Perlman | Temperature responsive 3-way line valve with shape memory alloy actuator |
| JP3237300B2 (en) * | 1993-05-19 | 2001-12-10 | アイシン精機株式会社 | Valve device for preventing clutch shock torque |
| DE4322731A1 (en) * | 1993-07-08 | 1995-01-12 | Leybold Ag | Valve for regulating fluid flows with an actuator made of electrically heatable, shape-remembering material |
| GB2311119A (en) * | 1996-03-11 | 1997-09-17 | Sunderland Holdings Ltd | In-line temperature activated valve |
| DE19934445A1 (en) * | 1999-07-26 | 2001-02-01 | Oliver Weis | Valve control has helical spring with ends, coils and interior, two fluid chambers, thrust bearing, and passages |
| DE10118338A1 (en) * | 2001-04-12 | 2002-11-07 | Bosch Gmbh Robert | Hot water radiator return feed has thermostat valve with negative temperature feed profile preventing return of hot water |
| DE10251167B4 (en) | 2002-10-31 | 2004-10-14 | Danfoss A/S | axial valve |
| CN100359232C (en) * | 2004-09-06 | 2008-01-02 | 上海华诚通信器材有限公司 | Sequence valve with temp. memory |
| FR2913374B1 (en) * | 2007-03-08 | 2009-04-10 | Itw Bailly Comte Soc Par Actio | COOLING SYSTEM OF A MOTOR VEHICLE, DEGASSING TANK AND CORRESPONDING MOTOR VEHICLE |
| DE102010009173A1 (en) * | 2010-02-24 | 2011-08-25 | Otto Egelhof GmbH & Co. KG, 70736 | Valve for controlling a flow channel |
| DE102011102881A1 (en) * | 2010-06-17 | 2011-12-22 | Schaeffler Technologies Gmbh & Co. Kg | Hydraulic element |
| US8708243B2 (en) | 2010-10-19 | 2014-04-29 | Hs Marston Aerospace Ltd. | Thermal valve |
| DE102011075123B4 (en) * | 2011-05-03 | 2017-05-11 | BSH Hausgeräte GmbH | Flow restrictor, flow restrictor, flow restrictor, radiator and instantaneous water heater |
| DE202011101087U1 (en) | 2011-05-25 | 2011-07-14 | Wolfgang Buttner | Thermostat for radiator valves with 2 functions |
| CN103133756A (en) * | 2013-02-01 | 2013-06-05 | 浙江华地电子有限公司 | Water flow sensor of gas water heater and automatic outlet water quantity regulating device of water flow sensor |
| DE102013004908B3 (en) | 2013-03-22 | 2014-02-06 | Ksb Aktiengesellschaft | Valve and pump arrangement with valve |
| ITMI20130894A1 (en) * | 2013-05-31 | 2014-12-01 | Fluid O Tech Srl | ANTI-VACUUM VALVE FOR HYDRAULIC CIRCUITS CONTAINING A BIPHASIC FLUID |
| CN104055351B (en) * | 2014-07-01 | 2019-02-15 | 张铁志 | Hot-water warming mattress without pump circulation heating device |
| DE102017003956A1 (en) * | 2017-04-22 | 2018-10-25 | Thomas Magnete Gmbh | Electromagnetically driven reciprocating pump |
| DE102017220145B4 (en) * | 2017-11-13 | 2019-06-13 | Festo Ag & Co. Kg | valve means |
| DE102018206276A1 (en) * | 2018-04-24 | 2019-10-24 | Zf Friedrichshafen Ag | Thermostatic valve |
| CN112879583B (en) * | 2021-01-11 | 2022-02-11 | 宁波方太厨具有限公司 | Adjustable flow stabilizing valve |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB798427A (en) * | 1956-04-23 | 1958-07-23 | Ludwig Domnick | An apparatus for the discharge of condensation water |
| GB902579A (en) * | 1959-06-24 | 1962-08-01 | E M B Co Ltd | Thermally regulated liquid control valve |
| DE1229805B (en) * | 1964-05-09 | 1966-12-01 | Gerdts Gustav F Kg | Thermally controlled valve |
| FR1602959A (en) * | 1967-08-10 | 1971-03-01 | Lift-type thermostatic valve | |
| US4068820A (en) * | 1974-08-26 | 1978-01-17 | Texas Instruments Incorporated | Valve |
| GB1539637A (en) * | 1977-12-15 | 1979-01-31 | Standard Telephones Cables Ltd | Over temperature cut out |
| EP0010350B1 (en) * | 1978-09-22 | 1982-01-06 | Western Thomson Controls Ltd | Thermostatically controlled valve, method of making same and apparatus for performing the method |
| JPS5716191A (en) * | 1980-07-04 | 1982-01-27 | Kawasaki Steel Corp | Electrolytic bath for acidic manganese plating |
| GB2107829A (en) * | 1981-06-09 | 1983-05-05 | Dudley Vernon Steynor | Thermostatic valves, and solar water heating systems incorporating the same |
| JPS5824669A (en) * | 1981-07-31 | 1983-02-14 | Sharp Corp | Hot and cold water mixing faucet |
| DE3339437A1 (en) * | 1983-10-29 | 1985-05-15 | Krytem GmbH, 4156 Willich | Temperature-controlled shut-off apparatus |
| JPS60101378A (en) * | 1983-11-09 | 1985-06-05 | Kato Hatsujo Kaisha Ltd | Temperature responding valve |
| JPS60245887A (en) * | 1984-05-18 | 1985-12-05 | Aisan Ind Co Ltd | Safety device in combination faucet |
| JPS60263790A (en) * | 1984-06-12 | 1985-12-27 | Matsushita Refrig Co | Temperature-sensitive operation valve |
| JPS61184285A (en) * | 1985-02-08 | 1986-08-16 | Sumitomo Electric Ind Ltd | Anti-freezing valve |
| JPS61241582A (en) * | 1985-04-17 | 1986-10-27 | Sanyo Electric Co Ltd | Valve apparatus |
-
1988
- 1988-04-29 DE DE19883814519 patent/DE3814519A1/en active Granted
-
1989
- 1989-03-22 DK DK140889A patent/DK165018C/en not_active IP Right Cessation
- 1989-04-11 CA CA 596338 patent/CA1332828C/en not_active Expired - Fee Related
- 1989-04-28 FR FR8905726A patent/FR2630807B1/en not_active Expired - Fee Related
- 1989-04-28 GB GB8909770A patent/GB2217816B/en not_active Expired - Lifetime
- 1989-05-01 JP JP11275689A patent/JPH01320388A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01320388A (en) | 1989-12-26 |
| DE3814519A1 (en) | 1989-11-09 |
| DK165018B (en) | 1992-09-28 |
| GB2217816A (en) | 1989-11-01 |
| DK140889A (en) | 1989-10-30 |
| DE3814519C2 (en) | 1992-06-11 |
| GB8909770D0 (en) | 1989-06-14 |
| FR2630807B1 (en) | 1993-12-10 |
| GB2217816B (en) | 1992-05-27 |
| FR2630807A1 (en) | 1989-11-03 |
| DK165018C (en) | 1993-02-08 |
| DK140889D0 (en) | 1989-03-22 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |