EP0962951A2 - Thermal switch, in particular adjustable temperature controller - Google Patents

Abstract

A temperature regulator working with a hydraulic expansion socket (5) has a lever device (30) for transmitting force between the expansion socket and the switching spring (21) of a snap switch (20). A buffer is integrated into this for overload protection for the switching spring, which is elastically flexible above a limit force assigned to the actuating force of the switching spring in the switching point and is essentially rigid below the limit force. The unit consisting of a buffer and lever device is formed by a switching rocker (31) in the form of a bent sheet metal part, which has an L-shaped pivoting lever section (40) with which a bow spring (41) that is preloaded in the opening direction and opens to a limit is formed in one piece.

Description

The invention relates to a temperature switch, in particular an adjustable temperature controller, according to the generic term of claim 1.

A generic temperature switch has a temperature sensitive Expansion element that has a power transmission acts on a switch spring of a snap switch. There is also an overload protection for the switching spring intended. The overload protection has at least one Buffer with the force transmission between the expansion element and switching spring cooperates, especially in the Power flow of the power transmission is installed. The buffer is above one of the actuating force of the switch spring in Limit force assigned to the switching point can be changed or compliant while he is below the limit temperature in can be essentially unyielding or rigid.

Such a temperature switch is from DE 196 27 969 known. He has one as a force translation or force translator Power transmission element serving rocker arm, the from an expansion box of a thermo-hydraulic expansion system via an intermediate buffer element is pressed and which acts on the snap switch. The Buffer element consists of a closed box that is made of two pot-shaped, overlapping halves, between which a compression spring is biased. The buffer element transmits the switching force of the expansion socket in the Force range in which the snap spring actuation takes place completely rigid while going beyond one overload becomes compliant and telescopes. A metallic can half of the three-part Buffer element is firmly attached to the expansion socket. When the temperature controller is installed, the spring is then inserted to generate a preload using the other can part and the can parts are connected to each other by bending claws. At the further assembly will then be on the expansion element attached buffer element placed on the operating lever. This system works fine, but is in the Manufacturing, especially during assembly, is quite complex.

The invention has for its object a temperature switch of the type mentioned at the outset, which is inexpensive is manufacturable and easy to assemble.

This problem is solved by using a temperature switch the features of claim 1.

According to the invention, the buffer and the power transmission form a designable as a buffered power transmission unit Unit, i.e. a unit that contains both the Power transmission functions between expansion element and switching spring, as well as the function of the buffer, which below its limit force like a rigid element of Power transmission works, but one above its limit force brings certain flexibility into the power transmission. The Invention enables complete, essentially through the load-dependent buffered or damped power transmission unit and the snap mechanism formed as snap mechanism an assembly, for example on a base of the Temperature switch regardless of the expansion system pre-assemble, for further assembly the expansion element comprehensive assembly put on and adjusted if necessary without attachment between the expansion element and snap mechanism must be provided. Through the Integration of the overpressure protection device implemented by the buffer in the power transmission it becomes possible commercially available, standardized for such temperature switches Use expansion elements as the whole Devices for overload protection in the snap mechanism, especially in the force transmission actuating the switching spring are integrated. In addition, with a buffered Power transmission unit the relative location of the buffer and Power transmission before assembling the temperature switch fixed so that there are geometry-related inaccuracies minimize.

In preferred embodiments, the power transmission has a lever device with at least one lever on the preferably one-sided in the manner of a cutting edge bearing is supported and / or has a lever arm that on the Switching spring, preferably with point contact, acts. A lever is a simple power transmission element whose power transmission over the effective Lever lengths can be selected. The power transmission can be 1: 1 take place, but preferably strengthening or reducing force Act. A translation lever can be used to increase the Snap spring sensitivity can be used. A special one simple embodiment is with a substantially L-shaped Lever given either on a switch spring carrier hung and supported or in a recess of the Switch spring carrier or in a separate recess for example, the switch base can be performed.

One especially for overpressure protection of the switch spring effective embodiment is characterized in that a Stop is provided on which the lever, in particular the lever arm acting on the switch spring after overcoming the switching point for the switching spring preferably supports directly. The support can move the Release the lever after the desired switching process has expired is and far before the elastic range of the spring is exceeded and this if necessary by overpressing and thus associated plastic deformation are permanently damaged could. The stop is preferably by a projection a shift spring support, in particular through the shift tongue abutment, educated. However, it is also possible to Stop by a projection or section of the switch base to form and / or if necessary at the by the stop path-limited lever arm or another point on the lever provide a separate approach to support. When the lever has reached its stop position and itself the expansion element continues to expand, so by Power transmission buffers also provide overpressure protection for the Expansion element and the rest of the mechanics of the temperature switch created. A direct stop for the lever can also in generic types other than those designed according to the invention Temperature switches, for example those according to the DE 196 27 969 may be provided.

An embodiment with a particularly small number effective components in power transmission, the corresponding is not very susceptible to faults, characterized in that the Buffer at least one preloaded, in the spring direction, especially in the direction of expansion, self-captivating or includes self-limiting spring element. To limit the Travel is therefore not a separate component from the spring required. The spring element is preferably in shape a biased in the opening direction of your legs, preferably U-shaped bow spring, the opening is limited by a spring stop. Below one sufficient to compress the legs Such a spring element is essentially a load rigid or dimensionally stable, while above a limit force let the thighs squeeze. For self-bondage of the Spring element or to implement the in the spring element Integrated path limitation can have at least one on one Spring section, e.g. hook attached to one leg be provided, in particular the shape of a bending tab may have. This can be on another spring section or grip behind the provided projection. The The contact surface at the stop is preferably small, for example linear or punctiform, whereby the Spring length or width in the stroke-limited state very much exactly definable and also with multiple overloading and subsequent relief of the spring element reproducible is.

A particularly easy to assemble and reliable Execution is given when the load-dependent buffered or damped power transmission unit, which is also used as a buffer lever assembly can be called a single, is a one-piece component, in particular a spring plate bent part. This can act as both lever sections also have sections acting as buffers, especially one Section that forms a self-captivating bow spring. Of the Lever or lever section can have an L-shape and for example two, forming a cutting edge bearing, in lateral Have spaced support legs. between the support legs can, preferably symmetrically, a self-limiting spring element forming the buffer lie, for example one leg of a bow spring with the support leg sections adjacent on both sides first forms a three-pronged fork arrangement and the appropriate tines to complete a steamed Shift paddle bent in opposite directions accordingly become. Laterally protruding projections of the fork part can then by bent retaining tabs on the sides of the behind the other leg of the U-shaped bow spring and thereby bring about the self-restraint of the bow spring.

Permanently reliable temperature switches can in particular then be created when the expansion unit an expansion box of a thermo-hydraulic expansion system includes. Thanks to the invention it is possible that the Expansion unit, especially the one also called Diastat Expansion box, when the temperature switch is assembled in unconnected system contact with the buffer lever unit or one resilient on a housing of the switch attached insulating piece stands. The touch contact can can be made during the assembly of the switch without separate connection means, such as screws or solder joints, must be provided. Such is correspondingly easy Temperature switch can also be removed in order to replace defective parts.

Electrical insulation between possibly live Share the power transmission and the expansion element advantageous to achieve in that the buffer lever assembly via a preferably pressure-rigid insulating piece made of electrically insulating, in particular ceramic material, supported on the expansion unit. The insulating piece can be detachably or permanently attached to the assembly and can be installed together with it. The insulating piece can also be movable, in particular resilient, for example via a bow spring, attached to the housing and thus Be part of the housing assembly.

A particularly flat design can be achieved if instead of the also possible expansion box with two bowl-shaped sheet metal membranes and central connection nipple a flat membrane is used for a capillary tube at the the capillary tube in the area of the peripheral edge of the Leads essentially radially directly into the interior of the can, without the need for a separate connection nipple.

Alternative to embodiments in which buffers and power transmission or lever device a single one-piece Form part, it is also possible that the buffer with a the power transmission firmly connectable or connected is a separate buffer element, which before assembly of the temperature switch with the power transmission, in particular the rocker arm, to form a buffered power transmission unit preferably insoluble, for example by a rivet connection or welding. The preferably variable-length buffer element can be used as Pressure element be formed, the pressure load below the intended limit force is essentially dimensionally stable and reversible above the limit force, for example is telescopic, compressible. For example the three-part buffer elements known from DE 196 27 969 with two, enclosing a prestressed compression spring, interlocking can parts are used, a can part can be attached to the rocker switch.

These and other features go beyond the claims also from the description and the drawings, wherein the individual features individually or separately several in the form of sub-combinations in one embodiment of the invention and in other fields be and can represent advantageous designs. The Subdivide the application into individual sections as well Subheadings limit those made under them Statements are not generally applicable.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1

einen Längsschnitt durch eine Ausführungsform eines erfindungsgemäßen Temperaturreglers,

Fig. 2(a)

eine Seitenansicht einer als einstückiges Blech-Biegeteil ausgebildeten Puffer-Hebel-Einheit,

Fig. 2(b)

eine vergrößerte Detailansicht des eingekreisten Bereichs in Fig. 2(a),

Fig. 3

eine Vorderansicht der Puffer-Hebel-Einheit von Fig. 2,

Fig. 4

eine Draufsicht auf die Puffer-Hebel-Einheit von Fig. 2 im Schnitt entlang Linie IV-IV in Fig. 2(a),

Fig. 5

eine andere Ausführungsform eines Temperaturreglers mit einer Flachmembran-Ausdehnungsdose,

Fig. 6

eine weitere Ausführungsform eines Temperaturreglers mit einer anderen, einstückigen Puffer-Hebel-Einheit und einem dem Gehäuse zugeordneten Isolierstück im Längsschnitt und

Fig. 7

einen Querschnitt durch die Ausführungsform nach Fig. 7.

Embodiments of the invention are shown in the drawings and are explained in more detail below. The drawings show:

Fig. 1

2 shows a longitudinal section through an embodiment of a temperature controller according to the invention,

Fig. 2 (a)

2 shows a side view of a buffer-lever unit designed as a one-piece sheet-metal bent part,

Fig. 2 (b)

3 shows an enlarged detailed view of the encircled area in FIG. 2 (a),

Fig. 3

3 shows a front view of the buffer lever unit from FIG. 2,

Fig. 4

2 shows a plan view of the buffer lever unit of FIG. 2 in section along line IV-IV in FIG. 2 (a),

Fig. 5

another embodiment of a temperature controller with a flat membrane expansion socket,

Fig. 6

a further embodiment of a temperature controller with a different, one-piece buffer-lever unit and an insulating piece assigned to the housing in longitudinal section and

Fig. 7

7 shows a cross section through the embodiment according to FIG. 7.

The longitudinal section in Fig. 1 shows the switching components of a first embodiment of a temperature controller 1, the with a thermohydraulic expansion system 2 cooperates. The expansion system includes a schematically indicated one Temperature sensor 3 in the form of an expansion liquid filled tube, which via a capillary tube 4 with an expansion element in the form of an expansion box 5 connected is. The expansion box consists of two bowl-shaped, corrugated sheet membranes attached to their in the figure edges bent upwards by welding or soldering are connected to each other in a pressure-tight manner. About one in the Shell of the expansion socket in a centrally arranged connection nipple 6 is the capillary tube 4 with the inside of the between the corrugated sheet metal shells formed cavity. On the top of the nipple 6 is integral with the nipple Retaining pin 7 provided in a hollow setting shaft 8 is. This has an external thread 9 with an internal thread cooperates, which is provided in a sleeve 10 is that in the top 12 of a box-shaped Metal housing 13 is integrally formed with this. The Adjustment shaft 8 is flattened on one side by an adjustment button non-rotatably. There is an adjusting screw in it 14 provided on the retaining bolt 7 to its vertical Acts adjustment.

The housing 13 is made of sheet metal and has the shape of a rectangular, partly openwork box whose top 12 mounting brackets 15 for installing the Temperature controller are formed. The bottom of the case will of a base part or base 16 made of temperature-resistant, dimensionally stable and electrically insulating material, for example Steatite or other ceramic material, educated. On the base 16, the housing 13 is by twisting tabs 17 set.

The plate-shaped base part 16 carries a snap switch 20. This has a switching spring 21 on a switching spring carrier 22 is attached. The switch spring carrier 22 is a relatively small, solid sheet metal part, which is a switch tongue abutment 23 in the form of an upward bend having. There is a shift tongue 24 on the shift tongue abutment supported by an approximately U-shaped incision by the remaining switching spring is disconnected. Because of their deflection and the preload that it gives the switching spring can with their remote ends by rivets on the switch spring support fixed switching spring with its front, the switching contact 25 load-bearing end at its switching point between two stable Snap switch positions. In the one shown in Fig. 1 The switch-off position is at the front end of the switch spring one formed from the base part and forming a counter bearing Projection 26 on. The switch is in the on position Contact 25 on a counter contact 27, which is on a Mating contact bridge 28 is located under one by the spring provided contact pressure.

The snap switch carrier 22 and the mating contact bridge 28 create fastening lugs by U-shaped design on the one hand as twisting tabs 29 and on the other hand as well flat tabs fixed by twisting 19 are formed, via which the electrical connection the underside of the plate-shaped base part.

The snap switch 20 is over with the expansion element 5 a lever device 30 which acts as a power transmission mechanically coupled in such a way that a Expansion of the expansion box 5 over a predeterminable vertical Dimension to an opening of the contact 25, 27th leads. The lever device 30 comprises a buffered or damped rocker switch 31, the structure of which is related Figures 2 to 4 is explained in more detail. Your is a ceramic Insulated button 32 assigned to the top of the rocker switch is attached and is spherical with its upward curved top 33 in the middle of the large flat Underside 34 on the underside of the expansion socket 5 attached metal disc 35 on a small punctiform Supports the contact point. The rigid and electric insulating material of the on a vertically protruding fastening tab 36 of the rocker switch 31 attached ceramic Knob 32 ensures a rigid transmission of the Vertical movement of the bottom of the can onto the rocker switch 31 and creates the necessary electrical insulation between live parts of the snap mechanism 20, 30 and Expansion unit 5. The upward curved edges of the Expansion boxes also promote adequate compliance electrical distances between the snap mechanism and the expansion system. That through the flat underside of the metal disc 35 large, flat contact surface provided for the curved top of the insulating piece 32 ensures that the pressure ratios and thus the switching accuracy of the Regulator essentially independent of small position tolerances the expansion unit.

The switching rocker, designed as a one-piece spring steel bent part 31 combines several functions within the Power transmission and overpressure protection, it includes one essentially L-shaped, as a transmission transmission lever acting lever section 40 and one piece with this trained, acting as a buffer U-shaped curved Bow spring 41, the legs 42, 43 in the opening direction the bow spring are biased and the stop is limited up to a predetermined maximum vertical dimension can open. So it is a one-piece rocker switch with integrated overload damper.

The lever or lever section 40 has to create clearer Pressure ratios with a central, bead-shaped Expression 45 provided lever arm 46 with which he punctiform on an actuation point 47 on a cross extending bead of the switching spring acts. On the opposite End of the lever, which is wider than long, are with large lateral distance from each other two at right angles provided below bent support legs 48, 49, the form lower ends of the cutting edge bearing 50 by being on the Surface of the base part 16 are supported. As in Fig. 3 can be seen, is by a curved lower edge of the Support legs 48, 49 ensure that clear support conditions given are.

The two support legs protrude from both sides a recess in the side edge of the switch spring support 22 into it so that the support legs are guided in it. Protruding Lugs 51 on the inside of the support legs 48, 49 are barb-like and provide after the Lever 40 pressed under pressure from above into the recesses is for a safeguard against lifting the lever.

Below the S-shaped front end the lever arm 46 lies with the rocker arm 31 installed (FIG. 1) the tongue abutment 23, which has a vertical stop for the lever arm 46 forms. Lever shape and stop height are matched to each other so that the switch spring acting lever arm 46 is supported directly on the stop 23, after the switching point for the switching spring is overcome and thus the contact, as shown in Fig. 1, opened is, however, before the switch spring is over its elastic Overpressed area and / or even on the switch spring carrier 22 or the base part 16 is pressed on. Through the Limitation of the lever movement is an absolute limit effective overpressure protection created for the switching spring. Such overpressure protection can also be used for other than Temperature switches designed according to the invention, for example those according to DE 196 27 969 may be provided.

The rocker switch 41 is not over its entire load range essentially rigid, conventional lever, but is able to be below a predefinable one Limit force essentially rigid or dimensionally stable be resilient or resilient above the limit force to be a certain decoupling of the through the Expansion box 5 caused force from the lever arm 46 and / or from the switch spring. This buffer function will created by the stop spring 41 which opens to a limited extent, which is a self-captivating or self-limiting spring element forms. The bow spring 41 sits symmetrically to create Pressure conditions symmetrical between the support legs 48, 49. The by a transition into the expression 45, wide reinforcement bead 52 stabilized against bending Lower leg 42 is a flat, one-piece extension of the lever arm 46. The lower leg 42 goes with one U-shaped bend 53 in when the spring is fully open (Figures 1 to 3) running parallel to the lower leg, also stabilized by an indented bead 54 Thigh 43 over, from the middle of the fastening tab 36 is bent up.

In the area of the free end of the thigh 43 are in Area below the tab 36 laterally U-shaped bending tabs 55, 56 formed in the shown, perpendicular to bent at the bottom, rectangular, lateral projections 57, 58 reach behind the lever arm 46. As in Fig. 2 (b) too recognize, is the one behind the respective projection 57 Section of the bending tab 55 is convexly curved toward the projection, so that the bending tab 55 is limited at the stop fully open spring only on a small area at a point or linear contact point 59 at the bottom of the Projection 57 supports. Thanks to the precise support an exact vertical height (perpendicular to the lever arm 46) of the Shift paddle reproducibly given in this area.

The bow spring 41 has one in the opening direction of its legs Preload that is certainly greater than the limit force, those in the area of the tab 36 or the projections 57, 58 essentially perpendicular to the leg longitudinal direction attacks when the actuating force of the switching spring on their Switching point is reached. This interpretation of the spring strength causes the bow spring 41 under pressure from the Expansion box 5 at least as long as a rigid power transmission element acts until the switching point of the switching spring overcome and the contact 25, 27 is open. About that additional forces on the bow spring legs can in contrast cause a compression of the legs, so that in Force flow between expansion element 5 and switch spring one reversible compliance against overpressure given is.

The assembly of a temperature controller according to the invention is particularly simple, since for snapping the snap mechanism 20, 30 on the base part 16 only simple plugging and bending processes must be made and the connection of the Snap mechanism with the expansion unit 5 only through simple system contact between the large flat Bottom 34 of the metal disc 35 and the dome-shaped Top 33 of the insulating button 32 is created. Even at small lateral position inaccuracies of the expansion unit the switching conditions change relative to the power transmission practically not.

The complete snap mechanism can be used as an assembly on the base base 16 pre-assembled. The parts of the Snap switch on the base part 16 by plugging in corresponding slots and twisting of the tabs 19 and the twist tabs 17, 29 set. The one piece Bent sheet metal part very easy-to-use rocker switch 31 is pressed from above over the snap switch carrier and engages due to a snap lock formed by the lugs 51 there one. The insulating button 32 can be before or after the installation of the rocker switch on the mounting bracket 36 be placed, with a fastening against lifting off the tab 36 is not necessary because in the assembled Condition and operation of the assembled switch Button 32 is only subjected to pressure.

The filled and soldered component sensor / capillary tube / expansion socket 5 is attached to the retaining bolt 7. It can use standardized expansion elements or diastats be used as the expansion unit, except for the Need a pressure surface for the insulator 32 provide, not structurally adapted to the snap mechanism must become.

The adjustment is made using the adjustment screw 14. In operation, the setting shaft 8 for setting a certain temperature rotated so that the thread 9, 10th the expansion box 5 in a certain position along the Axis 60 of the adjusting shaft is brought. By this attitude the switching spring 21 is already more or less biased and more or less close to their switching point brought up.

When the temperature sensor 3 is warmed up, it expands Expansion fluid contained in the sensor and expands the Expansion box 5, so that the metal disc 35 after moves down and the lever 46 counter to that by the switching spring applied force pivoted clockwise.

The switching spring is supported in such a way that unloaded state of the switching spring the outer end with the Contact 25 is present on counter contact 27, i.e. the switch closed is. The one connected via the tabs Circuit is closed via the snap spring and the Switch is on.

If the switching point is exceeded by the fact that the switch spring moves down so far that it snaps and rests on the projection 26, then the Switch turned off. To the at this switching point on the Actuation point 47 occurring actuation force belongs, each after dimensioning and arrangement of levers and the corresponding Pressure points, one on squeezing the Bow legs 42, 43 directed limiting force. This in the area the tab 36 directed perpendicular to the legs, offset The force acting on the cutting edge bearing 50 is from the bow spring 41 transmitted without compression of the legs 42, 43, so that the entire rocker switch as a rigid actuator works.

In normal operation, after opening the contact 25, 27 no significant further expansion of the expansion box because the controller has responded and the sensor 3 heating of any electric heating device or other elements normally turned off becomes. However, if the user turns the adjusting shaft 8 by means of an operating button, not shown sets the controller to a lower temperature or it wants to switch off, he moves the expansion box continue in the direction of the rocker switch 31, that is, in the switch-off direction.

Now comes the anti-overpressure devices Temperature controller to effect. As long as the bow spring their limit force or buffer force has not yet been exceeded the bow legs 42, 43 cannot be compressed and the movement of the bow spring is a pure tilting movement. The limit force is set so that with another Overload the shift spring will continue to yield until the lever arm 46 rests on the stop 23. Also in this maximum overpressure state of the switching spring are on forces and deflections still act in the elastic Area of the switch spring, so that no permanent damage can occur. As the expansion continues, the Limit force exceeded and the previously rigid bow spring becomes resilient. It is squeezing the Give way 42, 43 and thus yourself and the Expansion unit and the parts of the temperature switch that support it protect against overpressure damage. The base part 16 or the switch spring support 22 may have recesses have, in which the tabs 55, 56 can dip, unless the surface level of the base part is constructive should already be deep enough. The maximum press-over distance the bow spring can by the height of the frame opening in the Tab be limited. This required amount in turn will of the maximum expansion or the maximum stroke of the Membrane predetermined.

When the overload is removed, e.g. when cooling the regulated Device, the expansion box 5 contracts and the strap spring 41, which acts as a buffer, returns to the Figures 1 to 3 shown initial shape with a defined maximum Opening width of the legs elastic back.

The buffer-lever unit created by the one-piece rocker switch 31 from shift lever 40 and buffer 41 is therefore one absolutely pressure-rigid in the operating state and only when overloaded yielding, but then exactly in his original form moving back one Power transmission between expansion socket and snap switch. The spring elasticity in this buffer only becomes effective if the switching has already taken place and is only for Overload protection primarily of the switching spring, but if necessary also the rocker switch itself and the expansion unit.

The embodiment of a temperature switch shown in FIG. 5 65 is distinguished from that shown in FIG. 1 Embodiment by a particularly low height. At 1 unchanged structure in the area of Base part 66 and the snap spring 67 and the same Construction of the one-piece rocker switch 68 is in this embodiment a flatter, electrically insulating ceramic body 69 provided that when the temperature switch is assembled with its domed top in punctiform pressure contact with a flat underside a metal disc 70 stands on the underside of a Flat membrane expansion socket 71 is present. In contrast to plate-shaped expansion box 5 according to FIG. 1 does that Capillary tube in the radial direction in the plane of the flat membrane directly into the inside of the corrugated, flat sheet metal halves the expansion box 71. Both the training of the Can as a flat membrane, as well as the lateral introduction of the Capillary tube 72 promote the particularly low overall height this embodiment, its assembly and function otherwise does not differ from the embodiment according to FIG. 1.

The embodiment shown in Figs. 6 and 7 one Temperature controller 75 differs from those before described embodiments essentially by the Shape of the one-piece rocker switch of the buffer-lever unit and by attaching the electrical insulation between Snap mechanism and expansion unit, you will the example an expansion unit with the edge bent upwards, Similar to Fig. 1 described, but it can also be a flat membrane can be used according to the type of membrane in Fig. 5. The The rocker switch 76 has the leg length essentially unchanged the bow spring compared to the ones previously described Embodiments of the U-bend 77 extended lever section 78, so that the cutting edge bearing 79 Support legs 80, 81 away from the adjustment axis 82 into the Area of the U-bend. In the area of the adjustment axis is one instead of the retaining tab for the insulating piece Dome-shaped upward expression 83 of the upper Bow leg trained.

The shift paddle from the expansion unit 84 is electrical insulating insulating piece 85 is not on the rocker switch attached, but is of a cross section of FIG. 7 easily recognizable bow spring 86 worn, the free Thighs on opposite, outwardly protruding Support the horizontal beads 87, 88 of the housing 89. The Insulator 85 has a flat bottom surface 89 with which it is supported point-by-point on the calotte 83 of the rocker switch, and an axial blind hole opening 90, in which is a bolt-shaped, vertical neck 91 on the underside the expansion unit 84 is inserted with a precise fit.

The insulating button 85 is thus by means of a resilient sheet metal part 86 axially pressed against the membrane 84 and is by its movable attachment to the housing part of the assembly assembly "Casing". If the bow spring together with the insulating piece in inserted the housing and subsequently also the expansion unit is installed, then one can by the bow spring 86th provided, upward axial preload any axial play in the area of the adjustment unit eliminate what can increase the setting accuracy.

When assembling the controller is in the area of the adjustment axis between the flat bottom 89 of the insulating body 85 and the integral dome acting as a sliding surface 83 of the rocker switch a pressure point 92 is formed. A functional corresponding pressure point exists in the previously described Embodiments between the flat bottom of the Expansion unit and the dome-shaped top of the Insulating piece. 6 and 7 is this pressure point lower, i.e. closer to the level of Cutting edge bearing 79. The cutting edge bearing is also further from the pressure axis coinciding with the setting axis 82 removed, so that between pressure point 92 and cutting edge bearing 79 formed lever arm of the rocker switch 76 in one clearly obtuse angle of approx. 60 ° to the pressure axis 82 stands as the corresponding lever arm in the embodiments 1 to 5. Correspondingly, the at the switching point, the tilting movement of the rocker switch with a sliding of the calotte 83 on the underside 89 accompanying transverse movement compared to the embodiments 1 to 5 clearly. By reducing the lateral movement, which in unfavorable cases due to canting or Interlocking of the parts that are slipping against one another must be impeded switching accuracy of the controller can be increased.

Common to all embodiments is the advantage that the unit created between the buffer and lever device this unit can be installed together and that the completion of a temperature controller alone Correct positioning of the housing normally already attached, if necessary over the housing-supported insulating piece isolated expansion unit on the buffer-lever unit can be done without the housing assembly with Diastat and if necessary, isolating piece with separate fasteners or measures attached to the buffer lever assembly should be. This allows all embodiments standardized diastats are used, which is the manufacturing cost lowers. The electrical insulation can Buffer lever unit, the housing or the expansion unit be assigned. The possibility of the snap mechanism with integrated Pre-assembling buffers also brings that Advantage that the actuation point through the snap system the clear pivot bearing of the lever is always exactly the same lies. Manufacturing tolerances in the position of the adjustment axis relative to the snap action because of the large area flat contact surface between the buffer-lever unit and the expansion unit or insulating piece not or only slightly the switching accuracy.

Claims (10)

Temperature switches, in particular adjustable temperature controllers, with an expansion element that has a Power transmission on a switch spring of a snap switch works, and with an overload protection for the Switch spring, the overload protection at least has a buffer with the power transmission interacts and that above one of the actuating force assigned to the switching spring in the switching point Limit force is changeable, characterized in that the power transmission and the buffer are one unit form. Temperature switch according to claim 1, characterized in that the power transmission is a lever device (30) with at least one lever (40), which preferably supported on one side in the manner of a cutting edge bearing and / or which has a lever arm (46), on the switching spring (21), preferably on one punctiform actuation point (47), acts. Temperature switch according to the preamble of claim 1, in particular according to claim 1 or 2, characterized in that that a stop (23) is provided on the a lever (40), in particular that on the switching spring (21) acting lever arm (46), after overcoming the switching point for the switching spring immediately supports, preferably the stop by a Projection (23) of a switch spring support (22) is formed becomes. Temperature switch according to one of the preceding claims, characterized in that the buffer at least a pre-tensioned, self-captivating in the direction of the spring Includes spring element, in particular in the form of a Direction of opening of your legs (42, 43) Stroke spring (41) with limited opening. Temperature switch according to claim 4, characterized in that the self-capturing spring element (41) on the Lever attached, in particular in one piece with the lever (40) is formed, preferably the self-captivating Spring element symmetrical between support legs (48, 49) of an L-shaped lever is arranged and / or that for self-restraint of the spring element at least one provided on a spring section Hook, especially one piece with one leg (43) of the bow spring (41) formed bending tab (55, 56) is provided, one on another spring section, in particular the other leg (42) provided Projection (57, 58) engages behind, preferably such that the hook (55, 56) under tension of the spring element on the projection (57, 58) supports. Temperature switch according to one of the preceding claims, characterized in that the structural unit from Buffers and power transmission, especially lever device (30), is a one-piece component, in particular a spring plate bent part. Temperature switch according to one of the preceding claims, characterized in that the expansion unit an expansion socket (5; 71) of a thermo-hydraulic Expansion system includes, preferably the Expansion box as a flat membrane expansion box (71) is formed and / or that the expansion unit, especially the expansion box (5; 71; 84), in the assembled State of the temperature switch in disconnected System contact with the unit from buffer and Power transmission or one movable on the housing (89) attached insulating piece (85). Temperature switch according to one of the preceding claims, characterized in that the structural unit from Buffers and power transmission electrically from the expansion unit is isolated, preferably via an insulating piece (32; 69; 85) made of electrical insulating, in particular ceramic material on the Expansion unit (5; 71; 84) is supported. Temperature switch according to claim 8, characterized in that the insulating piece (32; 69) on the Unit attached, in particular is attached or that the insulating piece (85) is movable on the housing (89) is attached, in particular one on the housing supporting spring element carrying the insulating piece (86) is provided that the insulating piece to the expansion unit presses. Temperature switch according to one of the preceding claims, characterized in that the expansion unit a flat contact surface (34; 89) is assigned to the the unit consists of buffer and power transmission, with a convexly curved support surface (33; 83) in supports essentially point-like.

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