Temperature-controlled device for switching off a heating installation
10886085 ยท 2021-01-05
Assignee
Inventors
Cpc classification
H01H35/24
ELECTRICITY
H01H37/12
ELECTRICITY
International classification
H01H37/12
ELECTRICITY
H01H37/36
ELECTRICITY
Abstract
A temperature-controlled device for switching off a heating device at a limit temperature has a thermo-mechanical temperature sensor device, a switch-off device, and manual reactivation means. The switch-off device has switching means which are activated by a trigger for switching off the heating device. The manual reactivation means have a movable handle and transmission means for transmitting a force of an operator for reactivating the switching means after switching off the heating device by the trigger. The transmission means have a click spring which at the beginning is in a basic position and, when an operating force acting on said click spring exceeds a certain limit force, clicks to a deflected position. Said click spring in the basic position enables reactivating or re-switching on, respectively, of the switching means. Said click spring in the deflected position releases so much movement path on the transmission means for the switching means that said switching means by the temperature sensor device and by the switch-off device above the limit temperature are activatable and switchable by the trigger.
Claims
1. A temperature-controlled device for switching off a heating device at a certain limit temperature, said temperature-controlled device having: a thermo-mechanical temperature sensor device; a switch-off device, manual reactivation means, wherein said thermo-mechanical temperature sensor device has: a thermo-mechanical temperature sensor; a trigger, wherein said switch-off device has switching means that, are activatable and switchable by said trigger, wherein said switching means is configured for installation in a path of an energy supply to said heating device, wherein said manual reactivation means has: a movable handle for transmitting an operating force of an operator for reactivating said switching means or re-switching on said switching means after switching off said switching means by said trigger; transmission means between said movable handle and said switching means, said transmission means being connected in a force-transmitting manner to said movable handle, wherein said transmission means has a click spring which in said line of said operating force that acts thereon from said movable handle, up to a certain limit force, is in a basic position as a first position and, when said operating force acting on said click spring exceeds said limit force, clicks to a deflected position as a second position; said click spring in said basic position reactivates said switching means or re-switches on said switching means; said click spring in said deflected position has a movement path on said transmission means for said switching means that said switching means by said thermo-mechanical temperature sensor device and by said switch-off device at a temperature above said limit temperature are activatable and switchable again for switching off said heating device by said trigger; wherein a trigger force exerted by said trigger in said temperature-controlled device acts counter to said operating force exerted on said movable handle by said operator, wherein said click spring is disposed in said force path between said trigger force and said operating force; and wherein a path differential between said basic position and said deflected position on said click spring is such that when said limit temperature is exceeded, said trigger exerts a trigger force on a trigger lever and a rocker so that said rocker moves counter to said click spring to switch off said switching means.
2. The temperature-controlled device according to claim 1, wherein a detent ring for a maximum movement path relative to said temperature-controlled device is provided for said movable handle.
3. The temperature-controlled device according to claim 2, wherein said detent ring is configured to extend from said movable handle towards a housing of said temperature-controlled device and at least partially engage across said transmission means.
4. The temperature-controlled device according to claim 1, wherein said click spring is planar or curved in one direction.
5. The temperature-controlled device according to claim 1, wherein said click spring is monostable, wherein said basic position is a stable position.
6. The temperature-controlled device according to claim 1, wherein said click spring is configured in such a manner that said limit force is less than said trigger force which has been generated by said trigger at a temperature beyond said limit temperature.
7. The temperature-controlled device according to claim 1, wherein said movable handle acts against and bears on said click spring.
8. The temperature-controlled device according to claim 7, wherein said movable handle is provided at a center of said click spring, wherein said click spring is planar or curved in one direction.
9. The temperature-controlled device according to claim 1, having a pressure arm, wherein said rocker has a rocker rotation point, and wherein said pressure arm is configured so as to be pivotable and is mounted in such a manner that said handle by way of said operating force acts on said pressure arm so as to move said pressure arm, wherein said pressure arm, when reactivating or re-switching on, is pushed against said rocker, wherein said rocker, by way of movement thereof, releases a movement path for said switching means so as to thus be able to close said switching means.
10. The temperature-controlled device according to claim 9, wherein said rocker is configured so as to be bistable and in a free position as a first position that does not activate said switching means is not influenced by said rocker, wherein said rocker in a blocking position as a second position forcibly opens said switching means and keeps said switching means opened.
11. The temperature-controlled device according to claim 9, wherein said trigger acts on said trigger lever by way of an increasing deflection of said trigger lever as said temperature rises at said thermo-mechanical temperature sensor, wherein said trigger lever is disposed between said trigger and said switching means.
12. The temperature-controlled device according to claim 11, wherein said trigger lever is disposed between said trigger and said rocker.
13. The temperature-controlled device according to claim 12, wherein said trigger lever, at an increasing temperature at said temperature sensor, pushes against said rocker in such a manner so as to push said rocker from said free position to said blocking position.
14. The temperature-controlled device according to claim 9, wherein said pressure arm has a main body which is configured for a force transmission of said operating force, wherein said operating force is a compressive force.
15. The temperature-controlled device according to claim 14, wherein said main body is configured as a double bridge having two longitudinal arms which extend in each case from an end, where said longitudinal arms are connected to said temperature-controlled device, wherein said longitudinal arms for connection therebetween have at least one transverse arm.
16. The temperature-controlled device according to claim 15, wherein said at least one transverse arm comprises two transverse arms that have a mutual spacing that is provided between said two longitudinal arms in such a manner that a free intermediate space is formed between said two transverse arms and said two longitudinal arms, wherein a bend of 70 to 110 is provided behind one of said two transverse arms or behind said click spring.
17. The temperature-controlled device according to claim 14, wherein said click spring is integrated in said transmission means in such a manner that said transmission means, said click spring and said main body are integrally formed by a sheet metal.
18. The temperature-controlled device according to claim 14, wherein said click spring is connected to said transmission means in such a manner that said click spring is connected to said main body in a form-fitting or materially integral manner.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Exemplary embodiments of the invention are schematically illustrated in the drawings and will be explained in more detail hereunder. In the drawings:
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DETAILED DESCRIPTION
(8) A deep fryer 11 as an appliance, or an electrical appliance, respectively, as has been described at the outset is illustrated in
(9) The afore-mentioned switch-off device 31 per se is composed mainly of switching means 38 in the form of an elongate and elastic switch spring 39 which is fastened at the right end thereof. Said switch spring 39 is advantageously also electrically contacted at said right end. The switch spring 39 at the left free end supports a contact head 40 by way of which said switch spring 39, on account of the pretensioning thereof, bears so as to push on a counter contact head 41 and closes the contact or the switching means 38, respectively. Since the switching means 38 here are very simple, but a switching procedure by way of the spring-elastic switch spring 39 is to be performed rapidly or abruptly, respectively, a transmission pin 37 is mounted so as to be longitudinally movable in the housing 21, on the one hand. Said transmission pin 37 bears on the switch spring 39 and in some circumstances can also be fastened thereto. The switching means 38 can be opened by means of said transmission pin 37. To this end, the switch-off device 31 has a rocker 33 which by means of a rocker rotation point 36 is mounted in the housing 21, wherein the mounting can be a so-called knife-edge mounting which is known per se. A left rocker arm 33a protrudes beyond the transmission pin 37. A rocker spring 35 which is flexed upwards under compressive stress is brought to bear against the end side of said rocker arm 33a that points to the left, said end side being notched. Said rocker spring 35 by way of the left end thereof is supported on a mount in the housing 21.
(10) A right rocker arm 33b of the rocker 33 is significantly shorter and supports an adjustment screw 34 screwed thereinto. The deflection of the rocker 33 in the position illustrated here, but above all also the activation thereof according to
(11) Rockers 33 of this type, or the entire switch-off device 31, respectively, for this purpose are also known from the prior art. The rocker 33 is obviously configured so as to be bistable. Said rocker 33 in the free position as a first position illustrated in
(12) In order for this movement of the rocker 33 now to be caused, a trigger lever 64 which at the left end thereof is pivotally mounted, for example also by way of an afore-mentioned knife-edge mounting, is provided between the rocker 33 and the diaphragm box 28. A downwards-pointing trigger protrusion 65, for example as a tab bent out in a downwards manner, is provided in the trigger lever 64. This trigger protrusion 65 in a movement of the trigger lever 64, or in the downwards pivoting of said trigger lever 64, respectively, pushes on the rocker 33, as described above. To this end reference is also made to
(13) The trigger lever 64 at the right end has in elongate and screw-fittable trigger detent 67. By way of the latter it can optionally be set how far the trigger lever 64 strikes from below on a part of the housing 21 where the afore-mentioned adjustment screw 34 can also impact in a downwards manner. The trigger lever 64, for example by way of a spring (not illustrated here), can furthermore be pulled upwards, or pivoted in a counter-clockwise manner, respectively, in such a manner that said trigger lever 64 at all times bears on the pressure protrusion 29 of the diaphragm box 28. Said trigger lever 64 can thus not push downwards against the rocker 33 in a self-acting manner and cannot undesirably influence said rocker 33.
(14) When the temperature in the fry pot 13 in the operation of the deep fryer 11 now rises, and the frying fat situated in the interior 14 of said fry pot 13 potentially reaches an excessive temperature, which can become very dangerous for reasons of spontaneous combustion, the temperature sensor device 22 intervenes. The expansion fluid in the sensor 25 and in the pipeline 26 expands specifically by virtue of the increasing temperature and herein in a known manner causes a downwards expansion of the diaphragm box 28 (i.e., the trigger). The pressure protrusion 29 pushes the trigger lever 64 downwards, or pivots the latter in the clockwise manner, respectively. At a specific point herein the trigger protrusion 65 comes to bear on the rocker 33 and pushes said rocker 33 downwards as the diaphragm box 28 increasingly expands. When a transition point as has been previously described of the bistable rocker 33 is exceeded herein, said rocker 33 clicks from the free position to the blocking position which is precisely illustrated in
(15) Since the heating device 16 is now switched off, the temperature in the fry pot 13 drops again, this being registered by the temperature sensor device 22. The expansion fluid increasingly contracts, the diaphragm box 28 consequently also being increasingly contracted towards the top. This can be seen in
(16) However, the rocker 33, by virtue of the bistable design embodiment thereof, remains so as to be pushed downwards in the blocking position according to
(17) The operator for renewed switching-on of the heating can now activate reactivation means 44 and to this end push a pushbutton 46 (i.e., a movable handle), as is visualized in
(18) As can be seen from the comparison of
(19) The pressure arm 52 at the left end has a spring region 54. The spring region 54 pushes the pressure arm 52 upwards, or causes a rotation in a counter-clockwise manner, respectively. This is achieved by the inherent material elasticity; the pressure arm 52 is advantageously composed of spring-elastic sheet metal.
(20) It can be seen from
(21) As is, a purposeful and safe state could have now been re-established, and the deep fryer 11 could continue to safely operate again, respectively. However, a look at
(22) As can be seen from
(23) In this downwards clicking of the click spring 57 a path of approximately 1 mm to at most 4 mm is traveled as soon as the click spring 57 after exceeding the transition point thereof clicks downwards to the deflected position. The diaphragm box 28 can now continue to expand, or by way of the pressure protrusion 29 move downwards without having to be pushed counter to a strong force. The click spring 57, configured so as to be monostable, by way of the restoring force thereof does indeed attempt once more to return to the original shape thereof according to
(24) The restoring force of the click spring 57 can even be so minor that said restoring force, in the case of the chosen lever ratios and the design embodiment of the rocker spring 35, is not sufficient for the right rocker arm 33b to be pushed downwards counter to the force of the rocker spring 35. The rocker 33, after the left rocker arm 33a has been pushed downwards by the trigger protrusion 65 of the trigger lever 64 by virtue of the expansion of the diaphragm box 28, thus remains in the position according to
(25) As can also be seen from
(26) It is only when an operator releases the pushbutton 46 that the latter can jump out to the position illustrated in dashed lines, specifically because the monostable click spring 57, by way of a central region 58 on which the lower side of the tappet 50 bears, then jumps upwards in a self-acting manner. The state of
(27) The click spring 57 on the pressure arm 52 can be better seen in
(28) The click spring 57 is placed on top of the main body 56, or is fastened thereabove. The click spring 57 has a curved central region 58 and four peripheral concavities 60a to 60d which therebetween have in each case one bearing foot 62a to 62d. The click spring 57 by means of said bearing feet 62a to 62d is fastened, advantageously welded, to the pressure arm 52 in the region of the main body 56.
(29) The side views of
(30) When a force F as aforementioned operating force, illustrated in
(31) A modification of a pressure arm 152 which also has two pressure arm ends 153a and 153b which point downwards towards the right and which are brought together in a main body 156 is illustrated in
(32) The design embodiment of such an integration of the pressure arm 152 and the click spring 157 in terms of construction and production is not that simple, but has the great advantage of greater integration. The welding of the click spring 57 to the main body 56, or to the pressure arm 52, respectively, according to
(33) The object of a permanent blockage of the switching-off of the heating device 16 in the deep fryer 11, potentially desired by an operator, being suppressed even when the pushbutton 46 for reactivating the switching means 38 is permanently depressed, or is held up to the detent, respectively, can thus be achieved by way of the invention. Appliance safety is thus maintained at all times.