ES2665828T3 - Electronic closing bulb - Google Patents

Abstract

Electronic locking cylinder (10) comprising a housing (24) that can be inserted into an opening of a mortise lock (12), a shaft (26) that is mounted in the housing (24) of the cylinder in a rotatable manner around a longitudinal axis (27) and which is integrally connected in rotation at an axial end with an actuating element (28), and a closing bit (30) mounted on the casing (24) of the cylinder in a rotatable manner around the axis longitudinally, an electrical assembly group and / or an electronic assembly unit (49) being arranged on the actuating element (28), characterized in that the shaft (26) is connected to the actuating element (28) via an element thermoprotective (60).

Description

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DESCRIPTION

Electronic closing bulb.

The present invention concerns an electronic closing bulb comprising a housing that can be inserted into an opening of a recessed lock, a shaft that is mounted on the bulb housing rotatably about a longitudinal axis and that is attached at one end. axially in a rotational manner with a drive element, and a closing blade mounted on the housing of the bulb rotatably around the longitudinal axis, an electric construction group and / or an electronic construction group being arranged on the drive element.

An electronic closing bulb of this class is known, for example, from DE 10 2005 034 618 A1.

The closing bulb includes a control circuit that is configured as an access control electronics and makes it possible to verify (verify the authenticity) of the access authorization of a person requesting access on the side of the drive element. The access control electronics then executes an exchange of data with an identity bearer (transponder) of the person requesting access. The transponder can be an active transponder or an active transponder that is coupled with an antenna of the construction group of the drive element, especially in a contact-free mode (for example, inductively or by radio). The construction group may include a suitable antenna for this purpose.

In the construction group is regularly contained a battery that can be based especially on lithium technology.

Whenever a closing bulb of this class must be incorporated in a fire protection door, a potential for danger is generally produced due to the battery disposed in the drive element. In case of fire, temperatures of much more than 200 ° C can be presented in the conventional electronic closing bulbs themselves, on the side of the door away from the fire. At such temperatures a battery may explode, such as a lithium battery, and / or a flame dart can be produced.

It is known in this respect the resource of housing a fire protection element that can be manufactured, for example, on the basis of an inflatable graphite in the actuating element. When temperatures of the order of magnitude mentioned above are reached, this fire protection element expands by increasing its original size several times, whereby the construction group is pressed out from the side of the fire. A bushing provided around the drive element and intended to form a knob can be pressed in this case out of an interlocked position with a flange element.

An electronic lock is known from WO 2010/144078 A1. The electronic lock is configured as a motorized lock and has a door fitting inside a door on which a battery is arranged. Also, an electronic printed circuit board is also arranged in the door fitting. It is proposed here to provide thermal insulation between one side of the motorized lock that faces the door and the printed circuit board and / or the lithium battery. In a variant, the battery is completely surrounded by thermal insulation. In another variant a thermal insulation is arranged between a lock plate, which borders the door, and a printed circuit board, a battery being mounted in an articulated manner in the motorized lock.

Against the background set forth above, a task of the invention is to indicate an improved electronic closing bulb that is especially improved with regard to fire protection.

This problem is solved with the electronic closing bulb mentioned at the beginning by the fact that the shaft is connected to the drive element through a thermoprotective element. With this measure it is achieved that especially the heat transmitted by the shaft is not transmitted as quickly or as strongly to the drive element. In addition, the thermoprotective element can be mounted in a relatively simple manner, since it is arranged especially outside the bulb housing and / or outside the actuator element. As a consequence, no major construction modifications are necessary with respect to closing bulbs that do not have to be incorporated in fire protection doors. Also, the drive element, which is specially configured as a knob, can also be of substantially identical construction to that shown in closing bulbs that do not have to be incorporated in fire protection doors.

Thanks to the thermoprotective element, the increase in temperature within the drive element can be clearly decelerated and / or the magnitude of this increase can be limited.

The thermoprotective element is specially configured (with respect to the material and / or with respect to the axial length and / or with respect to the diameter) so that the temperature inside the actuating element in a conventional fire test is kept below an allowable limit, especially below 250 ° C.

Consequently, the thermoprotective element forms a thermal resistance between the shaft and the element of

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drive

Thanks to the configuration of the closing bulb according to the invention, it is possible to dispense with fire protection elements within the drive element. In addition, the drive element can be fully configured in a closed and non-detachable form (a bushing can be joined with a flange section so that this bushing cannot be pressed out with the help of a fire protection element), so that security can also be increased eventually.

The electronic construction group within the drive element may be designed to establish a coupling with passive transponders that work, for example, with a frequency of 125 kHz or 13.6 MHz. However, it is also possible to equip the electronics with such functionality that a coupling with radio transponders or by other means of transmission (for example, capacitive or IR) is possible.

The closing blade of the electronic closing bulb can be connected to the shaft by means of different actor / clutch principles, preferably with an electromechanical clutch.

Therefore, the problem is completely resolved.

It is especially advantageous if the thermoprotective element is configured as a disk.

A disk of this class can be manufactured relatively easily based on thermally insulating materials and, in addition, can be housed between the shaft and the actuating element so that an aesthetically attractive mounting position can be realized.

According to another preferred embodiment, a diameter of the thermoprotective element is equal to an outer diameter of the shaft. Thus, for example, the same joining technique between the drive element and the shaft can be used as is also used in conventional closing bulbs (which are not designed for use in fire protection doors).

However, the diameter of the thermoprotective element can generally also be smaller and especially also larger than the outer diameter of the shaft.

Likewise, it is advantageous that the drive element has a flange element that is connected to the shaft through at least one fixing element.

A flange element of this class is an element with a larger diameter than that of the shaft and is preferably shaped in a disk shape and, in an assembled state, is located next to a door surface. The diameter of the thermoprotective element is preferably smaller than the diameter of the flange element.

The solidarity joint in rotation between the drive element and the shaft is realized by means of the union of the flange element with the shaft.

It is especially advantageous in this regard that the thermoprotective element has at least one passage hole for introducing the fixing element therethrough.

In this way, despite the arrangement of the thermoprotective element between the shaft and the fixing element, a mechanically safe and stable connection between the drive element and the shaft can be produced. It has been seen that the enabling of at least one through hole in the thermoprotective element does not have disadvantageous repercussions or only produces small disadvantageous repercussions as regards thermal insulation. The fixing element can be metal. Even in this case, a clearly better isolation of the drive element is achieved by means of the thermoprotective element. However, the fixing element can also be manufactured, for example, based on a thermally insulating material, such as plastic, ceramic or the like.

According to another preferred embodiment, the shaft is configured as a hollow shaft and is connected to the flange element through a plurality of screws that are distributed along the perimeter of the shaft.

The configuration of the shaft as a hollow shaft makes it possible to lay a power line from the drive element to a clutch in the bulb housing. The thermoprotective element preferably has correspondingly a passage hole for laying a power line of this class.

Likewise, it is advantageous for the drive element to have a bushing to house the electrical and / or electronic construction group, the bushing being connected at an axial end with the flange section (for example, by means of an insertion joint) and presenting in the another axial end a cover through which a coupling between the construction group and a transponder is made possible.

The bushing can be manufactured, for example, based on metal, while the cover can be manufactured, for example,

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based on a plastic or similar material that makes possible a coupling between the transponder and the construction group.

The coupling joint between the bushing and the flange section can be designed so that it is not possible to remove the bushing itself by means of a fire protection element.

Likewise, it is entirely advantageous for the thermoprotective element to have at least one axial projection to provide a secure mounting against rotation and / or against loss in the shaft.

In the shaft, more precisely on the front side of the shaft, a corresponding recess may be provided to receive the axial projection. The dimensions of the axial projection and the recess can be chosen so that the thermoprotective element can be connected to the shaft in a manner that is largely safe against loss, whereby the assembly assembly can be simplified.

Likewise, the union by means of conjunction in a peripheral direction between the axial projection and the recess in the shaft can also be configured to prevent a rotation of the thermoprotective element in the shaft.

Eventually, an axial projection of this kind may also be provided on an axially opposite side of the thermoprotective element so that it fits into a corresponding recess of the actuating element (especially a flange element thereof).

According to another preferred embodiment, the drive element has a fire protection element in a zone between the union with the shaft and the electrical and / or electronic construction group, which expands when heated above a predetermined temperature.

This fire protection element may eventually further improve the thermal insulation between a battery arranged in the drive element and the shaft.

A lithium battery is preferably a component of the electrical and / or electronic construction group. The shaft and the bulb housing are preferably made of metal. The same preferably applies to an outer section of the drive element that is preferably configured as a bushing.

The thermoprotective element is preferably made of a plastic, a Teflon material or a ceramic or a composite of such materials.

It is understood that the aforementioned characteristics and those that will be explained later can be used not only in the respective combination indicated, but also in other combinations or alone, without thereby departing from the scope of the present invention.

Examples of embodiment of the invention are represented in the drawing and are explained in more detail in the following description. They show:

Figure 1, a schematic view in longitudinal section through a door with an embedded lock and an embodiment of a closing bulb according to the invention in schematic form;

Figure 2, an exploded view of a part of another embodiment of a closing bulb according to the invention; Y

Figure 3, a perspective view of another embodiment of a closing bulb according to the invention.

In Fig. 1, a first embodiment of an electronic closing bulb is generally designated with 10.

The closing bulb 10 is configured as a profiled bulb and is inserted in a conventional manner in a recessed lock 12 which is incorporated in a door 14 that separates an outer side A from an inner side I.

The closing bulb 10 serves to actuate a latch 16 of the lock 12 schematically represented in Figure 1.

Also, the electronic closing bulb 10 is prepared to come into wireless contact with a transponder 18. The wireless coupling between the closing bulb 10 and the transponder 18 has been schematically designated with 20 in Figure 1. The coupling 20 can be of inductive nature, the transponder 18 being generally configured in this case as a passive transponder (for example, with 125 kHz or with 13.6 MHz). However, the coupling 20 may also be a radio coupling such as that used, for example, in some active transponders. In general, it is also imaginable that the coupling 20 works capacitively or infrared. Instead of a wireless contact, a coupling through a card reader device or the like is also imaginable.

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The closing bulb 10 has a housing 24 that is configured as a profiled housing (DIN profiled bulb).

A shaft 26 is pivotally mounted on the housing 24, axially projecting with respect to the housing 24. A drive element on the outer side in the form of an outer knob 26 is connected in rotation with the shaft 26 through a joint 29 (for example, a bolted joint).

In the housing 24, a closing pin 30 is also mounted in a conventional manner. The closing pallet 30 is hooked with the latch 16.

Between the closing blade 30 and the shaft 26, a clutch 32 shown schematically is mounted in the housing 24. The clutch 32 can be driven by means of an actuator arrangement 34 also schematically insinuated and arranged in the housing 24.

The clutch 32 can be, for example, an electromechanical clutch that is activated by means of an electrical signal and that can establish a joint by form conjunction or a friction joint between the shaft 26 and the closing pin 30.

The closing bulb 10 also has a control device. The control device includes, for example, an external or external control section 40 which is mounted on the external knob 28. A battery 42 and an antenna 44 are also mounted on the external knob 28. The external control section 40 it includes a reception circuit 46 that is connected to the antenna 44 (reception element), as well as an evaluation circuit 48. The evaluation circuit 48 is connected to an output of the reception circuit 46.

The control device also includes, for example, an internal control section 50 which is arranged inside the housing 24, specifically, seen from the outer side A, behind an anti-drilling protection 52 optionally provided also in the housing 24.

The anti-drilling protection 52 may be configured in a manner known per se, for example by means of a plurality of hard metal rods that run transversely to the longitudinal axis, by means of a hard metal plate or the like.

The inner control section 50 is connected to the evaluation circuit 48 by means of an electric line 54. The electric line 54 is laid through the shaft 26 configured as a hollow shaft. The hollow shaft 26 runs through the anti-drilling protection 52. Also, another hollow protection section 53 can be provided in the hollow shaft 26 which rotates together with the shaft 26.

The internal control section 50 is also connected to the actuator arrangement 34 and is designed to activate this actuator arrangement 34 (supply it with an activation signal 55). As soon as the activation signal 55 reaches the actuator arrangement 34, the clutch 32 is closed. The activation signal 55 can be applied, for example, by supplying electric current to the actuator arrangement 34.

The general operation of the electronic closing bulb 10 is as follows.

In the state of rest of the electronic closing bulb, the clutch 32 is open. The outer knob 28 and the shaft 26 are freely rotatable in relation to the housing 24. Therefore, persons who do not have an access authorization in the form of a Valid transponder (with a valid identification code) cannot open door 14 from the outer side A.

The electronic closing bulb 10 is configured as a semi-bulb there is no possibility of actuating the closing blade 30 from the inner side I. It is imaginable in this respect that the door 14 is configured as an escape door, the lock can always be opened 12 from the inner side I, for example by pressing down a door latch that also drives the latch 16. The electronic closing bulb 10 can also be configured as a double bulb. In this case, a closing pallet can be rigidly connected with another shaft that, for example, is joined in a solidary manner in rotation with an inner knob.

Whenever a person with an authorized transponder 18 requests access, a data exchange between the transponder 18 and the external control section 40 is carried out through the coupling 20 and the antenna 44. In this external control section 40 the authenticity is checked of the transponder 18. In other words, it is evaluated in the external control section 40 if an authorization signal transmitted by the transponder 18 (with an identification code contained therein - for example, modulated on it) authorizes to perform at the door 14 a closing process, that is, for example, unlocking the latch 16.

As long as transponder 18 does not transmit a valid authorization signal 20, the process is interrupted.

Provided that the authenticity of transponder 18 is confirmed (that is, transponder 18 carries a code of

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valid identification), the external control section 40 delivers a code signal to the internal control section 50 via line 54, the code signal including an identification code.

The identification code can theoretically be the same as the identification code of the transponder 18. However, it is generally a simpler code in the form of a binary code with, for example, 32 bits.

The identification code transmitted to the internal control section 50 may be a code fixedly programmed for the individual closing bulb 10. However, it is also possible that the identification code is generated by means of a so-called master transponder, specifically configured as a specific 32-bit key of the bulb to establish communication between the external control section 40 and the internal control section 50. In this "programming process" the code is stored stably in the internal control section 50. A reprogramming only through a new use of the master transponder, and a new identification code can also be programmed.

The identification of the identification code with 32 bits should only be understood as an example. It is understood that the number of bits may also be smaller or larger, for example in the range of 16 to 64 bits.

Also, the code can also be configured as a change code that is changed with each new closing process. This naturally requires more expensive communication between the inner and outer control sections 50, 40.

In addition, it is also possible that security is further increased, specifically with the help of additional authentication mechanisms (for example, in the form of the so-called "mutual authentication"), a random number that is multiplied is used for encoding or decoding, for example, by the binary code. The random number can be based on a pseudostatic system, the same pseudostatic sequence of random numbers being archived in both the external control section 40 and the internal control section 50, whereby a synchronization is performed without it having to be transmitted to through line 54.

When, after receipt of a valid authorization signal 20, the external control section 40 sends, by means of transponder 12, a code signal with the identification code to the internal control section 50, the code is then decoded there code signal (for example, it is compared to the binary code stored there). Whenever the identification code received in the code signal is considered valid in the internal control section, the activation signal 55 is delivered to the actuator arrangement 34 and thus the clutch 32 is closed. The pallet can then be operated. of closing 30 by means of the external knob 28 to thus carry out a closing process.

Actuator arrangement 34 activates clutch 32, for example for a predetermined time interval of a few seconds. After the time interval has elapsed, the clutch 32 is automatically opened again, thereby restoring the idle state.

The inner control section 50 and the actuator arrangement 34 are located, together with the closing blade 30, behind the anti-drill protection 52, 53, specifically seen from the outer side A.

Even if the external knob 28 is removed without authorization, the actuator arrangement 34 cannot then be operated by means of a power supply to, for example, the power line 54. Indeed, to generate the activation signal 55 it is necessary that the indoor control section 50 receives the code signal with the valid identification code.

Therefore, manipulation from the outer side A is excluded, particularly in spite of the arrangement of a predominant part of the control device on the outer knob 28.

Upon receiving a valid authorization signal 20, a signal emitter 56 can be activated in the electronic closing bulb 10 of FIG. 1 indicating by means of an optical and / or acoustic signal that a valid authorization signal has been received.

The internal control section 50 is configured as a kind of electronic safety circuit inside the housing 24.

In the area of the junction 29 between the shaft 26 and the outer knob 28 a thermoprotective element 60 is arranged. More precisely, the shaft is connected to the outer knob 28 through the thermoprotective element 60. In case of a fire in the inner side I, the heat production can be so great that heat is transported in the direction of the outer knob 28 through the housing 24 and the shaft 26. Thanks to the thermoprotective element 60, which acts as a thermal resistance, it can be achieved that the temperature increase inside the external knob 28 is carried out clearly more slowly and is eventually limited to a temperature that is smaller than a danger temperature at which, for example, the battery 42 could explode. The battery 42 is configured

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55

preferably as a lithium battery and, therefore, is especially sensitive to a heat action.

In addition, a schematically insinuated fire protection element 62 can be arranged inside the outer knob 28 that is materialized, for example, based on inflatable graphite. The fire protection element 62 expands in case of fire with heat production and contributes to a thermal insulation of especially the battery 42 and possibly also of the control section 40.

Consequently, the closing bulb 10 of Figure 1 is suitable for incorporation in fire protection doors. The closing bulb 10 of Figure 1 is configured as a so-called semi-bulb, but it can also be configured as a double bulb. In this case, the housing 24 can extend to the inner side I. The closing blade 30 can be rigidly connected with an additional shaft that extends to the inner side I and is there joined in a solidary manner in rotation with an inner knob. In this case, the door 14 can always be opened from the inner side I by means of the inner knob.

In a double bulb of this class the heat produced as a result of a fire on the inner side can be propagated to the outer knob 28 through the inner knob and the additional shaft, as well as through the housing 24 and the shaft 26, with which in this case may eventually be of even greater importance the use of the thermoprotective element 60.

In figure 2 an exploded part of another embodiment of a closing bulb 10 is shown in exploded view. The closing bulb 10 of Figure 2 generally corresponds to the closing bulb of Figure 1 as regards its constitution and operation. Therefore, the same elements are provided with the same reference symbols. In the following, details of the differences will be substantially entered.

The closing bulb 10 of Figure 2 has an external knob 28 showing a flange element 66 next to the door. The diameter of the flange element 66 is larger than the diameter of the shaft 26. The flange element 66 is attached with the shaft 26 through a plurality of fasteners in the form of screws 68. To this end, a plurality of threaded holes 70 (in this case, four threaded holes) is provided on a terminal front surface of the shaft 26. Likewise, a corresponding plurality of through holes 72 are provided in the flange element 66 through which the stems of the fixing elements 68 can be connected.

The external knob 28 also has a support 74 of the construction group. The support 74 of the construction group has a substantially cylindrical shape and is surrounded by a metal bushing 76 also made in a substantially cylindrical shape. The bushing 76 can cooperate at an axial end with an engaging means 78 disposed on the outer perimeter of the flange element 66 to thereby immobilize the bushing 76 against the flange element 66. At the axially opposite end the bushing 76 is closed by a cover 80 which makes possible a coupling between a transponder and the antenna provided as an annular antenna 44 which, in the assembled state, is covered by the cover 80. This cover 80 is preferably made of a plastic or similar material to make this possible. coupling The transponder is preferably an inductive transponder or a radio transponder and is designed to provide a contactless coupling with the antenna 44.

The support 74 of the construction group includes a compartment for receiving the battery unit 42, which may preferably have two individual batteries. The battery unit can be connected through a plug-in connection with a control section 40 that is also immobilized on the support 74 of the construction group (which is not shown in Figure 2 for reasons of a clearer representation).

Between the support 74 of the construction group and the screw heads 68 there is a fire protection element based on inflatable graphite, which in this case is configured as a disk. On the side of the flange element 66 that is turned towards the support 74 of the construction group, a plurality of recesses 82 are also distributed distributed around the perimeter, which are configured as blind recesses and into which fire protection elements can also be inserted correspondingly. configured in the form of a circular segment.

Between the terminal front side of the shaft 26 and the flange element 66 a thermoprotective element 60 is arranged in the form of a relatively flat disk. The thermoprotective element 60 has a plurality of through holes 83 through which the screw shanks 68 can extend. Likewise, the thermoprotective element 60 has at least one axial projection 84 on the axial side turned towards the shaft 26 which can fit into a corresponding cavity 85 on the outer side of the tree 26 in order to achieve an anti-rotation or loss insurance.

The axial projection 84 may be eccentrically made with respect to the longitudinal axis 27. In the present case, the axial projection 84 is configured as an axial pin. Alternatively or additionally, an axial projection 84 'may be configured in the form of a circular segment that fits into a corresponding cavity 85' for the same practiced on the front side of the shaft 26.

The shaft 26 is configured as a hollow shaft, and a passage hole is formed in the flange element 66

central (not specifically designated in figure 1). Through this, an electric line can be laid that joins a control section 40 of the outer knob 28 with an inner control section 50 of the closing bulb 10. Correspondingly, the thermoprotective element 60 preferably also has a central passage hole for lay a power line of this kind through it.

5 The screws 68 may be made of metal, but they may also be made of plastic or ceramic or the like.

The shaft 26 and the flange element 66 are preferably made of metal. The bushing 76 is also made of metal, the cover 80 being made of plastic or the like. The support 74 of the construction group is preferably made of plastic.

Figure 3 shows another embodiment of a closing bulb 10 which generally corresponds to the closing bulb 10 of Figure 2 as regards its constitution and operation. Therefore, the same elements are identified by the same reference symbols. In the following the differences are explained substantially.

The closing bulb 10 of Figure 3 is configured as a double bulb and, in the direction of the outer side A, is constructed identically to the closing bulb 10 of Figure 2. In Figure 3 the closing bulb is shown. 10 in assembled state.

The housing 24 is configured as a profiled bulb housing and has a ribbed section 86 extending in the longitudinal direction, through which a bore 88 is formed for a cap screw (in transverse or oblique direction with respect to the longitudinal axis ).

Also, the housing 24 has a first annular section 90 in which the shaft 26 is rotatably mounted 20. The housing 24 also has a second annular section 92 offset in the direction of the inner side I, in which an inner shaft 94 is rotatably mounted. The inner shaft 94 is joined in a integral manner in rotation with the closing pin 30, which It is also rotatably mounted on the housing 24. The inner shaft 94 is joined in a integral manner in rotation with an inner knob 96.

Claims (11)

5 10 fifteen twenty 25 30 35 1. Electronic closing bulb (10) comprising a housing (24) that can be inserted into an opening of an embedded lock (12), a shaft (26) that is mounted on the housing (24) of the rotating bulb around of a longitudinal axis (27) and which is joined in a solidary manner in rotation at an axial end with an actuating element (28), and a closing pin (30) mounted on the casing (24) of the light bulb rotatably around of the longitudinal axis, an electrical construction group and / or an electronic construction group (49) being arranged in the drive element (28), characterized in that the shaft (26) is connected to the drive element (28) through a thermoprotective element (60). 2. Electronic closing bulb according to claim 1, characterized in that the thermoprotective element (60) is configured as a disk. 3. Electronic closing bulb according to claim 1 or 2, characterized in that a diameter of the thermoprotective element (60) is equal to an outer diameter of the shaft (26). 4. Electronic closing bulb according to any one of claims 1-3, characterized in that the actuating element (28) has a flange element (66) which is connected to the shaft through at least one fixing element (68 ). 5. Electronic closing bulb (60) according to claim 4, characterized in that the thermoprotective element (60) has at least one passage hole (83) for introducing through it the fixing element (68). 6. Electronic closing bulb according to claim 4 or 5, characterized in that the shaft is configured as a hollow shaft and is connected to the flange element (66) through a plurality of screws (68) which are distributed therein tree perimeter length (26). 7. Electronic closing bulb according to any of claims 4-6, characterized in that the actuating element (28) has a bushing (76) for housing the electrical and / or electronic construction group (49), the bushing being connected ( 76) at one axial end with the flange section (66) and at the other axial end presenting a cover (80) through which a coupling between the construction group and a transponder (18) is made possible. 8. Electronic closing bulb according to any one of claims 1-7, characterized in that the thermoprotective element (60) has at least one axial projection (84) for a secure mounting against rotation and / or against loss in the shaft (26 ). 9. Electronic closing bulb according to any one of claims 1-8, characterized in that the actuating element (28) has an area between the joint (29) with the shaft (26) and the electrical construction group and / or electronic (49) a fire protection element (62) that expands when heated above a predetermined temperature. 10. Electronic closing bulb according to any of claims 1-9, characterized in that the shaft (26) is made of metal. 11. Electronic closing bulb according to any of claims 1-10, characterized in that the thermoprotective element (60) is made of a plastic, Teflon or a ceramic.