Thermally triggered, mechanical switching device

Abstract

The invention relates to a thermally triggered, mechanical switching device, consisting of a heat-sensitive means and a mechanical force-storage means, wherein the heat-sensitive means blocks or unblocks the movement path of a switching piece; furthermore, the switching piece is preloaded and held by the mechanical force-storage means, and comprising a housing that accommodates the aforementioned means. According to the invention, the housing is designed as a cartridge-shaped shell which receives a plunger in the interior thereof, which plunger is mounted in a movable manner through a first end-side opening in the housing and is supported against a fusible shaping part under pretension, wherein the fusible shaping part is arranged so as to cover a second opening, which is located opposite the first end-side opening, in such a way that, when the melting temperature of the fusible shaping part is reached, said fusible shaping part is displaced by the plunger and the plunger takes on a changed position.

Claims

1. A thermally triggered, mechanical switching device, which comprises: a fusible shaping part and a mechanical force-storage means, wherein the fusible shaping part blocks or unblocks the movement path of a (3), the plunger (3) having a first end and an oppositely disposed second end; the plunger (3) further being preloaded by the mechanical force-storage means, and a housing that accommodates the fusible shaping part, the plunger and the mechanical force-storage means, wherein the housing is designed as a cartridge-like shell (1), which receives the plunger (3) in the interior thereof, wherein said plunger is mounted in a movable manner through a first end-side opening (7) in the housing and is supported against the fusible shaping part (4) under pretension, wherein the fusible shaping part (4) is arranged so as to cover a second opening (9), which is located opposite the first end-side opening, in such a way that, when a melting temperature of the fusible shaping part (4) is reached, said fusible shaping part is displaced by the plunger (3) and the plunger (3) takes on a changed position; wherein the plunger (3) is movable between a first position and a second position, the plunger (3) being in the first position if the melting temperature of the fusible shaping part (4) has not been reached, the plunger (3) moving to the second position if the melting temperature of the fusible shaping part (4) has been reached; wherein in the first position, the first end of the plunger (3) protrudes from the first end-side opening (7) and is operatively coupled to a first electrical switch or a first switching status indicator; and wherein in the second position, the first end of the plunger (3) is operatively decoupled from the first electrical switch or the first switching status indicator.

2. The thermally triggered, mechanical switching device according to claim 1, characterized in that the plunger (3) is provided with a collar (5) or a flange, against which a coil spring (2) acts as the force-storage means is supported.

3. The thermally triggered, mechanical switching device according to claim 1, characterized in that the housing has a tapered portion (6) with a reduced diameter in the direction of the first end-side opening (7).

4. The thermally triggered, mechanical switching device according claim 3, characterized in that the force-storage means is supported against the tapered part (6) in the interior of the housing.

5. The thermally triggered, mechanical switching device according to claim 1, characterized in that the plunger (3), after displacing the fusible shaping part (4), is movable with the second end penetrating the second opening (9).

6. The thermally triggered, mechanical switching device according to claim 1, characterized in that the fusible shaping part (4) is designed as a plug with respect to the second opening (9), the plug being located inside the housing and designed to close the second opening.

7. The thermally triggered, mechanical switching device according to claim 1, characterized in that, the housing is made of a thermally conductive material, wherein the device's response behaviour is settable or adjustable via the thermal capacity of the housing in conjunction with the material of the fusible shaping part (4).

8. The thermally triggered, mechanical switching device according to claim 1, characterized in that, the fusible shaping part (4) is made of an electrically conductive solder material, wherein the displaced solder material causes an electrical switching mechanism.

9. The thermally triggered, mechanical switching device according to claim 1, wherein in the second position, the second end of the plunger protrudes from the second opening and is operatively coupled to a second electrical switch or a second switching status indicator.

10. A thermally triggered, mechanical switching device, which comprises: a fusible shaping part (4) and a mechanical force-storage means, wherein the fusible shaping part (4) blocks or unblocks the movement path of a plunger (3), the plunger (3) having a first end and an oppositely disposed second end; the plunger (3) further being preloaded by the mechanical force-storage means, and a housing that accommodates the fusible shaping part (4), the plunger (3) and the mechanical force-storage means, wherein the housing is designed as a cartridge-like shell (1), which receives the plunger (3) in the interior thereof, wherein said plunger is mounted in a movable manner through a first end-side opening (7) in the housing and is supported against the fusible shaping part (4) under pretension, wherein the fusible shaping part (4) is arranged so as to cover a second opening (9), which is located opposite the first end-face opening, in such a way that, when a melting temperature of the fusible shaping part (4) is reached, said fusible shaping part is displaced by the plunger (3) and the plunger (3) takes on a changed position; wherein the plunger (3) is movable between a first position and a second position, the plunger (3) being in the first position if the melting temperature of the fusible shaping part (4) has not been reached, the plunger moving to the second position if the melting temperature of the fusible shaping part has been reached; wherein in the first position, the first end of the plunger protrudes from the first end-side opening; and wherein in the second position, the second end of the plunger protrudes from the second opening and is operatively coupled to an electrical switch or a switching status indicator.

Description

(1) Hereinafter, the invention is to be elucidated on the basis of an exemplary embodiment and utilizing drawings.

(2) Herein:

(3) FIG. 1 shows an illustration of the thermally triggered, mechanical switching device in a longitudinal section, having a plunger that is provided within a shell along with a preloading compression spring and a solder shaping part as fusible shaping part, wherein the end of the shell that is remote from the plunger is not yet crimped for fixing the solder shaping part while releasing a second opening;

(4) FIG. 2 shows an illustration similar to that of FIG. 1, but with a crimped shell end for fixing the solder shaping part and the remaining elements of the switching device;

(5) FIG. 3 shows an illustration of a switching device according to the invention, designed as a cartridge-shaped shell in the initial state, that is, before thermal heating;

(6) FIG. 4 shows an illustration similar to that of FIG. 3, but in a state after reaching the melting temperature of the fusible shaping part and successfully displacing the melted material out of the second opening along with a consequently changed position of the plunger;

(7) FIG. 5 shows a schematic diagram of the switching device according to the invention in a longitudinal section with a shell-like housing, plunger, spring-load means and peripheral contact or indication elements in a state of a not released switching device; and

(8) FIG. 6 shows an illustration similar to that of FIG. 5, but in a state after fusing of the fusible shaping part and displacing the plunger in the force direction F, while coming into contact with reference to an external indication or triggering element, for example, a status indication or a micro switch.

(9) The switching device according to the invention of the representative illustrations presupposes a cartridge-like shell 1, which preferably is made of a metal and thermally conductive material.

(10) The cartridge-like shell 1 has a predominantly cylindrical shape and accommodates a plunger 3 in its interior.

(11) The plunger 3 has a collar or a flange 5.

(12) Between the flange 5 and a tapered portion 6 of the shell 1, a force-storage means, which is formed as a compression spring 2, can be provided.

(13) The plunger 3 is arranged within the shell 1 transgressing through a first end-side opening 7 and is movable.

(14) The movement path of the spring-loaded plunger 3 is limited by means of a fusible shaping part 4.

(15) The fusible shaping part 4 is provided at an end of the shell 1, which is located opposite to the first end-side opening 7. The fusible shaping part 4 is secured inside the shell 1 via a crimping 8 (see FIG. 2), wherein in the area of the crimping 8 a second opening 9 remains, which is located opposite the first end-side opening 7.

(16) When the melting temperature of the fusible shaping part 4 is reached, the respective end of the plunger 3 displaces the molten mass of material. This leads to the plunger 3 moving to the left in the illustration according to FIG. 2 as a result of the preload force of the spring 2.

(17) Thus, the locking effect of the fusible shaping part 4 is cancelled when it is heated and changes to the fluid phase.

(18) The illustration of FIG. 3 shows the state with the solid fusible shaping part 4, while FIG. 4 shows how, over the course of the increase in temperature, the material of the fusible shaping part 4 passes through the second opening 9 and is practically displaced by the plunger 3, which in this case retreats into the interior of the shell 1, driven by the mentioned spring 2 and the operating spring force.

(19) By means of the illustrations of FIGS. 5 and 6 it is to be exemplified that, depending on the state of the fusible shaping part 4 and the position of a free plunger end 10 resulting from this state, the plunger is able to trigger, for example, a micro switch 11, that is, to either block that switch (see FIG. 5) or release it (see FIG. 6).

(20) Further there is the option that the plunger end 12, which has displaced the molten material of the shaping part 4, passes beyond the second opening 9 out of the shell 1 and triggers a micro switch or an indication unit 13 (see FIG. 6), which is released in the thermally non-activated state (see FIG. 5).

(21) The shell 1 can be a preformed component, which is closed by crimping after accommodating the spring and plunger as well as installing the fusible shaping part or a solder shaping part. With installing the solder shaping part or the fusible shaping part 4 in the still open shell, as shown in FIG. 1, at the same time, a loading of the compression spring 2 can take place. The respective compression spring load is sustained in the result of crimping the shell 1 (see FIG. 2).

(22) From the representative illustrations it is apparent that with heating, the fusible shaping part changes its aggregate state, wherein the plunger is triggered by means of the spring force, and the fusible shaping part material is displaced. From the change in position of the plunger, for example, a mechanical signal can be inferred or an electrical switch can be subject to triggering.

(23) In the shown embodiment the plunger can be pulled into the shell on one side and at the same time can be pushed out of the shell via the mentioned second opening.

(24) The emerging fluid solder, as shown in FIG. 4, can cause a contacting, for example, on a closely provided contact assembly, for example a circuit board.