DE2327043A1 - THERMAL TRIGGER - Google Patents

Description

Patent attorneys

Dipl.-Ing. Helmut Missling 63 Giessen 15 * 5.1973 Dipl.-Ing. Richard Schlee Bismarokstrasse 43

Dr.-Ing. Joachim Boeck er Phone: CO641) 71O19

Boe / K 11,589

Allmänna Svenska Aktiebolaget Vasteras / Sweden

(Thermal trigger

The present invention relates to a thermal release with a bimetallic organ that is directly or via a Trigger organ an electrical contact organ., E.g. "in one Relay or load switch, affected

In known thermal releases, the bimetal elements usually have the form of elongated strips, one of which End is firmly clamped, while the other end slowly bends when heated and, for example, a lock in A switch mechanism influenced Such a construction is not only afflicted with technical disadvantages, but turns out to be relatively expensive ^ since it is a relatively requires a large amount of the expensive bimetal material. One must use relatively thick material in order to obtain the required force. The bimetal will go bad exploited, as its curvature is only used in one direction

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will. The "well-known construction also proves itself when operated often as unreliable, especially if the Sρerranordnung influenced by the bimetallic organ Wear shows what leads to changed frictional resistance. The ordinary bimetal spring does not react with a sudden movement, but one receives a weak, long-lasting effect on the arrangement, which is to be influenced by the spring "

The present invention has for its object to be a to develop thermal release of the type mentioned, which does not have the disadvantages mentioned of the known Aus. Solvent is afflicted, but a simple space-saving one Has structure and enables a reliable, defined switching process.

A thermal release is used to solve this problem Proposed type mentioned at the outset, according to the invention is characterized in that the bimetallic organ consists of a there is a disc arched on one side which, when heated, arches on the opposite side, with the Transition of the bulge from one side to the other unstable deformation area abruptly, is passed, and that the disc with one in the same direction of movement.

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acting everyone connected iso

Among the benefits of the release according to the invention over the known working with bimetal spring triggers include u _o a <>.

a) You save bimetal material because with a thin one Disc a relatively large force is generated.

■ b) Better use is made of the material of the bimetal. One namely, curved disc is ideal for the way of working of the bimetal, as the change in shape of the entire bimetal surface can be used and not just the curvature in a single direction.

c) A mechanism that works suddenly is obtained, because the bimetal disc suddenly moves from the curvature on one side to the curvature on the other Page folded. .

d) The spring helps when the trigger is actuated in one direction and, together with the

^: Bimetal disc has a relatively large spring force. This makes "a more reliable operation".

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e) The trigger becomes relatively insensitive to vibrations and shocks.

f) The trigger can be a moving contact directly influence, since it develops a relatively large force in the direction in which the spring with the bimetallic

'tall disc worked together

g) The release can easily be supplemented with magnetic overcurrent protection.

The invention is to be explained in more detail on the basis of the exemplary embodiments shown in the figures. Show it:

Jig. 1 and 2 a first embodiment of the invention, where Pig .. 1 shows the release in section from the side and FIG. 2 shows a top view,

Pig. 3 and 4 corresponding representations of a second Embodiment in which the release is supplemented by magnetic overcurrent protection.

The releases shown in the drawing consist of a thin curved disc 1 made of bimetal, which is screwed

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"Be 2 and nut 3 are connected with a leaf spring 4» The bimetallic sole _{plate 1, which can have a thickness of Z 0} B ₀ O ₉ 3 mm, is attached to a base plate 5 made of electrically conductive material, which is in series with an electrical conductor whose! temperature is to be recorded. The trigger. can, however, also be mounted directly on the electrical conductor, especially if it has the shape of a rail the base plate '5 or. directly against the current-carrying rail "

The bimetallic disc 1 works in such a way that it changes when there is a change the temperature also change the curvature and spring force of the disc «In the starting position, dia in the drawing is shown, the force of spring 4 and the spring

force of the disc 1 against each other. At a higher temperature the disc, the counterforce of the disc decreases and in a certain position it falls below the force of the spring 4 »whereby the disk arrives in an unstable deformation area which it jumps through, see the Force of the disk added to that of the spring The bimetallic disk 1 so to a certain extent snaps from the curvature one side into the curve to the other side,

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When / the temperature has dropped again, the trigger may manually reset with a force directed against the spring 4 will.

The trigger can be made to snap at a certain temperature by turning the screw 2 or the nut 3 through a certain angle the same ₀ , which is provided, for example, for the contact arrangement of a relay. If an actuator with a longer stroke length is required, this can be achieved with a lever arm 7 (Pig. 3) with which the movement of the bimetallic disk 1 can be increased.

The domed pear-shaped disk 1 jumps at a certain point Pressure of the steel spring 4 and at a certain temperature of the bimetal disc 1 to. This gives you a sudden and switching on the contact arrangement, and a special snap mechanism is thus no longer required for this purpose necessary. ■

With smaller circuit breakers or the like _o which are to be provided with over-current protection, the lever arm 6 can (Figo 3)

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the "moving contact of the switch and the bimetal disc 1 form the switch mechanism «, With larger load switches, the lever arm 7 can be used to lock in the To influence the snap mechanism of the switch.

From Fig. 3 and 4- it can be seen in the rest of how the thermal release according to the invention in a simple manner with a Arrangement for magnetic overcurrent release can be combined. This arrangement consists of one around the conductor 5 arranged around bracket 8 made of steel, which attracts the lever arm 7 when the current in the conductor a certain Value exceeds «.

For compensating the outside temperature of electrical conductors You can either produce the spring 4 from bimetal or reinforce the spring 4 with a spring 'made of bimetal.

A thermal release, the version shown, can be used in can be used in many different contexts. Its area of application therefore not only includes the measurement of Temperatures in electrical conductors, but the trigger can also be used with advantage to measure temperatures in others Arrangements are used. It can also be the air temperature of the room in which the trigger is located.

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The invention is not restricted to the exemplary embodiments shown, but can be varied in many ways. For example, a helical spring can be used instead of the leaf spring 4. Further, the bimetal disc does not have to be round, but can in principle have any other convenient shape, such as ₀ to a rectangle.

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Claims (1)

Claims; M ₀ ] Thermal release with a bimetallic element which, directly or via a tripping element, influences an electrical contact element, for example in a relay or load switch, characterized in that the bimetallic element (1) consists of a disc which is curved on one side and which is at Warming up after the. opposite side arches, whereby at the transition of the arching from one side to the other an unstable area of change in shape is suddenly passed, and that the disc (1) is connected to one each (4) acting in the same direction of movement. 2. Trigger according to claim 1, characterized in that the thickness of the bimetal disc (1) is at most 0 (5 mm). 3ο release according to claim 1 or 2, characterized in that that the bimetal disc (1) is round " 4. Trigger according to one of claims 1-3 »characterized, - that the spring (4) cooperating with the bimetal disc (T) is a leaf spring. -10- 309850/0941 -ίο- ·? 327043 5. Trigger according to one of the preceding claims, characterized in that for connecting the bimetal disc (1) A connecting element (2, 3) is used with the "spring (4)", which has one approximately in the middle of the bimetal disc fastened and substantially at right angles to this directed bolt or pin contained 6. Trigger according to claim 5, characterized in that the connecting member (2, 3) is such that the Distance between its contact points on the bimetal disc (1) and the spring (4) is adjustable. 7. Trigger according to claim 6, characterized in that the connecting element consists of a screw (2) and a nut (3). 8. Trigger according to one of the preceding claims, characterized in that the of the bimetal disc (1) influenced contact or trigger element is a lever arm (7). _. - 9ο trigger according to one of the preceding claims, characterized characterized in that it responds with an overcurrent magnetic trigger element (7, 8) is provided. 309850/0941 7327043 10. Trigger according to claim 9, characterized in that the magnetic trigger element (7, 8) from one to one '' Live rail (5) in the magnetic circuit arranged in the release (Core and anchor), the anchor of which consists of the mentioned contact or trigger element ". 309850/0941 4 * Blank page