DE1088129B - Magnetically operated mercury switch of small dimensions - Google Patents

Description

GERMAN

The invention relates to one operated by a magnet Mercury switch with switching vessel closed on all sides and small dimensions.

In a known embodiment of such a switch are on a closed cylindrical Vessel cover with constant diameter attached at right angles to two pole pieces of a relay. in the The vessel is a cylindrical piston, between the * bottom and the bottom of the vessel Spring is inserted. There is a mercury ball on the flask, which, due to its surface tension, does not enter the small gap between the piston and Sheath can penetrate. Two electrodes are inserted through the upper end of the vessel, one of which is the one is normally immersed in the mercury globule while the other is some distance away of the mercury. When the pole pieces are energized, the piston is pulled upward and bringing the mercury bead into contact with the second electrode. That kind of shawl ter are quite insensitive, since the flask and mercury drops from the magnetic field around the same Must be moved away until it touches the second electrode.

With a similar switch, the vessel is almost half filled with mercury. Above the A coil of wire is wound around the vessel at the level of mercury; the magnetic field that passes through you current flowing through this coil is generated, actuates a magnetic displacement body floating in the mercury, the mercury passes through its central opening. When the sinker is sufficiently submerged, so much mercury has leaked up through the central opening, that it touches a contact and a line for the current is established. The disadvantage of this well-known Switch is also in the fact that it is relatively insensitive is; when the displacement body is actuated, a relatively large amount of mercury must be used be conveyed through the central opening before contact is made with the contact. aside from that the well-known switch is quite sensitive to position; if it is not nearly a vertical position takes, it either does not switch at all or changes its sensitivity quite considerably.

Another switch is known, in whose cylindrical shell a displacement body on the mercury, floats, which is drawn into the mercury with magnetic excitation and this in the gap formed between it and the shell up into contact with one or two Drives contacts, which are arranged in separate upper chambers. The disadvantage of this switch is the considerably long way, that of the mercury with Be magnetically operated mercury switches of small dimensions

Applicant:

Robertshaw-Fulton Controls Company, Richmond, Va. (V. St. A.)

Representative: Dr.-Ing. W. Reichel, patent attorney, Frankfurt / M. 1, Parkstrasse 13th

Claimed priority: V. St. v. America April 26, 1957

Roy Walter Hauser, Los Angeles, Calif. fV. St. A.), has been named as the inventor

actuation of the displacement body within the gap must be covered.

In the case of a magnetically operated mercury switch with two fixed contacts within an upper chamber of the housing and with a displacement body, the central opening of which acts as a connecting channel to the upper one Chamber is formed, further with a device located outside the housing, which the displacement body actuated magnetically, are according to the invention the diameter of the upper chamber and the of the connecting channel made so small that the surface of the mercury located therein is strong is arched, while the lower chamber and the displacement body provided for a small stroke however, have a relatively large diameter.

In building this arrangement, a capsule and a lid, both of which are made from a non-ferrous Fabric are made airtight together, so that a housing with a small, upper chamber for two separate electrodes and with a relatively large, lower chamber for the mercury mass will. An iron armature with an opening and a relatively low specific weight floats on the mercury mass, while a corrugated spring ring is submerged in the mercury and helps hold the anchor. The one known per se, possible within adjustable limits

009 589/335

Movement of the permanent magnet, which is attached to a condition responsive lever outside of the housing, changes the magnetic flux acting on the armature. An increase in the magnetic flux shifts the armature into the mercury, which in the process rises through the small opening of the armature, so that the strongly curved mercury level in the upper chamber conductively connects the electrodes; When the magnetic flux decreases, the armature returns to the floating position on the relatively denser mercury, the spring force exerted by the elastic spring ring enabling a snap movement of the armature. Such a construction has unique advantages in the economical production of precision mercury switches whose size and position dependency are relatively small and whose response sensitivity is high, 1

Other features and advantages are evident from the following Description of a. Embodiment of the invention clearly evident from the figures.

Fig. 1 is a front view of a mercury switch according to the invention;

Fig. 2 is a view similar to Fig. 1 with certain parts in section and the switch in its are shown in the open position;

Figure 3 is a view similar to Figure 1 showing the switch in its closed position.

In the figures, a switch housing 10 is closed with an upper cover cap 12 made of an ice-free material see, the airtight connected to a lower cup-shaped capsule 14 made of an iron-free material is. The interior of the capsule 14 forms a swimming chamber 16; the inside of one in the middle Essay 18, which with the cover plate 12 from a Piece consists, is pierced and forms an electrode chamber 20. As can be seen in Fig. 2, the The volume of the swimming chamber 16 is significantly greater than that of the electrode chamber 20. Two electrodes 22 are inserted airtight into the attachment 18 of the cover plate, with their inner ends in the same End height and have a certain distance from each other in the electrode chamber 20; at their outer ends are two lead wires 24, e.g. B. with solder points 26 attached.

A certain amount of a liquid conductor, e.g. B. mercury 30, is in the lower part of the capsule 14 so that the mercury 30 only partially fills the swimming chamber 16. A movable anchor 32, which consists of a magnetic iron ring, is movably fitted within the side surfaces of the chamber 16 and equipped with a concentrically arranged opening 34. The top and bottom surfaces of the Anchor rings 32 run uniformly radially from the inner edge of the opening 34 to the outer edge of the armature outwards apart. Even if 32 different magnetizable substances are used for the armature ring can be, its density and special dimensions must be chosen so that it is on the liquid mercury floats. A corrugated, resilient ring 36 is between the underside of the armature 32 and the bottom of the swimming chamber 16 is immersed. In its free, wavy form is the diameter of the spring ring 36, as in; Fig. 2 can be seen, smaller than the swimming chamber 16j so that under mechanical Pressure flattening of the spring ring 36 is possible. Normally, the spring ring 36 cooperates with the buoyancy of the mercury 30 on the armature 32, so that it is held floating will. _ ■ "" · ■ '-'. .

Outside the switch housing 10 is one end of an actuating part in a manner known per se 40, e.g., a bimetal strip, fixed in a suitable socket (not shown). One on the anchor 32 acting permanent magnet 42 is, as is also known per se, rigid at the free end of the bimetal strip 40 and provided with an adjustment screw 44. This is through the bimetal strip 40 and screwed through the center of the magnet 42 and has a stop end 46 that with the outer Bottom surface of the capsule 14 can come into engagement.

Housing 10 and magnet 42 are individually housed within a common socket (not shown) in FIG fastened to one another in such a position that the magnet 42 is aligned with the housing 10. Of the Switch according to this special embodiment is actuated when the temperature changes. When the magnetic Force the resulting force from the spring action of the ring 36 and the buoyancy of the mercury 30 exceeds, the armature 32 is attracted to the magnet 42, the corrugated spring ring 36 is compressed. It should be noted that the final movement of the armature 32 is a snap is due to the complete flattening of the corrugated spring ring 36, although the temperature change gradually takes place, which, however, only a gradual increase in the exerted on the armature 32, magnetic force is connected.

As can be seen in Fig. 3, the movement of the armature 32, the liquid mercury through the narrow opening 34, bridging the upper part of the swimming chamber 16, is printed in the electrode chamber 20, in which the curved mercury surface conductively connects the electrodes 22. Should the switch be in a Angular position within 45 ° from the vertical attached the curved shape of the mercury mirror changes little because of the radius of curvature is only pivoted in a plane coinciding with gravity.

When the temperature changes in the opposite direction, the magnetic force eventually becomes like that far reduced until the armature 32 is released and the corrugated spring ring 36 him under a Snap action returns to its floating position on the mercury 30, so that the circuit between the electrodes 22 is interrupted.

In addition, it should also be mentioned that the distance between the magnet 42 and the housing 10, as shown in FIG is, can be changed so that the switch can be adjusted to a desired switching stroke.

Claims (3)

Patent claims: 1. Magnetically operated mercury switch of small dimensions with two fixed contacts inside the upper chamber of the housing and with a displacement body, its central opening is designed as a connecting channel to the upper chamber, furthermore with an outside of the housing lying device which actuates the displacement body magnetically, characterized in that, that the diameter of the upper chamber and that of the connecting channel is so small that the surface of the mercury contained therein is strongly curved, while the lower chamber and the for a small stroke provided displacement. body have a relatively large diameter. 2. Switch according to claim 1, characterized in that that a spring in the lower chamber supports the buoyancy of the displacement body. 3. Switch according to claim 1 or 2, characterized in that the spring as a spring washer is formed, which is arranged below the displacement body in the mercury and one Snap motion generated when the tightening force on the displacement body changes sufficiently, so that the two fixed contacts suddenly through the strongly curved mercury surface connected or disconnected. Documents considered: German Patent No. 637 197; British Patent Nos. 492 802, 667 760; French Patent No. 774036; U.S. Patent Nos. 2,247,493, 2,385,887. 1 sheet of drawings