US2451751A - Switch device - Google Patents

Description

Oct. 19, 1948 c. G. KRONMILYLVER SWITCH DEVICE Filed May 19, 1944 Patented Oct. 19,-1948 SWITCH DEVICE Carl G. Kronmiller, Minneapolis, Minn., assignmto Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a corporation of Delaware Application May 19, 1944, Serial No. 536,234

Claims. 1

This invention relates to a switching mecha= nlsm and more particularly to that type of switching mechanism wherein a mercury switch is utiiized to make or break a circuit to control suitable apparatus in response to variations in the value of a condition.

A principal object of this invention is the movision in a switching mechanism embodying a mercury switch of means whereby the mercury switch may be adjusted with respect to the switching mechanism.

It is a further object of this invention to mount the switching mechanism which includes a inercury switch in any position such as in a vertical or horizontal position and provide means for adjusting the mercury switch to the necessary position for proper operation.

It is a further object of this invention to provide a transparent plastic casing for enclosing an adjustable mercury switch whereby the adjusted positions of the mercury switch may be easily observed.

It is another object of this invention to mount a mercury switch in a housing whereby the mercury switch may e adjusted with respect to the said housing.

It is a still further object of the invention to provide a casing for a mercury switch and means by which the switch is maintained in a central position in the casing while being; adjustable in a rotary movement.

It is another object of this invention to provide a casing for housing a mercury switch and to provide means cooperating" with loosely mounted conductor plates for the mercury switch for preventing the conductor plates from rotating when the mercury switch is adjusted relative to the casing so that conductor wires leading from the conductor plates may not the twisted or disturbed.

It is another object of this invention to utilize a switching mechanism comprising a mercury switch adjustably housed in a casing, whereby the switching mechanism may be mounted at various angles and still operate properly.

These and other objects will readily become apparent as the following specification is read in the light of the accompanying drawings.

The mercury switch employed in the switching mechanism is the metal clad switch disclosed in Patent Number 2,342,354, issued February 22, 1944 to Raymond P. Mattern. The switching mechanism is adapted to be associated with an apparatus to be controlled such as a refrigeration system.

Figure 1 is a front elevaticnal view of the switching mechanism with the cover removed;

pmember of this invention.

Similar reference characters refer to similar parts throughout the several views of the drawinc.

Referring now specifically to the drawing, there is indicated at it a casing of a switch mechanism ii to the lower portion oi which is secured a housing it which contains a conventional Sylphon bellows, not shown. A suitable pressuife or capillary tube, not shown, may lead into the housing from any suitable source, not shown, the arrangement being such that a conditionchange adjacent the-said source causes expansion or contraction of the Sylphon bellows in a known manner to produce upward or downward movement of an operating rod it. 011 the other hand. the believe may be connected directly to a source of pressure. Operating rod it bears against a memher 66 carried icy one end of a lever it which is ful-crumed on a knife edge of a bracket it which is secured to the rear portion 26 of the casing ill. A spring 26, suitably secured to the lever 18,-hiases the lever in a clockwise direction so as to oppose movement of operating rod it when the rod it is actuated by a change in the condition. The spring may e adjusted as by a screw 253 in a lmown manner to vary the value of the condition which the mechanism will operate.

An angular upwardly extending rod St is appropriately secured to the lever is! and extends through an opening in the top of the instrument ill. There are two spaced plates 32, each having a flanged portion by which the said plates are secured to the outside top portion of the casing iii. A casing 855 is provided with shafts E56 and 38 for mounting the housing 68 in appropriate apertures in the spaced apart plates 32. A lini: St is pivoted at one end to the upwardly extending rod 3% and is appropriately secured at its other end to the switch housing 68.

Two metal cups AB and 42 form an envelope for a mercury switch 35. These two cups cooperate with a partition 44 which is composed of a high grade of lava or molded ceramic having sub stantlally the same characteristics as lava. The partition 44 is provided with a circumferential flange 46 which forms a pair of shoulders 48 and 50. The said cups All and 42 are seated respectively on the shoulders 50 and 48.

The cup 42 is provided with an open end which is of greater diameter than the cup 40 and which accuser.

extends over the flange st of the partition as and also telescopes over the open. end of the cup Oil. An asbestos washer as is placed against the shoulder 80, and the open end of the cup ltl seats against this washer. A ring of glass be is fused to the two metal cups and seals the angular space between the two cups in order to seal the interior of the switch from the external atmosphere.

The switch envelope is partially filled with some suitable electrically conducting fluid such as mercury as indicated at 80. The partition (it is provided with an opening indicated at 62 by means of which two pools oi mercury as and be may be connected when the opening 52 is in the position shown in Figure 3. The switch mechanism ii is actuated by a change in the condition at the source (not shown). This change in the condition actuates the bellows contained in the housing i2 which moves the operating rod i6, lever 36, uwardly extending rod as. and link thereby rotating the switch housing as and the mercury switch 35 which is spaced in the housing 88 so that the opening 82 of the switch is moved out of the mercury 80, at which time the partition 46 will divide the mercury into the two separate pools 63 and 84 and therefore break the circuit through the switch 85. When the value of the wet by the mercury, preferably nickel, and .therefore the resistance between the mercury and these contacts is relatively low.

The casing 68 for housing the mercury switch 36 is preferably formed of transparent plastic material, although other insulation materials may be employed. The plastic casing comprises two cup-like members 69 and ii, each having an enlarged portion at its open end provided with screw threads for securing the two cup members together in assembled relationship. The cuplike member ll of the plastic casing be is provided with an inner annular flange it against which a collector plate it is loosely mounted. The collector plate is provided with an opening in its central portion, for purposes which will be later noted. The switch is fitted into the cuplike member Ii so that the metal cup 62 of said switch abuts plate it. One end of a compression spring M is positioned against the closed end of the cuplike member 88 and the opposite end engages a collector plate 80. When members 69 and it of casing 68 are assembled together, the collector plate 80 will be held in abutting relationship with metal cup 40 of the switch 35 by spring 74 which also provides a means for positioning switch 35 in casing 68 by biasing the switch 35 and collector ring 18 against the flange i8. Spring 74 further biases the collector plates 80 and 76 into frictional engagement with switch 35 to provide for movement of the mercury switch with the casing 88. The central circumferential portion of the mercury switch is receivable in the enlarged portion of casing 68 for positioning the switch in the midsection of the casing. The annular flange E3 includes a lug portion 12 which fits into a recessed portion 18 of collector plate 18 prohibiting rotative movement oi. plate 18 with respect to casing as as will be later noted. A lug it formed in cuplilre member to of casing es extends into a recess 82 in collector plate 89 preventing the loosely mounted collector plate as from rotating with respect to casing cs. Conductors t4 and 88 lead from the loosely mounted collector plates as and it respectively and extend through openings in the casing cc and lead to a panel plate not shown.

The shaft 88 of the housing 6% is hollow whereby a tool such as a screw driver may be inserted through the hollow shaft 88 to engage a slot it in the plate 62 for adjusting the mercury switch 855 in relation to the casing as. When the mercury switch 85 is adjusted with respect to the plastic casing 68, the loosely mounted conductor collector plate so is prevented from rotating because the lug member it extends into the recess 82 of the plate member (is. The sides at the recessed portion la oi the collector plate i6 engaging the lug member 712 oi the plastic casing hi3 prevents the collector plate is from rotating with respect to the casing 68 when the mercury switch is adjusted by a tool. The mercury switch as may be adjusted when necessary, and since the collector plates t6 and it are not rotated, their conductors 66 and 8% are not twisted or disturbed and the operating characteristics of the mercury switch are maintained. The mercury switch as is provided with indicia to indicate when the mercury switch-is in its properly adjusted position in the plastic casing es, and the positioning of the mercury switch is easily discernible through the transparent plastic casing $38.

In providing a mercury switch which is housed in a casing member so that the mercury switch can be adjusted with respect to said plastic casing, it is possible when the mercury switch is used in combination with a switching mechanism as disclosed in Figure l for the switching mechanism ii to be mounted at difiterent angles such as vertical and horizontal angles on the apparatus to be controlled. That is, the switching mechanism ii may be mounted on the apparatus to be controlled at any desired angle or position, and the mercury switch 85 may be adiusted with respect to the casing so to the position necessary for proper operation.

As many embodiments may be made of the above described invention and as many modifications may be made in the embodiments above described, it is to be understood that all matter hereinbefore described or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In a switch device of the class described, a transparent casing, and a cylindrical mercury switch which is operative by rotation on its longitudinal cylindrical axis positioned within said casing, biasing means within said casing and abutting said mercury switch to cause said switch to move in unison with said casing in response to movement ofsaid casing, a tool receiving portion on said mercury switch to provide means for manual rotation of said switch independent of said casing, said casing having an aperture adjacent said tool receiving portion to provide access for insertion of a tool, the transparency of said casing providing for visual observation of the position oi said switch with respect to said casing during the period of manual rotation whereby said switch may be manually rotated to an operative position without respect to the position of said casing.

2. A control device, comprising, a supporting member, a condition responsive means mounted on said supporting member, an enclosed casing carried by said supporting member. a pair of spaced electrically conductive elements located on the interior of said casing, said casing and said elements being rotatable in respect to said supporting member, a connection between said condition responsive means and said casing for slightly rotating the same upon change in the value of the condition'to which said condition responsive means responds, a liquid contact switch having an operative position in which small movements thereof cause making and breaking of the circuit therethrough, said switch being mounted on said conductive elements and having two circuit completing conductive members one of which is in contact with each of said conductive elements, and means mechanically connecting said liquid contact switch to said conductive elements for rotation therewith, said switch having a tool receiving portion and said enclosing casing having an aperture therein adjacent said tool receiving portion for insertion of a manually operable tool to rotate said liquid contact switch through 360 degrees in respect to said conductive elements whereby said switch may be placed in its operative position for any position of said supporting member within a single plane of rotation.

13. In a device of the class described, an insulating casing, a liquid contact switch having operative positions from which small movements theremounted on said supporting member, an insulatof cause making or breaking of a circuit thereternal 01' said casing whereby said switch may be positioned in an operative position by manual ldiustment.

4. In a switch device of the class described, a

supporting member, a condition responsive means ing casing carried by said supporting member and mounted for movement relativ to said supporting member. a connection between said condition responsive, means and said casing for moving the same upon change in the value or the condition to which said condition responsive means retive position from which small movements therefrom cause making and breaking of a circuit therethrough. means mounting said switch within said casing to cause said switch to move in unison with said casing in response to movement of said casing, a tool engaging portion on said switch to provide means for manual rotation of said switch independent of said casing, said casing having a tool receiving aperture therein adjacent said tool engaging portion for insertion oi a manually operable tool to rotate said switch with respect to said casing whereby said switch may be placed in an operative position, and means for indicating the relative position of said switch within said casing.

6. In a switch device of the class described. an insulating casing, a liquid contact switch having operative positions from which small movements thereoi cause making or breaking of a circuit therethrough, means mounting said switch within said insulating casing and adapting it to normally move with said casing, and means for applying movement to said casing to operate said switch, said switch having a tool engaging means thereon by which said switch may be rotated independent of said casing, said casing having an aperture therein adjacent said tool engaging portion to provide for insertion of a tool.

CARL G, KRONMIILER.

anrnamwcas crrm The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,313,166 Nicholas liar. 9, 1943

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