US1473962A - Thermostatic circuit closer - Google Patents

Description

Wmv 13 9 M3923a THERMOSTATIC CIRCUIT CLOSER Filati A'Lg. 21 1922 Patented Nov. 13, 1923.

PATENT OFFICE.

IYICCORIVIIXCKl C. MPHERSON, OF HAMMOND, INDIANA.

THRMOSTATIC CIRCUIT CLOSER.

Application filed August 12, 1922. Serial No. 581,448.

To all 'whom t may coa-cem.:

Bel it known that MCCORMACK C. Mo- PI-rnnsoN, citizen of the United States, residincr at Hammond, in the `county of Lake and @tate of Indiana,'has invented certain new and' useful 'Improvements in Thermostati'c Circuit Closers, of which the following is a specification.

.The present invention relates to frost alarms adaptedA particularly for giving warning of a dropping in temperature in orchards, and the like, where a freezing or low temperature isv harmful andrundesirable. V Y An object Aof the present invention is to provide' a device which is thermostatically controlled to close a circuit when thetem` perature is reduced to a predetermined degree, or thereabouts, for the purpose, of

2Q operating a bell, a horn, or any 'suitable electrically controlled mechanism, for tale' mg action when such low temperature is attained. A Y y Various devices of this character have at `a predetermined low temperature so that they cannot be tampered with or changed as to the time of'operation;l which cannot be easily broken; which comprises but fewV parts so assembled as toproduce a device whichmay be suspended or placed ina desired'location where it may-be'susceptible to slight Vvariations ,in temperature and unfailingly operate when thetemperature falls to a predetermined degree.

A still further objectof the invention is toprovide a frost alarm ofthis character which has but one movable part and a pair of contacts,` the movable part` and contacts being all sealed and enclosedfifn such manner thatl accessthereto cannot-fbehad, and conhereto.

heretofore been patented and commerciallyv parts housed, sealed and fixed for operation sequently the fixed relation or adjustment of these parts cannot be accidentally or willfully changed.

With the foregoing and other `objects in view theinvention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended In the drawings, wherein like symbols refer to like or corresponding parts throughout theseveral views.' l A.

Figure 1 is a perspective view of a frost alarm constructed accordingto the present invention and in one position of use.

Figure 2 is a face view of the device.

[Figure 3 is a vertical cross section through the device taken substantially on the line 3-3 of Figure 2. 'Y

Figure 4 is a detail perspective view Vshowing a portion of the thermometer tube with one of the contacts blown therein, the section being taken substantially on the line 4 4 of Figure 2.

In the drawings, 10 designates a panel board of any suitable size and configuration for supporting and housing the various parts of the device, the panel board being shown as of rectangular oblong construction in the present instance.

yA thermometer vtube 11, having at its lower end the usual bulb 12 and' provided at its upper end with a second bulb 13, is

mounted on the' panel board 10 and is adapted to extend upwardly at a sufficient inclination to the horizontal toobtain the desired action and at the same time to position the tube 11 substantially longitudi@ tion and the bulb 12 constitutes the lower termination of the tube. lThe tube 11 is held in the groove 14 by straps 15 which engage across the outer side of the tube and which are screwed or otherwise suitably secured to the panel board 10 to hold the ther'inom'- eter tube 11 irn'ily in its seat in the panel board. Such construct-ion prevents vibration of the tube so that when the panel board receives jars, falls to the ground, and the like there is little likelihood of the tube 11 becoming damaged.

The bulb 1Q is protected by a plate which is secured across the lower end oi the groove 1st and over the bulbi 1Q to ward otl impact of surrounding object with the bulb and thus prevent accidental breakage of the same. The plate 12 is preferably slotted or otherwise perforated to admit 'tree access o t air to the bulb 1Q.

The body portion of the tube 11 also protected and housed by means of a sheath plate or protector 17 which is et sutleient width to overlap the groove 11 and Awhich is laterally enlarged opposite ends to receive attaching screws 18, or the like. for securing the plate i7 to the tace ot the panel board 10 and enclose the tube 11. The body portion of the tube 11 may be thus completely enclosed `lfrom view and trom access by external objects tor the complete protection oit the tube because the present dovice not adapted Yjor adjustment or Yfor taking readings, and the parts thereo't are so arranged that thcj.Y cannot be tamj'iered Wit-h and easily broken; thus producing a practical tool proof device which cannot easily get out ot' order.

The tube 11 is adapted to contain a rela tively short column of mecury 19, or other suitable electric conducting substance which is arranged intermediately of the body portion of the tube 11 and supported in the tube at opposite ends by columns 2() and 21 ot' the creosote or alcohol, or other suitably electricity non-conducting substance Which is readily susceptible to expansion and contraction under the influe-nee of temperature changes.

Blown or otherwise suitably positioned in the tube 11 are fixed contacts 22 and 23 which project into the cavity of the tube in rthe path of movement of the column of mercury 19, and which are spaced aipart a distance which permits Asimultaneous contact with the mercury only when the latter is permitted to move down in the tube 1l to the desired extent. These contacts 22 and 23 are so lo ated that when a temperature of approximately 34; degrees is reaclied the column of mercury 19 bridges the contacts, and thus closes any electrical circuit in Which the contacts may be included. It will be noted that the contacts extend 'trom an inner side of the tube 11, and constitute terminals of wires 24 Which are seated in grooves 25 formed in the rear tace of the panel board 10. The ivires 24 are secured to the inner ends of binding posts 526 which project through the ,forward tace ot the panel board 10, at their inner ends but which are seated in suitable recesses 2T at the inner side ot' the panel board. The grooves and recesses 27 at the inner side ot the panel board may be closed and by suitable covering` or layer 28 Which is cemented or otherwise secured in position to prei/'ent access to the parts so that such parte cannot be easily bro-ken or disconnected. The outer ends of the binding posts i6 provide terminals for electric Wires 29 which lead from a source of electrical energy and to any suit-able mechanism as may be de'red when a loiv temperature approaching the freezing point is reached.

The device is particularly adapted 'l'or use in orchards to protect the trees and fruit from injury from frost, and the device is adapted to be suspended or otherwise placed in an exposed position so that When cold `Winds or air strike the device it will respond, close the electric circ-uit and thus operate as desired to protect the fruit.

The panel board 10 may be equipped with a hanger 30 ofany suitable construct-nm., and shown in the present instance as in the form o'l a plate with an inverted key hold slot 31 therein through which a headed nail or the like may be engaged Jfor holding the panel board upon a post, tree, 'tence or the like7 and the plate 30 may be connected to the panel board by a pivot 32 permitting the swinging oit the plate 30 downwardly against the rear side of the board out of the Way for convenience in storing and shipping.

It obvious that various changes and modificationsmay be made in the details ol construction and design ot the above specifically -described embodiment ol this invention Without departing from the spirit thereof, such changes and modilications being restricted only by the scope o'l the lollowing claims.

lVhat is claimed is:

A thermostatic circuit closer comprising a. panel board having an upwardly inclined groove in its outer face extending in a general horizontal direction, a thermometer tube seated in the groove substantially flush with the outer face of the panel board and with its bulb in the lower end thereof, protecting means secured to the outer' tace ot' the panel board over the bulb and the tube for housing the same, lixed contacts blown into the lower side of the tube and. projecting into the adjacent Wall of the groove ot the panel board, a. non-conducting column of liquid in the lower end ot said tube, a column ot mercury arranged in the tube, above said non-conducting liquid for bridging said contacts when a predetermined low temperature reached, said panel board having channels `therein leading downwardly from said contacts, Wires extending from the contacts downwardly through said channels, to Ipermit connection of the wires to the blinding posts mounted on the outer face of binding posts, and 'a covering plate secured the panel board and terminating lat their `over the rear face of said panel board for 1 inner ends in the lower ends of said chanhou-sing in the wires and `the inner ends of 5 nels and Connected to said wires, the lower the binding posts.

end portions of said channels opening In testimony whereof I ax my signature.

through the rear face of the panel board MCCORMACK C. MCPHERSON.

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