US1312244A - Automatic contbol device - Google Patents

Description

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AUTOMATIC CONTROL DEVICE. APPLICATION FILED MAR. 13, I918.

1,312,244. Patented Aug. 5,1919.

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0. L. FORTIER.

AUTOMATIC CONTROL DEVICE.

APPLICATION FILED MAR. I8. 1913.

Patent-ed Aug. 5, 1919.

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TIIE coLummA ILANIIGRAPH 20 WASHINGTON, n. c.

CHARLES L. FDRTIER, or MILWAUKEE, Wisconsin.

AUTOMATIC conrnon nnvrcn. I

To all whom it may concern: 1

Be it known that I, CHARLES L. Fon'rmn,

a citizen of the UnitedStates, residing at Milwaukee, in the county of Milwaukee and tate of Wisconsin, have invented certain new and useful Improvements in Automatic Control Devices, of which the following is a specification. y

This invention relates to that type of thermostatic and hygrostatic control devices which employ a movable leak port tube or nozzle to vent the pressure fluid from the controlled motor or device. Instruments of this character are set forth in Patent No. 1,162,170 granted to Carl F. Johnson and dated November 30, 1915. 1

3y later improvements made by said Carl F. Johnson, a wider range of movement of the leak port tube or nozzle" has been rendered practicable, and this is quite desirable for many uses of the control mechanism; Such mechanisms, however, usually employ a bimetallic bar to respond to the atmospheric changes, and to carry the valvepad or closure which seals and unseals the leak port and initiates the action of the control mechanism. The radius of the bimetallic element is made relatively short in order to keep the mechanism within comparatively and the valve pad hence does not, in all adjustments of the instru-V small dimensions,

ment, seat squarely against the enclor perpendicular to the axis of the leak port tube or nozzle, and hence may not always seal said port completely. This is particularly true when the instrumentiis adjusted to afford a relatively wide range of movement of the leak port tube or nozzle and of the pad or valve-carrier.

The object of the present invention is to provide means for insuring the proper seatingof the valve on the leak port member, in

both the out and in ositions of said member, and thus to enable the instrument to work efliciently and certainly over a considerable and variable range of temperature,

This result I attain, preferably, by mounting the sealing valve upon theleak port tube or nozzle so astomove bodilytherewith, and causing the thermostat orvother fiecification of Letters Patent. Application filedltfarcli 18, 1918,

Serial 110,223,153. 1

element responsive to atmospheric condi-Y tions toact uponsaid sealing valve through intermediate devices, so that the valve may always seat squarely and perfectly, unaf fected in this regard by varying angularity of the actuating lever or element, or by vary ing range of movement thereof. e

I here illustrate theinventionas applied to the control of temperature, and in an instrument of thegeneral character set forth in Letters Patent No. 1,109,913 dated Sep tember 8, 1914, or No, 1,212,042 dated January 9, 1917, both granted to me. In the chosen illustration, however, I show of thermostat suitable for insertion vapor, and of the direct expansion type,

though my improvements are applicable in connection with various types of thermostats and hygrostats; so, too, the pad, valve, or closure may in some cases be car Patented Aug. 5,

a form lnto a tank or chamber containingllquichgas, or

ried by a lever pivotally supported upon the fixed frame ofthe instrument, together with p the adjusting devices for said lever,

Referring now to the accompanying draw lugs: i e

Figure l is a side elevationof a thermostatic control device embodying my ind provements;

Fig. 2 1s a frontelevation thereof,

Fig. 3 is asimilar view with parts broken away or in section to show parts that would otherwise be hidden;

Fig. 4f isja sectional view of theleakport tube or nozzle, the motor by which it is advanced and receded, and thevalve or closure which seals and unseals the leak port in response to changing atmospheric conditions,

the parts being shown in sealing position;

Fig. 5 is a similar View but with the parts i in unsealing relation;

Fig. 6 is a front face View of the same parts, showing the adjusting disk or head of the stop with its scale and pointer;

Fig. 7 is a view similar to F ig; 2, but showing the lever or arm carrying the sealing valve or closure for the leak port, otedlto the frame of the thermostat.

The construction and operation of thedevice may be best explained with thesaid of Fig. 3, wherein 1 indicates a tube of brass, copper, orother substance having a relatively high coefficient of expansion, and 2 a rod of some substance having a lower coefficient of expansion. The rear or inner end oftube l is closed by a cap 3, and the corresponding end of rod 2 is held in contact with its cap or closure by a spring 4:, bearing at its inner endagainst the radial flange of a cap sleeve 2 applied to the outer end of rod 2, and at its outer end against the inner wall of a combined cap-plate and bracket 12 secured to the frontofthe main frame, base or support 5 of the structure. The base or support 5 is formed with a tubular rearward extension-5 which receivesor forms a pipe head for the tube 1', saidextension being exteIiOrly threaded at its end to screw into thewall of a tank or vessel, and provided with a polygonal portion to receive a wrench or like toolfor' screwing it to place.

As shown in Fig.- 2, base or support 5 is formed with internally threaded bosses 7 and 8to receive pipes, the former being connected to an accumulator or pressurefluid supply, and the latter to a valve or device tobe controlled, as in the apparatus of the well-known Johnson system of temperature control. 6 indicates a casting which is secured by screws9 and 10-or other fastenings to the base 5, an air-tight joint between them'being insured by interposing a gasket 11 of leather, rubber, or other suitable material. j(See Fig. 3). p

-Hin'g'e'd or pivoted tobracket 12 is an upstanding lever 13, here shown as bifurcated .atv its lower end to, give it a broad hearing or support, and having one arm extended down below its pivot axis to bear against a spring 15, which tends to throw inward the upper end of the lever. Threaded or screwed through lever 13 a short distance above its pivot. axis, is an adjusting screw 14 which is held in contact with the outer end of rod 2orwith its cap sleeve 2 by the pressure of spring 15 urging lever 13 in-' :therewith.-.: To afford a broad bearing for the lever 19Yagainstthe diaphragm 17, its arms carry at their lower ends a disk or head 19 of circular outline, the bearing face of-whi'ch is made convex as is usual in such instruments. Contact of the convex disk 19 with the diaphragm is maintained by a spring 21 interposed between casting 6 and the upper end of lever 19, said spring being placed under compression. Its ends are seated in sockets or depressions in frame 5 and lever 19 to insure its retention in place.

The three-Way valve 16 is of the quick throw or snap action type, and is actuated by vibration of frame or lever 19, which carries at its upper end a confined. coil spring 28, which riding over a spherical head 29 of the valve stem and being thereby expanded on passing the center of the spherical head of the valve stem, suddenly contracts and expels said head 29, moving it sharply away from the annular spring in a direction opposite to that in which the lever moves. This and equivalent quick throw devices are illustrated and described in my prior patents above noted, and require no further explanation here. So, too, the function and mode of'operation of the threeway valve 16 being well understood and fully set forth in Patent No. 924.235 to Warren S. Johnson, need not be described at any length. The throw or play of frame or lever 19 is limited by a stop-serew 22. shown in Fig. 2, but omitted in other figures to avoid confusion. 9

Figs. 4 and.5 show that portion of the structure which embodies my invention. It consists of a chamber formed by two circular members 30 and 31. each having a circumferential flange, the two flanges being threaded and screwed together to form a closed air chamber to which air is admitted through a port or passage 32 connnunicating with thecentral air passage 27 of casting 6. which passage also communicates with the chamber containing diaphragm 17. The member 30 is provided with a threaded neck or nipple by which it is screwed into a correspondingly threaded socket in the casting 6 in the position indicated in Figs. 1, 2 and 3. Between the radial face of the flange of member 30 and an annular shoulder of the flange of member 31, is clamped a flexible diaphragm 34, which when not opposed by superior force is bowed or urged inward or toward the airport 32 by a light spring 35. or by its own resilience if the diaphragm be made of resilient material.

36 indicates a leak port tube the inner end of which is provided with a lixcd flange or collar 37 and a nut 38 which screws upon the rear end of the tube 37, to clamp and bind between it and the collar 37 the diaphragm 3-1, said diaphragm having a central opening to receive the leak port tube. The joint or connection between the leak port tube-and the diaphragm is, by the construction described, made air-tight. The tube 31) is longitudinally movable through a thread ed housing or nipple 39. screwed centrally into the cap member 31 of the diaphragm chamber. The housing or nipple 39 is provided at its forward or outer end with a circular disk, the circumference of which maybe milled to facilitate its turning to adjust it with reference to the chamber 3031. If preferred, holes will be drilled in the face of the disk to receive a pin by which to turn it. The face of said disk is graduated at its outer edge, the graduations being read in connection with a stationary pointer 40 carried by cap member 31 or other convenient support. The function of the housing or nipple 39 is primarily to con' stitute a stop to limit the outward movement of the leak port tube 36, its inner end being in the path of and arresting the collar 37 of said leak port tube. The inward movement is limited by the wall of member 30, which as shown has a raised central boss grooved to prevent-sealing of the leak tube.

When pressure fluid is admitted to the chamber 30-31 and the leak port tube is sealed, pressure is exerted upon the diaphragm 34 sufficient to overcome the resistance of spring 35, and to move the diaphragm and withit the leak tube 36. forward or outward. When, however, the leak port is unsealed, air escapes through said leak port to the atmosphere, permitting the spring 35 to collapse or how inward the diaphragm, and to cause a backward or rear ward movement of the leak port tube.

The cap member 31 is provided with a vent 41 to the atmosphere, to permit free movement of the diaphragm and leak port tube. 1 l

Carried by the leak port tube 36 is a bracket 42 to which is pivoted, or from which is suspended, a lever or bar 43 carrying a sealing disk or pad 44, preferably of patent leather, celluloid, or like material, which faces the end of leak port tube 36 and serves when; pressed against the end of said tube, to seal the leak port therein. A light spring 45 carried by the bracket 42 bears against the bar or lever 43, and tends to pressand hold the valve disk or pad in sealing contact with the leak port tube.

The operation of the device is as follows, reference being had to Figs. 3, 4 and 5:

Air or other pressure fluid enters at 7, passestothe three-wayvalve 16 by way of passage 24, and by way of passage 25 to restricted passage 26, through said passage.

26 to the main passage 27, and by the latter passage to the chamber containing diaphragm 17. By a passage-23 opening out of the main passage 27 and communicating with port 32 (Figs. 4. and 5), air also enters the chamber containing diaphragm 34. l:he leak port of tube 36 is of greatercapaclty than the restricted passage 26, hence when open permits air to waste or escape more rapidly than it can be supplied to the chamberscontaining diaphragms 17 and 34, and

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shown in Figs. 3 and 5, and the valve or device to becontrolled and which is piped to the three-way valve chamber at 8, will remain open. Upon a riseo-f temperature in the medium surrounding tube 1 (Figs. 1 and 3), said tube lengthens, and as rod2 expands or lengthens more slowly, it will be forced back into the tube by. spring 4, screw 14 following and continuing to bear upon the outer end of rod 2 or its cap sleeve by reason of the action of spring 15 upon the short arm of lever 13, the free upper end of which latter likewise moves inward.

As best shown in Figs. 3 and 5, the upper end of lever 13, which is brought to the form of a point or knife edge, stands directly in rear of and bears against the inner or rear face of bar 43 which carries the port-sealing valve disk orpad 44, and so long as the temperature remains between the normal or mid-point and a predetermined maxii'mun, holds said bar 43 slightly away from the outer end of the leak port tube 36 against the pressure of spring 45. When, however, by reason of expansion of the tube 1, occa sioned by rise of temperature, the free end oflever 13 moves inward, bar 43 with its valve disk or pad 44 will follow under the force of spring 45, until the pad or disk rests against the end of the leak port tube and seals the port. "When this occurs pressure will build up in the chambers containing diaphragms 17 and 34, and diaphragms 17, acting through lever or frame 19 and moving its upper endinward, will cause a quickthrow of the three-way valve 16 to position to cut off the supply of pressure fluid to the valve which iscontrolled by the instrument and supplied by the pipe connecting with boss 8. Diaphragm 34 will continue to move until collar 37 of the leak port tube encounters the inner end of nipple 39, by which time the bar or lever 43 will be carried forward clear of the upper end of lever13, leaving a gap as seen in Fig. 4.

Upon a fall of temperature from the pre determined maximum, contraction of tube 1 will force rod 2 longitudinally outward, and by reason. of its forward end bearing against screw 14 of lever 13, will cause the free. upper end of said lever to move also. Lever 13 must, however, move across the gap between its free end and bar or lever 43 {before it can act to unseat or move away the valve or disk 44 from the leak portof tube 36. The width or extent of this gap is regulated by adjustment of the nipple 39, andmaybe made greater or less according to the range of temperature desired between the opening and closing points. When the leak port tube is moved outward the dis-' tance predetermined by, adjustment of the nipple, be that distance greater or less, the unsealing will occur, and reversal of action will follow promptly. Heretoforethermostats designed to work over a range of a' ing and unsealing of the leak port is insured by the sensitive thermostat element.

In Fig. 7 the leak port tube 36 is shown screwed into or carried by an upright bar 46 fulcrumed at its lower end in brackets 47 formed upon the casting 6, said bar being urged inward or toward frame 6 by a light spring 48. The upper end of the bar 46 encircles or straddles a threaded stem-49 projecting from the front of frame 6, and plays between an inner stop-nut 50 and a milled outer nut 51, which latter may be adjusted as desired to limit and determine the outward movement of bar 46, and consequently of leak port tube 36. A finger 52 carried by the bar 46 or other support and projecting in front of the outer face of nut 51 registers with graduations' on the face of said nut, and constitutes an adjusting scale similar to the circular disk and pointer 40 of the other figure. The valve disk or pad 44 is carried by a bar or lever 43*"-, fulcrumed in ears or brackets 53 formed upon the lever 13, and its free end is drawn toward the leak tube 36* by'a light spring 54. Said bar or lever 43 hence moves with bar or lever 46 and with leak port tube 36, and maintains 'a fixed relation thereto except for the outward movement occasioned by lever 13, and the counter movement produced by spring 54. There will hence be no change in angular relation of the valve disk or pad 44 to the leak port nipple and port, and the pad will always seat squarely and perpendicular to the axis of the leak 'port' tube.

Adjusting screw 14' carries a radial arm 55 which moves over a graduated plate or scale 56 so that the screw may be accurately adjusted to determine the initial position of lever 13 relative to the bar or lever carrying the port-sealing pad or closure.

lVhile I have herein shown and described flexible diaphragms for the several fluid pressure motors, it is of course to be understood that the invention contemplates the use ofpistons, these being recognized in the art. as the equivalent of diaphragms, and.

used interchangeablytherewith. The claims are hence to be read with this understanding.

Other variations in the manner of mounting the valve or pad-carrying bar or lever will readily suggest themselves to the skilled mechanic, and are within the purview or scope of this invention, -whicl1 consists broadly in so mounting the valve or padcarrying element as that it shall move with the leak port tube or member, and hence be unaffected as to its relation. by the movements of said leak port tube.

Having thus described my invention what I claim is 1. In a control device of the leak port type, the combination with a movable leak port member of a closure for said port responsive to atmospheric conditions and bodily movable with said leak port member. v

2. A control apparatus of the character described, comprising a movable leak port member; stops limiting and determining the range of movement of said member; and a closure for the leak port responsive to atmospheric conditions and bodily movable with the leak port member.

3. A control apparatus of the character described, comprising a movable leak port member; an adjustable stop for limiting the outward moven'ient of said member; and a closure for the leak port responsive to atmospheric conditions and bodily movable with the leak port member.

4. A control instrument of the character described, comprising a leak port member; a bracket attached to and movable therewith; a bar or lever pivotally attached to said bracket and having a pad or disk facing the port of the member; and a spring tending to move the valve disk or pad toward the port of said leak port member.

A control instrument of the character described, comprising, in combination, a leak port tube or member bodily movable; an adjustable stop to limit and determine the range of movement of said member; a bracket mounted upon and movable with said member; a bar or lever pivotally attached to said bracket and provided with a disk or pad adapted to seal the port of said leak port tube or member; and a spring extending from the bracket to the pad-carrying bar or lever, and tending to press the latter toward the port of the leak tube or member.

6.'The herein described control instrument, comprising a body or base provided with supply and delivery ports and with a quick-throw valve; a leak port tube connected with and movable by a diaphragm subject to fluid pressure; a bracket connected with and movable by said leak port tube; a lever carried by said bracket and provided with a valve or pad adapted to close the port in said leak tube; a lever fulcrumed upon the main frame or base of the instrument and adapted to engage by its free end and to actuate the Valve or pad-carrying lever; a spring tending to move the actuating lever away from the pad or valvecarrying lever; and a member responsive to atmospheric changes, serving to move the proximity to said graduations; and a 010- aetuating lever in opposition to said spring. sure for the leak port bodily movable with 7. A control instrument of the character the leak port member. 10 described, comprising a movable leak port In testimony whereof I have signed my 5 member; a stop limiting and determining name to this specification.

the outward movement of said member and provided with graduations; a pointer in CHARLES L. FORTIER.

Eopies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents Washington, D. G,

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