US3153715A

US3153715A - Switch having variable differential and range adjustment

Info

Publication number: US3153715A
Application number: US213527A
Authority: US
Inventors: Charles F Weisgerber
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-07-30
Filing date: 1962-07-30
Publication date: 1964-10-20
Anticipated expiration: 1981-10-20

Description

Oct. 20, 1964 C. F. WEISGERBER Original Filed July .20. 1959 FIG. 1.

2 Sheets-Sheet 1 Fla. 4-. z 5

A x I I. v )I J; 9\ /2 I l w 35' INVENTOR. G- CHARLES Fwsazug-R anvr 20, 1964 c. F. WEISGERBER 3,153,715

SWITCH HAVING VARIABLE DIFFERENTIAL AND RANGE ADJUSTMENT Original Filed July 20, 1959 2 Sheets-Sheet 2 INVENTOR. CHARLES .E WEI-SGERBER United States Patent Ofiice 3,153,715 Patented Oct. 20, 1964 3,153,715 SWITCH HAVING VARIABLE DIFFERENTIAL AND RANGE ADJUSTMENT Charles F. Weisgerber, Whittier, Calif.

'(P.O. Box 1489, Wickenburg, Ariz.) Continuation of application Ser. No. 828,131, July 20, 1959. This application July 30, 1962, Ser. No. 213,527 7 Claims. (Cl. 200-170) This invention relates to a switch having variable differential and range and is particularly concerned with the control of an electrical circuit, or the like, by means of fluid pressures and throughout wide variables in both ditierential and range pressures and whereby accurate sensing of certain determined fluid pressures is usable to operate other devices as circumstances require, it being a general object of this invention to provide a practical and reliable switch that can be manually adjusted and which is accurate in the sensing, for example, of fiuid pressures to which it is responsive.

This application is filed as a continuation of applica tion Serial No. 828,131 filed July 20, 1959, and now abandoned.

Fluid operated pressure control switches of the type under consideration have been used for numerous purposes and where it is desired to govern the action of other devices in response to a fluid pressure. The ordinary control switches in which incremental movements are achieved are characterized by bellows or cylinder and piston actuated mechanical linkages, said linkages being multiplying lever-type linkages. The common linkage in such control switches, such as the multiplying levers thereof, are not only costly but they become inoperative for practical purposes in a very short time due to wear and play in the multiplicity of parts involved. In other words, when wear occurs where a multiplicity of parts is involved in a mechanism of the type under consideration, as in a usual multiplying linkage, there is a build-up of error and/or a magnification thereof and to such an extent as to render the control switch practically inoperative and useless.

An object of this invention is to provide a switch that is direct in its movement and wherein play or movements resulting from inaccuracies or from wear are not detrimental to the accuracy thereof. With the switch that I provide both differential and range pressures are adjustably variable and incorporated in a mechanism characterized by straight lineal movement involving a minimum number of parts.

It is an object of this invention to provide a pressure operated switch that is'responsive to both high and low fluid pressures wherein the range of said high and low fluid pressures is adjustably set as desired and at any time either before or after or during operation of the switch.

It is also object of this invention to provide a pressure operated switch that is responsive to both high and low fluid pressures and wherein the differential of said high and low fluid pressures is adjustably set as desired and at any time either before or after or during operation of the switch.

Further, it is an object of this invention to provide a pressure operated switch that is independently responsive to both adjustably selected differential and range settings, as above referred to, and wherein each of said differential and range settings can be independently eflected without disturbing or affecting either one or the other.

Also, it is an object of this invention to provide a pressure operated switch of the character referred to that is infinitely variable and infinitely responsive, within its operational range, to both diflerential and range settings and pressures, respectively.

An object of this invention is to provide a relatively simple and rugged control switch having the features thus far referred to and which is also inexpensive of manufacture and inherently long lived.

The various objects and features of my invention will be fully understood from the following detailed description thereof, throughout which description reference is made to the accompanying drawings, in which:

FIG. 1 is a side elevation of a pressure operated switch involving the embodiments of the present invention. FIG. 2 is a front elevation of the switch shown in FIG. 1 and taken as indicated by line 22 on FIG. 1. FIG. 3 is an enlarged detailed longitudinal sectional view taken substantially as indicated by line 3-3 on FIG. 2. FIG. 4 is a transverse sectional view taken as indicated by line 44 on FIG. 3, and FIG. 5 is a detailed sectional view of a portion of the switch and taken as indicated by line 5-5 on FIG. 4.

The control switch of the present invention is preferably an electrical control switch involving two or more spaced contacts that are movably and adjustably related to each other. The switch is fluid operated or responsive to fluid under pressure, either gas or liquid, and is operated by fluctuations in said fluid pressures. It will be apparent that the means responsive to pressure of fluid and adapted to shift a movable element can vary widely and, therefore, it is contemplated that any suitable means, such as, for example, a cylinder and piston unit, or a Bourdon tube can be employed as desired. It is to be understood, however, and in accordance with the broader principles of the present invention, that when I refer to pressure I not only mean fluid or liquid or gas pressure, but I also mean to include any and all other pressures including mechanical and electrical pressures. Therefore, the means responsive to pressure can be in the form of a mechanical bi-metallic thermostat mechanism or the like, or it can be in the form of an electrical or voltage 0perated mechanism or the like. Further, it is to be understood that the switch can be other than an electrical switch, such as, for example, a mechanical tripping device or sear, or, for example, a hydraulic latching device.

In FIGS. 1 and 2 of the drawings I have illustrated a typical embodiment of the control switch and which is diaphragm operated by fluid pressure to open and close an electrical circuit or circuits. A control switch, such as illustrated, can be employed, for example, for the control of gases or air, as in a furnace exhaust, or for missing and/or control of air of various percentages, or of various temperatures and densities, or simply for the control of gas or liquid pressures in a flow line, or for controlling any electrical circuit, as circumstances require. As shown, the switch X is cooperatively related to a pressure responsive means Y that is coupled to a pressure supply Z. The particular switch X illustrated is an electrical switch involving a plurality of

contacts

10, 11, 12 and 13. The particular pressure responsive means Y illustrated is a fluid pressure responsive diaphragm and the particular pressure supply Z illustrated is a duct in communication with a source of fluid under pressure, for example, air under pressure, and said air pressure being subject to fluctuations in pressure.

In accordance with the invention the pressure responsive means Y is directly connected to the switch element of the switch X, namely, the contacts 11 and 13, and the means Y or diaphragm involves a body 15 with a wall 16 defining a chamber 17 that is in open communication with the pressure supply Z. The body 15 supports a flexible and pressure sensitive membrane .18 that closes the chamber 17 and which membrane carries a contact mounting 19. In the particular case illustrated, the contact mounting 19 is grounded to the membrane, in which case the membrane is made of conductive material or incorporates a ground to the body 15. In the preferred form, the mounting 19 is an upstanding part that projects from the membrane 18 and which has a transversely extending member 20 that is in a plane normal to the axis of movement of said diaphragm membrane 18. More specifically, the member 20 is a flat metallic plate with the side facing away from the membrane forming the contact 13. It will be apparent that pressure of fluid upon the membrane 18 will move and position said membrane with consequent positioning of the member 20 presenting the contacts 11 and 13.

The switch X involves, generally, a housing A, guide means B, relatively movable contact carriages C and D, a shiftable support E, a carriage adjustment means F, and a support adjustment means G. The said elements of the invention, A through G, are constructed along the ex tended axis, or axis of movement, of the diaphragm membrane 18, the housing A being provided to support and enclose the other elements. The guide means B is supported within the housing A and is provided to shiftably carry the carriages C and D and also the support E. The carriages C and D are contact supporting elements that are adjustably positioned along the axis of the structure and are provided for differential adjustment of the switch X. The support E carries or positions the carriage adjustment means F that is provided for adjustably positioning the carriages relative to each other, and the support adjustment means G is provided for adjustably positioning the said support E for range adjustment of the switch X.

The housing A that encloses the elements of the switch X is a frame structure adapted to be suitably mounted or installed as required and involves a case that supports and encloses the other elements and a mounting for the case. The case 25 can be an open framework but is preferably a closed case having a cylindrical wall with access openings 26 as shown. The openings 26 can be closed by a cover 27 engaged over the case and the

ends

28 and 29 of the case are flat and normal to the central longitudinal axis thereof. A breather opening 27' can be provided as required. In accordance with the particular form of invention illustrated, the end 28 is an open end and is provided with a coupling flange 31 connected to the body 15 of the diaphragm, while the end 29 is a closed end and is provided with a bottom 32. The mounting 30 is shown engaged with and secured to the bottom 32 at the end 29 by means of fasteners 33, the mounting 30 being a plate-like element in the form of a dial 34 with indicia thereon calibrated for adjustment of the means G later described. In practice, the dial 34 is recessed in which case the mounting 30 is disc-shaped, said dial 34 being in a plane normal to the axis of the cylindrical case 25.

The guide means B that is supported in the housing A to carry the carriages D and C and the support E is provided to shiftably support the said carriages and the said support for movements longitudinally of the axis of the structure. The guide means B can vary in detail of construction but preferably involves a plurality of guideposts 35, preferably two spaced and parallel guideposts 35 that extend longitudinally of the case 25 and parallel with the longitudinal axis of said case. In practice, the two posts 35 are diametrically opposite the axis of the structure and they are carried by and project from the bottom 32 of the case where they are provided with shoulders having seated engagement with the case and threaded end portions receiving nuts securing the posts in working position. The said posts are smooth cylindrical ele ments coextensive with each other and which terminate at or about the end 28 of the case 25.

The contact carriages C and D are essentially alike and are provided for differentially positioning the

contacts

10 and 12 relative to each other, and each is shiftably supported by the guide means B and independently of each other. In practice, the carriages are in the form of flat plate-like bodies 36 and 46 with spaced parallel openings 37 and 47 that slidable pass the posts 35, respectively. The two bodies 36 and 46 are separated from each other longitudinally of the structure and are guided by the posts 35 to remain parallel with each other and they are characterized by

central bores

38 and 48 for cooperation with the adjustment means F later described.

In accordance with the invention, the carriage C and body 36 thereof supports and carries the contact 10 while the carriage D and body 46 thereof supports and carries the contact 12. The contacts are essentially alike, the contact 10 being such as to engage with the above described contact 11 that faces toward the diaphragm membrane 18, the contact 12 being such as to engage with the above described contact 13 that faces away from the diaphragm membrane 18.

The contact 10 involves a contact arm 50 carried by an insulator 51, said insulator 51 being secured to the carriage C, while the contact 12 involves a contact arm 60 carried by an insulator 61, said insulator 61 being secured to the carriage D. The insulators 51 and 61 project from their respective carriages and extend toward the membrane 18 and contact plate 20 carried thereby, and in a direction parallel with the longitudinal axis of the structure. In the case of the insulator 51 the longitudinal extent thereof is such as to place the contact arm 50 at or in the vicinity of the contact 11. In the case of the insulator 61 the longitudinal extent thereof is such as to place the contact arm at or in the vincinity of the contact 13. As clearly illustrated, the insulator 51 is a post-shaped part that simply projects from the body 36 of the carriage C while the insulator 61 is a post-shaped part that projects from the body 46 of the carriage D and by or through the body 36 of the first mentioned carriage C. In carrying out the invention, the said carriage C is provided with an aperture 52 (see FIG. 5) that freely passes the insulator 61 with substantial clearance.

The

contacts

10 and 12 involving the arms 50 and 60 are preferably spring contacts in which case the said arms 50 and 60 are resilient spring arms that are carried by the insulators 51 and 61 to be electrically isolated from each other. As shown, the insulators 51 and 61 are laterally olfset from the central axis of the structure and the spring arms 50 and 60 project inwardly, the arm 50 having a terminal end portion at the center of the struc' ture and forming the contact 10 and opposed to the contact 11, and the arm 60 having a terminal end portion at the center of the structure and forming the contact 12 and opposed to the contact 13. As shown, the plate 20 is also at the center of the structure intermediate the

contacts

10 and 12. It will be apparent that the spacing of the

contacts

10 and 12 from the contacts 11 and 13, respectively, will be determined by the positioning of the spaced carriages C and D.

In the preferred form, the two posts 35 are stabilized at their outer or free ends by means of a header 55 that engages with shoulders at the outer ends of said posts and which is secured thereto by means of nuts 56. With the header 55 provided, as shown, the insulators 51 and 61 project by or through the header 55, said header being provided with recesses or openings therethrough that freely pass the insulators 51 and 61 with substantial clearance (see FIG. 5).

The shiftable support E, that is provided to carry or position the carriages C and D through the carriage adjustment means F later described, is similar to the carriages C and D and is shiftably supported by the guide means B and independently of said other two carriages. In practice, the support E is in the form of a flat platelike body 66 with spaced parallel openings 67 that slidably pass the posts 35. The body 66 is guided by the posts 35 to occur intermediate the bottom 32 of the case 25 and the said carriages C and D, and it is characterized by a central bore 68 for cooperation with the adjustment means F later described.

The carriage adjustment means F that adjustably positions the carriages C and D relative to each other for differential placement or positioning of the contacts and 12 is, in accordance with the invention, a screw adjustment means that shifts either one or both of the carriages to position them, and the contacts carried thereby, in opposition to each other. That is, either the carriage C or the carriage D can be moved, the other remaining still relative to the support E. It is preferred, however, that the two carriages C and D be simultaneously moved in opposite directions upon actuation of the means F, either to move oppositely together or oppositely apart, as desired. As shown, the adjustment means F involves a stem 70 that is threadedly engaged in the

bores

38 and 48, respectively, the stem being rotatably journaled in the bore 68 provided in the support E and the stem being accessible at the dial for manual adjustment.

The stem 70 is a shaft-like element with an enlarged threaded portion 71 engaged in the bore 48 and with a reduced threaded portion 72 engaged in the bore 38. Further, the stem has a shoulder 73 engaged with and positioned by one side of the support body 66 and a collar 74 is secured thereto to engage with and be positioned by the other side of the support body 66. The threads at the

portions

71 and 72 can be differential threads of different pitch, or they can be of the same aiid opposite pitch as indicated, and to the end that the carriages move together or apart when the stem 70 is rotated. As is indicated, the dial 34 has an opening 75 freely passing the sleeve 80, said sleeve freely projecting through an opening 76 in the bot-tom 32 of the case 25.

The support adjustment means G that adjustably positions the support E for range placement or positioning of the

contacts

10 and 12, is, in accordance with the invention, a screw adjustment means that shifts the support B so that the carriages C and D are shifted in unison. As shown, the adjustment means G involves a sleeve 80 that is threadedly engaged with either the frame A or support E, and preferably threadedly engaged with the support, in which case it is rotatably journaled in the frame A and accessible at the dial 34 for manual adjustment. As shown, the sleeve 80 is coaxial with and is engaged over the stem 7 0 above referred to and the sleeve 80 is threaded onto a projecting portion of the body 66 of the support E. The stem has an enlarged internally threaded portion 81 that engages with the said threaded projection of the body 66, the remainder of the sleeve freely passing the stem 70. Further, the sleeve 80 has a shoulder 83 engaged with and positioned by one side of the bottom 32 and a collar 84 is secured thereover to engage with and be positioned by the other side of the bottom 32. It will be apparent that the support E is shifted longitudinally in one direction or the other depending upon the direction of rotation of the sleeve 80.

From the foregoing, and from a study of the drawings, it will be apparent that the structure disclosed can be readily assembled and that it is rugged and durable. In order to eliminate freedom of movement or play be tween the relatively movable carriages C and D, when they have been selectively positioner, I provide means to yieldingly urge said carriages oppositely. Preferably, I employ one or more simple compressed springs 90 intermediate the carriages and which act to press the carriages apart thereby applying pressure to the threaded engagement. Further, in order to eliminate freedom of movement or play between the case A and support E, once the support has been selectively positioned, I provide means to yieldingly urge said support in one direction. Preferably I employ one or more simple compression springs 91 intermediate the case A and support E to press them oppositely apart thereby applying pressure to the threaded engagement. It will be seen that the said springs maintain tightness and freedom from play, even though wear takes place at the pants involved.

In order to selectively position the

contacts

10 and 12 the means F and G are manually actuated, the sleeve being provided with a manually operable control knob 95 with a pointer. 96, and said stem 70 being'provided with an end configuration at 97 adapted to be engaged and operated bya tool, such as, for example, a screw driver or the like. A removable plug 98 is provided in the knob 95 to gain access to the stem 70 for operation thereof. Adjusting the switch both for differential and range can be easily accomplished through rotation of the coaxial adjusting stem and sleeve fromoutside-of the case. Not only is the adjustment of micrometer magnitude, but

can be set to control an infinite number of ranges and/or differentials of movement. Because of its ease of outside adjustment and low power requirements, it is possible to isolate or seal the structure within the case A in order to protect it from any contaminatiing outside atmosphere.

Having described only a typical preferred form-of my invention, I do not Wish to be limited or restricted to the specific details herein set forth but I wish to reserve to myself any variations or modifications that may appear to those skilled in the art and which fall within the scope of the following claims.

Having described my invention, 1 claim:

1. A control switch having separate differential adjustment and range adjustment, and including, a carrier movable longitudinally in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guide aligned with the longitudinal movement of the carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried by said guide, opposed switch contacts supported by each carriage respectively and opposed to said contact faces on the carrier respectively, a longitudinally movable supportshiftably carried by said guide, differential adjustment means carried by the support and comprising a manually adjustable part engaged between and positioning the carriages longitudinally relative to each other, and range adjustment means comprising a manually adjustable part positioning the support longitudinally.

2. A control switch having separate differential adjustment and range adjustment, and including, a carrier movable longitudinally in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guide aligned with the longitudinal movement of the carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried by said guide, opposed switch contacts supported by. each carriage respectively and opposed to said contact faces on the carrier respectively, a longitudinally movable support shiftably carried by said guide, differential adjustment means carried by the support and comprising a manually rotatable part engaged between and positioning the carriages longitudinally relative to each other, and range adjustment means comprising a manually rotatable part positioning the support longitudinally.

3. A control switch having separate differential adjustment and range adjustment, and including, a housing, a carrier movable longitudinally relative to the housing in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guidepost carried in the housing in alignment with the longitudinal movement of the carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried on said guidepost, opposed switch contacts supported by each carriage respectively and opposed to said contact faces on the carrier respectively, a longitudinally movable support shiftably carried by said guidepost, differential adjustment means comprising a part operable from the exterior of the housing and carried by the support and engaged between the carriages to adjustably position the carriages longitudinally relative to each other and range adjustment means comprising a part operable from the exterior of the housing and engaged with and positioning the support longitudinally of the housing.

4. A control switch having separate differential adjustment and range adjustment, and including, a housing, a carrier movable longitudinally relative to the housing in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guidepost carried in the housing in alignment with the longitudinal movement of the carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried on said guidepost, opposed switch contacts supported by each carriage respectively and opposed to said contact faces on the carrier respectively, a longitudinally movable support shiftably carried by the guidepost, differential adjustment means comprising a part rotatable in the support and extending between and threadedly engaged 'in each carriage to position the carriages longitudinally relative to each other, and range adjustment means comprising a part rotatably supported in the housing and threadedly engaged in and positioning the support longitudinally of the housing.

5. A control switch having separate difierential adjustment and range adjustment, and including, a housing, a carrier movable longitudinally relative to the housing in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guide in alignment with the longitudinal movement of said carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried by said guide, opposed switch contacts supported by each carriage respectively and opposed to said opposite contact faces on the carrier respectively, a longitudinally movable support shiftably carried by said guide, differential adjustment means comprising a differentially threaded part rotatably carried by the support and extending between and threadedly engaged in the carriages and positioning the carriages longitudinally relative to each other, and range adjustment means comprising a part rotatably supported in the housing and threadedly engaged in and positioning the support longitudinally of the housing.

6. A control switch having separate differential adjustment and range adjustment, and including, a housing, a carrier movable longitudinally relative to the housing in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guidepost carried in the housing in alignment with the longitudinal movement of the carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried on said guidepost, opposed switch contacts supported by each carriage respectively and opposed to said contact faces on the carrier respectively, a longitudinally movable support shiftably carried by the guidepost, differential adjustment means operable from the exterior of the housing and comprising a part rotatable in the support and extending between and threadedly engaged in each carriage to position the carriages longitudinally relative to each other, and range adjustment means operable from the exterior of the housing and comprising a part rotatable in the housing and threadedly engaged in and positioning the support longitudinally of the housing.

7. A control switch having separate differential adjustment and range adjustment, and including, a housing, a carrier movable longitudinally relative to the housing in response to the application of pressure thereto, opposite contact faces on the carrier, a longitudinally disposed guide aligned with the longitudinal movement of the carrier, a pair of longitudinally spaced and relatively and independently movable carriages shiftably carried by said guide, opposed switch contacts supported by each carriage respectively and opposed to said opposite contact faces on the carrier respectively, a longitudinally movable support shiftably carried by said guide, difierential adjustment means operable from the exterior of the housing and comprising a differentially threaded part rotatably carried by the support and extending between and threadedly engaged in and positioning the carriages longitudinally relative to each other, and range adjustment means operable from the exterior of the housing and comprising a part rotatable in the housingand threadedly engaged in and positioning the support longitudinally of the housing.

Harrington Feb. 15, 1927 Judson Dec. 4, 1956

Claims

1. A CONTROL SWITCH HAVING SEPARATE DIFFERENTIAL ADJUSTMENT AND RANGE ADJUSTMENT, AND INCLUDING, A CARRIER MOVABLE LONGITUDINALLY IN RESPONSE TO THE APPLICATION OF PRESSURE THERETO, OPPOSITE CONTACT FACES ON THE CARRIER, A LONGITUDINALLY DISPOSED GUIDE ALIGNED WITH THE LONGITUDINAL MOVEMENT OF THE CARRIER, A PAIR OF LONGITUDINALLY SPACED AND RELATIVELY AND INDEPENDENTLY MOVABLE CARRIAGES SHIFTABLY CARRIED BY SAID GUIDE, OPPOSED SWITCH CONTACTS SUPPORTED BY EACH CARRIAGE RESPECTIVELY AND OPPOSED TO SAID CONTACT FACES ON THE CARRIER RESPECTIVELY, A LONGITUDINALLY MOVABLE SUPPORT SHIFTABLY CARRIED BY SAID GUIDE, DIFFERENTIAL ADJUSTMENT MEANS CARRIED BY THE SUPPORT AND COMPRISING A MANUALLY ADJUSTABLE PART ENGAGED BETWEEN AND POSITIONING THE CARRIAGES LONGITUDINALLY RELATIVE TO EACH OTHER, AND RANGE ADJUSTMENT MEANS COMPRISING A MANUALLY ADJUSTABLE PART POSITIONING THE SUPPORT LONGITUDINALLY.