Pressure-to-electric transducer

Claim 2

A transducer apparatus for providing an electrical output voltage linearly proportional to an input pressure comprising an expandable and collapsible pressure chamber having a fluid inlet means, a main lever pivotally supported adjacent said chamber, force transfer means for moving said main lever in one direction about its pivot in direct response to increases of pressure in said chamber, an elongated spring member disposed in space relation along said main lever having one end fixed at said pivot and the other end disposed in resilient engagement with said main lever to urge said main lever against said force transfer means, variable resistance means for providing an electrical output signal directly proportional to the movement of said main lever about its pivot and set point means for varying the transverse angle between said other end portion of said spring member and said main lever to selectively adjust the point at which the pressure will actuate said variable resistance means.

Claim 3

A transducer apparatus for providing an electrical output voltage linearly proportional to an input pressure comprising an expandable and collapsible pressure chamber having a fluid inlet means, a main lever pivotally supported adjacent said chamber, force transfer means for moving said main lever in one direction about its pivot in direct response to increases of pressure in said chamber, spring means biasing said lever against movement in said one direction, and variable resistance means for providing an electrical output signal directly proportional to the movement of said main lever about its pivot, said variable resistance means including an elongated resistive element, voltage input terminals electrically connected across said resistive element, a condUctive rocker member having an arcuate contact portion disposed lengthwise of said resistive element, voltage output terminals electrically connected between said rocker member and one of said voltage input terminals, and translational means operatively connected between said main lever and said rocker member to convert the arcuate motion of said main lever to a translational force which is directed against one end of said rocker member causing said contact portion to roll along said resistive element in direct proportion to the change in pressure in said pressure chamber.

Claim 4

A transducer apparatus for providing an electrical output voltage linearly proportional to an input pressure comprising an expandable and collapsible pressure chamber having a fluid inlet means, a main lever pivotally supported adjacent said chamber, force transfer means for moving said main lever in one direction about its pivot in direct response to increases of pressure in said chamber, spring means biasing said lever against movement in said one direction, and variable resistance means for providing an electrical output signal directly proportional to the movement of said main lever about its pivot, said variable resistance means including an elongated resistive element, voltage input terminals electrically connected across said resistive element, a condUctive rocker member having an arcuate contact portion disposed lengthwise of said resistive element, voltage output terminals electrically connected between said rocker member and one of said voltage input terminals, and translational means operatively connected between said main lever and said rocker member to convert the arcuate motion of said main lever to a translational force which is directed against one end of said rocker member causing said contact portion to roll along said resistive element in direct proportion to the change in pressure in said pressure chamber.

Claim 5

A transducer apparatus for providing an electrical output voltage linearly proportional to an input pressure comprising an expandable and collapsible pressure chamber having a fluid inlet means, a main lever pivotally supported adjacent said chamber, force transfer means for moving said main lever in one direction about its pivot in direct response to increases of pressure in said chamber, spring means biasing said lever against movement in said one direction, said spring means including an elongated member disposed in space relation along said main lever and having one end portion rigidly supported at said pivot and the other end portion extending beyond the point of contact of said force transfer means with said main lever, said other end portion having resilient characteristics and disposed in engaging relation with said main lever to urge said main lever against said force transfer means, and variable resistance means for providing an electrical output signal directly proportional to the movement of said main lever about its pivot.

Claim 6

A transducer apparatus for providing an electrical output voltage linearly proportional to an input pressure comprising an expandable and collapsible pressure chamber having a fluid inlet means, a main lever pivotally supported adjacent said chamber, force transfer means for moving said main lever in one direction about its pivot in direct response to increases of pressure in said chamber, spring means biasing said lever against movement in said one direction, said spring means including an elongated member disposed in space relation along said main lever and having one end portion rigidly supported at said pivot and the other end portion extending beyond the point of contact of said force transfer means with said main lever, said other end portion having resilient characteristics and disposed in engaging relation with said main lever to urge said main lever against said force transfer means, and variable resistance means for providing an electrical output signal directly proportional to the movement of said main lever about its pivot.

Claim 7

A transducer apparatus as defined in claim 3, further comprising a differential range adjust means for selectively varying the point of contact in a lengthwise direction between said resilient end portion of said elongated spring member and said main lever to thereby vary its effective spring rate.

Claim 8

A transducer apparatus as defined in claim 4, wherein said differential range adjust means comprises a block member slidably mounted on said main lever and having a spacer portion sandwiched between said outer end portion of said spring member and said main lever, and an adjustment screw rotatably mounted on said main lever in a lengthwise direction and in threaded engagement with a threaded bore in said block member.

Claim 9

A transducer apparatus as defined in claim 3, further comprising set point means for varying the transverse angle between said resilient end portion of said spring member and said main lever to selectively adjust the point at which the pressure will actuate said variable resistance means.

Claim 10

A transducer apparatus for providing an electrical output voltage linearly proportional to an input pressure comprising a frame having a bottom wall and a pair of sidewalls, an enclosed housing supported below said bottom wall and having a central passageway formed therethrough in alignment with an opening in said bottom wall, a cavity formed within said housing intersecting said central passageway, a diaphragm member disposed across said cavity crosswise to said central passageway to define an expandable and collapsible pressure chamber with the lower portion of said cavity, a force transfer member slidably supported in the upper portion of said central passageway with its lower end abutting against said diaphragm member and its upper end extending above said bottom wall, a pivot member extending between said sidewalls above and to one side of said force transfer member, a main lever extending lengthwise between said sidewalls and supported between said pivot member and the upper end of said force transfer member, spring means biasing said lever towards said force transfer member, and variable resistance means for providing an electrical output signal directly proportional to the movement of said main lever above said pivot member caused by the displacement of said force transfer member in response to changes in the pressure of said pressure chamber. 8. A transducer apparatus as defined in claim 7, wherein said variable resistance means comprises an elongated housing mounted between said side walls above said main lever, said elongated housing having an enclosed elongated cavity, three terminal members projecting above the upper surface and extending through three spaced passageways in said elongated housing between said cavity and said upper surface, a flat resistive element electrically connected to two of said terminal members in said cavity and having a resistive coating facing downwardly, a conductive rocker member having an arcuate contact portion disposed in rolling relation with said resistive coating, the third of said terminal members electrically connected to said conductive rocker member, a plunger element slidably disposed through a sleeve provided crosswise through the bottom wall of said elongated housing, the upper end of said plunger element in engaging relation with one end of said rocker member and its lower end operatively connected with said main lever such that the arcuate motion of said main lever about said pivot member causes a translational movement of said plunger element, and second spring means for biasing said rocker member to follow the translational movements of said plunger element.

Claim 11

A transducer apparatus as defined in claim 8, further comprising a range select panel which snaps over the upper ends of said three terminal members, said range select panel including a printed circuit board with openings to fit over said three terminal members, three terminal posts extending upwardly from the upper surface of said circuit board, first and second resistors, first and second conductive means for electrically connecting, respectively, said first and second resistors between first and second of said three terminal posts and said two of said terminal members, and third conductive means for electrically connecting the third terminal member to the third terminal post.

Claim 12

A transducer apparatus as defined in claim 8, further comprising an alignment bar supported by said main lever above its base plate below said plunger element and screw means for selectively varying the distance of said alignment bar from said base plate at its point of contact with said plunger element.

Claim 13

A transducer apparatus as defined in claim 7, wherein said spring means comprises an elongated member disposed in space relation along said main lever and having one end portion rigidly supported at said pivot member and the other end portion extending beyond the point of contact of said force transfer member with said main lever, said other end portion having resilient characteristics and disposed in engaging relation with said main lever to urge said main lever against said force transfer member.

Claim 14

A transducer apparatus as defined in claim 11, further comprising a differential range adjust means for selectively varying the point of contact in a lengthwise direction between said resilient end portion of said elongated spring member and said main lever to thereby vary its effective spring rate.

Claim 15

A transducer apparatus as defined in claim 12, wherein said differential range adjust means comprises a block member slidably mounted on said main lever and having a spacer portion between said resilient end portion of said spring member and said main lever, and an adjustment screw rotatably mounted on said main lever in a lengthwise direction and in threaded engagement with a threaded bore in said block member.

Claim 16

A transducer apparatus as defined in claim 11, further comprising set point means for varying the transverse angle between said other end portion of said spring member and said main lever to selectively adjust the point at which the pressure in said pressure chamber will actuate said variable resistance means.

Claim 17

A transducer apparatus as defined in claim 14, wherein said set point means comprises a set screw in threaded relation with an aperture in said bottom wall of said frame with its uppEr end engaging the outer end of said one end portion of said elongated spring member, where the turning of said set screw changes the transverse angle between said resilient end portion of said spring member and said main lever.

Claim 20

An apparatus as defined in claim 16, further comprising set point means for varying the transverse angle between said resilient end portion of said spring member and said main lever to selectively adjust the point at which the pressure will actuate said electrical responsive means.