Pressure indicator and switch

Claim 2

In a combination pressure gauge and switch having a housing journaling a helix bearing an indicator arm movable therewith for cooperation with scale indicia facing outwardly of the housing, means for moving said helix in accordance with pressures sensed by the gauge, a pivotally mounted set point indicator arm cooperating with the scale indicia, a photocell movable with the set point arm and positioned to be exposed to a light source adjacent the helix for rendering same electrically conductive and to be shielded from same by a light shield movable with the helix at a predetermined position of the set point arm relative to the scale indicia whereby the cell is non conductive, and electrical circuit means including said light source and said photocell for utilizing the position of the indicator arm relative to said set point arm to activate and deactivate an electrical relay coil, the improvement wherein: said light source is aligned with the axis of said helix, said light shield being movable about said helix axis and being shaped to be concentric therewith, said circuit means including first and second switching semiconductors, one of said semiconductors being in circuit controlling relation with said coil and the other of said transistors being in bias controlling relation to the first transistor, and means connecting said second transistor to a dual polarity direct current power supply, said photocell being electrically interposed in said connecting means to change the bias application to the second transistor in accordance with the exposure or shielding of the photocell with reference to the light source.

Claim 3

The improvement set forth in claim 1 wherein: said relay coil comprises a component of a relay subassembly pack adapted to be secured to the housing or remotely located therefrom.

Claim 4

In a combination pressure gauge and switch device comprising an open ended housing having a helix journaled in same for rotation about its axis, with the helix having a pressure indicator arm movable therewith for cooperation with scale indicia facing outwardly of the housing open end, a magnet cooperating with the helix for producing pivoting movement of said helix in response to linear movement of said magnet longitudinally of the axis of the helix under the action of pressures sensed by the gauge, with the helix being journaled at the free end of a cantilevered supporting wishbone secured to the housing at the other end of same, a set point indicator arm operably mounted on the wishbone for pivotal movement about the helix axIs and cooperating with the scale indicia, a photocell movable with the set point indicator and positioned to be exposed to a light source adjacent the helix for rendering same electrically conductive and to be shielded from same by a light shield movable with the helix at a predetermined position of the set point arm relative to the scale indicia whereby the photocell is non conductive, electrical circuit means including said light source and said photocell for utilizing the position of the indicator arm relative to said set point arm to activate and deactivate an electrical device, means for adjustably positioning said free end of said wishbone to set the pressure indicator arm on the zero datum of the scale indicia, and a cover applied over the open end of the housing including a transparent portion for viewing said scale indicia and said arms, the improvement wherein: said wishbone comprises a plate member of one piece construction defining between said ends thereof a planar portion at which the scale indicia are located, said free end of said wishbone being indented outwardly of the housing relative to said planar portion to define a planar mounting panel portion in which one end of said helix is journaled, said set point arm being secured to a gear segment journaled on the side of said wishbone panel portion facing outwardly of said housing for pivotal movement about the axis of said helix, gear means journaled in said side of said wishbone panel portion for pivoting said gear segment to position said set point arm relative to said scale indicia, said free end of said wishbone having a flange portion extending normally of said wishbone panel portion and terminating in a ledge that is in substantial parallelism with said wishbone in which the other end of said helix is journaled, said wishbone flange portion being notched at one side of said helix and said light shield being on a support mounted on said helix and extending through said wishbone notch to dispose said light shield above said wishbone panel portion for movement about said helix axis, said light source comprising a light bulb mounted above said wishbone mounting portion on said helix axis, with said photocell being mounted on said gear segment on the outwardly facing side thereof.

Claim 5

In a combination pressure gauge and switch device comprising an open ended housing having a helix journaled in same for rotation about its axis, with the helix having a pressure indicator arm movable therewith for cooperation with scale indicia facing outwardly of the housing open end, a magnet cooperating with the helix for producing pivoting movement of said helix in response to linear movement of said magnet longitudinally of the axis of the helix under the action of pressures sensed by the gauge, with the helix being journaled at the free end of a cantilevered supporting wishbone secured to the housing at the other end of same, a set point indicator arm operably mounted on the wishbone for pivotal movement about the helix axIs and cooperating with the scale indicia, a photocell movable with the set point indicator and positioned to be exposed to a light source adjacent the helix for rendering same electrically conductive and to be shielded from same by a light shield movable with the helix at a predetermined position of the set point arm relative to the scale indicia whereby the photocell is non conductive, electrical circuit means including said light source and said photocell for utilizing the position of the indicator arm relative to said set point arm to activate and deactivate an electrical device, means for adjustably positioning said free end of said wishbone to set the pressure indicator arm on the zero datum of the scale indicia, and a cover applied over the open end of the housing including a transparent portion for viewing said scale indicia and said arms, the improvement wherein: said wishbone comprises a plate member of one piece construction defining between said ends thereof a planar portion at which the scale indicia are located, said free end of said wishbone being indented outwardly of the housing relative to said planar portion to define a planar mounting panel portion in which one end of said helix is journaled, said set point arm being secured to a gear segment journaled on the side of said wishbone panel portion facing outwardly of said housing for pivotal movement about the axis of said helix, gear means journaled in said side of said wishbone panel portion for pivoting said gear segment to position said set point arm relative to said scale indicia, said free end of said wishbone having a flange portion extending normally of said wishbone panel portion and terminating in a ledge that is in substantial parallelism with said wishbone in which the other end of said helix is journaled, said wishbone flange portion being notched at one side of said helix and said light shield being on a support mounted on said helix and extending through said wishbone notch to dispose said light shield above said wishbone panel portion for movement about said helix axis, said light source comprising a light bulb mounted above said wishbone mounting portion on said helix axis, with said photocell being mounted on said gear segment on the outwardly facing side thereof.

Claim 6

The improvement set forth in claim 3 wherein: said gear means is operated by a handle journaled in said cover and having a splined connection with said gear means for accommodating said adjustable positioning of said wishbone.

Claim 7

The improvement set forth in claim 3 wherein: said gear means includes means for effecting pivotal movement of said set point arm in the same direction that said handle is turned.

Claim 8

The improvement set forth in claim 3 wherein: said electrical circuit means includes a prong structure extending through said housing, said prong structure comprising: a multi-pronged plug mounted in a boss formed in said housing, said boss projecting inwardly of the housing and said plug including a polygonal head disposed exteriorly of said housing, with said plug extending short of the inwardly projecting portion of said boss with said prongs projecting through said boss portion into said housing for securement to wire means extending to said cell and said light, said plug and said prongs being potted in place about said boss portion.

Claim 9

The improvement set forth in claim 6 including: a locking clip cooperating between said plug head and said housing for fixing said plug against threading movement relative to said housing, said clip comprising an annular member interposed between said plug head and said housing and having a tab in keyed relation to said housing and opposed flange portions seated against opposed faces of said plug head.

Claim 10

The improvement set forth in claim 3 wherein: said housing has a flexible diaphragm mounted therein separating high and low pressure chambers, with said low pressure chamber beinG on the back side of said housing, said magnet being mounted on a leaf spring connected to said diaphragm to provide said linear movement of said magnet.

Claim 11

The improvement set forth in claim 3 wherein: said housing includes a back wall having an exterior annular bearing surface, said back wall having a cupped cap affixed thereto against said bearing surface, with a diaphragm being clamped between said cap and housing back wall, said housing back wall being formed with an opening aligned with said diaphragm, said magnet being mounted on a leaf spring connected to said diaphragm to provide said linear movement of said magnet, said cap being formed for connection to a source of fluid pressure.

Claim 12

The improvement set forth in claim 6 including a generally U-shaped bracket secured to the back wall of said housing, said bracket having a web that is fixed to said housing back wall and a pair of legs extending normally of said back wall, said legs having secured therebetween a panel board that extends parallelly of said housing back wall, said panel board having said electrical device secured thereto on the side of same that faces said housing back wall, with one of said legs being formed with a projecting end portion equipped with a pronged electrical connection plug adapted for plug in connection to electrical circuiting that is separate from said gauge, wiring means extending between said housing multiprong plug and said side of said panel board for connecting said electrical device in said circuit means, and wiring means extending between the other side of said panel board and said pronged connection for effecting connection of said circuit means to a source of electrical power.

Claim 13

The improvement set forth in claim 10 including: a cover received over said bracket in abutting relation to said housing, said cover being slotted in one side wall for frictional sliding engagement with said bracket one leg.

Claim 14

The improvement set forth in claim 3 wherein: said electrical device comprises a relay coil, and wherein said circuit means comprises: a first switching transistor having its collector and emitter in series circuit with said coil, a second switching transistor having the base of the first transistor connected to a series circuit which includes the second transistor collector and emitter, and a controlling series circuit connected to a direct current dual polarity power supply and including the photocell in series circuit therewith and having the base of said second transistor connected thereto, whereby when said photocell is shielded from said light source said first transistor is biased to energize said coil, and when said photocell is exposed to said light source, said first transistor is biased to de-energize said coil.

Claim 15

The improvement set forth in claim 3 including: a second set point arm operably mounted on the wishbone for pivotal movement about the helix axis and cooperating with the scale indicia, said second set point arm being secured to a second gear segment journaled in said outwardly facing side of said wishbone panel portion, gear means journaled in said side of said wishbone panel portion for pivoting said second gear segment independently of the first gear segment, said second gear segment having a photocell mounted on same on the outwardly facing side thereof for exposure to said light source, said light shield shielding the second photocell from the light source in at a predetermined position of the second set point arm relative to the scale indicia, whereby the second photocell is nonconductive, said second photocell being incorporated in said electrical circuit means for utilizing the position of the indicator arm relative to the second set point arm to activate and deactivate a second electrical device.