Pressure indicating system

Claim 2

In a power braking system a pressure responsive means comprising: a conductive housing which is adapted to be threaded to a grounded fitting of a pressure line of said power braking system; a plunger element slidably received in a first bore in said housing and having one end exposed to said variable pressure in said pressure line while the other end projects through said housing into a second bore in said housing; said other end having installed thereon an insulator plug for receiving a conductive cap; said second bore being adapted to receive a nonconductive plug which carries an outer conductive contact and an inner conductive contact separated by a nonconductive member; a conductive resilient means being disposed between said outer conductive contact and said conductive cap to preload said conductive cap against said housing so as to provide electrical continuity between said outer conductive contact and said housing; said plunger element being slidably responsive to said power braking system pressure increases so as to move said conductive cap axially away from said housing and into engagement with said inner conductive contact.

Claim 3

In a power braking system a pressure responsive means comprising: a conductive housing which is adapted to be threaded to a grounded fitting of a pressure line of said power braking system; a plunger element slidably received in a first bore in said housing and having one end exposed to said variable pressure in said pressure line while the other end projects through said housing into a second bore in said housing; a seal means intermediate said plunger element and said housing to exclude said variable pressure from said second bore; said other end having installed thereon an insulator plug for receiving a conductive cap; said second bore threaded to receive a threaded nonconductive plug being adapted to carry an outer conductive contact and an inner conductive contact separated by a nonconductive member; a conductive resilient means being disposed between said outer conductive contact and said conductive cap to preload said conductive cap against said housing so as to provide electrical continuity between said outer conductive contact and said housing; said plunger element being slidably responsive to said power braking system pressure increases so as to move said conductive cap axially away from said housing and into engagement with said inner conductive contact; said conductive resilient means being of predetermined preload so that said plunger element will not slidably respond to a reasonably low pressure level of said power braking system so as to maintain electrical continuity between said outer contact and said housing; said plungeR element slidably responding to an intermediate pressure level of said power braking system to move said conductive cap away from said housing so as to disrupt electrical continuity between said outer contact and said housing; said plunger element slidably responding to a reasonably high pressure level of said power braking system to move said conductive cap into contact with said inner conductive contact establishing electrical continuity between said outer and inner contacts.

Claim 4

In a power braking system a pressure responsive means comprising: a conductive housing which is adapted to be threaded to a grounded fitting of a pressure line of said power braking system; a plunger element slidably received in a first bore in said housing and having one end exposed to said variable pressure in said pressure line while the other end projects through said housing into a second bore in said housing; a seal means intermediate said plunger element and said housing to exclude said variable pressure from said second bore; said other end having installed thereon an insulator plug for receiving a conductive cap; said second bore threaded to receive a threaded nonconductive plug being adapted to carry an outer conductive contact and an inner conductive contact separated by a nonconductive member; a conductive resilient means being disposed between said outer conductive contact and said conductive cap to preload said conductive cap against said housing so as to provide electrical continuity between said outer conductive contact and said housing; said plunger element being slidably responsive to said power braking system pressure increases so as to move said conductive cap axially away from said housing and into engagement with said inner conductive contact; said conductive resilient means being of predetermined preload so that said plunger element will not slidably respond to a reasonably low pressure level of said power braking system so as to maintain electrical continuity between said outer contact and said housing; said plungeR element slidably responding to an intermediate pressure level of said power braking system to move said conductive cap away from said housing so as to disrupt electrical continuity between said outer contact and said housing; said plunger element slidably responding to a reasonably high pressure level of said power braking system to move said conductive cap into contact with said inner conductive contact establishing electrical continuity between said outer and inner contacts.

Claim 5

In a power braking system, a pressure indicating system comprising: a conductive housing secured to a grounded fitting of a pressure line of said power braking system; a plunger member slidably received in a first bore in said housing, said plunger member having one end exposed to the fluid pressure in said pressure line while the other end projects through said housing into a second bore in said housing; an insulator plug secured to said other end of said plunger having a conductive cap received thereon; a nonconductive plug closing said second bore having an outer conductive contact and an inner conductive contact separated by a nonconductive member; a conductive resilient member located between said conductive cap and said outer conductive contact for biasing said conductive cap against said housing to provide electrical conductivity between said outer conductive contact and said housing; said plunger member being slidably responsive to the fluid pressure in said pressure line to move said conductive cap axially away from said housing and into engagement with said inner conductive contact; electronic control means connected to said inner conductive contact and said outer conductive contact for receiving a signal corresponding to the position of said conductive cap; and indicator means connected to said electronic control means for indicating variable pressure levels in said power braking system.

Claim 6

In a power braking system, a pressure indicating system comprising: a conductive housing secured to a grounded fitting of a pressure line of said power braking system; a plunger member slidably received in a first bore in said housing, said plunger member having one end exposed to the fluid pressure in said pressure line while the other end projects through said housing into a second bore in said housing; an insulator plug secured to said other end of said plunger having a conductive cap received thereon; a nonconductive plug closing said second bore having an outer conductive contact and an inner conductive contact separated by a nonconductive member; a conductive resilient member located between said conductive cap and said outer conductive contact for biasing said conductive cap against said housing to provide electrical conductivity between said outer conductive contact and said housing; said plunger member being slidably responsive to the fluid pressure in said pressure line to move said conductive cap axially away from said housing and into engagement with said inner conductive contact; electronic control means connected to said inner conductive contact and said outer conductive contact for receiving a signal corresponding to the position of said conductive cap; and indicator means connected to said electronic control means for indicating variable pressure levels in said power braking system.

Claim 7

In a power braking system, a pressure indicating system comprising: pressure responsive means connected to the power braking system, said pressure responsive means being responsive to variable fluid pressure levels in said power braking system, said pressure responsive means having operable modes corresponding to low, intermediate and high fluid pressure in said power braking system, said pressure responsive means having first and second terminals to identify the mode of operation present in the power braking system; electronic control means connected to a source of voltage, an electrical ground and said first and second terminal of pressure responsive means, said electronic control means including, a generator producing an output which alternately switches from an ON period to an OFF period; voltage drop means connected to said source of voltage and said first terminal; a control element for regulating voltage across and current from said electronic control means, said control element having an input connected to said second terminal and said generator, said second terminal receiving a signal corresponding to ground, an open circuit, and a voltage less than said source of voltage in a direct relationship to said low, intermediate and high fluid pressure mode of operation; and indicator means connected to the output from said control element to communicate to an operator the fluid pressure level in said power braking system, said indicator means being continuously activated during low fluid pressure, intermittently activated during intermediate fluid pressure and deactivated during high fluid pressure in said power braking system.

Claim 8

In a power braking system, a pressure indicating system comprising: pressure responsive means connected to the power braking system, said pressure responsive means being responsive to variable fluid pressure levels in said power braking system, said pressure responsive means having operable modes corresponding to low, intermediate and high fluid pressure in said power braking system, said pressure responsive means having first and second terminals to identify the mode of operation present in the power braking system; electronic control means connected to a source of voltage, an electrical ground and said first and second terminal of pressure responsive means, said electronic control means including, a generator producing an output which alternately switches from an ON period to an OFF period; voltage drop means connected to said source of voltage and said first terminal; a control element for regulating voltage across and current from said electronic control means, said control element having an input connected to said second terminal and said generator, said second terminal receiving a signal corresponding to ground, an open circuit, and a voltage less than said source of voltage in a direct relationship to said low, intermediate and high fluid pressure mode of operation; and indicator means connected to the output from said control element to communicate to an operator the fluid pressure level in said power braking system, said indicator means being continuously activated during low fluid pressure, intermittently activated during intermediate fluid pressure and deactivated during high fluid pressure in said power braking system.

Claim 9

In a power braking system, means for determining the operational fluid pressure available in the system, said means comprising: pressure responsive means connected to the power braking system for registering variable pressure levels in the power braking system, said pressure responsive means having a mode of operation corresponding to low, intermediate and high fluid pressure in The system, said pressure responsive means having different electrical circuits for carrying a signal resulting from the mode of operation; electronic control means for receiving said signal resulting from the mode of operation, said electronic control means allowing current flow in response to said signal, said current flow being distinguishable for each mode of operation; and indicator means for receiving said distinguishable current flow to communicate to an operator the mode of fluid pressure operation associated therewith.

Claim 10

In a power braking system, means for determining the operational fluid pressure available in the system, said means comprising: pressure responsive means connected to the power braking system for registering variable pressure levels in the power braking system, said pressure responsive means having a mode of operation corresponding to low, intermediate and high fluid pressure in The system, said pressure responsive means having different electrical circuits for carrying a signal resulting from the mode of operation; electronic control means for receiving said signal resulting from the mode of operation, said electronic control means allowing current flow in response to said signal, said current flow being distinguishable for each mode of operation; and indicator means for receiving said distinguishable current flow to communicate to an operator the mode of fluid pressure operation associated therewith.

Claim 11

The power braking system, as recited in claim 5, wherein said indicator means includes: a lamp energized by said distinguishable current flow for visually indicating to an operator the mode of operation, said electronic control means allowing current to flow during periods of low fluid pressure mode of operation causing said lamp to continually glow, to intermittently flow during periods of intermediate fluid pressure causing said lamp to blink and to interrupt flow during periods of high fluid pressure causing said lamp to remain deenergized.

Claim 12

In the power braking system, as recited in claim 6, wherein said electronic control means includes: a source of electrical energy; switching means for regulating said distinguishable current flow to said lamp, said switching means being connected to a first circuit of said different circuits for carrying a signal of the mode of operation of said pressure responsive means and said source of electrical energy; voltage drop means connected to said source of electrical energy and said switching means for carrying a signal of the mode of operation through a second circuit of said different circuits; and means connected to said source of electrical energy and said switching means for generating ON-OFF current flow in response to the intermediate mode of operation in said pressure responsive means.

Claim 13

In the power braking system, as recited in claim 7, wherein during periods of low fluid pressure said first circuit carries a signal for this mode of operation causing said switching means to continually supply current flow for energizing said lamp.

Claim 14

In the power braking system, as recited in claim 8, wherein during periods of high fluid pressure a signal for this mode of operation is carried by said second circuit through said voltage drop means and by said first circuit to said switching means causing current flow from said switching means to be interrupted.

Claim 15

The power braking system, as recited in claim 9, further including: test means connected to said source of electrical energy for checking the operativeness of the electronic control means and indicator means in response to closing the ignition switch by an operator.

Claim 16

The power braking system, as recited in claim 10, wherein said pressure responsive means includes: a housing having a first bore and a second bore, said first bore being connected to receive fluid pressure from said braking system; fluid responsive means located in said first bore adapted to move in response to variations in fluid pressure; receptive means located in said second bore for registering changes in position of said wall means; and transmitting means connected to said receptive means for conveying a signal through one of said electrical circuits corresponding to the mode of operation as determined by the position of said fluid responsive means.

Claim 17

The power braking system, as recited in claim 11, wherein said fluid responsive means includes: a plunger located in said first bore with a shaft which extends into said second bore, said shaft being slidable in an opening of said housing, said plunger having a larger diameter than the opening in said housing through which said shaft extends, said larger diameter coming into contact with said housing to limit the movement of said plunger in said first bore during a fluid pressure mode of operation.

Claim 18

The power braking system, as recited in claim 12, wherein said receptive means includes: cap means having an electrical nonconductive interior secured to said shaft and an electrical conductive exterior, said electrical conductive exterior providing a contact between the movable plunger and the electrical circuits corresponding to the mode of operation representing the fluid pressure in said braking system.

Claim 19

The power braking system, as recited in claim 13, wherein said transmitting means includes: a plug means for closing said second bore to form a chamber therein, said plug member having an outer nonconductive member surrounding a plurality of different electrical circuits, each of said plurality of electrical circuits being connected to said electronic control means for transmitting a mode of operation signal.

Claim 20

The power braking system, as recited in claim 14, wherein said transmitting means further includes: resilient means located between said plug means and said cap means for urging said plunger member away from the opening in said housing through which the shaft extends to thereby require a predetermined fluid pressure to move said plunger into a mode of operation.

Claim 21

The power braking system, as recited in claim 15, wherein said resilient means provides an electrical path between said first circuit and said second circuit during the high pressure mode of operation permitting a signal to be carried to said switching means for interrupting current flow to said lamp.

Claim 22

The power braking system, as recited in claim 16, further including: a seal surrounding said plunger and contacting said first bore for preventing said variable pressure access to said second bore through the opening for the shaft in said housing.

Claim 23

The power barking system, as recited in claim 17, further including: retaining means located in said first bore for captivating said plunger in said first bore while permitting fluid pressure to be communicated fully to said first bore.

Claim 24

The power braking system, as recited in claim 18, wherein said plug means is adjustable within said second bore to assure an electrical connection between said conductive exterior of the cap means and said second circuit leading to the electronic control means.