Semiautomatic door actuated vehicle leveling system

Claim 2

A semiautomatic vehicle leveling system for maintaining a predetermined height relationship between the sprung and unsprung mass of a vehicle comprising: fluid spring means adapted to be connected between the sprung and the unsprung mass of a vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, circuit means operative to energize said electric motor including a motor control switch having an energizable component for maintaining said motor energized during a pump-up phase of operation, a hold circuit for said energizable component including a three terminal switching device, means including manually operated switch means for conditioning said three terminal switching device to initiate the pump-up phase of operation, a height controller responsive to a predetermined height correction to direct fluid from said fluid spring means, pressure responsive switch means connected to said height controller and operative upon fluid being exhausted from said fluid spring means to condition said hold circuit so as to deenergize said motor to terminate the pump-up phase of operation.

Claim 3

A semiautomatic vehicle leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle having a door comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, circuit means operative to energize said electric motor including a vehicle door switch and means responsive to door switch operation to complete the energization circuit means for said motor following door closure to initiate a pump-up phase of operation, a height controller responsive to a predetermined height correction to direct fluid from said fluid spring means, pressure-responsive switch means fluidly connected to said height controller and operative upon fluid being exhausted from said fluid spring means to condition said circuit means so as to deenergize said motor to terminate the pump-up phase of operation.

Claim 4

A semiautomatic vehicle leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle having a door comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, circuit means operative to energize said electric motor including a vehicle door switch and means responsive to door switch operation to complete the energization circuit means for said motor following door closure to initiate a pump-up phase of operation, a height controller responsive to a predetermined height correction to direct fluid from said fluid spring means, pressure-responsive switch means fluidly connected to said height controller and operative upon fluid being exhausted from said fluid spring means to condition said circuit means so as to deenergize said motor to terminate the pump-up phase of operation.

Claim 5

A semiautomatic vehicle leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, circuit means operative to energize said electric motor to produce the increase in pressure of said fluid spring means during a pump-up phase of operation including manually operated start switch means to initiate the pump-up phase of operation, said circuit means including a relay-operated switch having a coil energizable to condition said relay switch to control motor energization, a hold circuit for said coil including a three terminal switching device and a pressure responsive switch, said switching device being operative in response to actuation of said start switch means to maintain said coil conditioned to cause said relay switch to maintain said motor energized during the pump-up phase of operation, a height controller responsive to a predetermined height relationship between the sprung and unsprung mass following pumpup and operative to exhaust a predetermined amount of fluid from said fluid spring means, said pressure-responsive switch operative upon fluid being exhausted from said fluid spring means to condition said holding circuit switch so as to deenergize said coil to terminate motor energization and the pump-up phase of operation.

Claim 6

A semiautomatic vehicle leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, circuit means operative to energize said electric motor to produce the increase in pressure of said fluid spring means during a pump-up phase of operation including manually operated start switch means to initiate the pump-up phase of operation, said circuit means including a relay-operated switch having a coil energizable to condition said relay switch to control motor energization, a hold circuit for said coil including a three terminal switching device and a pressure responsive switch, said switching device being operative in response to actuation of said start switch means to maintain said coil conditioned to cause said relay switch to maintain said motor energized during the pump-up phase of operation, a height controller responsive to a predetermined height relationship between the sprung and unsprung mass following pumpup and operative to exhaust a predetermined amount of fluid from said fluid spring means, said pressure-responsive switch operative upon fluid being exhausted from said fluid spring means to condition said holding circuit switch so as to deenergize said coil to terminate motor energization and the pump-up phase of operation.

Claim 7

A semiautomatic leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressOr having its outlet connected directly to said fluid spring means, an electric motor with a run winding for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, a battery having a positive terminal, a primary energization circuit for said motor including a motor control switch electrically connecting said positive terminal to said run winding, said motor control switch having an electrically energizable component, a hold circuit for said component including a three terminal semiconductor switching device and a normally closed pressure-responsive switch, a height controller operative upon a predetermined height correction to direct fluid from said spring means to said pressure-responsive pressure-responsive switch to condition it to deenergize the energizable component of the motor control switch, said semiconductor switching device having a control terminal, pulse-forming circuit means including a capacitor electrically connected to said positive terminal of the battery, means including a manually-operated start switch normally open to cause said capacitor to be charged by said vehicle battery, said start switch being closed and then being reopened to initiate the beginning of a pump-up phase by conditioning said capacitor to be recharged on switch opening to thereby trigger said semiconductor switching device conductive, means for maintaining a signal on said control terminal of said semiconductor switching device during a pump-up phase to maintain said hold circuit, said pressure responsive switch maintaining said hold circuit until fluid is exhausted from the fluid spring means and being conditioned thereby to open said hold circuit to terminate the pump-up phase.

Claim 8

A semiautomatic leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressOr having its outlet connected directly to said fluid spring means, an electric motor with a run winding for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, a battery having a positive terminal, a primary energization circuit for said motor including a motor control switch electrically connecting said positive terminal to said run winding, said motor control switch having an electrically energizable component, a hold circuit for said component including a three terminal semiconductor switching device and a normally closed pressure-responsive switch, a height controller operative upon a predetermined height correction to direct fluid from said spring means to said pressure-responsive pressure-responsive switch to condition it to deenergize the energizable component of the motor control switch, said semiconductor switching device having a control terminal, pulse-forming circuit means including a capacitor electrically connected to said positive terminal of the battery, means including a manually-operated start switch normally open to cause said capacitor to be charged by said vehicle battery, said start switch being closed and then being reopened to initiate the beginning of a pump-up phase by conditioning said capacitor to be recharged on switch opening to thereby trigger said semiconductor switching device conductive, means for maintaining a signal on said control terminal of said semiconductor switching device during a pump-up phase to maintain said hold circuit, said pressure responsive switch maintaining said hold circuit until fluid is exhausted from the fluid spring means and being conditioned thereby to open said hold circuit to terminate the pump-up phase.

Claim 9

A semiautomatic leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor with a run winding for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, a battery having a positive terminal, a primary energization circuit for said motor including a motor control switch electrically connecting a positive terminal of a battery to said run winding, said motor control switch having an electrically energizable component, a hold circuit for said component including a three terminal semiconductor switching device and a normally closed pressure-responsive switch, a height controller operative upon a predetermined height correction to direct fluid from said spring means to said pressure-responsive switch to condition it to deenergize the energizable component of said motor control switch, said semiconductor switching device having a control terminal, pulse-forming circuit means including a capacitor electrically connected to the positive terminal of the battery, a door switch maintained normally open when the door of a vehicle is closed to cause said capacitor to be charged by said vehicle battery, said door switch being closed when the door is open and electrically connected to ground for discharging said capacitor to trigger said semiconductor switching device conductive when the vehicle door is closed, means for maintaining a signal of said control terminal of said semiconductor switching device during a pump-up phase of operation to maintain said hold circuit, said pressure-responsive switch maintaining said hold circuit until fluid is exhausted from said fluid spring means and being conditioned thereby to open said hold circuit to terminate the pump-up phase.

Claim 10

A semiautomatic leveling system for maintaining a predetermined height relationship between the sprung and the unsprung mass of a vehicle comprising; fluid spring means adapted to be connected between the sprung and the unsprung mass of vehicle for maintaining a predetermined height relationship therebetween, a pressure source including a compressor having its outlet connected directly to said fluid spring means, an electric motor with a run winding for driving said compressor to increase the pressure level in said fluid spring means to compensate for increased static loading on the sprung mass of a vehicle, a battery having a positive terminal, a primary energization circuit for said motor including a motor control switch electrically connecting a positive terminal of a battery to said run winding, said motor control switch having an electrically energizable component, a hold circuit for said component including a three terminal semiconductor switching device and a normally closed pressure-responsive switch, a height controller operative upon a predetermined height correction to direct fluid from said spring means to said pressure-responsive switch to condition it to deenergize the energizable component of said motor control switch, said semiconductor switching device having a control terminal, pulse-forming circuit means including a capacitor electrically connected to the positive terminal of the battery, a door switch maintained normally open when the door of a vehicle is closed to cause said capacitor to be charged by said vehicle battery, said door switch being closed when the door is open and electrically connected to ground for discharging said capacitor to trigger said semiconductor switching device conductive when the vehicle door is closed, means for maintaining a signal of said control terminal of said semiconductor switching device during a pump-up phase of operation to maintain said hold circuit, said pressure-responsive switch maintaining said hold circuit until fluid is exhausted from said fluid spring means and being conditioned thereby to open said hold circuit to terminate the pump-up phase.

Claim 11

An electrical circuit for controlling an electric drive motor in a semiautomatic vehicle leveliNg system comprising; a primary energization circuit including a motor control switch for electrically connecting a positive battery terminal to the run winding of the motor, said motor control switch having an electrically energizable component, a hold circuit for said component including a three terminal semiconductor switching device and a normally closed pressure-responsive switch operative upon a change in the static loading on the vehicle to deenergize the energizable component of the motor control switch, said semiconductor switching device having a control terminal, pulse-forming circuit means including a capacitor adapted to be electrically connected to the positive terminal of the battery, a manually operated start switch maintained normally open to cause said capacitor to be charged by the vehicle battery, said start switch being closed and then being reopened to initiate the beginning of a pump-up phase by conditioning said capacitor to be recharged on switch opening to trigger said semiconductor switching device conductive, means for maintaining a signal on said control terminal of said semiconductor switching device during a pump-up phase to maintain said hold circuit, said pressure responsive switch maintaining said hold circuit, until fluid is exhausted from the fluid spring means and being conditioned thereby to open said hold circuit.

Claim 12

An electrical circuit for controlling an electric drive motor in a semiautomatic vehicle leveliNg system comprising; a primary energization circuit including a motor control switch for electrically connecting a positive battery terminal to the run winding of the motor, said motor control switch having an electrically energizable component, a hold circuit for said component including a three terminal semiconductor switching device and a normally closed pressure-responsive switch operative upon a change in the static loading on the vehicle to deenergize the energizable component of the motor control switch, said semiconductor switching device having a control terminal, pulse-forming circuit means including a capacitor adapted to be electrically connected to the positive terminal of the battery, a manually operated start switch maintained normally open to cause said capacitor to be charged by the vehicle battery, said start switch being closed and then being reopened to initiate the beginning of a pump-up phase by conditioning said capacitor to be recharged on switch opening to trigger said semiconductor switching device conductive, means for maintaining a signal on said control terminal of said semiconductor switching device during a pump-up phase to maintain said hold circuit, said pressure responsive switch maintaining said hold circuit, until fluid is exhausted from the fluid spring means and being conditioned thereby to open said hold circuit.