초록 ▼

A passenger lift includes a lift platform that operates between a generally vertical stowed position in a motor vehicle, a substantially horizontal position at the height of the vehicle floor, and a position resting on the ground. The passenger lift is actuated by hydraulic cylinders responsive to h

A passenger lift includes a lift platform that operates between a generally vertical stowed position in a motor vehicle, a substantially horizontal position at the height of the vehicle floor, and a position resting on the ground. The passenger lift is actuated by hydraulic cylinders responsive to hydraulic pressure and fluid flow from a hydraulic pump driven by a DC electric motor, in cooperation with direction and flow control components. A power-dissipating resistor is switched into and out of series with the motor to effect selected two-speed operation of the motor, the pump, the actuating cylinders and the passenger lift platform, such that one speed is used for deployment and retraction of the lift platform from and to the stowed position, and the second speed is used to raise and lower the lift platform and passenger between the vehicle and the ground.

대표청구항 ▼

We claim: 1. A passenger lift for use in a motor vehicle having a passenger-mobile floor and an electrical power supply, the lift comprising: a lift platform pivotally connected to the vehicle for movement between a generally vertical stowed position in the vehicle, a generally horizontal deployed

We claim: 1. A passenger lift for use in a motor vehicle having a passenger-mobile floor and an electrical power supply, the lift comprising: a lift platform pivotally connected to the vehicle for movement between a generally vertical stowed position in the vehicle, a generally horizontal deployed position at the height of the vehicle floor, and a lowered position at ground level; the lift platform comprising a passenger tray to carry a passenger between said deployed and lowered positions, and back and front walls connected for movement between associated roll-stop positions and lowered positions establishing bridges between the tray and the vehicle floor and ground, respectively, when the platform is in said deployed and lowered positions, respectively; a hydraulic actuator operatively connected to effect selected movement of the lift platform between said positions, the hydraulic actuator being primarily dependent upon fluid flow to effect said movement of the lift platform; a hydraulic pump connected to the hydraulic actuator for supplying said fluid flow; a DC electric motor (i) drivingly coupled to said hydraulic pump for operation thereof and (ii) electrically connected to the vehicle power supply to establish a motor power supply circuit; a fixed-resistance power-dissipating resistor connected to the electric motor; and a switch connected for switching the fixed-resistance of the power-dissipating resistor into and out of series with the motor in the motor power supply circuit to establish two alternate motor operating voltages and associated motor and pump speeds for selected movement of the lift platform between said stowed position and said deployed position at a first speed and between said deployed position and said lowered position at a second speed to effect two-speed operation of the lift; the difference in voltage of the two alternate motor operating voltages being at least the voltage across the resistor when switched in series with the motor in the motor supply circuit. 2. A hydraulic pump assembly for use with a passenger lift mounted in a motor vehicle having a passenger-mobile floor and an electrical power supply, the passenger lift including (i) a lift platform pivotally connected to the vehicle for movement between a generally vertical stowed position in the vehicle, a generally horizontal deployed position at the height of the vehicle floor, and a lowered position at ground level, (ii) hydraulic cylinders connected between the vehicle and the lift platform for moving the lift platform between said positions, (iii) a switch for initiating movement of the lift between said positions, the hydraulic pump assembly comprising: a mounting bracket configured for installation into the vehicle; a hydraulic fluid manifold secured to the mounting bracket, the manifold having fluid connector means for establishing fluidic connection with the hydraulic cylinders; a hydraulic pump secured to the manifold and in fluid communication with the hydraulic cylinders through said fluid connector means for supplying hydraulic pressure and fluid flow to the cylinders and resulting actuation thereof; an electric motor secured to the manifold and drivingly coupled to the pump, the electric motor being electrically connected to the vehicle power supply through the switch; a hydraulic fluid reservoir secured to the manifold for supplying fluid to the pump and receiving return fluid from the hydraulic cylinders; and a power dissipating resistor secured to the mounting bracket, the power dissipating resistor being electrically connected in a first electrical path in series with the motor and the switch, and in parallel with a second electrical path between the motor and the switch, whereby the switch is operative to switch the power dissipating resistor into and out of the electrical supply circuit from the electric power supply to the motor and thereby establish two alternate motor operating voltages and associated pump speeds for selected movement of the lift between said positions. 3. The hydraulic pump assembly as defined in claim 2 in which the manifold includes first and second opposite sides, the hydraulic pump is secured to the first side of the manifold, and the electric motor is secured to the second side of the manifold and is drivingly coupled to the pump through the manifold. 4. The hydraulic pump assembly as defined in claim 3 in which the hydraulic fluid reservoir is secured to the first side of the manifold, and the hydraulic pump is located inside the reservoir. 5. The hydraulic pump assembly as defined in claim 4 in which the mounting bracket is configured for installation of the pump assembly into a preexisting vehicle provided with a passenger lift as a retrofit unit for conversion of the preexisting lift to a two-speed operable lift by switching the power dissipating resistor into and out of the electrical supply circuit from the electric power supply to the motor. 6. A passenger lift for use in a motor vehicle having a floor and an electrical power supply, the lift comprising: a lift platform pivotally connected to the vehicle for movement between a stowed position in the vehicle, a deployed position at the vehicle floor, and a lowered position at ground level; a hydraulic actuator connected between the vehicle and the lift platform for movement of the lift platform between said positions; a hydraulic fluid manifold secured to the vehicle, the manifold having fluid connector means for establishing fluidic connection with the hydraulic actuator; a hydraulic pump secured to the manifold and in fluid communication with the hydraulic actuator through said fluid connector means for supplying hydraulic pressure and fluid flow to the actuator and resulting actuation thereof to effect said movement of the lift platform; a hydraulic fluid reservoir secured to the manifold for supplying fluid to the pump and receiving return fluid from the hydraulic actuator; a DC electric motor secured the manifold and drivingly coupled to the pump for operation thereof, the motor being electrically connected to the vehicle power supply to establish a motor power supply circuit; a power-dissipating resistor connected to the electric motor; and a switch connected for switching the resistor into and out of the motor power supply circuit to establish two alternate motor operating voltages and associated motor and pump speeds for selected movement of the lift platform between said positions. 7. A passenger lift for use in a motor vehicle having a passenger-mobile floor and an electrical power supply, the lift comprising: a lift platform pivotally connected to the vehicle for deployment from a stowed position to a deployed position at the vehicle floor, for lowering from the deployed position to a ground level position, for raising from the ground level position to the deployed position, and for retraction from the deployed position to the stowed position; a hydraulic actuator connected between the vehicle and the lift platform for effecting said deployment, lowering, raising, and retraction of the lift platform, the hydraulic actuator being primarily dependent upon fluid flow to effect said movement of the lift platform; a hydraulic pump in fluid communication with the actuator; a DC electric motor drivingly coupled to the hydraulic pump, the motor being electrically connected to the vehicle power supply to establish a motor power supply circuit, the motor being operative to effect, through said pump and actuator, (i) deployment and lowering of the lift platform when operating in a first direction, and (ii) raising and retraction of the lift platform when operating in a second direction; a fixed-resistance power-dissipating resistor connected to the electric motor; and a switch connected for switching the fixed-resistance of the power-dissipating resistor into and out of series with the motor in the motor power supply circuit to establish two alternate motor operating voltages and associated motor and pump speeds for selected movement of the lift platform between said stowed position and said deployed position at a first speed and between said deployed position and said lowered position at a second speed to effect two-speed operation of the lift; the difference in voltage of the two alternate motor operating voltages being at least the voltage across the resistor when switched in series with the motor in the motor supply circuit.