US3739813A — Power and speed control for double-acting cylinde…

Claim 1

Independent Claim 335 words

A power and speed control system for a cylinder-and-piston motor including in combination first valve means for controlling the working fluid supply to, and exhaust from, one end of a motor cylinder, second valve means for controlling the supply and exhaust of working fluid for the other end of the motor, a housing in which the first and second valve means are located in generally parallel relation to one another and oriented to move in the same direction for comparable operations, common motiontransmitting means for moving both the first and second valve means in opposite directions when said motion-transmitting means moves in different directions, an electro-magnetic actuator that moves the motion-transmitting means in one direction, a second electro-magnetic actuator that moves the motion-transmitting means in a different direction, each valve means including a valve element for controlling flow of fluid to the motor and another valve element for controlling exhaust flow of fluid from the motor, one of the valve elements of each of said first and second valve means being flow-responsive and having means comprising a restricted passage through which the working fluid supply passes, a movable wall connected to the flow-responsive valve element and movable as a unit therewith, the wall being exposed on opposite sides to the working fluid pressure at the upstream and downstream ends, respectively, of the restricted passage, the upstream pressure being on the side of the movable wall to urge the flow-responsive valve element toward closed position with progressively greater force as the rate of flow through the restricted passage increases whereby the rate of flow of working fluid through the valve means is proportional to the current supplied to the electro-magnetic actuators to hold the respective flow-responsive valve elements in open position, and current control means including a single control lever for regulating a current supply to each of the electro-magnetic actuators, the current control means being adjustable into different positions in accordance with the desired rate of flow of working fluid past the flow-responsive valve elements.

Claim 2

Dependent Claim 335 words

A power and speed control system for a cylinder-and-piston motor including in combination first valve means for controlling the working fluid supply to, and exhaust from, one end of a motor cylinder, second valve means for controlling the supply and exhaust of working fluid for the other end of the motor, a housing in which the first and second valve means are located in generally parallel relation to one another and oriented to move in the same direction for comparable operations, common motiontransmitting means for moving both the first and second valve means in opposite directions when said motion-transmitting means moves in different directions, an electro-magnetic actuator that moves the motion-transmitting means in one direction, a second electro-magnetic actuator that moves the motion-transmitting means in a different direction, each valve means including a valve element for controlling flow of fluid to the motor and another valve element for controlling exhaust flow of fluid from the motor, one of the valve elements of each of said first and second valve means being flow-responsive and having means comprising a restricted passage through which the working fluid supply passes, a movable wall connected to the flow-responsive valve element and movable as a unit therewith, the wall being exposed on opposite sides to the working fluid pressure at the upstream and downstream ends, respectively, of the restricted passage, the upstream pressure being on the side of the movable wall to urge the flow-responsive valve element toward closed position with progressively greater force as the rate of flow through the restricted passage increases whereby the rate of flow of working fluid through the valve means is proportional to the current supplied to the electro-magnetic actuators to hold the respective flow-responsive valve elements in open position, and current control means including a single control lever for regulating a current supply to each of the electro-magnetic actuators, the current control means being adjustable into different positions in accordance with the desired rate of flow of working fluid past the flow-responsive valve elements.

Claim 3

Dependent Claim 75 words

The control system described in claim 1 characterized by the motion-transmitting means including a rocker arm, a pivotal support for the rocker arm intermediate the ends thereof, each of said first and second valve means having a push rod in position to contact with the rocker arm on a different side of the pivotal support for causing the valve means to move in opposite directions as the rocker arm moves angularly about said pivotal support.

Claim 4

Dependent Claim 55 words

The control system described in claim 2 characterized by eacH of the actuators being a solenoid that operates the rocker arm, the solenoid having the motion-transmitting means that contact with the rocker arm on opposite sides of the pivotal support of the rocker arm and further from the pivotal support than are the push rods.

Claim 5

Dependent Claim 86 words

The flow control system described in claim 3 characterized by the flow-responsive means of each of the valve means including two chambers connected by the restricted passage through which working fluid flows as it passes through said valve means, the connecting passage being of reduced cross section to provide a substantial pressure drop between said chambers, which drop is substantially proportional to the rate of flow of the working fluid, surfaces on different sides of said movable wall being exposed to pressure in the different chambers.

Claim 6

Dependent Claim 31 words

The control system described in claim 4 characterized by working fluid supply means including an adjustable controller for changing the pressure at which working fluid is supplied to the upstream chamber.

Claim 7

Dependent Claim 41 words

The control system described in claim 2 characterized by a manually-operated override for the actuators including a lever connected with the rocker arm and movable angularly to impart rocking movement in both directions about said pivotal support of the rocker arm.

Claim 8

Dependent Claim 48 words

Control system described in claim 1 characterized by the current control means being movable in opposite directions for supplying the regulated amounts of current to the respective electromagnetic actuators and the resulting rate of flow of working fluid to the motor and speed of operation of the motor.

Claim 9

Dependent Claim 139 words

The control system described in claim 7 characterized by the current control means being a potentiometer with a brush having a mid-position and movable in opposite directions from its mid position, means for biasing the brush toward its mid position and for exerting progressively greater force to bring the brush back toward mid position as the displacement of the brush from its mid position is increased, a rheostat for each of the solenoids, one rheostat being on one side of the mid position of the brush and the other rheostat being on the opposite side of the mid position, the brush being selectively movable across the rheostats and each of the rheostats being oriented to increase the current to its solenoid as the brush moves over that rheostat in a direction away from the mid position of the brush.

Claim 10

Dependent Claim 202 words

The control system described in claim 1 characterized by each of the valve means including valve elements having two pairs of contacting surfaces that comprise valves of said valve means, a valve chamber in which each of the valve elements move axially to selectively bring the contacting surfaces of the different pairs together or apart, each of the valve chambers having a port communicating with a different end of the cylinder from the other valve chamber, a working fluid supply passage for each chamber, one pair of contacting surfaces controlling flow of working fluid between the cylinder port and the supply passage, and the other pair of contacting surfaces controlling the flow of working fluid between the cylinder port and the exhaust passage, a housing in which both of the valve chambers are located in substantially parallel relation with one another, a working fluid supply header extending through the housing between the two valve chambers and communicating on its opposite sides with the different valve chambers, an exhaust header extending through the housing between the two valve chambers and connected at its opposite sides with the different valve chambers at locations spaced axially of the valve chambers from the working fluid header.

Claim 11

Dependent Claim 140 words

The control system described in claim 9 characterized by each of the valve means being open for flow of working fluid to the cylinder by axial pressure in one direction and being opened for exhaust of working fluid from the cylinder by axial pressure in the opposite direction, a spring that applies the axial pressure in the diRection that opens the valve means for exhaust, the solenoids supplying the axial pressure in the opposite direction so that the current supplied to the solenoids controls the rate of flow and resulting speed of operation of the motor, the valve means in each housing having a stem extending beyond one end of the housing and comprising part of the motion-transmitting means by which the valve means are operated, the solenoids being located at the end of the housing through which stems extend.

Claim 12

Dependent Claim 46 words

The control system described in claim 9 characterized by adjustable valve means in each of said passages of restricted cross-section for changing the cross-section of said passages to change the rate of flow of working fluid for any given actuating force applied to the valve means.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1976-06-18	1976-12-18	1977-06-19	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1980-06-18	1980-12-18	1981-06-19	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1984-06-18	1984-12-18	1985-06-19	$7700.00	Window Closed / Lapsed

Power and speed control for double-acting cylinder-and-piston motor

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