Did You Know...
...that to encourage use of his new invention, the shopping cart, market owner Sylvan Goldman hired fake shoppers to push the carts around his store in Oklahoma City? Seems his customers were reluctant to give up their hand-carried baskets.
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| Number | Title | Issue Date |
| 7337041 | Feedback control methods and apparatus for electro-pneumatic control systems Methods and apparatus related to feedback control for electro-pneumatic control systems are disclosed. An example electro-pneumatic control system comprises an electro-pneumatic controller and a secondary pneumatic power stage coupled to the electro-pneumatic contro... | 02/26/2008 |
| 7207173 | Method and apparatus for warm up control of autonomous inverter-driven hydraulic unit An apparatus for warm up control of an autonomous inverter-driven hydraulic unit has a warm up control section and a switch section. The warm up control section performs a predetermined process using a current speed and current pressure as input information and outp... | 04/24/2007 |
| 7159506 | State detecting device for load element receiving load of working fluid and state detecting device for fluid pressure control circuit The load element state detecting portion 72 detects the completion of the filling of the hydraulic oil into the clutch 62 and the working limit of the accumulator 64 on the basis of the displacement of the spool valve element 42. That is,... | 01/09/2007 |
| 7134668 | Differential pumping seal apparatus A differential pumping seal apparatus includes a differential pumping seal for sealing a first space and a second space from each other in a non-contact manner, and a back up seal mechanism for sealing the first space and the second space from each other in a contac... | 11/14/2006 |
| 7096772 | System and method for controlling hydraulic fluid flow A method of flowing hydraulic fluid in a work machine is disclosed. The method includes generating a control signal from an input mechanism and generating a property signal indicative of a viscosity of the hydraulic fluid. The control signal and the property signal ... | 08/29/2006 |
| 6415604 | Hydraulic control circuit for work machine The invention relates to a hydraulic control circuit that allows operation to continue, when the working portion approaches the cab during work, and allows the working portion to stop when the working portion reaches the limit position, whereby the workin... | 07/09/2002 |
| 6397590 | Hydraulic warming system for use in low ambient temperature applications A hydraulic warming system for low ambient temperature (0° to -65° F.) operation includes a hydraulic motor integrated in a valve manifold and driven by a two-stage jet pipe flow control electro-hydraulic servovalve mounted on the valve manifold in prox... | 06/04/2002 |
| 6382076 | Piston servo-actuation main system with hydromechanically self-contained detection Main piston servo-actuation system, with hydromechanic self-contained failure detection device, working with hydraulic fluid supplied by a pump, including two servovalves (1 and 2) which are identical in design, controlling a piston (3) mechanically linke... | 05/07/2002 |
| 6253859 | Lifting device for the lower steering arms of an attaching device of a tractor A lifting device for lower steering arms of a tractor has a position recording device (25). The position recording device (25) generates a position signal representing the pivot position of the lower steering arms (2, 3). A piston-cylinder unit (11, 12) a... | 07/03/2001 |
| 6230090 | Interference prevention system for two-piece boom type hydraulic excavator When an arm end exceeds a boundary line K2 and enters a slowdown area R1, a proportional solenoid pressure reducing valve 13 is operated to reduce a pilot pressure for slowing down a first boom cylinder 1A, thereby slowing down an arm end speed. When the ... | 05/08/2001 |
| 5974800 | Device for actuating a hydrostatic drive A device for the operation of a hydrostatic drive (1) having a periodically operable switch valve (2) which connects a resonant pipe (4) connected with the hydrostatic drive (1) for the formation of standing pressure waves in the hydraulic fluid under res... | 11/02/1999 |
| 5743165 | Method for controlling driving of a ram of a hydraulic cylinder of a hydraulic press equipment It is possible for the present invention to operate with the optimal control to prevent a ram from overshooting in a case that a load acting on the ram is decreasing rapidly, like a stamping machining process. Linking a hydraulic circuit which consists of... | 04/28/1998 |
| 5564274 | Cold oil protection circuit for a hydraulic system A cold fluid protection circuit is provided for controlling the rate of fluid flow in a hydraulic system in response to the temperature of the oil in a reservoir. The subject invention includes a temperature sensor operative to sense the temperature of th... | 10/15/1996 |
| 5464085 | Solenoid operated hydraulic valve A solenoid operated hydraulic valve for supplying a regulated hydraulic pressure to a load in dependence upon an electrical demand signal applied to the valve. The valve is operable to sense the temperature of the hydraulic fluid flowing through the valve... | 11/07/1995 |
| 5398794 | Overheating protection device for rotational control apparatus A device (110) for protecting a clutch (C) against overheating from externally caused problems such as rapid cycling is disclosed including a heat conductive plug (120) sealed in an escape port (116) of a fitting (112) by fuse material (124) such as lead.... | 03/21/1995 |
| 5361680 | Pressure-intensifying type fluid pressure cylinder In a pressure-intensifying type fluid pressure cylinder, an auxiliary cylinder chamber is provided outside a rod cover, a pressure intensifying piston is axially and slidably disposed on the outer peripheral portion of a piston rod in the auxiliary cylind... | 11/08/1994 |
| 5218820 | Hydraulic control system with pressure responsive rate control A hydraulic control system for controlling the motion of a double acting hydraulic actuator determines the flow to and from the actuator in accordance with 1. the desired movement of the actuator 2. the measured hydraulic pressures on opposite sides of the pis... | 06/15/1993 |
| 5218896 | Driving mechanism with gas bearing A driving mechanism usable in an electron beam exposure apparatus, X-ray exposure apparatus, ion beam exposure apparatus, evaporation apparatus, chemical vapor deposition apparatus or otherwise, for rectilinearly moving a wafer carrying stage in a vacuum ... | 06/15/1993 |
| 5150644 | Release valve mechanism in a fluid operated linear actuator for a portable cutter or the like A single acting, spring return hydraulic cylinder suitable for use as an actuator of a portable cutter or the like. A piston slidably received in the cylinder has formed therein a hollow and a hole communicating the follow with a fluid chamber on one side... | 09/29/1992 |
| 4899785 | Proportional pressure reducing valve In a proportional pressure reducing valve including a spool having a first end connected to a solenoid and a second end exposed to a feedback chamber, and formed with a groove for allowing a supply port to communicate with an output port when the spool is... | 02/13/1990 |
| 4889036 | Speed reducer for pneumatic actuator A speed-reducing valve assembly is provided in an air passage through which compressed air is discharged when a pneumatic actuator is decelerated. The speed-reducing valve assembly comprises a three-way valve actuated by a signal generated when the actuat... | 12/26/1989 |
| 4870889 | Hydraulic device for fuel pumping apparatus A hydraulic device includes a piston slidable within a cylinder. Fluid under pressure is admitted to one end of the cylinder through an inlet which contains a restrictor. The piston is formed with an orifice and is biased by a first spring towards the one... | 10/03/1989 |
| 4825752 | End-of-stroke bypass valve in piston for impact relief in hydraulic tilt and trim cylinder An impact relief valve and apparatus is disclosed which includes a hydraulic pump connected by two feed lines to a hydraulic cylinder. A first feed line provides fluid below a piston of the cylinder and the second feed line provides fluid above the piston... | 05/02/1989 |
| 4798050 | Control system for hydraulic tandem pump in motor vehicle A control system for a hydraulic tandem pump assembly including a primary pump for supplying fluid under pressure to a power-assisted steering device and a secondary pump for supplying fluid under pressure to a hydraulic motor of an engine cooling fan, wh... | 01/17/1989 |
| 4776418 | Four wheel steering having closed hydraulic system with pressure control assembly A closed hydraulic system (22) is provided for transmitting steering movement to a rear wheel steering assembly (16) in response to steering movement of a front wheel steering assembly (14). The front wheel steering assembly is controlled by a steering wh... | 10/11/1988 |
| 4748893 | Drive/frame assembly for a reciprocating floor Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). ... | 06/07/1988 |
| 4748894 | Drive/frame assembly for a reciprocating floor Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). ... | 06/07/1988 |
| 4644848 | Electro-pneumatic pressure regulator for tools An electro-pneumatic pressure regulator control system for precisely adjusting the pressure of fluids applied to a fluid-powered tool such as hydraulic cylinders, pneumatic wrenches and the like includes a current-to-pressure (I/P) transducer, and a fluid... | 02/24/1987 |
| 4579206 | Fluid coupling device and valve mechanism for use therein A fluid coupling device (15) is disclosed of the type including an output coupling assembly (67) and an input coupling member (81) with a shear space (90) disposed therebetween. The coupling device includes a valve assembly (117) to control the flow of fl... | 04/01/1986 |
| 4570849 | Fan drive, particularly for cooling installation of vehicles Disclosed is a fan drive, in particular one for cooling installations of rail vehicles. The fan drive comprises a hydraulic motor and a control valve which regulates a bypass as a function of temperature, thus affecting the flow of a pressure medium drivi... | 02/18/1986 |
| 4416417 | Sterilized storage container A container lid is released at a desired point in a sterilizing cycle with the actuating movement being provided by an expandable chamber having a quantity of sterilizing environment captured during the sterilizing cycle.... | 11/22/1983 |
| 4392771 | Lift safety switch system An electrically controlled hydraulic lift, such as wheelchair lifts for vehicles, wherein the hydraulic reciprocating motor for operating the platform of the lift is mounted in a vertical slot so that any obstruction in the downward movement of the platfo... | 07/12/1983 |
| 4354351 | Load sensing steering Fluid in the relatively long lines (22, 24) between a control valve (16) and a fluid actuator (14) can become overly viscous in cold weather. Herein, fluid is circulated through such lines (22, 24), at least during cold weather, even when the fluid actuat... | 10/19/1982 |
| 4336903 | Control valve The control valve for keeping a constant temperature or viscosity of a pressure medium in a hydraulic consumer circuit includes a main control valve provided with a control slider and a preliminary control valve in which a temperature sensitive control el... | 06/29/1982 |
| 4274494 | Method and device for setting the direction and/or the inclination of an elongated rock drilling apparatus An elongated rock drilling apparatus is swingable by positioning power means. Set values of inclination and direction of the rock drilling apparatus are set by prepositioning a first pendulum device relative to the rock drilling apparatus. According to on... | 06/23/1981 |
| 4269111 | Hydraulic apparatus The hydraulic apparatus includes a valve which is closable to prevent fluid from flowing out of a cylinder chamber when the pressure of the fluid drops below a predetermined level, and a transmitter which opens the valve so as to keep the chamber pressure... | 05/26/1981 |
| 4250360 | Device to automatically activate or deactivate control means A device designed to effect automatic activation or deactivation of electrically, hydraulically or pneumatically operated control means, comprising a body freely movable in an air-tight housing and in its normal position sealing an aperture, a spring-bias... | 02/10/1981 |
| 4189919 | Motor-valve apparatus for hydraulic fan drive system A vehicle engine accessory drive system is disclosed including a hydraulic fan motor (41) and a power steering gear mechanism SG in series flow relationship. The vehicle power steering pump P is the sole source of fluid for the system and has its flow con... | 02/26/1980 |
| 4179888 | Hydraulic fan drive system A vehicle engine accessory drive system is disclosed including a hydraulic fan motor and a power steering gear mechanism in series flow relationship. The vehicle power steering pump is the sole source of fluid for the system and has its flow control setti... | 12/25/1979 |
| 4033134 | Heat engine A heat engine comprising a cylindrical heat chamber having an end wall of insulating material and on which is mounted a cylinder. An opening in the end wall communicates between the heat chamber and the cylinder. The cylinder is surrounded by a cooling ja... | 07/05/1977 |
