Abstract: A porosity measuring MWD system utilizing a source and two detectors is set forth. The source and two detectors are preferably mounted in a stabilizer fin on a drill collar. A standoff measuring device is also included. Dependent on dynamically measured standoff, output pulses from the two detectors are input to storage counters; different counters are selected for different ranges of standoff. Porosity measurements are determined from the counts for variations in standoff measurements; this provides a near/far ratio for ranges of standoff; as the standoff range varies, the counts are directed to different counters. Near/far ratios are determined and represent the apparent porosity; a corrected value of porosity is then determined for each particular range of standoff.

Abstract: A process for determining a safety margin with respect to adhesion between tires and roadway of a travelling motor vehicle comprises, detecting longitudinal and transverse acceleration values (ax, ay), a rotational wheel acceleration value (Phi), and a dynamic steering angle value, and producing signals indicative thereof. A longitudinal adhesion value (Six) is determined as a function of the longitudinal acceleration (ax) and the rotational wheel acceleration (Phi), while a transverse adhesion value (Siy) is determined as a function of the transverse acceleration (ay) and the dynamic steering angle. Maximum attainable longitudinal and transverse acceleration values (axLIM, ayLIM) are next determined by multiplying the longitudinal and transverse acceleration values (Six, Siy) by vehicle specific coefficients (Kx, Ky) and a limit curve (aLIM), e.g., an ellipse, is established.

Abstract: An apparatus and technique for determining the abrasion potential for tire treads is presented. A tire is rotatably and forcefully brought into contacting engagement with a reflective surface received upon an illuminated glass plate. A charge coupled device monitors the internal reflection light which evidences a grey level corresponding to the force of engagement between the associated portion of the tire and the glass support plate. A marker is placed upon the tire centrally within a region of interest. The video image of the marker and region of interest is analyzed as to slip and force at that area. The product of the slip and force functions is an indication of frictional work at the interface between the tire and support surface and is correspondingly an indication of the propensity of the tire to wear.

Abstract: A production functional test for hydraulic brake control and traction control units which utilizes compressed air as a test medium. Compressed air is applied to an external port of a hydraulic brake or traction control unit which includes valves, accumulators and a positive displacement pump driven by an electric motor connected by internal passageways. The air pressure at another external port is monitored while the various components are exercised according to a test sequence. The monitored pressure must be within predetermined limits at various points of the test to demonstrate that the brake control unit is functioning properly. Air flow rates and pump motor current are also measured at specific points in the test. The test method can identify incorrectly sized and installed components.

Abstract: An ultrasonic liquid level gauging sensor has a transducer at the lower end of a tube that is filled with liquid to the same height as liquid outside the tube. The sensor has an axial rod extending along the tube and supporting several calibration reflectors. The rod enables the sensor to be used at high tilt angles.

Abstract: A gravity gradiometer and method for measurement of changes in the intensity of a gravitational field experienced during traversal over earth's terrain, or past a massive object, has a set of eight accelerometers disposed on rotating disc, or on a pair of parallel discs, and arranged uniformly about a central rotational axis of the disc, or of the pair of discs. Each accelerometer develops a signal for maintaining a pendulum in its position of swing along an input axis of the accelerometer. Each input axis, for all of the accelerometers, is perpendicular or parallel to a radius of a disc. The accelerometers are treated as two groups of four accelerometers wherein, in each group, the accelerometers are disposed in pairs about perpendicular diameters of the disc or the pair of discs.

Abstract: The present invention relates to a microaccelerometer employing a single free-mass and capable of measuring acceleration along three coordinate axes, and a process for fabricating through micromachining and microelectronic techniques a microaccelerometer employing a free-mass. A microaccelerometer preform is constructed by chemically coating and etching a silicon wafer to form a support member and a free-mass surrounded by the member. The free-mass is movable with respect to, but constrained by the silicon support member. Acceleration measurements are obtained by circuits which sense changes in the position of the free-mass with respect to an equilibrium position, induced by a change in the rate of acceleration of the accelerometer, and the electromagnetic force required to restore the free-mass to its equilibrium position.

Abstract: To measure pressure acting on a support (1), a sealed bag (2) which is filled with a fluid and has flexible bag walls (9, 10), and which is arranged on the support (1) and whose interior communicates with a flexible capillary tube (4, 4'), is used as a sensor. Connected to the free end of the flexible capillary tube (4, 4') is an evaluation device which detects pressure variation, it being possible for the end of the flexible capillary tube (4, 4') to be plugged into a block (5). The block has a bore (6) which continues the channel of the flexible capillary tube (4, 4') and is sealed at its end not: subjected to the flexible capillary tube (4, 4') by a diaphragm (7). The diaphragm bulges outwards in the event of a reduction in the volume of the bag (2). The extent of the outward bulging of the diaphragm (7) can be determined by an optical detector (15, 16).

Abstract: This invention relates to a pressure measurement apparatus for inspecting therapentic energy waves, e.g. shock waves or ultrasonic waves. The pressure measurement apparatus for inspecting focal position and pressure of therapeutic energy waves comprises a pressure sensing sheet which changes visually or electrically according to the pressure, and a marker for setting the focal position, mounted on the pressure sensing sheet. Also, the apparatus for inspecting focal position and pressure of therapeutic energy waves in a water tank, comprises, a pressure sensing sheet which changes visually or electrically according to the pressure, a mount for holding the pressure sensing sheet as a flat shape, a mount holder for holding the mount, a marker for setting the focal position, held above the pressure sensing sheet from the mount holder, and holder means for holding the mount holder into the water tank.

Abstract: A capacitive differential pressure sensor comprises two end pieces and a central diaphragm all of the same type of electrically non-conductive material, such as quartz. As the central diaphragm moves relative to the end pieces in response to pressures applied through the end pieces, capacitance changes are sensed through one pair of facing electrodes on one end piece and the diaphragm and another pair of facing electrodes on the other end piece and the diaphragm. A method of measuring differential pressures at an oil or gas well with such a sensor is also disclosed.

Abstract: Microminiature pressure transducers are formed on semiconductor substrates such as silicon and include a membrane which spans a cavity over the substrate, with the membrane being mounted to and sealed to the substrate at the peripheral edges of the membrane. The bottom of the cavity forms an overpressure stop to prevent over deflections of the membrane toward the substrate. An overpressure stop formed as a bridge of a material such as nickel extends above the membrane and is spaced therefrom to allow the membrane to deflect freely under normal pressure situations but prevent over deflections. The thickness of the polysilicon membrane and the spacing between the membrane and the overpressure stops is preferably in the range of 10 micrometers or less, and typically in the range of one micrometer. The overpressure stop bridge is formed utilizing deep X-ray lithography to form a well-defined bridge structure.

Abstract: An overpressure-protected, differential pressure sensor (37) is formed by depositing diaphragm material (24) over a cavity (23) formed and filled with sacrificial material (22) into a front surface of a substrate. The sacrificial material (22) is then removed to create a free diaphragm. The floor of the cavity (23) defines a first pressure stop to limit the deflection of the diaphragm in response to pressure applied to the top of the diaphragm. A port (33) is created to allow pressure to be applied to the bottom side of the diaphragm (24). An optional second pressure stop, which limits the deflection of the diaphragm in response to pressure applied to the bottom side of the diaphragm, is formed by bonding a cap (35) to stand-offs (34) placed around the top of the diaphragm. The stand-offs are spaced to allow pressure to be applied to the top of the diaphragm.

Abstract: A method an apparatus for measuring a base condition volumetric flowrate of a pipeline gas flowing through a pipeline in which a pipeline gas flowrate is measured by a pipeline gas flowmeter; a volumetric correction ratio is derived by: measuring a sample gas flowrate of sample gas tapped from the pipeline, measuring an energy flowrate of the sample gas, measuring a heating value of the sample gas, and measuing a base condition density of the sample gas; and the base condition volumetric flowrate of the pipeline gas flowing through the pipeline is determined by adjusting the pipeline gas flowrate as measured by the pipeline gas flowmeter by the volumetric correction ratio. The temperature of the sample gas should be substantially the same as the pipeline gas in the pipeline when the sample gas flowrate is measured.

Abstract: An ultrasonic transducer includes a film of piezoelectric material mounted on the support column. Two overlapping metal foil electrodes are in intimate contact with the two opposite surfaces of the film respectively, and a respective electrical lead is connected to each electrode.

Abstract: Single tube Coriolis flowmeter with floating intermediate section including an elongated upstream inlet conduit section, an elongated downstream outlet conduit section laterally offset from the inlet conduit section, an inlet-outlet plate rigidly connecting the inlet and outlet conduit sections together at their proximate ends, and a continuous and generally helically wound length of conduit (approximately a 720-degree coil), the ends of which are respectively continuations of the inlet and outlet conduit sections. The helically wound length of conduit includes an upstream metering loop section and a downstream metering loop section joined together by a "floating", unsupported intermediate conduit section. The upstream ends of each metering loop section are coupled by a first connecting plate, while the downstream ends of each metering loop section are coupled by a second connecting plate.

Abstract: Stress in a paper web in a rotary printing press is measured by directing the web past two tubular members spaced in the direction of web travel and supported by support arms. Deflection of the support arms is measured and provides an indication of the amount of stress in the paper web.

Abstract: A pressure actuated sensor device (20) has an upper plate (21) functionally cooperating with an optical fiber (26) so that when pressure is applied onto the upper plate (21) light transmitted through the optical fiber is attenuated. The optical fiber (26) in the device (20) is sandwiched between one layer (24) made of a flexible material and a second layer (25) of rigid wires.

Abstract: A method of detecting engagement/disengagement characteristics of a less-force required type mating connector, and apparatus therefor. In the less-force required type mating connector, a lever provided in a first connector is pivoted to engage or disengage a second connector with or from the first connector. The first connector is pivoted about a center of pivotal movement of the lever while the pivotal movement of the lever is prevented. A load required to prevent the pivotal movement of the lever is detected. Since the lever is unchanged in its position and angle, the load acting in one direction alone may be detected. Hence, the engagement/disengagement characteristics can be accurately detected.

Abstract: A gauge assembly (10) utilizing a voltage divider circuit to provide reliable and accurate measurement of a fluid level within a tank (16) or other environment. A pointer assembly (52) pivots about an axis (42) in response to a moving float to indicate the fluid level. A plurality of contact arms (114, 116, 118) extending from a contact plate (58) on the pointer assembly (52) resiliently engage a point (120) along a resistive element (88). The first end of the resistive element is connected to a voltage regulator (100) which is connected to a first contact (94). The second end of the resistive element forms a second contact (96). The point (120) of contact between the contact arms and resistive element is connected to an amplifier (102) which is connected to a third contact (95) forming a low impedance voltage divider circuit.

Abstract: An impact sensing apparatus includes a housing having a wall portion which is parallel with the applied direction of an outside shock and a hole which is formed in the wall portion, a weight disposed in the housing and moved by an outside shock which is more than a predetermined value, an output member rotatably disposed in the housing and rotated in response to the movement of the weight and an urging member interposed between the housing and the output member for urging the output member so as to project from the hole. According to this improved impact sensing apparatus, it is possible to lengthen the stroke of the rotational motion of the output member and therefore it is possible to effectively utilize the urging force of the urging member as a kinetic energy of the output member. Thus, it is possible to improve the reliability for igniting the ignition element such as a primer due to a striking operation of the output member.

Abstract: A three axis, single degree of freedom gyroscope based rate sensing platform has restraining torque developed for the platform from a feedback loop that includes electronics that decouples individual gyroscope outputs from the rate inputs that correspond to axes other than the input axis for that gyroscope and provides an enhanced frequency response. The outputs from the various gyroscopes are processed in a compensator that estimates the platform rates on independent axes using either a Kalman filter estimator or a matrix inverse of the matrix equation of motion between platform input rate and gyroscope output. High bandwidth performance is obtained by an increased stiffness and prefiltering of the gyro torque inputs.

Abstract: An adapter for manual attachment and removal of a flanged motor on a power driven appliance. A bracket attaches to the appliance and cooperatively receives the motor flange. Pins incorporating clips or expanding projections then secure the motor to the appliance. A shaft-to-shaft connector is then secured by similar pins, thus coupling the motor output shaft and appliance power input shaft. For belt driven appliances, the motor output shaft terminates in a pulley, or is coupled to a shaft having a pulley and attached to the appliance. Optionally, a belt tensioning pulley is included.

Abstract: The present invention provides a drive apparatus that is compact in size, low in cost, allows the attaining of a high degree of accuracy as well as high-speed driving, and suppresses the production of noise.The present invention is composed so that a drive roller rolls along a track rail as a result of providing a torque generation device on a slider guided by said track rail, and attaching the output shaft of said torque generation device to said drive roller.

Abstract: In a linkage through which a manual selector is connected to a manual valve are a power unit and a connecting/disconnecting mechanism. In "P", "R", and "N", the connecting/disconnecting mechanism is connected and the power unit is made inoperative, whereby a movement of the manual selector is mechanically transmitted directly to the manual valve. In other shifts including manual shifts, the connecting/disconnecting mechanism is disconnected and the manual valve is operated directly by the power unit in accordance with positions of the selector lever.

Abstract: A countershaft transmission and control has an input shaft, two countershafts and an output differential. Each countershaft has a fluid operated clutch connected therewith to selectively connect the respective countershaft with the output differential through reduction gearing. A plurality of drive and driven gear members are connected in meshing relation between the input shaft and the countershafts. Individually operable synchronizers are disposed on the countershafts to selectively engage the driven gears with the countershaft to establish gear ratios between the input shaft and the output differential. The synchronizers are operated by a control mechanism comprised of drive keys for selectively connecting synchronizer forks with a longitudinally movable shaft member. The control mechanism is also operable to provide a positive displacement pump assembly operated by the shaft member to deliver pressurized fluid to the clutch member for enforcing engagement thereof.

Abstract: An X-Y shifting mechanism (25) is disclosed for controlling the shifting of a shift rail (17) in a first (Y-Y) transverse direction. The mechanism includes a shift finger assembly (39) including a shift finger (23). A lever member (57) is pivotable about the axis (A) of rotation. When the lever member (57) is pivoted, the movement is transmitted through a spring (91) to rotate a spring seat member (73), thus causing pivotal movement of the shift finger (23). During a non-synchronous engagement, kick-out movement causes pivotal movement of the shift finger in the opposite direction, compressing the spring (91) rather than damaging the shifting mechanism. The disclosed mechanism also enables preselection of neutral, compressing the appropriate one of the springs (91), such that the preloaded spring will move the shift finger and shift rail to the neutral position as soon as a torque break occurs.

Abstract: The present invention gearshift assembly for a motorized vehicle manual transmission comprises a gearshift lever having an upper ball which determines a crossover pivot ratio and a lower ball which determines a different linear pivot ratio. Also, a uniquely shaped socket transfers the upper ball's crossover movement and the lower ball's linear movement to the attached shift rail. The socket has a pair of lateral walls, a short forward facing wall, a short rearward facing wall, and a cavity therewithin.

Abstract: The industrial robot comprises two lower arms arranged parallel to each other and pivotably supported on a lower base member; an upper base member pivotably mounted on upper ends of these two lower arms, respectively so as to form a parallelogram together with the two lower arms; at least one first driving source for driving the parallelogrammic link; an upper arm pivotably supported on one side of the upper base member so as not to interfere with the parallelogrammic link and driven by a second driving source. Since the upper arm can be moved horizontally by inclination motion of the parallelogrammic link mechanism and further the upper arm is pivoted on one side of the upper base, the upper arm can be moved frontward, rearward and upward without any interference with the lower arms.

Abstract: An actuator device of particular use in changing the configuration of a deformable mirror faceplate includes an electrically deformable actuator confined between a grounded electrode disposed on a front surface of a support and an end cap of a tensioning unit which further includes an elongated tensioning element secured to the end cap and passing through a central opening of the actuator and a passage in the support with a free end portion thereof extending beyond the other surface of the support. A tensioning assembly for imposing a preloading force on the actuator includes an externally threaded sleeve surrounding and secured to the free end portion of the tensioning element, and an internally threaded nut meshing with the sleeve and acting on the support.

Abstract: An adjustable handlebar apparatus for support on a bicycle frame. The handlebar apparatus includes a base member clamped to the bicycle frame, a rocker member disposed on the base frame and pivotally supported from the base member, and a handlebar assembly. The handlebar assembly includes a handlebar attached to a slide member. This slide member interlocks in different longitudinally disposed positions in the rocker member.

Abstract: A cam assembly and method for providing a substantially constant load to a motor that drives the cam assembly. A torque compensated cam assembly (142,300) includes a plurality of tracks (140,150,152/310,312,314) that are profiled with a surface that varies radially as the cam rotates, thereby actuating cam followers, each of which rolls along a different track. A tangential force developed by the cam followers as they move over rapid radial changes in the surfaces of the tracks produces a total net torque that at times tends to aid the rotation of the cam and at times tends to impede its rotation. The cam is used in a volumetric pump (30) that accurately delivers a desired volume of fluid at a desire rate. To assist in maintaining the accuracy of these parameters, the torque compensated cam assembly presents a substantially constant load to a motor (146,304) that drives the cam.

Abstract: A fluid operated tool for tightening and loosening an element has a unit for clamping an element to be tightened or loosened, a unit for turning the element clamped by the clamping unit, and a fluid operated drive unit formed to act on the clamping unit and on the turning unit so that under the action of the fluid operated drive unit the clamping unit clamp the element and then the turning unit turn the clamped element.

Abstract: Pliers having opposed gripping tips thereon wherein each gripping tip is figured as a tooth which extends toward the opposite gripping tip.

Abstract: A cable cutting apparatus incorporating a mechanism for preventing the erroneous cutting of the cables in use, which is both inexpensive and simple. This cable cutting apparatus includes a cutting mechanism having cutting blades for cutting a cable; a core potential recognition unit for recognizing a potential of the cutting blades brought into contact with a core of the cable as one of a potential for a cable in use and a potential for a cable out of use; and a locking mechanism for locking cutting movements of the cutting blades of the cutting mechanism whenever the core potential recognition unit recognizes the potential of the cutting blades in contact with the core of the cable as the potential for a cable in use.

Abstract: A crosscutting device for a folder assembly utilizes a pair of cooperating cylinders. A cutting groove cylinder has at least one groove strip assembly on its periphery and cooperates with a cutter cylinder having a corresponding number of cutters. Each groove strip assembly includes a cutting groove component and a pressure spring component.

Abstract: A web feed device, particularly a tractor for feeding perforated paper, is provided with the capability of automatically cutting a margin along the edge of the paper. Where this margin is defined by side perforations, the apparatus is operative to burst the perforations automatically. The tractor has a lid which is spring biased in a closed position spaced from a surface of the frame of the tractor over which the paper is driven, as by a belt having pins which are received in feed perforations along the margin between the side perforations and the edge where the belt is entrained around a sprocket which drives the belt. The mechanism has a lower cutting disk, driven with the sprocket and presenting a cutting edge along an outside surface.

Abstract: The pressure-retaining device or clamp acts on the roll or log adjacently to the cutting plane and may be adapted to various diameters of the material being processed; for each path of advance of the rolls or logs (B) and on each side of the cutting plane, it comprises: a pair of symmetrically curved flexible strips (12, 14) projecting from enclosing supports (9A, 10; 7A, 10) and having end portions able to move according to the variation in the diameter of the roll, and a strap (22) fixed to elastic return holders (24A) and adjusting holders, said strap surrounding the pair of strips (12, 14) so as to vary their geometry in relation to the variation in the diameter of the material being processed.

Abstract: A miter saw includes a base for placing a work thereon and a miter saw unit supported by a support mechanism relative to the base. The miter saw unit supports a saw blade and a motor for driving the saw blade. The motor has a motor shaft extending in a longitudinal direction of the motor. A transmission mechanism serves to transmit rotation of the motor to the saw blade. The support mechanism supports the miter saw unit in such a manner that the miter saw unit is vertically pivotable and that the miter saw unit is laterally pivotable from a vertical position to an inclined position. The rotational axis of the saw blade extends substantially horizontally when the miter saw unit is at the vertical position, and the rotational axis of the saw blade extends obliquely relative to the horizontal direction when the miter saw unit is at the inclined position. The motor is positioned on one lateral side of the miter saw unit toward the inclined position.

Abstract: A ball lock punch and die retainer comprises a single piece body of high strength through hardened tool steel having a relieved flat bottomed borehole for the punch. The exterior sidewall of the retainer opposite the end having the punch borehole is substantially half-cylindrical.

Abstract: The present invention relates to a device for retaining knife blades for cutting, perforation or other treatment of a running web, preferably a paper web. The web runs between a rotatable knife-retaining cylinder and a counter pressure cylinder, whereby the knife blade may be wedged up by a wedge device by being brought into the slot by the counter pressure cylinder. In order to permit effective wedging up of knife blades in exact positions in the slot, even when the blades have dimensions which differ from knife blades of the certain defined dimension, the wedge device comprises and/or cooperates with at least one spring disposed beside the wedge device in the slot, upon insertion of a knife blade into the slot for wedging up thereof by the counter pressure cylinder.

Abstract: A woodwind mouthpiece is disclosed that has a straight-through air passageway that produces richer and brighter tones while minimizing restrictive flow, turbulence and back pressure in the mouthpiece. The arrangement of the walls in selected planes, the position of the top wall with respect to the reed-supporting surface and the lay angle of the reed-supporting surface allow the instrument associated with the mouthpiece to be played in a variety of positions. Different lay angles can be designed into the mouthpiece. Other features are disclosed.

Abstract: In construction of a drum in which at least one open end of a cylindrical drum shell is closed by a drum head which is held in tension by assistance of a fastening element such as a suspension ring, opposite fastening elements are connected to each other by long tubes which are directly and mechanically connected to the drum shell. Not only the long tubes but also the drum shell shares mechanical load generated by tensioning of the drum head so as to elongate the life of the long tubes.

Abstract: A solid braid structure comprising a plurality of interlocked layers is created by causing a plurality of package carriers of yarn to move along a plurality of defined serpentine paths by track modules. The track modules extend in a first direction to define a longitudinally extending path corresponding to a first layer of the braid structure and in a second direction to provide at least one crossover path between adjacent serpentine paths. The package carriers which move in the first direction create a first layer of braid and, at a crossover path, move between adjacent serpentine paths to cause the yarn forming the first layer of braid to interlock with the braid of an adjacent layer.

Abstract: A resettable bore obstruction detector indicator is positioned on the muz end of a gun bore to indicate whether the gun bore is free from obstruction after a round has been loaded.

Abstract: A projectile launcher and in particular a mass/countermass projectile launcher in which the piston intercept(s) comprises a braking collar (8) made of a material which exhibits constrained progressive crushing. When a projectile (18) is fired the launching piston (10) impacts upon the braking collar (8) at the muzzle of the launcher and initiates constrained progressive crushing in the collar (8). The crushing of the collar (8) absorbs the kinetic energy of the piston (10) thus arresting the axial motion of the piston (10). The projectile launcher according to the present invention can be less massive than similar launchers that use conventional metal piston intercepts which is an advantage if the launcher is designed to be shoulder-launched by a human operator. The type of collar material preferably used is made of a solid filler embedded in a plastics matrix and in particular the solid filler is made of reinforcing fibers.

Abstract: A recoil reducing device for use with firearms including handguns and rifles which includes a core and a sleeve that surrounds the core. The core and the sleeve each have a plurality of radially directed openings along their lengths that are cooperatively aligned with respect to each other. The openings are oriented with respect to a central bore of the core such that combustion gases generated by firing the firearm, noise and any unburnt gunpowder are directed away from a shooter, and recoil and muzzle rise of a firearm are substantially reduced.

Abstract: A radial cylinder hydraulic pump or motor has radial pistons each provided with a guide pad urged against the cylindrical inner surface of a guide element. A continuous series of rollers cover the cylindrical inner surface and are interposed between such surface and the guide pads. The rollers are prevented from coming in contact with each other by a number of auxiliary smaller rollers. Between each piston and its respective guide pad there is interposed a sliding member which is slidably mounted on the pad along a tangential direction.

Abstract: A run-up control for the pressure cheek in a drawing apparatus achieves stoppage times during the run-up phase by having a pressure cylinder with first and second pressure spaces as well as a control piston which is fixed in its position in the control cylinder when the second pressure space is acted upon with pressure. The control piston is fixed in its position by a piston rod, a fixed stop and an adjustable stop. The first pressure space is in a continuous flow connection with a mash pressure space which is reduced when the pressure cheek runs up so that the volume of the second pressure space determines the point in time of the stoppage time in the run-up phase of the pressure cheek.

Abstract: A steering system for a vehicle includes a hydraulic control valve with first and second coaxial valve members rotatable relative to each other to selectively port pressurized fluid to a vehicle power steering motor. The first valve member is connected to and rotatable with an input shaft. The second valve member is connected to and rotatable with an output member. The second valve member is axially movable relative to the first valve member between first and second positions. The input shaft and the output member are directly interconnected by the second valve member and rotatable together to effect manual steering of the vehicle when the second valve member is in its first axial position. The input shaft is rotatable relative to the output member to effect power assisted steering of the vehicle when the second valve member is in its second axial position. The second valve member is moved from its first position to its second position when the velocity of the vehicle is below a predetermined value.

Abstract: A tandem brake booster ( 12 ) having a flow path ( 145 ) between a control valve (118) and a solenoid valve (180) connected to a source of vacuum and the surrounding environment. The flow path (145) is created by first (140) and second (150) telescoping sleeves that are resiliently urged into sealing engagement with a front shell (58) and hub member (92) by a return spring (164).