Abstract: A hydrostatic bearing apparatus comprises a base member having a static pressure guide surface to which a static pressure pocket is formed, a temperature detector for detecting a temperature of an operation oil in the static pressure pocket at an outlet portion thereof and generating a signal representing the detected outlet temperature of the operation oil, a temperature controller for controlling a temperature of the operation oil to be supplied in the static pressure pocket in response to the signal from the temperature detector, and a pressure controller for controlling a pressure in the static pressure pocket by controlling a flow rate of the operation oil supplied to the static pressure pocket. An operation oil source storing the operation oil to be supplied to the static pressure pocket is further disposed.

Abstract: A static pressure slide unit includes a guide rail, two-part slider slidably mounted on the guide rail and having a slider main body and a slider pressure member, and a mechanism interposed between the slider main body and the slider pressure member for constantly urging the slider pressure member against the guide rail. A pressurized fluid supplying system is also provided for supplying a gas or liquid under pressure to a sliding contact interface between the guide rail and the slider.

Abstract: A stiffener assembly which provides for improved performance of a movable stage arrangement. Often, it is desired to provide a movable stage arrangement in which a stage moves linearly with respect to a stationary base. In many applications, it is necessary for the stage to move to successive rest positions, with movement of the stage inhibited at each of the reset positions. The stiffener of the present invention allows for controlled movement of a stage along its direction of travel, with the stiffener inhibiting undesired movement when the stage is at a rest position. In one form, a stiffener extends in the direction of travel of the stage, with one end of the stiffener assembly mounted to the stationary base, and the other end urged into frictional contact with the movable stage by a force applicator. As a result, the stiffener is placed in frictional contact with the movable stage.

Abstract: A linear motion rolling contact guide unit includes a rail, a slider assembly and a plurality of rolling members interposed between the rail and the slider assembly. The slider assembly includes a pair of lower and upper sub-assemblies. The lower sub-assembly is slidably mounted on the rail and the upper sub-assembly is mounted on the lower sub-assembly such that it may move transversely relative to the lower sub-assembly over a limited distance. A low friction intermediate member is provided at a first location in a gap between the opposed surfaces of the upper and lower sub-assemblies so as to provide an enhanced sliding characteristic therebetween. A squeeze film damper mechanism is provided at a second location in the gap between the upper and lower sub-assemblies for damping and/or absorbing undesired motion.

Abstract: A linear motion rolling contact guide unit includes a rail having a horizontally extending wing section, a slider slidably mounted on the rail and a plurality of rollers interposed between the top surface of the rail and the slider so as to allow a shift in position in a lateral direction between the rail and the slider as the slider moves along the rail. A first slide member is fixedly attached to the slider to define a first squeeze film damper between the top surface of the rail and the first slide member. A second slide member is fixedly attached to the slider to define a second squeeze film damper between the bottom surface of the wing section and the second slide member. Each of the first and second squeeze film dampers includes an oil film for damping or absorbing any undesired vibratory motion.

Abstract: A ball screw driven linear motion rolling contact guide unit includes a rail having a generally U-shaped cross section and a ball screw shaft and a slider received in the rail and operatively coupled to the ball screw shaft. A plurality of rolling members are interposed between the slider and the rail. The rail has a bottom wall formed with a trench in which a quantity of damping oil is reserved. The slider is provided with a projection which projects into the trench to thereby define a squeeze film damper mechanism. The slider is also provided with an endless circulating path, including a load path section, a return path section and a pair of curved connecting path sections, each connecting the corresponding ends of the load and return path sections, whereby the return path section is located lower in level than the load path section.

Abstract: A linear motion guide unit includes a rail having a top surface, a bottom surface and a pair of side surfaces, a thin plate member fixedly attached to the top surface of the rail and a slider slidably mounted on the rail with a predetermined gap between the thin plate member and the slider such that a film of oil may be formed for damping or absorbing any vibration. The thin plate member is preferably formed with an oil groove for storing therein a quantity of oil.

Abstract: A sliding contact type linear motion guide unit having at least one of desired anti-vibration and braking functions is provided. The unit includes a rail extending over a desired length, a slider movably mounted on the rail and a sliding member interposed between the rail and the slider. The sliding member includes an elastic member fixedly attached to the slider and a contact member fixedly attached to the elastic member and having a contact surface in sliding contact with the rail. In the preferred embodiment, the elastic member includes an elastic enclosure having therein a fill, such as a gas, liquid or gel, under pressure, so that the contact pressure between the contact member and the rail can be maintained substantially unchanged and uniformly. A control valve is preferably provided in communication with the interior of the enclosure.

Abstract: A ball screw assembly includes a screw shaft hving a peripheral surface formed with a spiral groove, an outer sleeve fitted onto the screw shaft with a predetermined gap therebetween and a plurality of balls interposed between the screw shaft and the outer sleeve. A ball holder is provided in a radial hole formed in the outer sleeve and a ball is rotatably held in position and in engagement with the spiral groove by the ball holder. A fluid line is formed in the outer sleeve and the ball holder so that a pressuerized fluid may be supplied to establish a fluidic cushion between the ball holder and the ball. Also provided is a plurality of solid lubricants which are preferably arranged alternately with the balls and normally pressed against the spiral groove to keep the groove lubricated at all times.

Abstract: In a rolling bearing for linear movements, two rolling member circuits arranged between one arm of a U-shaped guide carriage and a lateral face of a guide rail, are substantially perpendicular to one another with their force transmission planes and are substantially parallel to one another with their circuit planes. All rollers have parallel axes in each of the two roller circuits. The load-transmitting row of rollers and the return row of rollers are offset from one another in the axial direction of the rollers in both roller circuits.

Abstract: A linear guide apparatus has a fall-off prevention and a clamp device built therein. The fall-off prevention and clamp device includes a piston and a top integrally secured to the end of a piston rod. The piston having a piston head is accommodated in an inner bore serving as a fluid pressure cylinder formed vertically in a slider. The top engages a T-shaped groove formed in a guide rail and extending axially over the whole length thereof. A belleville spring normally urges the piston head toward the guide rail, that is, in a non-clamp direction to move the top away from the inner surface of a neck portion of the T-shaped groove. When a fluid pressure is applied to the piston head at the piston rod side against the belleville spring, the piston together with the top moves away from the guide rail, that is, in a clamp direction to bring the top into engagement with the inner surface of the neck portion of the T-shaped groove. As a result, the slider is clamped to the guide rail.

Abstract: A magnetic sensor bearing utilizes an adaptive threshold circuit for signal processing in order to compensate for external factors such as temperature, stress, aging, and external magnetic fields which all affect a fixed reference signal used with a comparator. As the magnetic sensor's output signal drifts due to these external factors, the adaptive threshold circuit causes the reference signals to drift in a complementary manner so that the magnetic sensor bearing continues to function properly in spite of the external factors.

Abstract: A low-friction slide apparatus for use with the translation stage of an optical disc recording/playback system is disclosed. The apparatus includes a rail which is fixed in position. The rail includes porous strips affixed to two orthogonal sides along its longitudinal dimension. A plurality of passages between the rail and the porous strips permits air to be forced outwardly through the pores of the strip material. The slide member, which is movably mounted on the rail, has bearing surfaces adjacent the porous strips attached to the rail. Permanent magnets mounted along these bearing surfaces maintain an attractive force between the slide and the rail, countering the force direction of the air flow, thus providing a low-friction bearing film of compressed air. A linear motor included in the rail and slide member induces motion of the slide along the rail.

Abstract: Provides new magnetic fluid bearings and magnetic fluid seals incorporating a pressure responsive system for automatically controlling the supply of magnetic fluid to the magnetic fluid feed area of such bearing or seal. The system for controlling the supply of magnetic fluid includes a reservoir of magnetic fluid and a conduit leading from the reservoir to the magnetic fluid feed area of the magnetic fluid bearing or magnetic fluid seal. A portion of the conduit is subjected to a magnetic field which establishes a pressure responsive magnetic fluid plug in that portion of the conduit to automatically control the flow of magnetic fluid to and from the reservoir as a function of the difference in pressure between the magnetic fluid feed area of the bearing or seal and the reservoir.

Abstract: An improved system for guiding one part relative another in an accurately defined path, both planar and linear, is disclosed. The improved system eliminates friction associated with heretofore moving parts, is characterized by simplicity and cost effectiveness, and comprises a first part having a primary reference surface prepared to close tolerances and accurately defining a predetermined path and an opposed parallel secondary surface, and a second part designed for guidance by the primary surface. A fixed air pad is adjustably mounted on the second part adjacent the primary surface. A second air pad is resiliently mounted on the second part adjacent the opposed secondary surface. The resilient mounting includes a bellows.

Abstract: A guiding apparatus having a slider supported in a floating manner above a base by means of hydrostatic bearings, a pressurized fluid supplying means for supplying the hydrostatic bearings with a pressurized fluid, and detecting means for detecting the displacement of the slider with respect to a designated coordinate. The pressure of the pressurized fluid from the pressurized fluid supplying means is adjusted in accordance with a signal which is obtained as a result of the comparison between the value representing the reference position of the slider with respect to the base and the value actually measured by the detecting means, thereby adjusting the sizes of the gaps for forming hydrostatic fluid film for the hydrostatic bearings, thereby to correct the position of the slider to the designated position. With this arrangement, the absolute position of the slider is precisely determined without being affected by disturbance factors such as the precision of assembling of the base and the slider.