Abstract: An apparatus for preparing NC data is used in machining an involute curve on a workpiece by relatively moving a tool and the workpiece along mutually perpendicular first and second axes encompassed within a plane while relatively rotating the tool and the workpiece about a third axis which is perpendicular to the plane. In the apparatus, there is provided involute curve definition devie defines the involute curve based upon input parameters, machining point calculation means calculates a series of machining points on the involute curve, and tangential line calculation device calculates a tangential line which connects the involute curve at each of the machining points.

Abstract: A numerically controlled grinding machine of the present invention grinds a cylindrical surface of a workpiece by a relative movement between the workpiece and a grinding wheel. The grinding conditions such as a grinding method and a finishing diameter of the workpiece are inputted so that data necessary for grinding the Workpiece are automatically determined in dependence upon the grinding conditions. The automatically determined grinding data are displayed on a display means. The grinding data displayed on the display means are modified by one of the four rules of arithmetic. The modification are carried out in accordance with a compensation rate set by override switch and the like or a compensation value inputted by a key operation.

Abstract: A hydraulic power steering system includes a pump, a flow control valve, and a bypass control valve. The flow control valve responds to a pressure drop across a metering orifice disposed in a fluid supply passage so as to control the flow rate of operating fluid by bypassing a part of the operating fluid to a reservoir. A spring chamber of the flow control valve is connected to the supply passage through a control orifice. The bypass control valve is disposed between the spring chamber and the reservoir so as to increase the amount of bypassed fluid by controlling the pressure in the spring chamber. The bypass control valve has a control spool, a load pressure introduction port connected to the upstream side of the control orifice for leading the load pressure to a first end of the control spool and a pilot port connected to the downstream side of the control orifice for leading the pressure in the spring chamber of the flow control valve to a second end of the control spool.

Abstract: In a grinding method wherein a rotating workpiece and a rotating grinding wheel are relatively moved toward and away from each other and wherein at least three of rough, fine and finish grinding step are performed successively at high, medium and low infeed rates respectively for grinding the workpiece, the grinding wheel is retracted to a back-off position at the end of the rough grinding step.

Abstract: A numerical controlled grinding machine for grinding a workpiece, in which a thermal displacement taking place between a wheel head and the workpiece, is detected with the workpiece not being subjected to the bending due to a grinding resistance. The thermal displacement is calculated from the difference between the present position of the wheel head detected by a position detector and the theoretical position thereof converted from the diameter of the workpiece measured by an in-process measuring device. The position data for the wheel head stored in a numerical controller is compensated for the calculated thermal displacement for use in the subsequent control of feed movement between the workpiece and the wheel head.

Abstract: A power steering apparatus including an electric motor for operating a hydraulic pump which supplies pressurized fluid, a directional control valve of center-closed type operable by a steering wheel for delivering the pressurized fluid supplied by the hydraulic pump selectively to a pair of cylinder chambers of a power cylinder through a supply passage, and motor controller for controlling the electric motor. While the steering wheel is at its neutral position, the controller drives the electric motor intermittently at such a low speed that does not deteriorate the efficiency of said electric motor so much so that differential pressure between a pressure at the supply passage and a higher one of pressures in the pair of cylinder chambers is returned to a predetermined first value.

Abstract: A robot controller for an articulated robot, in which a joint angle vector indicating target joint angles of respective joints of the robot is calculated based on a target position matrix indicating a desired target position, and the robot is controlled ill accordance with the joint angle vector. The robot controller is further provided with a neural network for compensating the target position so as to reduce the positioning error. The learning operation of the neural network is repeatedly carried out at predetermined intervals during the operation of the robot. The target position may be preliminarily compensated using a mathematical model.

Abstract: A power steering apparatus comprises a fluid source for supplying pressurized fluid, a power cylinder having a pair of fluid chambers, a control valve, and a drain control mechanism. The control valve is composed of first and second control portions. The first control portion has four paths connecting the fluid source and the reservoir, and each of the four paths is formed with a variable orifice of center-open type. The second control portion has two supply paths communicating the fluid source with the fluid chambers of the power cylinder, each of the supply paths being formed with a variable orifice of center-open type, and two drain paths communicating the fluid chambers with the reservoir, each of the drain paths being formed with a variable orifice of center-closed type.

Abstract: A grinding wheel for grinding a workpiece has a first grinding surface and a second grinding surface successive thereto. The first and second grinding surfaces are parallel to and inclined with respect to the rotational axis of the workpiece, respectively. A diameter of the workpiece to be ground in a next grinding operation is measured in advance. An angle to be formed between the second grinding surface and the rotational axis of the workpiece is selected based upon the measured diameter of the workpiece. The selected angle is established between the second grinding surface and the rotational axis of the workpiece. The grinding wheel is moved relative to the workpiece in a direction of the rotational axis of the workpiece, whereby the cylindrical surface of the workpiece is firstly ground by the second grinding surface and subsequently ground by the first grinding surface of the grinding wheel.

Abstract: A power steering apparatus having a fluid source for discharging pressurized fluid, a power cylinder, a control valve responsive to operation of a steering wheel for supplying the power cylinder with pressurized fluid from the fluid source, and a reservoir. The control valve has a first control portion for controlling the flow of pressurized fluid from the fluid source to the reservoir, and a second control portion for controlling the flow of pressurized fluid to the power cylinder. The first control portion has two paths connecting the fluid source and the reservoir, each of the paths being formed with at least one variable orifice of a center-open type which opens when the control valve is in a neutral state.

Abstract: A pressurized fluid supply hose which conducts pressurized fluid discharged from a pump to a fluidically operated device is disclosed. A spiral tube formed by two spirally wound band members is fixed by caulking in one end of a steel pipe. The outer shape of the one end of the steel pipe includes a taper portion formed to slope gradually between a thin portion and an outer diameter portion. By effecting a caulking process with a caulking tool having a pressing portion extending in parallel to an outer surface of the steel pipe, the outer taper portion of the steel pipe is contracted to formed an inner taper portion at an internal surface thereof, and one end of the spiral tube is fixed to the inner taper portion. Because the spiral tube is gradually deformed along the inner taper portion of the steel pipe, it can avoided that a large clearance is formed between the two band members of the spiral tube.

Abstract: In a grinding wheel for use in a grinding machine, a plurality of grinding tips are bonded on the outer peripheral surface of a wheel core having a disk-like shape by bond. On both side surfaces of the wheel core are formed with depressions continuous with the outer peripheral surface of the wheel core. Bond is filled between the outer peripheral surface and the grinding chips, and filled in the depressions of the wheel core to form a bonding layer. Namely, the bonding layer has side portions which extends along both side surfaces of the wheel core in a radial direction.

Abstract: A programming device for preparing a sequence control program to be executed by a programmable sequence controller comprises designation means for designating input and output (I/O) elements specified in the sequence control program which are to be fixed to ON or OFF states regardless of the actual ON or OFF states of the designated I/O elements, fixed I/O element converting means for converting the address of each of the I/O elements designated to be fixed by the designation means into either a memory storing address ON-state or another memory address storing OFF-state so as thereby to prepare a modified sequence control program, and loading means for loading the modified sequence control program to the programmable sequence controller being connected to the programming device.

Abstract: An apparatus for detecting contact between a contact detection member and a rotating body such as a grinding wheel rotably carried on a wheel head which is movable toward the contact detection member in a grinding machine for example. The apparatus comprises an AE sensor, a rectangular pulse generator, a sampling circuit and a processing device such as a microcomputer. The AE sensor generates an electric signal in response to vibration of the contact detection member. The rectangular pulse generator outputs a rectangular pulse whose duration corresponds to that of vibration. The sampling circuit delivers to the processing device an output indicating the duration of the rectangular pulse. The processing device processes the output delivered thereto so as to decide the occurrence of an actual contact between the rotating body and the contact detection member.

Abstract: A slide cover apparatus for partitioning a machining head unit from a workpiece support unit comprises first and second cover assemblies. A main board and plural sub-boards of the first cover assembly are telescopically movable in a first horizontal direction, and the main board is formed with a vertically extending rectangular window. A center board and plural sub-boards of the second cover assembly which cover the rectangular window are guided by the main board for vertical movement. The main board is connected with a cross slide table of the machining head unit which is movable in the first horizontal direction, so as to be moved bodily by the cross slide table, while the center board is connected to be moved by a spindle head of the machining head unit.

Abstract: A numerical controller for a grinding machine, wherein one of plural reference sizing points is selected according to the contents of a numerical control program. Measured analog data indicating the diameter of a workpiece is received continuously to determine if the size of the machined workpiece coincides with the selected reference sizing point. Upon the coincidence of the size of the machined workpiece with the reference sizing point, a sizing signal is provided, and then machining control is changed in response to the sizing signal. An analog signal provided by a measuring device is sampled at a predetermined interval in a predetermined time. The analog signal is tested to see if the analog signal is in a predetermined range, which is decided based upon the temperature variation or vibrations of the grinding machine. And the result of the test is displayed to facilitate checking the output characteristics of the measuring device.

Abstract: A hydraulic power steering system includes a pump, a flow control valve, and a bypass control valve. The flow control valve responds to a pressure drop across a metering orifice disposed in a fluid supply passage so as to control the flow rate of operational fluid by bypassing part of the operational fluid to a reservoir. A spring chamber of the flow control valve is connected to the supply passage through a control orifice. The bypass control valve is disposed between the spring chamber and the reservoir so as to increase the amount of bypassed fluid by controlling the pressure in the spring chamber. The bypass control valve has a control spool, a load pressure introduction port connected to the upstream side of the control orifice for leading the load pressure to a first end of the control spool and a pilot port connected to the downstream side of the control orifice for leading the pressure in the spring chamber of the flow control valve to a second end of the control spool.

Abstract: An intelligent machining system employs a neural network for calculating machining conditions on the basis of attribute data or a workpiece and a grinding machine. The system comprises a reference machining condition calculating unit, a neural network which receives the attribute data and provides corrections, and a correcting unit for correcting the reference machining conditions by using the corrections. Corrections which cannot be determined by means of empirical expressions or theoretical expressions are determined appropriately by the neural network previously learned. The system determines corrections for the machining conditions on the basis of machining errors decided by a neural network. The system also detects time-series machining phenomena by sensors, processes the output detection signals of the sensors by a neural network to obtain machining circumstance data. The feed rate of the tool is controlled by a fuzzy inference on the basis of the machining circumstance data.

Abstract: A power steering apparatus for a motor vehicle is provided with a metering orifice arranged on a supply passage and a flow control device in parallel relation with the metering orifice. The flow control valve includes a spool and a spring and moves the spool against the force of the spring in response to the pressure difference across the metering orifice for returning an excess part of operating fluid discharged from an engine-driven pump to an intake side of the pump so as to keep the flow rate towards a power assist gear unit almost constant regardless of changes in rotational speed of the pump. A drooping device cooperating with the flow control valve is provided comprising a control orifice at the upstream of the metering orifice and a bypass valve in communication with a spring chamber of the flow control valve retaining the spring.

Abstract: A controller for a power steering apparatus in which operation fluid for generating assist torque is pumped by a motor-driven pump. The controller controls the flow rate of the operation fluid by changing the voltage supplied to the motor. The controller is provided with a section for generating a target value representing a target voltage to be supplied to the motor, a section for detecting the voltage actuary supplied to the motor, and a section for generating a voltage compensation value based on the detected voltage. The voltage compensation value is obtained by integrating a voltage difference between the target voltage and the detected voltage. The voltage compensation value is added to the target value to obtain a compensated target value. The motor is driven by a voltage corresponding to the compensated target value.