Abstract: To provide a platen structure and printer using the same that a platen in length comprises rigid members and a plurality of support parts of a recording medium are disposed in a perpendicular direction to the platen in length and constitute the platen together with relevant rigid members, thereby getting a warp due to an integrated molding of the platen or any aging change under influence of external environments free from occurrence.

Abstract: A work tank (20) for an electric discharge machine includes a tank wall (21) having an opening in a front surface and surrounding a workpiece; a front door (31) horizontally movable between an unlock position, where the front door is vertically movable, and a lock position, where the opening is closed in a generally liquid-tight relationship; a pair of brackets (32) attached to both sides of the front door and extending rearwardly; a handle lever (51) capable of pivoting about a fulcrum (35) and supported on at least one of the brackets; and a cam follower, fixed to the handle lever further forward than the pivot, the cam follower being vertically movable between a first position (H1) higher than the fulcrum and a second position (H2) lower than the fulcrum. The cam follower is fitted loosely into a groove (62) extending vertically and formed in a rail block (61). Horizontal movement of the cam follower is restricted.

Abstract: An electric discharge machining apparatus comprises a quill 8 movable in the vertical direction, at least one set of linear motor movers attached to the quill, symmetrically about a center axis of the quill, and a single set of linear motor stators facing the set of movers. An electrode mounting device (9) for holding a tool electrode (6) is attached to a lower end of the quill, coaxially with the quill. Preferably, the set of movers includes magnetic plates (12, 14) attached to the quill and a row of permanent magnets (11, 13, 15, 16) arranged on the magnetic plates, and the set of stators includes a yoke (31, 41) and a coil (32, 42) wound around the yoke. The quill has a hole (8a) in its center extending in the vertical direction, and an air cylinder (61) providing counter balance for the load of the quill is preferably disposed in this hole.

Abstract: A device applying device for applying tension to a traveling wire electrode including a controllable torque brake (11), a rotatable tension roller (2) around which a wire electrode (6) is wound, and a drive roller (4) directly linked to the brake means and pressed against the peripheral surface of the tension roller, and having a diameter smaller than the diameter of the tension roller. An alternative tension applying device includes a brake (11), a rotatable tension roller (2), an intermediate roller (12) having substantially the same diameter as the tension roller and formed integrally with the tension roller, and a drive roller (4) directly linked to the brake and pressed against the peripheral surface of the intermediate roller, and having a diameter smaller than the diameter of the tension roller.

Abstract: A wire cut electric discharge machining apparatus for machining a workpiece using a wire electrode traveling vertically between upper and lower wire guide devices includes a work tank in which the lower wire guide device and the workpiece are disposed, a lower wire guide drive unit disposed outside the work tank for driving the lower wire guide device horizontally in a direction of a first axis, a connecting shaft for connecting the lower wire guide device and the lower wire guide drive unit, a guide rail extending from the outside to the inside of the work tank in the direction of the first axis and being movable relative to the work tank in the direction of a second axis perpendicular to the first axis, and a support provided on the first guide rail for movably supporting the lower wire guide device.

Abstract: A flushing device having therein a chamber into which dielectric fluid is supplied for injecting dielectric fluid into a machining gap formed between a workpiece being machined and a wire electrode in a wire-cut electric discharge machine, a nozzle movable between a first position and a second position that is nearer the workpiece than the first position, for directing the dielectric fluid in the chamber toward the machining gap; and a spring or other bias apparatus for holding the nozzle in the first position.

Abstract: An EDM machine comprises a machining tank which moves along X-axis. An upper guide and a lower guide are formed integrally with a Y-axis moving block. The Y-axis moving block moves along a pair of rails that are placed on a horizontal plane. The horizontal plane is formed on a column within which portions of the upper and lower arms are located. By having the moving block move on rails that are placed on a horizontal plane, rattling of the moving block is eliminated and the machining accuracy is improved. The workpiece is also more accessible due to the machining tank moving in only one direction and since portions of the lower and upper arms are located within the column.

Abstract: A wire-cut electric discharging machine comprises a processing tank with an opening in one wall for the insertion of the lower arm unit. The lower arm unit is enclosed by a cylindrical pipe. The opening in the wall of the tank is sealed by a slide plate which moves in a direction parallel to the wall of the tank. Bellows interconnect the slide plate to the pipe 10 thereby providing a seal between the slide plate and pipe. The bellows expand and contract thereby allowing the processing tank to move along the axis of the lower arm unit while still providing a seal. Machining fluid flows through the pipe and around the lower arm unit. The fluid maintains the temperature of the lower arm unit at a constant value. The pipe protects the lower arm unit from being directly affected by the hydraulic pressure in the tank and also from being affected by motion of the tank. The sealing resistance for when the processing tank moves along the axis of the lower arm unit is significantly reduced.

Abstract: In a wire-cut EDM apparatus for cutting a workpiece (2) submerged in a processing tank (3) filled with a machining fluid (15), an opening (24) is made in the side wall of the tank through which an arm unit passes. A slide plate (14) also has an opening for passage of the arm unit and also provents leakage from the space between the opening 24 and the arm unit. In one preferred embodiment a fluid flow between the slide plate and arm unit is used to prevent fluid in the tank from escaping through the space between the slide plate (14) and the arm unit. Alternatively, a low frictional member may be placed between the arm unit and the slide plate for axially sealing the arm unit. Frictional resistance from movement of the lower arm unit is reduced and machining accuracy improved.

Abstract: A self-monitoring system for an automotive electronc control system such as an engine control system, an electronic anti-skid control system or electronic automatic transmission control system is adapted to check each segment of the electronic control system in order to detect faulty segments. To detect faulty segments, the self-monitor system checks inputs and outputs of the electronic control system. The checked data is stored in a memory which is not erased when the power supply is turned off. The self-monitoring system is associated with another automotive microcomputer which includes a display unit. The other automotive microcomputer is adapted to display the results of the checking operation of the self-monitoring system in response to a display request manually inputted from a manual unit to display identification of the fault segment and/or error condition thereof.

Abstract: A throttle control system for an internal combustion engine includes a controller connected to a sensor which is, in turn, associated with an accelerator to detect position of the latter to produce an accelerator position indicative signal. A filter or smoothing means is interposed between the controller and the accelerator position sensor. The filter and smoothing means is adapted to remove a component of the accelerator position indicative signal, which has frequency higher than a predetermined value.

Abstract: In a throttle control system in which a controller monitors accelerator position and controls throttle valve position accordingly rather directly coupling the accelerator to the throttle valve, a sensor monitors vehicle driving conditions related to desired engine output response and the controller adjusts the relationship between throttle valve position and accelerator position in accordance with the detected vehicle driving conditions. Factors indicative of driving conditions monitored by the sensor may include wheel slippage and selection of reverse transmission gear, in which case the controller will reduce the stroke of the throttle valve when either excessive wheel slippage or reverse gear is detected. Each monitored factor may be associated with a distinct characteristic curve relating throttle valve position to accelerator position with the appropriate characteristics being selected by the controller in accordance with the detected vehicle driving conditions.

Abstract: A watchdog timer works in concert with special computer program features to monitor program execution and reset the computer in case of malfunction. The computer CPU is programmed to periodically output one of an alternating pair of values to a register which holds the value for a comparator. The output value is compared to a predetermined value equal to one of the alternating output value. When the compared values are equal, the comparator outputs a reset signal to a counter. The counter counts clock pulses and if it counts to its full capacity before being reset by the comparator output, it outputs a reset signal which causes the computer to restart program execution. A second comparator may be provided to compare the alternating values to a reference value equal to the other values. Thus the comparators check for proper output of both signals and reset the counter only in response to receipt of both values.

Abstract: A method of controlling a power train composed of an engine and a transmission is disclosed wherein a control for the engine and a control for the transmission are integrated in a single control program. The method comprises detecting a change in the engine operating state, deciding which one of a plurality of control programs is required for the change in the engine operating state, placing a priority level on the control program decided, and activating the decided control program at a timing scheduled on the priority level in accordance with a predetermined control logic and controlling both the engine and the transmission in an integrated manner.

Abstract: An engine control system includes a stall-preventive feature in which prevailing engine conditions are checked against patterns known to lead to engine stall. A number of crucial engine parameters and continuously monitored, as are one or a number of subsidiary conditions, such as air conditioner operation and transmission position, which may significantly increase the probability of engine stall under certain, known conditions. When these known conditions are detected, engine parameters are sampled at regular intervals for a predetermined period of time to derive a number of parameter variation curves or patterns which can then be compared to similarly-derived empirical patterns which are known to lead directly to engine stall. When the current and predetermined patterns match or closely correlate, the engine control system is signalled to perform a stall-preventive operation. The stall-preventive operation consists of steps serving to increase engine output torque, decrease the load on the engine or both.

Abstract: A method of controlling a power train including an engine and a transmission wherein various input data are generated and among the various input data, a predetermined input data is common in controlling the engine and the transmission.

Abstract: A method of controlling a power train which drives a driving wheel of an automotive vehicle is disclosed. In the method, a slip rate is determined based on a difference between a ground speed of the vehicle and a peripheral revolution speed of a driving wheel and the engine output is increased or decreased so as to keep the slip rate at a predetermined target slip rate.

Abstract: A throttle valve control system for an internal combustion engine electrically controls throttle valve angular position in order to control intake air flow rate through an air induction passage of an engine. The system employs an accelerator to produce a signal representative of a required or demanded output speed. Actual output speed is monitored by means of a speed sensor. The actual speed is compared with the output speed demand derived from the accelerator signal to obtain the difference therebetween. Feedback control is performed on the basis of the calculated difference so as to control the throttle valve angular position to increase or decrease the actual output speed toward the speed demand value.

Abstract: A method and apparatus for controlling knock level in an internal combustion engine having knock induced vibrations and valve noises. Engine knock is decided when the knock induced vibration level exceeds at least one of the valve noise level and a limiting level. A basic value for the timing of ignition of the engine is calculated based upon engine operating parameters. The basic value is modified according to the result of the engine knock decision in a manner to operate the engine close to its knock level.

Abstract: An engine control system monitors engine operation by periodically sampling engine operating parameters and records variation patterns of the engine operating parameters as engine operation pattern data whenever any of a number of preselected specific engine operating conditions occur, such as engine stalling, acceleration, or deceleration. The control system normally controls the engine according to conventional engine control procedures and adjusts the control procedures in response to preselected engine operating conditions in accordance with a projected engine operation pattern derived from prerecorded engine operation pattern data and the detected specific engine operating condition. The engine operation pattern data may be repeatedly updated and/or accumulated during engine operation and may be held in a memory of the control system even after the engine is turned off.