Abstract: A tool setting device for a machine tool (10) having a numerical control (22) includes a gage unit (24) with a frame (26) adapted to be secured upon a slide (20) of the machine tool. A photodetector, which includes a source (96) and a receiver (98), is mounted upon the frame for generating a first signal indicating the arrival of the tip of a tool (18). A slide (64) mounted upon the frame carries an engagement head (38) adapted to be contacted and displaced by the tool tip. An LVDT (60) is mounted upon the frame in proximity to the engagement head for sensing its axial displacements. A control meter relay (86,88) is operatively connected to the LVDT and generates a second signal after initial displacement of the engagement head and a third signal after displacement of the engagement head to a reference position.

Abstract: A chuck for drilling tools is formed with a hollow shank which can be accommodated in a machine spindle, and is provided with a sleeve, which is adapted for accommodating a quick-change insert in the form of a tool or serves to accommodate a tool and which is coupled with the shank through an adjustable torque clutch device which, in the event of an overload, automatically disengages along with an axial relative displacement between the shank and the sleeve. The chuck has a high-frequency transmission device which is provided with a current source of its own, a high-frequency transmitter, a switch, which is closable during the axial relative movements between the shank and the sleeve, in the current supply circuit of the high-frequency transmitter and an external aerial ring.

Abstract: In a machine tool, a tool failure detection equipment in which chips or particles resulting from the machining of a work are collected and whether the tool is intact or broken is detected from the quantity of collected chips or particles. Chips or particles are sucked by a suction means and the quantity of collected chips or particles is detected by an optical detecting means. When the detected quantity is less than a predetermined value, the tool is detected as being broken.

Abstract: A contact detecting apparatus for detecting the contact between a workpiece and a tool in a machine tool which includes a coil mounted on a spindle head and connected to an AC power source for generating an induced current in a looped secondary circuit including the workpiece, a work table, a machine body, a spindle head, a brush, a clamp bar for clamping the tool on a tool spindle, springs interposed between the spindle and the clamp bar, the tool spindle and the tool, when the workpiece and the tool are moved relatively into contact with each other. The brush is kept contact with the clamp bar at the rotational axis of the tool spindle. A detector is connected between the AC power source and the coil for detecting a change in an electric signal caused by the contact between the workpiece and the tool.

Abstract: The invention comprises generally apparatus for use with an underground mine-shaft roof-bolting machine having a torque motor, a pinning rod held for rotation by the torque motor, a controllable arrangement for exerting upward thrust on the torque motor to force the pinning rod upwardly into the roof of a mine shaft, and a manual control for the upward thrust arrangement. The invention utilizes a light beam to detect buckling of the pinning rod and to disable the upward thrust arrangement.

Abstract: A tapping machine provided with a quill for rotatably supporting a spindle which holds a tap on one end thereof, a reversible electric motor for rotating the spindle and axially reciprocating the quill, an overload release clutch mounted in a power transmitting mechanism which is disposed between the quill and the motor, for suspending the power transmission between the quill and the motor when an overload is applied on the quill, and pulse signal generating means mounted between the clutch and the quill in the power transmitting mechanism for generating one pulse signal in response to each one pre-set unit distance of the quill during the forward motion thereof. The tapping machine performs a working cycle in good order wherein the spindle advances from the start position while being forwardly rotated until the number of pulse signals generated from the pulse signal generating means accords with a pre-set number and returns while being backwardly rotated back to the start position.

Abstract: A broken bit detector for use in conjunction with printed circuit board drilling machines or the like. The detector includes a light emitter and a light sensor contained within a pressure foot. The light emitter projects a beam of light through a central opening in the pressure foot and toward the light detector. Normally, the beam will be broken by a drill bit which passes through the opening. If a bit is not present, the light beam will not be broken and will be detected by the photosensor. Pressurized air is forced outward from both the light emitter and light detector in order to prevent any chips created by the drilling operation from striking the emitter or detector. The use of the air creates a shield which results in an accurate detector having a long life.

Abstract: An electronically controlled thread-cutting machine comprising a pulse controlled stepping motor for driving the thread-cutting tool, sensor means for scanning an adjustable thread depth and the torque on the thread-cutting tool, said scanning means comprising a counter for determining the steps of the motor and the number of revolutions of the thread-cutting tool respectively therefrom for determining the depth of the thread, and the current consumption of the motor being used for determining the torque transmitted to the thread-cutting tool, the motor being controlled in accordance with the torque and depth of the thread by micro-processor means for reversing the motor when the torque exceeds an upper limit torque and when the desired and preselected thread depth has been attained.

Abstract: A contact detecting apparatus for detecting the contact of a workpiece and a tool which comprises a coil mounted on the periphery of a spindle head and connected to an AC power source for generating an induced current in a first looped secondary circuit formed by the workpiece, a work table, a machine bed, a column, a spindle head, a tool spindle and a tool in the tool spindle when the workpiece and the tool are moved relatively into contact with each other, and a second looped secondary circuit formed by a tool change device, the tool, the tool spindle and the spindle head when a tool change operation is performed. A detector is connected between the AC power source and the coil for detecting a change in an electrical signal caused by contact between the workpiece and the tool or contact between the tool change device and the tool to output a contact detecting signal. Another detector is provided to detect that a contact detecting signal is not generated, even if a tool change operation has been performed.

Abstract: A tapping machine having a spindle which is moved reciprocally, i.e., in advancing and retracting direction while being rotated forwardly and backwardly for forming a female screw in a work with a screw tap attached at one end thereof. The machine is provided with driving means including a reversible electric motor, position sensing means for generating a sensing signal when the spindle is moved in advancing direction from a start position so far as a predetermined position, and temperature sensing means for generating a sensing signal when the temperature of the electric motor has risen exceeding a predetermined value. The machine normally repeats a working cycle wherein the spindle is moved in advancing direction from the start position while being rotated in forward direction until it is retracted to the start position soon after a sensing signal from the position sensing means has been generated.

Abstract: A critical torque detector is disclosed made up of a rotating input member, an output member supporting a drill and connected in a "flexible driving connection" with the input rotating member, and means for detecting difference in rotational speed between the input and output members due to a greater torsional resistance encountered by the drill during its operation than the critical torque predetermined for a specific drill. The input and output members are drivingly connected, as by a coil spring, magnetic repelling forces and so on, so as to rotate conjointly whenever a torsional resistance or a torque encountered by a running drill is lower than the predetermined value, but they are not always rigidly connected. Upon occurrence of greater torque imposed on the drill, the output member will be permitted to delay in rotation as compared to the input member. Such difference in rotational speed can be taken out mechanically or electromagnetically as a signal to detect occurrence of the critical torque.

Abstract: A critical torque detector is disclosed made up of a rotating input member, an output member supporting a drill and connected in a "flexible driving connection" with the input rotating member, and means for detecting difference in rotational speed between the input and output members due to a greater torsional resistance encountered by the drill during its operation than the critical torque predetermined for a specific drill. The input and output members are drivingly connected, as by a coil spring, magnetic repelling forces and so on, so as to rotate conjointly whenever a torsional resistance or a torque encountered by a running drill is lower than the predetermined value, but they are not always rigidly connected. Upon occurrence of greater torque imposed on the drill, the output member will be permitted to delay in rotation as compared to the input member. Such difference in rotational speed can be taken out mechanically or electromagnetically as a signal to detect occurrence of the critical torque.

Abstract: A tracing milling machine having a conventional tracing milling machine controller for controlling a servo movement of the machine is provided with a novel tracing command controller for automatically generating tracing commands to be supplied to the tracing milling machine controller for the purpose of enhancing automation of the tracing milling operation of the machine. The tracing milling machine is further provided with an automatic tool changer, for enabling an automatic tool change of a cutting tool attached to a spindle of the machine during the automated tracing milling operation of the machine.

Abstract: A numerically controlled machining center has a tool magazine, automatic tool changer, workpiece shuttle, and a workpiece magazine which holds enough workpieces for operation by the machining center for an entire shift of approximately eight hours. The numerical controls are programmed to perform predetermined machining operations on each workpiece, in turn, and to replace each finished workpiece with a fresh workpiece at the end of each machining program. A proximity switch is mounted on the machining center for checking tools to detect broken or incorrect tools. The tools are positioned adjacent to the proximity switch and are rotated while the output of the proximity switch is counted for one complete rotation of the tool to determine the number of radially extending teeth on the tool. If the tool has too few or too many teeth, thus indicating a broken or incorrect tool, it is replaced by another tool of the same type.

Abstract: An accessory for tool machines is provided comprising a tool holder isolatedly carried on bar springs to effect a floating mount. The holder yields in response to selective load stress during cutting and is restricted to a linear force path to relieve stress. The yielding movement relieves stress and can operate signals in the event of overload or operate control means such as switches to cut off tool machine motors.

Abstract: A critical torque detector is disclosed made up of a rotating input member, an output member supporting a drill and connected in a "flexible driving connection" with the input rotating member, and means for detecting difference in rotational speed between the input and output members due to a greater torsional resistance encountered by the drill during its operation than the critical torque predetermined for a specific drill. The input and output members are drivingly connected, as by a coil spring, magnetic repelling forces and so on, so as to rotate conjointly whenever a torsional resistance or a torque encountered by a running drill is lower than the predetermined value, but they are not always rigidly connected. Upon occurrence of greater torque imposed on the drill, the output member will be permitted to delay in rotation as compared to the input member. Such difference in rotational speed can be taken out mechanically or electromagnetically as a signal to detect occurrence of the critical torque.

Abstract: A numerically controlled machining center has a tool magazine, automatic tool changer, workpiece shuttle, and a workpiece magazine which holds enough workpieces for operation by the machining center for an entire shift of approximately eight hours. The numerical controls are programmed to perform predetermined machining operations on each workpiece, in turn, and to replace each finished workpiece with a fresh workpiece at the end of each machining program. A proximity switch is mounted on the machining center for checking tools to detect broken or incorrect tools. The tools are positioned adjacent to the proximity switch and are rotated while the output of the proximity switch is counted for one complete rotation of the tool to determine the number of radially extending teeth on the tool. If the tool has too few or too many teeth, thus indicating a broken or incorrect tool, it is replaced by another tool of the same type.

Abstract: A torch head is provided for an oxygen-cutting torch machine comprising, in combination, a torch head; a first torch mounted on the torch head for cutting perpendicular cuts; and a second torch mounted on the torch head for cutting at an angle to the perpendicular; the mounting for the second torch having two parallel side shaft members and two parallel cross shaft members, each pivotably attached to the other at spaced locations so as to define a parallelogram swinging means in which the four members move pivotably and in parallel together; the second torch being pivotably mounted to one of the side members so that the second torch can be positioned at an angle to the perpendicular according to the relative movement of the parallelogram members; a reciprocably movable drive means mounted on the torch head for swinging the parallelogram swinging means; a shaft member rotatable about a point fixed to the torch head and having two spaced pivot mountings, one on each side of the fixed point, one pivot mounting b

Abstract: A machine control circuit in which the sharpness of a machine tool cutting edge is sensed as a function of the pressure in a hydraulic tool-feed cylinder, and in which the machine is automatically de-activated for tool inspection after a pass is completed when the feed pressure reaches a preselected level.

Abstract: A lead screw tapping unit is disclosed wherein a tap or thread forming die is mountable on a tool support spindle which is longitudinally movable with a nonrotatable quill. The spindle is rotatably driven by a reversible drive motor and has a lead screw carried thereon which cooperates with a lead nut to effect controlled inward feeding and withdrawal of the tap relative to a workpiece. The lead nut carries a cam bushing which is operative to actuate a safety switch and deenergize a drive motor to stop rotation of the spindle should the spindle and tap undergo a thrust overload condition, or if seizure occurs between the lead screw and lead nut.

Abstract: A chuck unit for boring, drilling or cutting tools having a safety clutch so as to prevent overload resulting from broken or dull tools and wherein when the clutch is actuated by an overload a transmitter in the tool support is actuated to radiate a signal which is detected by a receiver so as to indicate the malfunction and/or stop the tool so as to prevent damage to the tool or workpiece.

Abstract: An electric motor driven drill and a battery therefor are mounted within a toolholder for a machine tool. The battery is coupled to the motor through a centrifugal switch which closes when the toolholder is rotated about its axis above a predetermined speed and opens when the rotary speed of the toolholder falls below the predetermined speed. The toolholder is mounted in the spindle of a machine tool and the drill turns on when the spindle is rotated and turns off when the spindle stops, the rotary speed of the spindle being added to the rotary speed of the drill in one direction of spindle rotation and subtracted from the rotary speed of the drill in the opposite direction of spindle rotation.

Abstract: A detecting device and control system for use with machine tools to detect the breakage of a tool bit, the presence or absence of a portion of a workpiece, and other improper conditions that might result in the production of imperfect work, and to prevent normal operation of the machine whenever any such conditons exist.

Abstract: A device for precluding improper operation of a stamping press including a control cylinder the piston of which is impinged on one side by a pressure medium and on the other side by a pressure medium having a variable constant pressure. Electrical switch elements are utilized to prevent the stamping operation from progressing unless preset conditions exist.

Abstract: A system is disclosed for detecting the state of a rotating machining tool, such as a drill bit, in a machining head. The system employs an electromagnetic detector having a coil connected in series with an oscillating circuit. As the tool rotates, its lands and flutes cause detectable variations in reluctance which are used to modulate the output of the oscillator circuit. The modulated oscillator output is monitored as an indication of the state of the tool.