Abstract: A shaping or cutting machine, especially a skinner, at which an operator hand-feeds material to be cut or shaped toward a blade. Hand proximity detection devices are provided for operator safety; machine-vision across a surveilled volume before the blade, and conduction sensing devices. The blade is mounted on a rapidly retractable frame. Power from release of a spring physically moves the blade to a safe position if a hand is sensed. A gripping roller is driven by a rapidly stoppable motor.

Abstract: The disclosure describes techniques for a self-test of a graphics processing unit (GPU) independent of instructions from another processing device. The GPU may perform the self-test in response to a determination that the GPU enters an idle mode. The self-test may be based on information indicating a safety level, where the safety level indicates how many faults in circuits or memory blocks of the GPU need to be detected.

Abstract: A first electrode and a second electrode carry out welding in cooperation with each other. A power supply applies a first voltage between the first electrode and the second electrode. A control device controls whether to carry out welding on a first object on the basis of information that varies with a material of the first object and that has been detected in a state where the first object is in contact with the first electrode and the second electrode.

Abstract: A blender collar assembly including a plunger moveable between a lower position where a blade assembly is prevented from coupling with a motor, and an upper position where the blade assembly is able to couple with the motor. The plunger includes an arm extending upward and having a u-shaped feature, and a protrusion associated with the u-shaped feature. The assembly further includes a concentric interlock ring rotating responsive to rotation of a blender jar. The interlock ring including a first portion engaging the u-shaped feature preventing the plunger from moving upward, a second gap portion not engaging the u-shaped feature enabling the plunger to move upward and downward within the collar, and a key engaging a protrusion of the blender jar as the plunger moves upward preventing the interlock ring from rotating while the second portion is rotationally aligned with the u-shaped feature.

Abstract: A handheld work apparatus has a housing with a guide bar affixed thereto. A saw chain is driven along the guide bar which defines a central plane. A drive element for the chain is in a sprocket wheel space delimited by a sprocket wheel cover. The cover has a longitudinal edge which delimits the space adjacent to a first side of the saw chain. The longitudinal edge has a length from an entry region to a discharge opening. Over at least 50% of this length, the longitudinal edge is at a distance (L) to the housing. The distance (L) corresponds to the chain width (a). The distance of the longitudinal edge of the cover increases at the discharge opening in the running direction of the first side. The largest distance (b) of the longitudinal edge to the central plane is at least 110% of the smallest distance (c).

Abstract: A control knob (10) includes a base (14) and a shaped wall (12). A plurality of sensor elements (32) are located within and circumferentially spaced around said shaped wall. Processor circuitry (40, 50) is connected to the plurality of sensor elements (32) for controlling an end-use device. The processor circuitry (40, 50) senses user touch commands on both sides of the shaped wall (12), and determines user desired commands based on the sensed user touch commands.

Abstract: The invention relates to a method for opening a movable panel of a motor vehicle, including the following steps: Step A (1)—the presence of at least one body part of a person is detected by a capacitive or non-capacitive sensor; Step B (2)—the person is authenticated as being authorized to unlock the vehicle by an authentication means; Step C (5)—a virtual switch is produced by projecting a light pattern onto the ground on which the motor vehicle is standing; and Step D (6)—the person positions his/her foot so as to obscure the virtual switch in a predetermined manner; Step E (7)—if the foot is not positioned in the predetermined manner, a signal is sent to restart step D, or if the foot is positioned in the predetermined manner, a control means opens the movable panel.

Abstract: A power tool includes an actuator that moves an implement, an infrared sensor, and a range sensor. A controller in the power tool receives temperature data and range data corresponding to objects in a region proximate to the implement. If an object in the predetermined has a temperature within a predetermined range and is identified as being within a predetermined minimum distance of the moving implement, then the controller deactivates the actuator to halt the implement.

Abstract: A process for detecting an alarm in an operating machine (1), so that an operator (7) is able to interact with such a machine (1) determining a connection between the machine and the ground, comprising the steps of: determining a current value of a main parameter representative of an electric interaction between said operator (7) and said operating machine (1) under a condition of normal operation of said machine (1); comparing said determined current value with a main reference value; activating an alarm procedure as a function of said comparison.

Abstract: A dunnage discharge chute includes features designed to prevent injury to an operator of a dunnage producing machine. The dunnage discharge chute includes at least one door with sensors that monitor the position of the door and output position signals. The position signals are received by a controller which outputs a control signal that disables operation of the dunnage producing machine based at least in part on a change in the position signals over a predetermined period of time. Additional sensors may detect whether the door is open beyond an upper open position, and a relay may disable operation of the dunnage producing machine immediately if the door is opened beyond the upper open position. Thus, if the operator reaches in through the door, the dunnage discharge chute will disable operation of the dunnage producing machine.

Abstract: A protective device for use with table-top circular saws that operate a tool designed as a rotating, disk-shaped sawing tool includes at least one actuator unit and at least one protective unit. The at least one actuator unit moves the protective unit into a protective position on the tool.

Abstract: A detection system senses the location of a preselected color within one or more monitored zones of a machine tool. If the operator of a machine tool wears a red glove, the system detects the location of the color red and defines various monitored zones through the use of synchronization signals and a time circuit. The system can take action based on the location of the particular monitored zones in which the red glove is sensed. These actions can include the sounding of a horn, the lighting of a light, or the deactivation of the machine tool.

Abstract: The invention describes a safety system (22) for a production unit (1) for bending a sheet metal part (3), in particular for a bending press (2), with a stationary bench beam (13) and a bending tool (4, 5) for a displaceable press beam (13), and with a light beam transmitter and receiver system (23) monitoring an operating region to prevent trapping of a foreign body. The bending tool (5) disposed in the press beam (13) is provided in the form of a slat pack (34) comprising at least one reference slat (35) and at least one tool slat (33) which can be displaced relative to it, which are provided with recesses (60) traversing them in the direction of a thickness (32). When oriented in alignment, these form a beam passage (65) for a light beam (9), in particular a laser light beam, extending parallel with an end face (8) of the press beam (13). An embodiment of the bending tool is possible in the form of a skeleton tool.

Abstract: The invention provides a sensor assembly which can sense human tissue in a protected area of a machine. An emitter plate and a plurality of sensor plates are disposed co-planar to each other and adjacent to the protected area of the machine. An electric field is generated between the emitter plate and the sensor plates and directed towards the protected area. The sensor plates produce electrical signals corresponding to the electric field received at the sensor plate. The electrical signals are amplified, measures, and analyzed to determine if human tissue is within the protected area. If human tissue is detected, a machine interface circuit will shut down the machine to prevent injury.

Abstract: A method and an optoelectronic sensor are provided for ensuring the safety of a machine tool having a first tool part carrying out working movements in the direction of a second tool part. The sensor monitors a three-dimensional protected field between the tool parts of the machine tool. At the start of a working movement of a first tool part of the machine tool, the extent of the protected field in the direction of the working movement is smaller than the extent of the open gap between the tool parts. On a continued working movement, the extent of the protected field is continuously reduced and the protected field is held in the center of the open gap. Thereafter, on a further continued working movement, the extent of the protected field is maintained and the protected field is held in the center of the open gap. The sensor is finally deactivated.

Abstract: The invention relates to a method for securing a machine tool comprising a first tool part that carries out work movements in the direction of a second tool part in order thereby to carry out a machining process on a workpiece, wherein an optoelectronic sensor monitors a three-dimensional protected field between the tool parts in that light is transmitted along an open gap formed between the tool parts by means of a transmitter device and is detected by means of a receiver device which includes a matrix of light-sensitive elements, wherein the first tool part is stopped if individual light-sensitive elements or specific groups of the light-sensitive elements do not receive any light. In the method in accordance with the invention, relative positions between individual workpiece areas or measured values related to individual workpiece areas are determined from the signals delivered by the light-sensitive elements.

Abstract: A device for monitoring an area of coverage on a work tool may comprise a lighting unit, a camera, and an evaluation unit. The lighting unit may be adapted to emit light rays for illuminating the area of coverage. The camera may be adapted to detect two-dimensional images of the area of coverage, and the camera may comprise receiving elements arranged linearly. The evaluation unit may be coupled to the camera to evaluate the output signals of the receiving elements to determine a distance value for each receiving element based on the light rays emitted by the lighting device and reflected back from the area of coverage. The evaluation unit may have at least one switching output coupled to the work tool to activate the work tool such that the work tool is operational only if no object is located in the area of coverage.

Abstract: A system for stopping a spinning table saw blade is comprised of a pin assembly disposed adjacent to a saw blade assembly for stopping a spinning saw blade. A receiving block is disposed on a side of the saw blade opposing the pin assembly for receiving the tip of the pin assembly. A driving assembly is coupled to the pin assembly for driving the pin assembly into the spinning saw blade into the receiving block. Finally, a sensing assembly is coupled to at least one of the saw blade assembly and the driving assembly for sensing encroachment of a user's hand in a pre-defined zone. In use, upon sensing a user's hand the sensing assembly signals the driving assembly to stop the spinning saw blade by driving the pin assembly through the saw blade and into the receiving block.

Abstract: A safety device for a machine has a first machine part for carrying out a working movement towards a second machine part. It also has at least a first and a second optical barrier moving along with the first machine part during the working movement. The first optical barrier runs ahead of the first machine part by a first distance, and the second optical barrier is arranged at a second distance from the first optical barrier. A control unit is designed to stop the working movement of the first machine part when the first optical barrier is interrupted. A test unit allows to test whether the second optical barrier has been interrupted once the first machine part has been stopped. A blocking unit serves for blocking the working movement as a function of the test result from the test unit. Using this safety device it is possible to determine an overtravel of the first machine part in a simple and reliable manner.

Abstract: The invention relates to a production unit (1), in particular a bending press, and a method of operating the latter in order to shape workpieces of sheet metal between two press beams (15, 16) equipped with bending tools (36, 37) and displaceable relative to one another by means of a drive system (27), and having a control unit (47). The control unit (47) incorporates a detection system and has at least one detection means which is connected so as to communicate with the detection system in order to transmit data and/or signals.

Abstract: A safety device, particularly for industrial machines, such as for example bending presses provided with an upper tool that is driven in abutment toward a lower die, at least one blank, such as a metal plate, a bent plate or a box-like element, being interposable between the die and the tool, the safety device comprising a glove worn by the operator, provided with first electrically conducting regions located at the back with no conducting regions at the palm; the glove constitutes, at contact with the machine and/or with the blank, an element for transmitting electrical signal between the machine and a control unit (CU) to stop descent of the tool.

Abstract: A safety interlock and retraction mechanism for all types of presses comprising a sensing or activating valve which does not apply full force to a press ram until the ram displaces to the expected work material thickness and a pneumatically operated retraction mechanism which eliminates the need for a return spring. The art differentiates between the thickness of an operator's finger relative to a work material thickness in order to promote safety. The art further provides an increased press ram force by eliminating the return spring force subtracting from the ram force.

Abstract: The present invention relates to a safety apparatus for a machine such as a press brake. The machine has a first and a second machine part which perform a working movement towards each other. The first machine part has a leading edge in the direction of movement, and the leading edge defines a plane of movement. The safety apparatus has a plurality of first light barriers which run with the first machine part during the working movement, with the light beams of the first light barriers extending parallel to the plane of movement and being distributed in the region of the plane of movement in such a way that they run in advance of the leading edge with an increasing distance as viewed in the direction of the working movement. Furthermore, there is a control unit which stops the working movement in response to the first light barriers. There is also a configuration device, by means of which selected ones from the first light barriers can be deactivated at least for the duration of the working movement.

Abstract: Safety system for a manufacturing machine provided with at least one tool which can injure the operator, comprising a pair of gloves to be worn by the operator and provided with an outer surface of dielectric material and an electrically conductive inner surface; an alarm signal generator connected to the conductive inner surface; a processor unit connected to the metal machine members and to the at least one tool via a safety circuit arranged to sense the alarm signal when the operator cuts one of the gloves on coming into contact with one of the mechanical members of the machine, the processor unit being provided with circuitry for interrupting machine operation on sensing said alarm signal, in which the alarm signal is an alternating current signal the intensity of which is established by the processor unit on the basis at least of at least one of the physical characteristics of the operator, e.g. the electrical conductivity, as measured by a suitable circuit for determining at least this characteristic.

Abstract: A safety catch device of a sealing machine has a baffle and a probe set. The baffle is pivotally arranged at the opening of the machine body. A conducting sheet is provided at the rear side of the baffle. The probe set has a first probe and a second probe, which are connected to a circuit unit with signal cables. The front end of the first probe exceeds the front end of the second probe by a certain distance. The front end of the first probe contacts the conducting sheet. The front end of the second probe keeps a certain distance from the conducting sheet. When the baffle swings backwards, the conducting sheet contacts the front end of the second probe to transfer signals to the circuit unit for stopping the film sealing operation. The safety of operation can thus be greatly enhanced to effectively avoid occurrence of hazards.

Abstract: A guard assembly for a compound miter saw includes an upper blade guard assembly, a lower blade guard assembly having a movable guard pivotally mounted in the upper blade guard assembly and a linkage assembly. The lower blade guard is pivotally mounted in the upper blade guard assembly. The linkage assembly including an inner link pivotally interconnected with the movable guard and the upper blade guard assembly controls the movement of the guard. A lock release mounted on the upper blade guard assembly locks the movable guard in position.

Abstract: A guard device for machines such as pressbrakes, guillotines, stamping machines and the like, in the case of which a first machine part performs working movements toward a second machine part. At least one photoelectric detector, more especially a laser photoelectric detector, has its light beam extending perpendicularly to the direction of working movement and is able to be so positioned between the two machine parts at one thereof that its light beam is at a safety distance from such machine part, such safety distance being able to be set by means of a guard device arranged adjustably on this one machine part, such guard device bearing the at least one photoelectric detector. A halting mechanism is adapted to arrest the working movement on interruption of the light beam and a switching off mechanism serves for switching off the halting mechanism directly prior to interruption of the light beam.

Abstract: A punch and press system includes a low voltage safety circuit and a high voltage control circuit. The high voltage control circuit is further divided into a high voltage low current region and a high voltage high current region. The high voltage low current region is isolated from both the low voltage safety circuit and the high voltage high current region of the control circuit. As the upper tool of the press strikes an object, the object's conductivity will govern whether the press will continue to act on the object. Thus, if the object is conductive, then the upper tool will continue to act on the object. If the object is not conductive, then the upper tool will raise to a neutral position.

Abstract: A safety apparatus and method for protecting an object entering into the path of a moving blade in a press brake (10) is provided, which includes laser emitters (22) and receivers (24) for mounting in fixed relationship to the leading edge (36) of the blade (18) to provide a plurality of light beams (26) in advance of the blade (18). A controller (51) including halting means (57) for halting advancing movement of the blade in response to certain contingencies is also provided, wherein the contingencies may include those involving interruption or obstruction of the light beams (26) and those which are indicative of a fault with the press or the safety apparatus itself. The controller (51) also includes laser control and processing means (54), blade movement control means (56), blade position processing means (58) and vibration sensing means.

Abstract: Safety apparatus and method for protecting an object entering into the path of a moving blade in a press brake (10). The apparatus includes laser emitters (22) and receivers (24) for mounting in fixed relationship to the leading edge (36) of the blade (18) to provide a plurality of light beams (26) in advance of the blade (18). A controller (51) including halting means (57) for halting advancing movement of the blade in response to certain contingencies is provided. These contingencies include those involving interruption or obstruction of the light beams (26) and those which are indicative of a fault with the press or the safety apparatus itself. Accordingly the controller (51) also includes laser control and processing means (54), blade movement control means (56) and blade position processing means (58) which operate in conjunction with the halting means (57) to enable overriding control of the movement of the blade (18).

Abstract: The invention concerns a safety device on metal-forming machine tools, in particular on pneumatic pressing machines, used in the execution of short-stroke pressing processes, for preventing intervention in the danger zone during the tool working movement and unintentional closure movements. The machine essentially comprises a machine housing, a power-generating system, a control system and a tool arrangement with a fixed part and a movable part, and the actual metal-forming tool connected thereto. The object of the invention is the highly reliable prevention of injuries owing to inattentiveness in spite of hands' being left in the immediate danger zone.

Abstract: A cycle of operation of an attaching apparatus begins with determining whether an operator's extremity is in an area in which it can be struck by a downwardly moving ram during attachment of two fasteners to each other and to a material therebetween. If it is determined that the operator's extremity is not in the area in which it can be struck by the downwardly moving ram, the remainder of the cycle of operation is completed. If it is determined that the operator's extremity is in the area in which it can be struck by the downwardly moving ram, the cycle of operation must begin again.

Abstract: A power trowel handle has controls that permit electronically operating the functions of an engine on the power trowel from the handle. The engine includes a servo controlled carburetor which will permit injecting, upon initial closing, a circuit for starting a quantity of fuel for starting a two cycle engine, which normally has to be done manually, as well as permitting control of a throttle using a trigger switch on the handle. The power trowel further has an elongated pole braced with a slider to prevent twisting under torque and to permit better control of the power trowel from a remote handle. The handle grip is usable in either the elongated pole position, or directly on a shroud for the power trowel.

Abstract: A safety device detects when a worker's hand enters a hazardous region between rollers of a kneading machine, and stops rotation of the rolls to prevent an accident. Each time the rollers are stopped, the orientation of photoelectric sensors is switched from the vicinity of the gap between the two rollers to a test reflection member, and the quantity of received light is compared to a predetermined value, to prevent workers form starting work without knowing a fault or accident has happened. More specifically, a bar electrode of an electrostatic capacitance sensor is disposed above and near the gap between the two rollers, for detecting a physical quantity that is changed by entry of a worker's hand. When the electrostatic capacitance detected by the sensor exceeds a predetermined value, a judging circuit supplies a control signal to stop a driving unit that operates the kneading machine. Heat ray sensors or photoelectric sensors may be used as alternatives to electrostatic sensors.

Abstract: A tube bending machine having a rotatable bend die, a pressure die, a clamp die, an actuator and a controller. A clamp assembly holds the clamp die and includes a base, a clamp die holder which is spring biased away from and slideably engageable with the base. A spacer is also attached to the base and is moveable between positions. A gear rotatably mounted to the base is attached to a first and second cam by a shaft and the gear moves on a rack. The first cam is followed by a cam follower which moves to allow the spacer to change positions. The clamp die holder may move toward the housing in case the clamp die engages an obstruction, thus avoiding damage or injury to the obstruction. A second position of the spacer substantially blocks the space between the clamp die holder and the base, thus making a substantially rigid connection between them. The second position is used during the tube bending process.

Abstract: A safety system including two command buttons (7, 8) spaced apart from one another geographically, and obliging an operator to use both his hands to control a radiology appliance, or one hand and a foot, is completed by a protocol including, on a single button (7), a short pulse followed by a long pulse during which the maneuver is carried out.

Abstract: A press brake safety apparatus for use on a press brake (10) of the kind having a moving blade (18) having a leading edge (36) and a platform (38) against which an item (42) may be pressed, the safety apparatus comprising at least one beam (26) of light mounted at a level marginally forward of and substantially parallel to the leading edge (36) so as to move with the blade (18), the interruption of the or each beam (26) causing the movement of the blade (18) to stop and thereby halting operation of the press brake (10) without the leading edge (36) contacting the item (42).

Abstract: A safety guard system provided for a machine having a ram which is movable toward and away from a work zone and an actuator which is operable for driving the ram through a ram stroke toward the work zone. The safety guard system includes a safety guard mounted for movement along a guard path between open and closed positions with respect to the work zone. The safety guard is releasably coupled to the ram for movement during the ram stroke from the open to the closed position before completion of the ram stroke, and the safety guard is arranged to decouple from the ram upon either one of reaching the closed position or earlier encountering an obstruction in the guard path. A guard sensor effects a first signal upon the safety guard reaching the closed position, and an object sensor effects a second signal upon decoupling of the safety guard from the ram.

Abstract: The safety switch assembly is designed to provide a switch assembly to a tool, such as a meat slicer, in order to prevent the operation of the tool without manually holding the pressure sensitive safety handle. The assembly contains a control box having a ground fault interrupter/on-off switch, signal device, a power receptacle and a control circuit. A safety handle is installed on the tool and the handle has two pressure sensitive strips which function as a dual force sensing resistor and is connected to an electric cable that connects the safety handle to the control box which houses the control circuit. The operation of the tool requires that power be supplied to the control box. When the individual grips the safety handle and squeezes the handle, the control box provides power to the tool itself.

Abstract: A unit for controlling the operation of the electric motor is provided together with a control device, electrically connected to the body of the operator, to act on the control unit via a relay means in such a manner as to halt and reverse the rotation of the electric motor following conductive contact between the operator's body and the metal component. For receiving and supporting the feet of the operator, two conductive plates insulated from the ground are provided in such a position that the operator rests his feet via conductive shoes on them when working with the machine. The plates are connected to the control device, and the metal component is electrically connected to earth. The support plates are electrodes for the passage of low voltage electric current from one plate to the other via the body of the operator. The control device stops the motor following conductive contact between the operator's hands and the metal component.

Abstract: The safety switch assembly is designed to provide a switch assembly to a tool, such as a meat slicer, in order to prevent the operation of the tool without manually holding the secondary switch and the depression of a button. The assembly contains a control box having a ground fault interrupter/on-off switch, signal device a pneumatic switch power receptacle and a control circuit. A safety handle is installed on the tool and the handle has an actuation button and a safety button, which functions as a four way valve, installed in series, and connected to an air tube that connects the safety handle to the control box pneumatic air switch. The operation of the tool requires that power be supplied to the control box. When the individual depresses the safety and squeezes the button on the handle, the control box provides power to the tool itself.

Abstract: A method and a device for protecting against a press overload is disclosed whereby, when an excessive pressure which exceeds a specified hydraulic pressure is transmitted to a pressure chamber of a press cylinder, this excessive pressure activates the punching of a shear plate by a shear piston and the excessive pressure is released by the shear piston.

Abstract: A palm button switch apparatus includes a housing, a solid palm button fixedly mounted on the housing, a guard fixedly mounted on the housing and surrounding the periphery of the palm button. A bore extends through the housing and into the palm button. The bore has an open first end and a second end covered by the palm button. A proximity switch having a sensing end is mounted in the bore with the sensing end disposed in proximity with the palm button for detecting the presence of an operator's fingers on the palm button. The housing, the palm button and the guard are integrally formed as a one-piece unit from a molded plastic.

Abstract: A vision system for detecting mispositioned parts during the operation of a powder metal press and preventing damage to the press and tooling associated therewith, wherein the gross level of light is read at specified locations of the press during predetermined points in the press stroke, compared to gross light levels established during a teaching stroke of the press, with the press being automatically deactivated when the difference between the gross light level read and the established gross light level is not within a predetermined range.

Abstract: A sewing machine controller which inhibits compensation sewing if the cloth presser is raised, if the treadle switch is activated or a proximity switch mounted near the needle detects the operator's hand.

Abstract: A press comprising a frame with an anvil support and a punch carrier, the latter being mounted on the frame so as to be movable between two ends of travel towards and away from the anvil support. A piston and cylinder arrangement is arranged to act on the punch carrier to urge the latter in a direction towards the anvil support. That one of the two ends of travel of the punch carrier which iscloser to the anvil support is defined by a part or parts of the press itself. A limit switch is operable by means of the motion of the punch carrier, or a part connected thereto, in the said direction when the remaining available travel is a distance which is less than the thickness of an operator's finger, to enable the piston and cylinder arrangement to act on the punch carrier with a working force in the said direction up to the end of its travel.

Abstract: A safety power tool is described which is useful as a hardware insertion press. It includes a punch aligned slideably between an anvil and a short stroke power ram adapted to move the punch toward the anvil through a relatively short distance and a spacer movable to an opening between the ram and the punch to contact the ram at one end and the punch at the other end for transmitting the short stroke motion of the ram to the punch. A long stroke retraction actuator is connected to the punch for withdrawing the punch from the anvil when the spacer is moved laterally to an inoperative position to provide a relatively large clearance space between the punch and the anvil but with the spacer out of the way, the ram is rendered ineffective to apply pressure to the punch thereby preventing injuries.

Abstract: In a controlled-access apparatus for agricultural food industries, means is provided within the space located between the rotary tool-holder and the edge of the opening of the vessel of the apparatus for a protection and access-control device which performs a double function, namely that of protecting the user against accidental bodily injuries and that of allowing penetration of/or access to agricultural food products or ingredients, utensils or instruments having predetermined characteristics such as zero electrical conductivity and nonmagnetic properties.

Abstract: The present invention discloses both a safety sensing system and a method of providing safety protection for presses or like industrial machines having a reciprocally movable operating head, ram, tool or beam. The basis of the system is the provision of a first beam (or a plurality of first beams) each of which is placed across and in front of the intended direction of travel of the pressing tool or blade. A second beam is arranged in the intended direction of travel and is broken by the tool or blade when the latter has reached a predetermined minimum height above a workpiece. A control system is provided which, during the operating stroke of the blade retracts the blade if any one or more of the first beam(s) is or are broken but the second beam is not broken. However, once the second beam is broken, the stroke of the blade is completed even if the first beam(s) is or are broken, for example, by folding of a pressed workpiece.

Abstract: This safety monitoring system for punch press operators is designed to prevent the operators from being injured by such presses or other factory equipment. Primarily, it consists of a pair of wrist units which are strapped to the wrists of the operators, and which include optical fiber cables and a latching assembly, and the optical fiber cables are used in cooperation with a pair of identical electronic circuits employing LED's, a light sensitive transistor, a pair of other transistors, a zener diode, and a relay, for instantly shutting a punch press on or off.