Abstract: A retractable step assembly (10) includes a step (12) pinned to the lower ends of a pair of swing arms (14, 16) depending downwardly from a bracket (30) for mounting the step assembly to the underside of a vehicle. An electric motor (20) powers the upper end of a swing arm (14) to rotate the two swing arms between retracted and extended positions. A clutch assembly (24) is interposed between the electric motor and the swing arm (14) to allow the motor to continue to operate to the end of its cycle if the step or swing arm become obstructed. A lock assembly (170) is provided to lock the step in retracted position, with the lock being automatically disengaged when the step assembly is actuated to extend the step from retracted position.

Abstract: A movable section of a machine is enclosed by a fence and a door. A locking device provided on the door is controlled by a movable section control circuit. In the movable section control circuit, an operating switch outputs either a movable section ON signal or a movable section OFF signal. A door switch outputs an ON signal representing that the door is open. A switch means constitutes a self-holding circuit which uses an AND signal constituted of the movable section OFF signal from the operating switch and a rotation stop signal as a reset input signal and an OR signal constituted of an ON signal from the door switch and a rotation-presence signal as trigger signal to provide the locking device with a control signal. When a sensor fails, the locking devive is not unlocked even if the operating switch for driving the movable section is closed.

Abstract: The invention discloses a safety circuit for electrically operated devices, which turns on the device in question, based on its position and design, only if handling and posture by the operator is completely correct and proper and the circuit, moreover, is static and insensitive to outside influences due to the use of sensor switches.

Abstract: A manually displaceable implement for ground treatment comprising a dead-man safety based on an automatic lowering and blocking of the running wheels (5). A stop (10) is provided on the implement for blockage, against which at least one lowered running wheel (5) rests. The automatic lowering of the running wheels (5) is accomplished by a two-part height adjustment rod (4), which is maintained together by an emergency release element (12). In an emergency, this emergency element (12) is activated by a ripcord, whereby the connection is automatically released.

Abstract: A safety bar mechanism and sheet processing device having a safety bar mechanism, with which such an accident that the operator's hand is pinched between a table and peripheral devices etc. can be positively avoided whatever direction an external force exerts. The safety bar mechanism is disposed, for example, above the table on which a sheet is stacked, and comprises detector means the upper end of which is supported on a fixed part such that the detector means pivots freely in forward/backward directions and has play in upward/downward directions. When an external force works on the detector means, thereby moving the detector means upwards, forwards or backwards, a switching means is so operated as to at least stop the upward movement of the table.

Abstract: A foot pedal safety switch and safety circuit for industrial machines which effectively precludes accidental operation of a machine and improper repetitive cycling of a machine. The foot pedal is completely enclosed within a rigid enclosure having an entry door through which an operator's foot is inserted each time the foot pedal switch is actuated. The safety circuit includes one or more limit switches indicating the status of the access panel and triggering a timing circuit which provides a time period within which the foot pedal switch must be contacted to operate the machine. For a second operation of the machine, the operator's foot must be removed from the enclosure allowing the access panel to close. To repeat operation of the machine, the operator then places his foot again in the foot pedal through the access panel. The safety circuit is mounted within the foot pedal switch enclosure to provide a self-contained single-actuation device which can be easily incorporated into existing machinery.

Abstract: In a ram locking device for securing the ram of a chipless forming machine, more particularly a heavy press, wherein the tool-carrying ram, movable up and down in the press frame relative to the bed of the press, is supported by the head of an axially adjustable tension rod, the unlocking, more particularly the release of the tension rod, is improved if the tension rod is statically cushioned and is automatically pressure-relieved as the release begins.

Abstract: A sensing device for monitoring the presence of a tool or other object on an automatic machine comprises a sensing head adapted to be mounted on the machine. The sensing head has a sensing needle mounted on the output shaft of a reversible motor actuated on each cycle of the automatic machine for movement through a swing angle such that the sensing needle will either contact the monitored object or complete the full swing angle movement resulting in a cycle continue or cycle stop signal to the automatic machine control. The swing angle is manually adjustable by a setting ring on the sensing head for either clockwise or counterclockwise initial rotation of the sensing needle through any desired angle up to 180.degree. degrees.

Abstract: A palm-button control system provides for machinery control with minimized operator hand pressure by use of capacitive switches and reduced susceptibility to radio frequency interference. The system employs first and second capacitive palm-button switches, both of which must be contacted before machinery is activated. Each capacitive palm-button includes a radio frequency sensor which functions to disable machine activation in the presence of a sufficiently strong radio signal. Circuitry for periodically testing the radio frequency sensors provides periodic visual operator feedback indicative of operability of the system. All controls are synchronized or enabled in accordance with a series of digital pulses.

Abstract: A toilet elevation adjusting apparatus having an inner box-shaped frame secured within an outer box-shaped frame by channels and wheels to allow vertical displacement of the inner frame while the outer frame is secured to a wall. A toilet is secured to the inner frame to translate with it. A drive mechanism for displacing the inner frame includes a reversible motor and a safety connection to the inner frame which allows lifting and lowering of the toilet under normal conditions, but disengages the motor from the inner frame when the toilet interferes with an object disposed under it during lowering to prevent exertion of force on the toilet from the motor. Three microswitches are also provided to control the motor operation.

Abstract: A radial arm saw assembly (10) includes a fixed position support (12) and a power saw (22) mounted on the support (12) for reciprocating movement relative thereto. The saw (22) includes a blade (28) and a drive mechanism for powering movement of the blade (28) which forces the power saw (22) towards the user (30) thereof at a predetermined speed when controlled by the user (30). A brake mechanism (38,38',38") locks movement of the saw (22) towards the user (30) when the saw (22) moves faster than the predetermined speed.

Abstract: A safety interlock/latch assembly for use on a printing press having at least one safety latch (100) and one guard element (102). At least one lockable pivot device (106, 116) for allowing rotation of the guard element (102) is attached to a first end (104) of the guard element (102). A roller (112) for engaging the lockable pivot device (106, 116) is provided and has a cam (146) for switch actuation. A support device (132) for rotatably holding the roller (112) is provided and has an aperture (142) with a predetermined configuration for receiving the lockable pivot device (106, 116). The support device (132) is located at least between the lockable pivot device (106, 116) and the roller (112) and is attached to the printing press. A release latch (160) on the support device (132) holds the guard element (102) open and a spring latch (158) on the support device (132) holds the guard element (102 ) closed.

Abstract: The invention relates to an arrangement and method for operating a self-propelled vibratory plate device. The vibratory plate of this device receives its vibratory motion from counter-rotating eccentric parts driven by an internal combustion engine. According to the method, the vibratory plate is stopped with a deadman's handle mounted on the device without the engine stopping. The method is realized with the arrangement of the invention which includes the deadman's handle. The deadman's handle is connected to the engine's fuel control and a centrifugal clutch between the engine and the eccentric parts is engaged only when the speed of the engine is above idle speed. A cam is provided with an interacting support which limits the angular movement of the deadman's handle to a position which corresponds to the idle speed of the engine.

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: A support apparatus for a medical appliance includes a support, a lifter for mounting the medical appliance, a counterweight, a wire with one end connected to the lifter and the other end connected to the counterweight, the wire being passed over a first pulley mounted rotatably on the support, whereby the medical appliance can be moved vertically with weights of the lifter and the counterweight being substantially balanced with each other.

Abstract: In a method and an apparatus for safe-guarding a press (1) by monitoring the press motion, use is made of the fact that the force exerted by the press is an almost invariable function of the position of the upper press platen in relation to the lower press platen. The force exerted by the press is continuously sensed during each pressure stroke by means of transducers (6). The instantaneous value of the force is compared in a monitoring unit (10) with a reference force value, calculated during the first pressure stroke, at each one of the subsequent positions of the upper press platen of the press in relation to the lower press platen thereof. This comparison is repeated for each such position during the pressure stroke. The monitoring unit (10) directly interrupts the press motion if, on comparison, the sensed force value in any position deviates from the reference force value by more than a predetermined amount.

Abstract: A front end loader in the form of a skid-steer loader which includes a power operated working implement and control apparatus that has a plurality of operative positions for supplying power to the working implement and at least one neutral position where power cannot be supplied to the working implement. The control apparatus is capable of being manipulated by the operator of the loader to place the control apparatus in any one of the selected operative positions or the neutral position. An operator restraint member is mounted on the skid-steer loader and has an engaged position for securing the operator to the operator position during operation of the loader and a disengaged position to permit the operator to enter or leave the loader. A locking member is engaged with the control apparatus when the restraint member is in its disengaged position and is disengaged from the control apparatus when the restraint member is in its engaged position.

Abstract: An operator restraint member having two ends is pivotally mounted at each end to a skid-steer loader. The restraint member has an engaged position for securing the operator to the operator position during operation of the loader and a disengaged position to permit the operator to enter or leave the loader. A friction device is connected to one end of the restraint member to retain the restraint member in the rotative position selected by the operator until repositioned. An automatic lock-quick release latch is connected to the other end of the restraint member for selectively locking the seat bar in its engaged position. A locking assembly is engaged with the control apparatus when the restraint member is in its disengaged position and undergoes pivotal movement to become disengaged from the control apparatus when the restraint member is in its engaged position.

Abstract: A front end loader in the form of a skid-steer loader which includes a power operated working implement and control apparatus that has a plurality of operative positions for supplying power to the working implement and at least one neutral position where power cannot be supplied to the working implement. The control apparatus is capable of being manipulated by the operator of the loader to place the control apparatus in any one of the selected operative positions or the neutral position. An operator restraint member has two ends and is pivotally mounted on the skid-steer loader at one of its ends. The restraint member is swingably movable between an engaged position for securing the operator to the operator position during rough ride conditions and a disengaged position to permit the operator to enter or leave the loader. A latch is provided to selectively secure the restraint bar in the engaged position.

Abstract: A safety brake for use on presses that provides a positive stop which is positioned so that its braking surfaces will be engaged if the press overtravels its normal home position due to failure of the standard clutch and brake system of the press. The braking surfaces of the emergency brake are moved to a released position when the press is energized to begin a cycle of its operation. Once the released braking surfaces have passed by each other during the normal cycle of press operation, they are returned to their braking positions so as to preclude overtravel of the press past its home position to any substantial degree if the conventional brake of the press should fail.

Abstract: A tractor control structure is provided including a pivotal flip-up control console that automatically engages a parking brake and shuts off the fuel supply to the engine when the console is moved to a vertical inoperative position. The console is selectively movable to a vertical inoperative position where it is out of the way when the operator is getting onto or out of the operator's seat. Further, the console is movable to a generally horizontal operative position where conventional transmission control handles are easily accessible from the operator's seat. When the console is moved to its vertical inoperative position, a push-pull cable attachment is automatically pushed forward to actuate an on-off valve for shutting off the fuel supply to the engine and thereby making the machine inoperative. A parking brake is also attached to the pivotal console by means of a tension brake cable.

Abstract: A trouble detecting unit in an optical security device intentionally produces a state which is equivalent to a state in which the security system is out of order so as to check whether an emergency stop signal is produced or not and judges that the security system is in order if the emergency stop signal is produced and that the security system is out of order if the emergency stop signal is not produced. This checking is made while the security system need not be in operation. In a press, for example, the checking is made while the press is being lifted from a bottom dead center. A state which is equivalent to the one in which the security system is out of order is produced by intercepting, one by one, signals to light emitting elements or signals from light receiving elements.

Abstract: A fail-safe relay system for use in infrared security barriers or other apparatus producing a sensing signal so as to control the de-activation and permit the re-activation of an interconnected device; such as a machine press. The relay system uses two relays with contacts in series in conjunction with electronic circuitry. Safe-start operation for preventing reactivation of the interconnected device if any unsafe condition exists, including failure of either pair of relay contacts to open when an unsafe condition is sensed, is also accomplished.

Abstract: A rotary power trowel having a safety clutch, a gyroscopic stabilizing ring, blade pitch control, and an adjustable handle. The safety clutch employs a belt tension adjustment to act as a brake on the drive belt when activated either manually or, in an emergency, automatically by a lever on a handle near the operator. When the rotary trowel goes out of control in an emergency, centrifugal force activates the lever and disengages the driving force and acts to brake the belt in less than one turn of the handle. The gyroscopic stabilizer ring lowers the rotary trowel center of gravity and generates a stabilizing effect. Blade tilting is accomplished through a turning knob located at the end of the adjustable handle, which is adjustable to the height of the operator.

Abstract: An arrangement for protecting tools in a hydraulic press against overloading if an object is present in a tool space of the hydraulic press. A displacement switch monitors at least a portion of a path of movement of a press ram with an additional switching device providing an output signal during a predetermined movement of the press ram. A control circuit evaluates a sequence of the output signals of the displacement switch and additional switching device in such a manner that a fault signal is formed when the additional switching device provides an output signal prior to an output signal from the displacement switch. The additional switching device may be constructed as a switch element which provides an output signal in dependence upon a pressure or a speed of flow of a pressure medium in a hydraulic circuit.

Abstract: A system for preventing the free fall of the platen of a vertical molding machine in the event of failure of the connection between the drive rod and the platen. A hydraulic network is employed to enable the movement of the platen. The network employs a counterbalancing circuit to permit raising the rod and platen and for preventing the gravitational fall of the rod and platen. The operation of this hydraulic circuit is controlled by valves which transfer the hydraulic fluid between the two ends of the respective cylinders, and a storage tank (to store the difference in volume between the rod end and cap end of the respective cylinders). With fluid flowing from the cap end of cylinders to the rod end of said cylinders, the platen may descend. With fluid remaining in the cylinders, the piston and platen cannot descend without the fluid being transferred back to the other end of said cylinder by operation of an electrically controlled valving arrangement.

Abstract: A mechanical safety device for the reciprocating plunger in downwardly acting presses such as a downstroke or eccentric type, in which the plunger is connected to the piston rod of the press cylinder or to the eccentric. A stopping rod is immovably fixed on the plunger and extends vertically upwardly from the plunger and through a stopping sleeve rotatably mounted on a housing fixedly retained on the press. The rod and the sleeve have cooperating threads, the threads on the rod being divided into at least two sections and the threads on the sleeve being divided into as many sections as the threads on the rod and being spaced by arcuate surfaces. In a first rotary position of the sleeve, the threads engage with each other for stopping the plunger, and in a second rotary position of the sleeve, the threads are moved out of engagement with each other for permitting movement of the rod through the sleeve and thereby movement of the plunger.

Abstract: Single revolution clutch mechanisms are conventionally employed in machines such as punch presses and the like. Such clutches are usually provided with single stroke mechanisms so that an operator must release the "RUN" buttons before a subsequent cycle can be initiated. The present invention shows apparatus which prevents the initiation of a subsequent cycle of operation whenever the single stroke mechanism comes into operation. A latch is released upon such operation of the single stroke mechanism which prevents operation of the cycle-initiating means by the operator and requires the services of a maintenance man at the clutch mechanism to restore the clutch-iniatiating and single stroke mechanism to operating condition.

Abstract: A press mechanism that is powered by hydraulic, electrical and/or pneumatic means is provided with an improved ratchet and pawl machine which acts as a fail-safe device should any of the power means fail to lock the press parts in place. The fail-safe device includes a ratchet in the form of a circular or arcuate segment mounted with its circular center substantially coaxial with one of the turning parts of the mechanism or press, a pawl having a single tooth and a circular arcuate peripheral part that acts as a journal bearing and which in turn is supported by a pawl bearing which in turn is secured to a stationary part of the mechanism and has an arcuate journal which receives and supports the pawl therein. Tremendous load carrying capacity is thus achieved because of the large bearing area provided by the pawl bearing and the positioning of the respective ratchet and pawl teeth to employ a surface rather than point contact.

Abstract: A chain of the type that is used in a reciprocating chain drive. The majority of the chain is constructed of conventional links that mesh with and are driven by rotating sprockets. A specially constructed link is included in the chain to disengage from the sprockets if the reversal controls of the chain drive mechanism malfunction. The special disengaging link is provided with an inclined plate which cams against the sprocket teeth to divert the chain off to the side of the sprocket if the disengaging link reaches the sprocket due to a control malfunction.

Abstract: A cutter ring operable to sever the blades of a turbine wheel in a gas turbine engine upon failure of a thrust bearing carrying the wheel in the turbine. Severance occurs while the blades are within the confines of a containment ring to prevent fragments from being ejected out of the turbine housing. The cutter also presents a friction pad of high heat absorption characteristics for reducing maximum temperature developed in the engine upon bearing failure.