Abstract: A linear actuator in which the number of limit switches to be mounted, as well as the mounting position and direction of limit switches, can be selected with a high degree of freedom, the limit switch mounting spacing can be made short, and a positive operation is ensured while using a small number of components. Flat limit switch mounting flanges are fixed onto an outer cylinder of a linear actuator so that their positions are adjustable in both axial and circumferential directions of the outer cylinder, and a guide rail for slidably guiding a striker is supported by and between the limit switch mounting flanges. The striker is connected with the actuator rod of the actuator by a connecting rod. With projection or retraction of the actuating rod, the striker moves and actuates limit switches attached to the associated limit switch mounting flanges.

Abstract: A device for detecting a position of a moving body is provided in which a position of a moving body such as a window glass of a power window device can be detected with high accuracy, initial positions can be set without complicated adjustment, such can be realized with a simple structure and at a low cost, and assemblability can be greatly improved. In the device for detecting a position of a moving body, fixed contacts press-contact a flange portion of a ring gear from a side opposite a side at which a cover plate is disposed. Accordingly, the fixed contacts can be installed after the ring gear. In a state in which the ring gear is provisionally installed, press-contact force of the fixed contacts is not applied to the ring gear. As a result, the ring gear does not rise and positional deviation does not occur, and therefore, the assemblability can be greatly improved.

Abstract: A pedestrian crosswalk switch (140) for registering force applied to a crosswalk button (172) is provided. The pedestrian crosswalk switch (140) includes a button housing (142), a crosswalk button assembly (143) including a compression spring (174), a button coupling assembly (176), and a microswitch assembly (178). The crosswalk button assembly (143) has a button shank (184) that protrudes through the compression spring (174) and into a button aperture (162) of the button housing (142). The button coupling assembly movably couples the crosswalk button (172) via the button shank (184). The microswitch assembly (178) has a movable trigger (196) and a compression spring (198) pivotally mounted to a microswitch (194) by a pivot pin (202). The microswitch assembly (178) is mounted to a flange (168) protruding from the button housing (142) such that the trigger (196) is in engaging alignment with the button coupling assembly (176).

Abstract: A device for detecting a change in the thrust load acting on the actuating rod of a linear actuator. The thrust detecting device includes a pinion which converts and enlarges an axial linear displacement of a rotating drive screw shaft caused by a change in the load on an actuating rod driven by the screw shaft into an angular displacement of a vertical shaft of the pinion. A circular scale plate is attached to the vertical shaft of the pinion and serves to indicate a preset value for the load change to be detected. A pair of striker plates each having a pointer effective to select a preset value on the circular scale plate and a striker effective to activate a corresponding limit switch are attached to the circular scale plate.

Abstract: An electric transfer switch includes a linear actuator operable to switch a plurality of movable contacts from a normal power supply to a standby emergency power supply, when the normal power supply has a power outage, so as to continuously serve electricity to electric loads. A plurality of leaf springs and an offset linkage angle help prevent any incidental disconnection between the moveable contacts and the stationary contacts. The transfer switch also includes a magnetic strip. The magnetic strip is magnetized when there is a "fault" current passing by the contact tips of the moveable and stationary contacts. The attractive force between the magnetic strip and the moveable contacts due to the magnetization overcomes the repulsive force caused by the "fault" current so as to make the contact between the moveable contacts and the stationary contacts unopenable.

Abstract: In one aspect of the present invention, this is accomplished by providing a tower that includes a fixed member; at least one movable tower member, the at least one movable tower member is movable relative to the fixed member. The tower also includes a drive for moving the at least one movable tower member when power is supplied to the drive; and a tower position detection system comprising: a switch mounted on the fixed member and electrically connected to the drive, and an actuator member mounted in a predetermined position along the length of one of the at least one movable tower members so that when the one of the at least one movable tower members is in a predetermined location relative to the fixed member, the actuator is located proximate the switch to open the switch and terminate the supply of power to the drive.

Abstract: The present invention is a switch actuating unit having at least one electrical or electromechanical limiting position switch, actuatable by a mechanical sensing device. This unit structurally combines the mechanical sensing device and the electrical switches such that the switches are activated in at least two limiting positions by a common actuating plunger. The plunger extends from either side of the unit and actuates the switches upon engagement with a stop or flange plate defining each of the limit positions. Furthermore, the sensing device and switches are structurally combined so as to be moveable together.

Abstract: In a limit switch, its rotational operation section B includes a rotary shaft 9 which is rotatably supported on a head housing 5, and an actuator 10 for turning the rotary shaft 9, and its switch section C comprises a detector 29 which is built in a switch housing 3, to detect particular detection parts 27a and 27b in a non-contact mode which are provided on the outer cylindrical surface of a cam 25 mounted fixedly on the rotary shaft 9, thereby to provide a detection signal. The head housing 5 and the switch housing 3 are formed as one unit. A limit switch which is simple in construction, has a small number of components in comparison with the conventional limit switch, can be miniaturized, has a long service life, and is reliable in operation, is provided.

Abstract: A microtome (2) with a sample holder (51) for a sample (22) to be thinly sectioned and with a knife holder (12) for a cutting knife (10) is described, wherein the sample holder (51), for performing a cutting movement (arrow 54) relative to the knife holder (12), can be driven in a first spatial direction (arrows 54, 56) by means of a first drive device (53), and for performing a coarse adjustment and a section thickness adjusting movement in a second spatial direction (arrow 24) perpendicular to the first spatial direction (54, 56) by means of an electrical second drive device (50). In the vicinity of the cutting knife (10), for defined delimitation of the coarse adjustment movement of the sample holder (51) in the second spatial direction, a delimiting device (20) is provided, which is connected over control means (44), preferably an electronic control, with the electrical second drive device (50).

Abstract: A self contained limit switch assembly includes a gear box containing gears which mesh with a gear mounted on the shaft of a rotor. The gear box gears drive a cam. Limit switches, which are operatively connected to the motor's control circuit, are placed in the path of the cam to be actuated thereby. The limit switch assembly includes a housing which may be applied to an end shield of the motor, allowing the limit switch assembly to be applied optionally to any motor which may be incorporated into a product which requires use of a limit switch in the product's operation.

Abstract: A system for detecting a limit of acceptable rotation for a joint is disclosed. The system includes a support that supports the joint and keeps its pivot point substantially stationary with respect thereto. The system also includes an extensible leg connected to the joint. A contoured member is mounted adjacent the extensible leg and has a surface shaped as a portion of a sphere. The contoured member is located so the pivot point of the joint substantially coincides with the center of the sphere and the periphery of the contoured member corresponds to the limit of acceptable rotation for the joint. Thus, as the leg pivots, the contoured member also moves a similar amount. A detector is used to detect the periphery of the contoured member surface and to assist in preventing further rotation of the joint in that direction.

Abstract: A rectangular cavity is provided in an actuator lever intersecting with an upper edge of a shaft-receiving hole in the lever and receives a linearly slidable hard metal rectangular key having a cam on one edge for clamping the lever to the shaft. A screw engages threads on the key and is slidable with the key to a position where a distal end of the key is flush with or projects from a side surface of the lever, at which position the cam is free of the shaft-receiving opening, the key providing visual indication that the lever assembly may be positioned over the shaft without interference.

Abstract: In a limit switch, its rotational operation section B includes a rotary shaft 9 which is rotatably supported on a head housing 5, and an actuator 10 for turning the rotary shaft 9, and its switch section C comprises a detector 29 which is built in a switch housing 3, to detect particular detection parts 27a and 27b in a non-contact mode which are provided on the outer cylindrical surface of a cam 25 mounted fixedly on the rotary shaft 9, thereby to provide a detection signal. The head housing 5 and the switch housing 3 are formed as one unit. A limit switch which is simple in construction, has a small number of components in comparison with the conventional limit switch, can be miniaturized, has a long service life, and is reliable in operation, is provided.

Abstract: A monitoring device is provided for use in association with a limit switch or similar mechanically actuated device in order to permit its end of life to be predicted. The system uses nonvolatile random access memory to store a count which represents the number of occurrences of one of two alternative events. The first event is the occurrence of a number of switch actuations and the second event is the lapse of a predetermined period of time. When either of these two events occurs, a microprocessor increments a count in the nonvolatile memory unit and clears both the clock and the volatile memory parameter. When the number stored in the nonvolatile memory represents a number of actuations estimated to be appropriately equal to the total life of the switch, this condition can be signaled to a sensor bus by a communication circuit. Alternatively, a light emitting diode can be alternately energized and de-energized to represent the number of actuations having exceeded the predicted end of life total.

Abstract: A mechanical device forms part of a limiter assembly associated with reversible electric actuators. Typically, such an actuator is for controlling pipeline valves. The limiter assembly comprises a mechanism by which one or more limiters can be held in the engaged position even after the trigger has been deactivated. The undesirable phenomenon of hunting or pumping (the effect of the actuator motor cutting in and out repeatedly) is prevented by a simple flexible ribbon with teeth positioned in such a way as to engage corresponding sprockets that are capable of rotation on their respective shafts in only one direction.

Abstract: A compact automatic stop device for two mechanisms for counting revolutions which consist of coaxial counting wheels (10, 10') each associated with a notched cam (14, 14') interacts with a cutoff finger (24, 24') securely fastened to a common cutoff lever (20, 20'), so that when the notches (19) are aligned, the cutoff lever actuates a switch (26, 26'). A set-to-zero lever (29, 29') makes it possible to reset the counting wheels to zero by acting via hammers (33') on core cams (18'). The counting wheels, the cutoff levers and the set-to-zero levers of each counting mechanism are pivoted in a common cradle (5, 5') articulated with respect to a fixed casing (1) having profiled parts (36, 37, 36', 37') which are intended to interact with the cutoff levers and the set-to-zero levers during the displacement of the cradles.

Abstract: A limit switching apparatus with defined overtravel for specimen-objective protection on microscopes having a motorized focusing drive. A stored focus position or position of the specimen stage can be overtraveled by a fixed amount. The maximum travel path of the specimen stage is additionally limited by a switching rod and a short-circuiting switch, in order to ensure reliable specimen-objective protection even in the event of a fault in the control electronics.

Abstract: A cam follower disposed on a limit switch utilized in elevator systems comprises a tire and a hub. The tire comprises a torus and a web, wherein the web includes a plurality of elongated slots that allow free movement of the tire within the hub. The hub comprises two portions that snap fit together securing the tire therebetween so that when the tire of the cam follower is impacted, the tire absorbs the impact shock and minimizes noise caused by the impact. The cam follower design also allows an inexpensive fabrication and assembly.

Abstract: An elevator limit switch is constructed of molded plastic box and lid and is readily adaptable for left side or right side use on an elevator or an elevator hoistway. The box and lid hold a one piece plastic hub which carries a mounting system for holding readily reversible electrical contacts.

Abstract: An output torque sensing and limiting mechanism, for preventing the continued application of torque to a load when the torque exceeds a selected value. The mechanism is positioned at the end of a gear train, meshed with the final gear and adapted to transmit the output torque to the load, through an output adapter. An input gear assembly includes a sector gear, meshed with the gear train, for receiving the input torque. A housing assembly is rotationally carried on the input gear assembly, with wing members extending to define a wing angle. The sector gear lies in the wing angle, with vertical gear ends adjacent each wing member. A torque sensor subassembly is carried in each wing member, consisting of a bearing button positioned in registration with the sector gear end, biased into position by a wave spring and adjustable by means of a retainer button. Microswitches are carried on the sector gear, located with the switch elements extending into the gap between the sector gear and each wing member.

Abstract: A side mount garage door operator capable of being positioned on either the ceiling or end wall of a garage at either side of the garage door on a frame unit, the operator providing a clutch for disengaging the drive motor from the garage door in the absence of electric power and having a manual graspable handle operated by a solenoid when power is present and operable manually in the absence of power. Novel limit means having limits which is on the end of an axially movable bar which is moved by a follower riding in a spiral groove in the base of a disk such as a gear connected to the drive shaft.

Abstract: A limit switch is disclosed which comprises an operating lever, a rotary shaft which is driven by the operating lever, a first cam and a second cam as mounted on the rotary shaft for transformation of rotary motion into linear motion, a return spring for applying a returning force to the operating lever through the rotary shaft, a plunger operatively associated with the cams for turning a basic switch ON or OFF and a plunger holder for holding the plunger axially movable but not rotatable. The plunger having a plurality of integral projections corresponding to cam projections of the respective cams and disposed between the cams. The plunger is rotatable about its axis through the plunger holder to switch the ON-OFF mode of the basic switch.

Abstract: A ball bearing plunger actuator for a limit switch is provided with an insert between the ball bearing and the actuator. The insert is disposed into an opening in the distal end of the actuator before insertion of the sphere. After swaging the sphere is captivated within the opening of the actuator with the low friction insert disposed at the bottom of the opening between the sphere and the actuator. In a preferred embodiment of the present invention, the low friction insert is made of a fluorocarbon, such as TFE. Several embodiments of the present invention incorporate inserts which are differently shaped to provide certain advantages in particular adaptations. Two of the embodiments utilized either a generally cylindrical insert with a conical concave part of the insert shaped at one end to receive the ball bearing or, alternatively, a generally flat circular disc of fluorocarbon material which conforms to the bottom of the opening and is inserted into the opening prior to insertion of the sphere.

Abstract: A switching device which uses a pivotable switching element carrying a first magnet and a movable component carrying a second magnet mounted adjacent thereto, the north and south poles of the magnets being arranged so that, when the movable component is moved to a first location, the magnets attract and the pivotable element is in a first switch position and, when the movable component is moved to a second location, the magnets repel and the pivotable element is in a second switch position.

Abstract: An air control damper assembly for mounting in an air duct comprising a damper blade pivotally mounted within the air duct and means for rotating the damper blade from an open position to a close position. A drive system rotates the damper blade such that the system exerts a high torque and low speed at the beginning and end of the rotation of the blade from one position to the other and a low torque and high speed in the middle of the rotation of the blade between positions. The damper blade is locked in the open and close positions by means of a motor and gear unit. Electrical switches interfacing with a drive disk in the drive system partially controls the energization of the motor.

Abstract: A limit switch unit suitable for use in a passive seat belt system of the type that a movable anchor with a webbing connected thereto is moved by a drive member such as a drive wire along a rail between an occupant-restraining position and an occupant-releasing position. The limit switch unit is composed of a guide for introducing the drive member into the rail and a limit switch for detecting the arrival of the movable anchor at the occupant-restraining position or the occupant-releasing position. The limit switch is integral with the guide, whereby the limit switch unit is formed. A passive seat belt system with the limit switch unit incorporated therein is also disclosed.

Abstract: A control device for stopping and/or starting plate saws, for a plate saw having at least one workpiece support table operably associated therewith. An actuation member is provided which is accessible to an operator positioned adjacent the workpiece support table or behind it, or between two or more tables. The actuation member is a bar-shaped member, rotatably supported about an axis extending beneath and parallel to a longitudinal edge of a table surface of one of the workpiece support tables.

Abstract: Disclosed herein are phthalonitriles of the following formula: ##STR1## wherein R.sup.1, R.sup.2, and R.sup.3 are independently in each occurrence an aryl or phosphazine group; X is independently in each occurrence O, S, S(O), S(O)(O), P(R.sup.5), P(O)(R.sup.5), or N(R.sup.5); R.sup.4 is independently in each occurrence aryl, aryloxy, polyhaloaryl, polyhaloaryloxy, polyhaloalkylaryl, or polyhaloalkylaryloxy; R.sup.5 is independently in each occurrence aryl, polyhaloaryl, or polyhaloalkylaryl; n is a number from 1 to 4; and m is a number from 2 to 5. Also disclosed are phthalocyanines prepared from the above-described phthalonitriles. Also disclosed is a lubricant composition which comprises a lubricating fluid and a phthalonitrile or phthalocyanine as described above.

Abstract: A limit switch comprising a case housing a switching unit, a head secured to one end of the case, a rotary shaft rotatably supported by the head and having a flat portion, a manipulation lever secured at a butt end thereof to the rotary shaft which supports at a tip end thereof roller means for detecting an object, a return coil spring provided in the head which applies a force through a return plunger to the flat portion of the rotary shaft to return the manipulation lever to a free position, a disk cam secured to the rotary shaft and having a projection formed on a peripheral portion thereof in a position corresponding to the free position of the manipulation lever, manipulation plunger means for the switching unit which is driven in response to rotary movement of disk cam and elastic stopper means disposed in the head for contacting the projection of disk cam and for braking the manipulation lever when manipulation lever is returned to the free position, whereby the lever is prevented from being swung back

Abstract: A limit switch assembly for mounting on mobile storage units has first and second limit switches secured in spaced relationship. A switch operating rod is spring biased to extend from the assembly by a predetermined amount into an open aisle or where there is no proximate storage unit and there is a cam element on the rod which holds the first switch in closed circuit condition to enable a motor on the unit and drive it into the open aisle space and when the rod touches a stop as the unit means reaches the limit of its travel the cam shifts to open the first switch to initiate a deceleration interval which terminates when the cam retracts enough to open the second switch which disables the motor.

Abstract: A lever (6) is pushed by a cam profile (23) formed on an actuating member (9) fastened to a movable body (12), the movement of which is to be detected. A cam (13) fixed to the lever moves a plunger (16) which actuates a position switch (33). There is interposed between the plunger and the switch an influencing member (22), the position of which is measured by means of a card (28) passing in front of photoelectric detectors (29). A processing unit (31) supplies, at the output, an analog or numerical signal relating to the position of the movable body (12), to its speed or to its acceleration.

Abstract: A limit switch having a fixed casing, an actuating part moveably support by the casing, and a pair of contact sets which are adapted to be activated by the movement of the actuating part, one for producing a normal switch output and the other for producing a stroke signal which serves as data for evaluating the appropriateness of the stroke of the actuating part. The other contact set may produce a signal when the actuating part has moved a certain distance more than the minimum stroke for activating the first contact set. Thus, the output from the second contact set ensures a certain stroke margin of the actuating part. Further, the second contact set may produce another stroke signal when the actuating part has been displaced close to the maximum permissible stroke of the actuating part so that an excessive stroke of the actuating part may be detected. The contact set may be purely mechanical or may also be a combination of a mechanical switch and a photoelectric switch.

Abstract: A self-setting switch-actuating assembly includes a pair of cam members and a rotational motion transmitting shaft. The cam members are mounted on the shaft. The shaft is rotatably mounted between a pair of switches and is connected to a rotatable device whose rotational movement will cause rotation of the shaft and will stop in response to reaching angularly-displaced limits. The cam members are mounted on the shaft one above the other with each cam member aligned with only one of the switches and movable along a rotational path toward and away from a predetermined actuating position relative to its aligned one of the switches in response to rotation of the shaft. Also, each cam member is mounted on the shaft so as to be capable of stopping movement in response to reaching its predetermined actuating position and relative to continuing rotation of the shaft thereby permitting a predetermined degree of overtravel of the shaft relative to each of the cam members at their respective actuating positions.

Abstract: An adjustable mounting assembly for a limit switch is disclosed which includes a stationary H-shaped base plate attachable to a machine table, a movable plate slidably mounted on the base plate upon which a limit switch is carried, an adjusting screw interconnecting the plates, and locking screws which are inserted through elongated slots in one of the plates into threaded holes in the other plate which lie along the centerline of the slots for locking the plates together once the desired position of the switch has been obtained. The assembly is adaptable for moving the switch along its longitudinal centerline, along a line parallel with the table and perpendicular to its longitudinal centerline, or in a direction normal to the table and perpendicular to its longitudinal centerline. The movable plate contains at least one tab which projects into one of two outwardly opening slots in the base plate which are separated by a cross member.

Abstract: A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44,46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (74) mounted for sliding movement over a relatively short distance sufficient to move two actuating targets (104,106) into an out of actuating proximity of respective air core proximity sensing coils (132,134) within the housing. Lost motion abutment structure (76,78) on the switch actuation member and power driven member (54) move into engagement with each other as a power driven member approaches each end of its stroke.

Abstract: There are provided a first switch which is switched to the on state or the off state in association with a displacement of an actuator which causes a displacement by a contact with an object and a second switch which is switched to the on state or off state later than the first switch in association with the displacement of the actuator. A switch output is produced and an abnormality is detected in accordance with the on and off states of these switches.

Abstract: A proximity switch for signaling the location of a movable member at either of opposite end limits of movement relative to a stationary frame includes a movable member, such as a piston, traveling along a fixed path of movement between a first position and a second position and having an aperture formed within the movable member extending from one end toward another end. A housing encloses a portion of the movable member to form a first fluid chamber between the movable member and a first end of the housing, and to form a second fluid chamber between a second end of the housing and the movable member. Expansion of the first fluid chamber drives the movable member to the first position and expansion of the second fluid chamber drives the movable member to the second position.

Abstract: An overload protector for a robot arm has an open-topped cylinder into which a piston is inserted. The piston is held against a circumferential stop surface of the cylinder by compression springs.

Abstract: A limit switch includes a housing which encloses a snap switch having first and second pairs of spaced fixed contacts and first and second movable contacts supported on a carrier and operated by first and second reciprocating plungers that are biased to a first position. Toggle springs are interposed between the respective plungers and the carrier to move the carrier and the associated contacts between fixed pairs of fixed contacts during reciprocation of the respective plungers. An actuator head is mounted on the switch housing and has cams for actuating the respective plungers.

Abstract: An electric position indicating apparatus includes a base structure which accommodates a central reciprocating element is provided with a control mechanism for determining the position of the reciprocating element. Connected to the base structure is a component carrier the walls of which support the control mechanism with its control elements, clamp terminals and circuit boards. The walls of the component carrier are directed toward the corners of the base structure with the control elements supported at one side of the base structure and the clamp terminals at the opposing side thereof.

Abstract: Robot joint with an electric drive motor (30), a limit switch (36) for a safety shut off of the same, and a sensor (100) for the zero position-scanning of the joint. The limit switch (36) is actuated by annular segment like platform pieces (50) which are securable in different angle positions on a front face of the one robot part (12). For this purpose, a divided support ring (72,74) is provided which is securable in different angle positions independent from the platform pieces (50) and which has a side face (96,98) which influences the sensor (100).

Abstract: A motor operator for local or remote shifting of switchgear contacts toward either open or closed positions includes a reversible motor and rotatable drive screw mounted on common support structure for simultaneous pivoting movement as a drive nut translates fore-and-aft along the length of the screw. The drive nut includes an outer body and an inner sleeve which is set into free-wheeling motion whenever the sleeve comes into contact with either of two stops mounted on the screw defining respective end limits of travel for the nut. A drive element normally coupling the nut to an operating shaft of the switchgear is removable to allow the shaft to be manually rotated with a wrench when desired, and removal of the drive element reduces the likelihood that the worker is injured upon unintentional activation of the motor while the operating shaft is turned by hand.

Abstract: An improved shift motor assembly for selectively moving a shift rod or similar member between two gear-engaging positions for use, for example, in a two-speed axle assembly is disclosed. The assembly includes a mechanism for limiting the amount of linear movement of a drive nut of a gear changing apparatus. The movement limiting mechanism interrupts an electrical circuit between a source of electrical energy and a bi-directional motor utilized to move the drive nut, thereby preventing linear movement of the drive nut beyond predetermined limit positions in either directions. The movement limiting mechanism includes a movable electrical contact which normally engages a stationary electrical contact. The movable and stationary electrical contacts form a single pole, single throw electrical switch which is connected in series between the source of electrical energy and the motor.

Abstract: A protective device for a feed unit, especially for a spindle sleeve of a measuring machine, whereby the feed unit is surrounded by a jacket constituted of a multiplicity of springs, which touch the feed unit in the event of a collision and thereby produce electrical contacts, and in which the lower or bottom part of the feed unit is enclosed by a protective shield. The protective shield is constituted of individual screen parts which are displaceable or swingable out of their inoperative position, and which collectively enclose the lower part, wherein the screen parts are maintained in their inoperative position by means of magnets, and in which the screen parts in their tilted position touch at least one spring and thereby become electrically contactive.

Abstract: A limit switch includes a casing, a switch mechanism housed in the casing, a cover covering the casing, and an actuator mounted in the casing for operating the switch mechanism, the cover having a curved or partly spherical convex surface. The cover has at least a transparent or semitransparent portion, and a rating plate is disposed against a back of the transparent or semitransparent portion of the cover. The curved or partly spherical convex surface of the cover prevents spatter expelled from a welding machine from being deposited thereon. Since the spatter is not deposited directly on the rating plate, indications on the rating plate and the energization of an operation indication lamp within the cover can reliably be confirmed.

Abstract: A switch assembly comprising an actuator plunger for actuating a built-in switch, a rotary shaft for rotating in response to an external operating force, and a cam coupled to the rotary shaft and adapted to contact the actuator plunger, the actuator plunger being adapted to be moved upwardly or downwardly in response to a rotation of the rotary shaft through the cam so as to switch the built-in switch, and the cam having a hole to provide a predetermined free angular play between the rotary shaft and the cam as assembled.

Abstract: A precision subminiature, snap action switch and an externally actuated, heavy duty, spring loaded self-return type operator therefor are enclosed within an hermetically sealed housing. The operator employs a switch actuating cam having shoulders cooperable with shoulders on the interior of the housing to define the limits of cam movement, said cam also having a shoulder cooperable with a shoulder on a switch lever to trip the switch upon movement of the externally actuated operator shaft a precise amount away from its at rest position. A connector/switch subassembly sealingly closes a housing opening, provides a rigid, precision mounting for the switch, and also provides external electrical connections for the switch.

Abstract: A permanent magnet DC motor-driven linear actuator has a screw shaft supported against axial movement by a compressed spring. Excess thrust in one direction causes the shaft to move axially to open a first momentary switch, and excess thrust in the opposite direction similarly opens a second momentary switch. The switches are connected electrically in series with each other and with the motor, and enable the motor to stop whenever a mechanical overload is encountered regardless of the position of the actuator operating rod. Diodes connected across the switches in opposite directions allow reversal of the motor by reversing polarity of the DC supply, even when a switch is held open. In two of the embodiments of the invention, the swithes are double-throw switches, and additional diodes are connected from the normally open contacts of the switches to the opposite terminal of the motor to provide dynamic braking.

Abstract: A drive mechanism comprises a support upon which a drive member is mounted for movement relative to a frame. The drive member comprises first and second elements which are relatively movable, the one of which may be mounted on the other. The elements are interconnected by a resilient member which transmits the drive therethrough, a drive input being coupled to a one element, a drive output to the other element. A detector generates a signal output responsive to relative movement of the elements which may serve to control a drive transmitted through the mechanism. In a preferred embodiment, the support is a rotatable screwed shaft and the first element a traveller thereon upon which the second element is slidably mounted, the elements being interconnected by helical springs.

Abstract: An electric safety device for controlling a power switch 8 and a grounding switch 9 of a high voltage electric device includes a motor 10, a threaded shaft 4 driven by the motor, a movable sleeve 5 on the threaded shaft for being driven by the motor to and fro, and a pair of rotary members 6, 7 each of which includes a wheel 62, 72 having a recess on its periphery, a rod 61, 71 axially extending from its center, and a U-shaped guide piece 63, 73 radially extending from the rod. The rods are parallel to one another and are disposed near the shaft perpendicularly, and the guide pieces are movable one after the other through 90.degree. when pushed by the sleeve to cause the rods and the wheels to rotate. The periphery of one of the wheels cams the power switch off and the periphery of the other wheel thereafter releases the grounding switch when they rotate to safely enable maintenance work.