Abstract: A device for stripping a fibrous web from a doffer in a carding machine comprising a doffing roller for directly stripping the web from the doffer, a guide roller for guiding the web and a punched suction roller provided adjacent to the guide roller for feeding the web to a collector in combination with the guide roller. All the rollers are placed in mutually adjacent, parallel relation and are positively rotated. Within the punched roller, there is provided a stationary duct which is connected to a source of negative pressure. The duct includes an elongate suction port having a length corresponding to the effective length of the punched roller. The suction port faces the space between the punched roller and the guide roller. Air is drawn into the duct through a multiplicity of holes in the punched roller to prevent winding of the web around the doffing roller and the guide roller and remove waste fibers and impurities from the web.

Abstract: An apron clearer attachment is illustrated having disengagable mounting means carried adjacent one end thereof for positioning the clearer attachment upon a pivotal mounting adjacent a sliver guide which introduces fibers to an apron assembly. The apron clearer attachment is weighted and carries a clearer pad for maintaining the apron free of extraneous fibers, dirt and the like, which may tend to adversely affect the yarn being manufactured.

Abstract: This invention relates to a jewelry clutch for securing articles together, the clutch including releasably connected male and female components. The male component comprises a pin and the female component comprises a retainer located in a carrier. The carrier is positioned in a housing for releasably clamping the pin. When joined, the pin cannot be separated from the retainer except by depressing the carrier into the housing.

Abstract: A coupling for connecting one end of a strap to a musical instrument or other body consists of a post fixed to the instrument and a catch fixed to the strap and cooperable with the post. The post has an enlarged head which is movable laterally into and out of a cavity in the catch. When the post head is received in the catch cavity a spring biased plunger of the catch enters a central opening of the post to prevent the catch and post from moving laterally out of assembly, while nevertheless permitting the catch and the associated strap to pivot or swivel relative to the post. The plunger is movable by hand out of the path of the post head during connection and disconnection of the post and catch relative to one another. Further, the two coupling parts can be quickly and easily connected and disconnected relative to one another with one hand of the user and without requiring extremely precise movements.

Abstract: An apparatus for producing velvet having an appearance similar to that of a woven velvet wherein slubbed yarns are used in the weft. The apparatus includes a non-contact heater for heating the pile of a fabric which is then pressed against a cool pattern roll where it is cooled to permanently set the pattern into the pile.

Abstract: An improvement is disclosed in apparatus for copy-machining a workpiece from a master model, the apparatus being moved along the workpiece by a feed mechanism in response to the scanning of the master model. The improvement comprises a first tool and a second tool mounted on the feed mechanism, a pivot arm for supporting the second tool for movement relative to the first tool in the direction of movement along said workpiece, and means for locking said pivot arm and second tool at a desired position, said first and second tools engaging the workpiece in staggered relationship to one another, with reference to the direction of movement along said workpiece, wherein the relative positions of said first and second tools are adjustable by movement of the second tool in response to movement of the pivot arm and locking the pivot arm and second tool at the desired position. Apparatus is also disclosed wherein the pivot arm is situated substantially orthogonal to the direction of movement along said workpiece.

Abstract: Mesh distribution wheel for handling seine lines or like net materials. The wheel is provided with a series of pins directed radially outwards which are adapted to engage respective meshes in a series of meshes in the seine line or like materials. The pins are arranged in series with a mutual pitch corresponding to the number of divisions of the series of meshes at a definite degree of mesh inlay. At any rate when regarded in the one lateral direction, the pins have a saw-toothed course from foot portion to outer portion. Adjacent their root portions, each pin has a definite cross-section or one defined together with a neighboring pin which corresponds to the area of a mesh opening in a mesh having a definite mesh size and definite mesh form.

Abstract: A roll assembly for use in rolling a wire rod includes an arbor which has a slightly tapered periphery at the middle portion thereof, a liquid pressure applying channel provided in the arbor extending to the tapered periphery, a cemented carbide sleeve securely fitted about the tapered periphery, opposing tightening means securely holding the sleeve by constricting it at around both ends, and a roll neck bearing mounted around each end portion of the arbor.For assembling the roll assembly, liquid pressure is applied through the channel provided in the arbor so as to form a liquid layer between the sleeve and tapered periphery of the arbor.

Abstract: A heat exchanger assembly and method for making the assembly. The assembly includes a pair of plates having longitudinal grooves which are joined together with the grooves mating with each other to define fluid-carrying channels extending between the ends of the plates for receiving a heat exchange fluid. The plates include an engaging intermediate surface between certain channels and the fluid-carrying channel passages may be arranged in groups having a laterally spaced relationship from each other. Header means having orifices for connection to the fluid-carrying channels are at each end of the plates for providing a continuous closed path. The plates and channels are coiled to extend about and around one of the header means which provides a circular configuration. The grooves in one of the plates include bosses for providing self-spacing of adjacent convolutions of the channels and plates.

Abstract: A spring installation tool for article loading machines is provided to facilitate the application of a biasing spring to sets of guide fingers. Fundamentally, the invention includes an elongated frame member having a tubular portion at a first end thereof for receiving the biasing spring. A rod is provided having a ring at one end which encompasses the tubular portion while being maintained in spring-biased engagement at an opposite end thereof with a second end of the frame member. The rod is operative for reciprocating movement with respect to the frame member to effectuate forcing of the biasing spring from the tubular portion. In use, the tubular portion, bearing a biasing spring, is placed over the end section of a set of guide fingers and the rod is reciprocated to force the spring from the tubular portion into securing and biasing engagement with the fingers.

Abstract: There is disclosed a technique for tightening threaded fasteners in which values of offset torque, initial tension rate relative to angle, final tension rate relative to angle and other joint related factors are empirically determined by instrumenting a plurality of fasteners of the type ultimately to be tightened. In one embodiment, torque and angle are monitored during tightening. Calculations are conducted, while tightening, to determine the tension prevailing in the bolt at a particular angle of advance. By using the calculated tension value and the particular angle of advance, an instantaneous position of threading advance on the tension-angle curve of the fastener is established. From this instantaneous position, it is determined how much greater angle of advance or how much torque is required to tighten the fasteners to a final desired tension value. The same technique may also be used merely to monitor tightening which is terminated by a different tightening strategy.

Abstract: An apparatus is described for pulling the pilot bearing from a flywheel or the like comprising a support member having a pair of spaced-apart bolt members threadably mounted therein. The support member has a central opening formed therein between the bolt members which receives a pair of pivotally mounted first and second jaw members having bearing engaging portions at one end thereof. The jaw members are extended through the central opening in the pilot bearing and then locked into position by means of a smaller bolt extending through the jaw members to limit the pivotal movement thereof. Threadable rotation of the first and second bolt members causes the jaw members to pull the pilot bearing from the flywheel.

Abstract: A method is disclosed whereby the exterior of an older bus can be refurbished and modernized to incorporate both the design features and certain advantageous mechanical functions inherent in modern bus exteriors. The method involves the stripping away of the old monocoque exterior sheathing of the bus, together with the windows, the emergency door, and the front and rear sheathing beneath the windshield housings, then building up a framework of skin support structure between the sheathing support beams, stretching a skin across the sheathing support beams and tack welding it into place against the new framework. New style windows are inserted into place and a new, modernized emergency door is installed.

Abstract: Slide fastener elements, mounted on a longitudinal support member woven in the edge of a tape, are removed by cutting the longitudinal support member on each side of each fastener element and pulling the tape longitudinally between opposed biased blades engaging the elements to strip the fastening elements from the tape.

Abstract: The present invention relates to a tool shifter which performs three kinds of operations, namely, grasping and releasing of a tool, changing of the attitude of a tool and inserting a tool into and removing a tool from a tool magazine by a single hydraulic cylinder for a machine tool the axis of the tool in the tool magazine being disposed at an angle to the main shaft of the machine tool.

Abstract: A method of manufacturing a closed gate MOS transistor having a self-aligned drain contact is presented which insures that the drain contact will have the minimum required geometry. The method employs a self-aligned procedure which insures that the drain contact will have the minimum dimensions to insure a high speed device.

Abstract: Apparatus and method for automatically assembling elastic bulbs to fragile tubular elements, such as the bulbs and pipettes of medicine droppers, in which a bulb and a tubular element held in axial alignment in a fixture are assembled by pressure exerted on the tubular element in the direction of the longitudinal axis of the tubular element, including means for automatically inserting said bulbs and tubular elements in said fixture and aligning the same as aforesaid.

Abstract: An assembly apparatus which is particularly useful in the manual assembly of circuit carrier plates with electrical components is formed with an upwardly facing working surface having thereon a support member for the carrier plates, with a plurality of receptacles for holding components to be mounted on the carrier plates being operatively located beneath the working surface. The receptacles are supported for guided movement beneath the working surface through an uppermost and lowermost plane and an opening in the working surface is provided through which an operator seated at the assembly apparatus may grasp components from receptacles located in the upward plane for mounting upon a carrier plate supported on the support member.

Abstract: An improved assembly table for assembling conductor boards wherein integrated circuits to be inserted on the boards are conveyed by trays automatically and in a synchronized manner from a rotatable magazine to the conductor boards. The integrated circuits are contained in predetermined arrangement in the magazine and are picked up one at a time by a transfer means and each integrated circuit is deposited in an associated tray with a recess shaped to accept the integrated circuit. This arrangement permits safe direct picking up of the integrated circuits with assembly tongs within short reach of the conductor boards.

Abstract: The method for creating an environmental seal for the end of a severed multiconductor cable and for sealing the joints between the conductors of such cable with the contacts of a multiple contact connector into which such cable is inserted. A tape of a soft, pliant material is coated on both sides with a flowable, pressure-sensitive adhesive and is formed into a blank which can be adhered to the cable in various ways. In a first form, the blank encompasses the severed end and portions of the cable adjacent the end. When the connector into which the cable has been inserted is compressed, the adhesive is displaced to seal the contact-conductor joints. Folded-over end flaps seal the cable ends. A midspan use of the blank permits the joints to be sealed without reference to the cable end.

Abstract: The present invention relates to the connection of insulated electric wires, and it pertains more precisely to a terminal and a connection block for electrically connecting two insulated wires without prestripping them. Prior art connecting devices that operate without prestripping are usually in the form of a flat spring, cut in a U shape, the branches of which define a slot. In such devices, the insulated wire to be connected is introduced at the end of the slot adjacent the free ends of the branches. This type of device has a disadvantage since the perforation of the insulation is made where the deformation of the branches is the easiest. The self-stripping connecting device of the present invention is constituted by a flat spring including a portion forming a U, the branches of which are elastically biased one against the other, and an opening to allow the introduction of the insulated wire at the end of the slot adjacent the base of the U.

Abstract: A shaver includes a housing and a shaving head detachably secured to the housing. A modular cutting assembly is detachably mounted in the shaving head and includes a plurality of blades that are reciprocated within the head for cutting hair. The blades are joined together by pins and releasably secured to a mounting block. A biasing element secured between the mounting block and the blades biases the blades away from the mounting block to provide a floating connection. The mounting block is slideably positioned on a clip that is resiliently positioned within the shaving head. The shaver also includes a modular clipper assembly including a pair of blades reciprocally mounted within the shaving head. A clipper guard is slideably mounted in the housing for movement toward and away from the clipper blades and includes at least one sloped slot and a cutout portion with an inclined edge including at least one detent.

Abstract: A folding blade knife in which the blade is held in the open position by a tumbler spring movable in the same plane as the blade and a lock spring movable in a plane perpendicular to the plane of blade movement. The lock spring is mounted in the handle remote from the blade, is movable in a plane by operation of a handle-projecting spring extension and constrained to move in planes perpendicular to said plane by restraining frame piece slots.

Abstract: A rotary cutting assembly with an automatic filament feed. The assembly includes a driven member which is coupled to a drive source and contains a storage spool for the cutting line. The line or filament is automatically advanced from the spool upon displacement of the same through engagement of a ground engaging hub with a surface. Such displacement causes operation of a ratchet means mounted in part on the movable spool or associated therewith and in part on the driven member to permit a limited rotary displacement of the spool within the driven member during rotation of the driven member.

Abstract: A perforating device for wallpaper pieces to be separated from a wall includes an elongated handle and a pair of elongated rollers supported on the handle for free rotation by means of a frame rigidly connected to the handle and carrying axles to support the rollers. Each of the rollers has a plurality of spikes on its periphery which are equally spaced from each other. The rollers are inclined to each other at an obtuse angle so that during the reciprocating motion of the device over the surface to be perforated the spikes will have respective components of movement lengthwise and inclined to the direction of reciprocation and perforate the wallpaper in form of elongated holes to thereby permit a solvent to penetrate through the holes and reach the rearside of the wallpaper.

Abstract: A measuring apparatus in which two casings are connected together each housing a coiled measuring means adapted for being selectively un-coiled and withdrawn from the casing or recoiled and retracted into the casing. A sighting device is provided on one of the casings to sight a target. The sighting means includes a level for determining when the sighting device is sighting along a horizontal line and a second level is provided to indicate when the casings are also appropriately arranged relative to a vertical line perpendicular to the first said horizontal line. Triggers are provided for the two coiled measuring devices and a brake is provided for each of the measuring devices. A digital display is employed and a counting circuit is provided for indicating the amount of measuring means which is uncoiled from the two respective casings. An alarm is provided to indicate when the unwound measuring devices are off line relative to the sighting device.

Abstract: An aircraft traffic pattern computer employing a slotted frame having a window surrounded by a compass rose which is movable in relation to the frame about a pivot point, the slotted frame being adapted for holding a placard having a pair of surfaces upon which various aircraft movement patterns are shown about a reference point and a reference line such that alignment of the reference point with the center of the compass rose and alignment of the reference line with the compass rose proper provides at least one selected course heading for an aircraft.

Abstract: An accurately formed straight edge member serves as a track for a carriage movable along the length of an elongated component. Distance measuring devices supported by the carriage engage the adjacent surface of the component by which flatness, bow and twist of the component can be determined.

Abstract: A go/no go pipe deflection gauge to be pulled through a pipe to determine whether the pipe wall has been deflected from a substantially circular cross-section. The gauge includes a spindle having an axis of length and a pair of ends. A cable can be connected to both of said ends so that the cable can pull the gauge through a pipe, and pull it back out if it becomes stuck. A plurality of vanes extends radially from the spindle. The vanes are angularly spaced from one another and extend parallel to the spindle axis. Each of the vanes has an outer boundary which includes a central substantially straight segment parallel to the axis, and a pair of end segments extending from the respective ends of the central segment toward the axis.

Abstract: A differential checking head for checking tooth-to-tooth spacing of evenly spaced toothed gears or for checking lead variations of helical gears is disclosed. The checking head includes a pair of sensing fingers which have contact portions that touch gear profiles at predetermined test points. One of the sensing fingers is mounted on an arm which is pivoted in a fixed frame and which carries a moveable sensor actuator. The other sensing finger is mounted on a second arm which is also pivoted on the fixed frame and which carries a moveable sensing element which engages the actuator that is secured to the first arm. Both of the sensing arms are returned to their initial positions by return springs; and a second sensor, or limit switch, may be actuated by the actuator that controls the first sensor. The checking head provides a differential reading dependent upon the relative motion of the two sensing arms.

Abstract: A bending level tool has a body with longitudinal axis defining a handle at the rear and thereof and axially aligned first level vial at the forward end, with a perpendicularly aligned second level vial attached to the body at an intermediate shank. A pair of spaced tines forming an attachment fork extend normally to the plane established by the axes of the two vials, with one fork flush with the forward end of the first vial and the second tine attached to the shank at the forward face of the second vial, and a screw attached to one of the tines for clamping a pipe wall against the opposite tine. The length and width of various functional parts of the bending level are of predetermined small increment dimensions, preferably multiples of one-fourth inch, permitting ready measurement of pipe diameters and the like, and the angular relations between parts of the level permit square measurement.

Abstract: For improved treatment of textile material after scouring or dyeing by application of microwaves, a preparatory heating chamber replete with steam is arranged for passage of the textile material substantially in a sheet form, and, is accompanied with a downstream microwave irradiation chamber of a confined construction replete with steam in which microwaves are applied to the textile material in the form of a rotating roll. Ideal aftertreatment can be carried out uniformly throughout the textile material at high thermal efficiency without any leakage of microwaves and steam.

Abstract: A nozzle for use in web treatment apparatus includes a carrying surface extending substantially parallel to the web and guide members defining an annular slit in a central region of the carrying surface, the guide members being formed such that gaseous medium flows radially through the slit in contiguity with the carrying surface and in a direction substantially parallel to the web.

Abstract: The invention relates to a shoe sole made of flexible rubber material with a non-slip profile on the wearing side.

Abstract: Plow apparatus for work vehicles, particularly of the type which travel on rails, including at least one plow plate pivotally mounted on a respective end of the vehicle in a manner such that the plow plate can be pivoted through an angle of about 180.degree. between a front plowing position in the track of the vehicle and a slide plowing position on the side of the vehicle. The plow plate is pivotally mounted about a vertical axis which is laterally offset to one side of the center-line of the vehicle. In this manner, as the direction in which the vehicle is driven is changed, the plow plate can be pivoted from the front plowing position to the slide plowing position and vice versa. Preferably, such a plow plate is mounted on each end of the vehicle, each plow plate being pivotable about a vertical axis which is offset to the opposite sides of the vehicle center-line.

Abstract: A scraper or dozer blade mounting for earth and snow moving equipment of the type having a pair of forwardly projecting parallel boom arms and a pair of hydraulic cylinders to control positioning of a bucket or blade carried by the boom arm. The mounting consists of a cross-member adapted to be secured to the forward ends of the boom arms, and a scraper blade centrally pivoted to the cross-member. Articulated link arms extend from each hydraulic cylinder and are pivotally secured to the blade on opposite sides of the central pivot, and means for actuating the hydraulic cylinders in reverse orders thereby enabling control of the inclination of the blade with respect to the path of travel of the machine. Such a mounting assembly enables known earth and snow moving equipment to be converted to highly maneuverable earth and snow plowing equipment.

Abstract: An apparatus for pressing cloth with a heated iron has a surface for supporting a cloth or other material to be pressed, one or more fans for moving air over the ironing surface by suction or by blowing and a switch for controlling electricity that drives the fan. The switch has a first capacitor which is disposed below and in front of the ironing surface. The switch is shaped to the outline of the ironing surface. A second capacitor having a semi-cylindrical cross-section is disposed between the first capacitor and the ironing surface.

Abstract: A method for processing table and bed linen which embodies no-iron fabrics which may be composed in at least a substantial part of polyester fiber, or may be composed of other fibers which have been treated to provide no-iron characteristics (linen being used in a generic sense rather than to identify the fiber composition). The process includes the sequential steps of laundering the linen, preferably in substantially conventional manner, and then folding the laundered linen in a dry state to provide a stack of multiple layers of the laundered textile fabric, all of the layers being of approximately equal area. The multiple layers of fabric are then finished by compressing the multiple layers in folded state in the presence of heat and moisture, causing steam to flow through the stack of multiple layers, first in one direction and then in the opposite direction.

Abstract: A wine list display container provides a horizontal barrel having a horizontal division cut therethrough providing bisymmetrical upper lid and lower base portions, each having coinciding mating face portions. At least one hinge is provided for connecting the upper and lower base portions together in a hinged fashion, the lid being movable on the hinges between closed and open positions. A pair of spaced feet are attached to the base for securely supporting the horizontal barrel on a flat surface, such as a table. An inner rack mounted within the barrel and on the barrel base supports a plurality of substantially equally sized information cards which can contain for example individual information on differing wines. A plurality of equally sized information cards are provided which removably and temporarily can be attached to the rack within the barrel with the cards and the rack being contained within the barrel when the lid assumes a closed position with the face portions mating.

Abstract: This invention is directed to a display device comprising light reflecting block means having at least one light path defined by wall members for reflecting the light emitted from a light emitting diode placed within said light path which is provided with an elongated opening for constituting a display segment and composite lens means having a plurality of juxtaposed lens columns and Fresnel part, said composite lens means are located on the light reflecting block means so that the display segment can be illuminated with uniform and intensive brightness upon electrically activation of the light emitting diode.

Abstract: A display device comprises a rotary carrier and a plurality of supports for respective display slats which supports are mounted on the carrier for rotation around the axis of rotation of the carrier and for rotation about respective axes, which are equiangularly spaced about the axis of rotation of the carrier. A slat is mounted on each support with its longitudinal center line coaxial with the axis of rotation of the support. The arrangement permits each slat to be turned to show both its faces and by movement of the slats around the axis of the carrier it permits alternative slats to be brought into the display surface.

Abstract: A trolling tackle device having a reversible power drive reel for raising and lowering a metal line and a heavy sinker in deep water trolling. A fishing line, bait and hooks are releasably attached adjacent the sinker and are thus to be lowered to the desired depth and are arranged to separate from the sinker line when a fish takes the bait. The drive is controlled by a switch so that when the sinker and tackle reach the desired depth, the switch is automatically opened and the reel is stopped with the tackle at a predetermined depth. When a fish is caught the fisherman throws the switch and the sinker line and sinker are pulled up by the power reel, preventing fouling of the lines by the action of the fish.When the sinker reaches the desired height the switch is automatically opened and the sinker held at a predetermined height.

Abstract: A fishing lure is provided which is snag-free and equipped with pivotted hooks retracted elastically within the body of the lure and movable outside the lure by action of a fish biting and pulling thereon. The lure comprises a body portion having a plurality (preferably four) hooks pivotally mounted therein and movable between a retracted position within and an extended position outside said body. The hooks are normally held in the retracted position by suitable elastic means, such as a rubber band, and moved to an extended position outside the body portion of the lure by longitudinally movable actuating means secured and guided in the body portion and actuated by a fish biting and pulling thereon. The fishing lure is particularly characterized by the fact that the hooks are always biased elastically toward the retracted position and at no point are spring-loaded outward and further in the particular features of construction that permit simultaneous actuation of four fishing hooks.

Abstract: Each block of a set of toy building blocks is in the shape of a cube with two in-formed recesses, one at one corner of the cube and the other in the diagonally opposed corner. The dimensions of both recesses are equal and cubic, and equivalent to half the length of one of the sides of the cube.

Abstract: A construction element, which may be used in constructing flexible universal joints for a variety of geometrical structures such as assembly toys and in combination with rods to particularly construct a cube-octahedron throwing toy, is disclosed wherein the element comprises a section of elastic tubing having diametrically opposed cutouts at its center to form a transverse opening adapted to receive a similar piece of tubing or other member. By inserting one of such elements through the cutouts in another of the elements until the cutouts register, they may be compressively held together and form a universally flexible, self-centering, cruciform joint which can be connected to four rod-like members and used in combination with like elements and members in assembling various polyhedral structures such as the preferred embodiment of a manipulatable throwing toy.

Abstract: A water toy or tube toy propelled by a jet of water includes an elongated body having an internal cylinder for containing a variable volume of water therein. A piston is mounted for slidable movement in the cylinder and is biased in one direction to decrease the volume of water in the cylinder by discharging a propelling jet stream of water from the rear end of the body. Valve means is provided permitting the filling of the cylinder with water when the piston is moved in an opposite direction and floatation means is provided for supporting the body on the water.

Abstract: An articulated toy figure or doll having a torso with limb members attached to it which are readily movable. A skeletal structure is provided for one or more of the limb members, which enables the limb member to be connected to the torso or another limb member, for movement relative thereto. The leg members of the toy figure are connected to the torso by a hip joint in such a manner that such leg members are swingably movable relative to each other, as well as relative to the torso.

Abstract: An electrical circuit module easily assembled by hand and especially adapted for use in a circuit package for a model includes an insulator substrate with an upper surface and a plurality of apertures extending through the substrate from the upper surface. A plurality of circuit components on the upper surface of the insulator substrate have leads extending into the apertures. A conductive eyelet extends into each aperture and is dimensioned to form a friction fit with the leads of the components and any additional connecting wires in each aperture. The circuit module may then be mounted in a base including a control panel for an electrical circuit including the module on the base. Light, sound and similar effects are generated by the circuit for a model mounted on the base.

Abstract: Electromagnetic radiation object position detection system and method are disclosed for detecting when an object is located in the path of a powered sliding gate. In a preferred embodiment, polarized microwave radiation is emitted from a source fixed relative to the sliding gate. This radiation is projected along and spaced ahead of the leading edge of the sliding gate by a redirecting means which moves with the gate. A second redirecting means also moves with the gate and redirects the radiation back to a detector fixed relative to the sliding gate which provides a signal when this radiation is detected. The presence of an object in the path of the sliding gate is indicated by the blockage of radiation in the beam moving with the leading edge of the sliding gate.

Abstract: An obstruction sensor for an electro-mechanically operated garage door which utilizes a bracket for supporting one end of the trolley that carries the door and which is driven by the motor either through a chain or worm and wherein an obstruction encountered by the door will cause the rail to move relative to a fixed bracket thus causing a reversing switch to be energized due to relative motion between the fixed bracket and the rail which will cause the motor driving circuit to reverse the motor thus causing the door to move away from the obstruction.