Abstract: Apparatus and method for automatically determining and indicating that the rotor of a steam turbine has attained a predetermined minimal temperature. Means are utilized for measuring axial dimensional changes of the steam turbine cylinder and rotor due to an increased temperature and summing pertinent axial dimensional changes thereby determining the axial expansion of the rotor which in turn, through known physical properties of the rotor material, corresponds to a temperature increase. This increase of the temperature added to the initial temperature of the rotor provides the total temperature, and upon the total temperature reaching a predetermined value, the steam turbine is available to be brought up to speed and loaded.

Abstract: Disclosed are apparatus and methods for controlling parameters of fluid-driven systems. A control unit of the invention compares an input control signal to a tachometer signal from a fluid-driven turbine to produce a flow signal for controlling the turbine speed. The speeds of turbines in series are linked by the tachometer signal of the first turbine acting as the control signal for the following turbines. A critical speed interval is identified in relation to a range of values of the control signal. As the speed of a turbine is increased or decreased, its control unit holds the turbine speed at the limit of the critical speed interval, then rapidly accelerates the turbine through the interval to avoid prolonged operation at the turbine's critical speed. The individual critical speeds of separate turbines in series may be accommodated by critical speed intervals defined in separate control units for each of the turbines.

Abstract: A demand defrost control system which responds to whether a predetermined evaporator temperature is reached during a defrosting operation. If the predetermined temperature is not reached, then a relatively shorter interval before the next defrosting operation is established. If the predetermined temperature is reached, then a relatively longer interval before the next defrosting operation is established.

Abstract: A water heater, converted from existing water heaters or in newly designed and manufactured water heaters, having a condenser tube of a refrigeration unit in thermal conductive contact but not intimate contact with the water to be heated, and having a sheath tube in conjunction with and outwardly disposed to the said condenser tube, and having the inter-space or inter-spaces between the said condenser tube and the said sheath tube filled with thermal conductive material, said inter-space being open or fragilely rupturable to the outside of the water heater.

Abstract: An apparatus for feeding yarn, or the like vice yarn guides which travel on an endless O-shaped floating-mounted track to present the yarn, or the like to the instrumentalities of a textile machine.

Abstract: Apparatus for feeding yarn, sliver or fibrous materials wound on stationary supply packages to a texile machine, comprising a plurality of movable material transporting elements and a plurality of movable material laying-in elements for feeding the materials from the supply packages to the textile machine, endless tracks defining working and return sections for said transporting elements and working and return regions for said laying-in elements, said transporting elements and said laying-in elements running in series on said endless tracks, and entwining of the materials during successive runs of said elements on said tracks is avoided by at least one deflection element by means of which the materials are fed via said transporting elements to said laying-in elements, during successive runs thereof through the working region, alternately from one and another side of a surface laid through the working region of said laying-in elements and the return section of said transporting elements.

Abstract: A washing machine comprising a housing, an outer tub disposed in the housing, an inner tub disposed within the outer tub, an agitator disposed centrally of the inner tub and fixed to a vertical drive shaft, the inner tub having perforations in wall portions thereof, a first drain line extending from a bottom portion of the outer tub, an annular chamber disposed proximate an upper portion of the outer tub and positioned between the outer tub and a wall portion of the housing, the chamber having holes therein placing the chamber in communication with upper regions of the outer tub, and a second drain line extending from the annular chamber and connected to the first drain line.

Abstract: A method of producing metal tubing, particularly thin-wall, large diameter metal tubing, by clamping one end of a tubular metal blank to a mandrel, rotating the mandrel and blank, and subjecting the blank to both axially and radial deforming pressures through a series of circumferentially spaced rollers to cause the metal of the blank to flow axially ahead of the rollers to reduce the wall thickness of the blank. To achieve the desired thin wall construction without rippling of the internal diameter, the ratio of linear feed of the tubular blank to rotational speed of the blank per inch of tube diameter is maintained in the range of 0.006 to 0.012.

Abstract: A ring rolling machine for rolling a ring blank engaged over a mandrel roll which has an outside diameter smaller than the inside diameter of the mandrel roll comprises a rotatable main roll having an annular curved surface. The main roll is rotated about a fixed axis which is spaced at a fixed distance from the mandrel. Its curved surface is divided into a loading zone having a radius less than the spacing from said main roll access to the ring blank, a rolling zone having a variable radius curved with a continuously increasing value and a rounding zone extending between the rolling zone and the loading zone which is of substantially constant radius.

Abstract: According to the claimed method a round wire is first flattened and then formed into a serpentine flat spring. The segment portions of this spring are bent up in the form of thrust shoulders and calibrated for height. The shaped spring is coiled into a spiral on a mandrel, compressed and heat-treated before cutting it into individual tangential expanders.

Abstract: A method and apparatus for forming a metal strip into a shape having a transverse concave, convex bow, for example, for forming slats for venetian blinds. The strip material is fed into the nip of a pair of forming rolls having complementary concave and convex peripheral surfaces, to provide the bow. In order to ensure that the resulting bowed strip is formed without any twist, the strip is fed along a substantially straight path upstream of the forming rolls, and the direction of this straight path is adjustable in a plane passing through the nip and parallel to the axes of the forming rolls.

Abstract: An internally cooled mandrel is provided with regularly arranged copper fingers projecting into the inner flow space and leaving a recess adjacent the outer surface which is filled with buildup. These fingers are arranged in axial rows in which the pins are staggeredly positioned.

Abstract: A rolling stand with hydraulic adjustment of the mill rolls comprises a hydraulic cylinder whose piston is acted upon by the adjustment spindle and whose cylinder body, in turn, bears upon the block in which the back-up or pressure roll is journaled. The sliding seal of the piston rides in a cylinder lining which is disposed in the cylinder and is sealed relative to the latter with stationary O-rings so that pressure equalization on both sides of the liner is possible, thereby preventing expansion of the line upon subjection of the cylinder to high pressures.

Abstract: An improved mounting for ironing dies used in forming drawn and ironed metal articles, such as can bodies, at high speeds is disclosed. The support is formed of a metal ring having a plurality of fingers extending outwardly and axially from the ring. These fingers act as springs to allow the ironing dies, which are deflectably mounted on these fingers, to shift slightly in a direction generally perpendicular to their axes to accommodate off-centered cups which pass through the ironing dies to be formed into can bodies. The improved support is unaffected by the lubricant present in great amounts in the die cavities and on the cups so that the ironing die support will not deteriorate over time.

Abstract: An apparatus and method for forming integral domed can bodies for aerosol cans. The apparatus is in the form of plural sets of tools, each set of tools including an inside tool and an outside tool so related as progressively to reduce the diameter of an end portion of the tubular body and in doing so gradually increasing the axial extent of an intermediate frustoconical portion. Each frustoconical intermediate portion is increased in extent axially by seating the previously formed portion on the inside tool and then shaping the blank on that same surface, whereby there is no interruption or stepping of the formed frustoconical intermediate portion of the blank.

Abstract: An apparatus is provided for shaping metal bars, particularly for forming eyes in spring leaves. The forming machine includes a table supported on a main frame and rotatable about an axis, a mandrel extending from the table about the axis, a positionable back stop member on the frame adapted to be operatively engaged with the work piece which is to be formed about the mandrel, a jaw assembly actuable to clamp the workpiece against the mandrel, and means to rotate the table to form the workpiece about the mandrel.

Abstract: The present invention relates to a standard surface assembly that may be used in conjunction with a pendulum type variable speed friction skid tester for calibrating the same. The standard surface assembly includes a standard surface specimen, such as aluminum oxide, and, in use, is positioned below a pendulum swing arm with a rubber tire secured about the lower remote end thereof. The standard surface assembly is positioned with respect to the pendulum such that the rubber tire passes generally tangential to the upper surface thereof, and because the rubber tire is locked it will skid across the upper surface of the standard surface. For any particular swing of the pendulum arm, the energy lost in friction by the skidding wheel against the standard surface is known and consequently the variable speed friction tester can be calibrated to reflect this energy loss.

Abstract: This invention relates to portable gas detectors having means for aspirating a sample of the atmosphere to be tested into the vicinity of two sensor devices, and including a water-trap comprising valve means arranged, in response to a drop in pressure in the flow line when water is accidentally sucked in with an aspirated sample, to temporarily close the sample flow path or to open a by-pass for detecting the presence of both natural gas and manufactured gas in the atmosphere.

Abstract: A device for indicating the fuel consumption rate of an internal combustion engine. The device includes a potentiometer having a sliding contact engaging a variable resistor portion to provide variable resistance between the contact and an output lead of the potentiometer. The sliding contact is mechanically connected to the engine throttle for adjusting the position of the contact such that the resistance between the contact and the output lead increases as the amount of fuel supplied to the engine increases. A meter for indicating the fuel consumption rate is included in an electrical circuit including, in series, a voltage source, the meter, and the potentiometer connected at the contact and the output lead. Circuit interrupting means are also provided to open the electrical circuit only when the throttle is in the idling position.

Abstract: In mass flow rate measuring apparatus wherein the fluid is ionized at intervals at a predetermined point of the fluid passage, a voltage is sensed when the ionized flow mass is collected by an electrode located downstream from the ionization point. Electromagnetic radiation, generated in response to the generation of a strong electric field that ionizes the fluid, is prevented by means of a gate circuit from being sensed as a signal for triggering a time measuring device. The signal from the gate circuit is coupled to a voltage sensing circuit that detects a point near or at the peak value of successive voltage waveforms to signal the time measuring device as a point of ion collection.

Abstract: An ultrasonic flowmeter for measuring the rate of flow of a fluid, comprising a conduit and two acoustic probes placed on a line inclined with respect to the axis of said conduit. The active end of the probes are bathing in an annular chamber formed by a sleeve extending the inner wall of the conduit in the measuring zone and a swell in the inner wall of the conduit, and in which the fluid may penetrate.

Abstract: A by-pass flowmeter of coaxial design comprises a transparent outer tube and a rotameter coaxially disposed within the outer tube and laterally spaced therefrom to define an annular by-pass chamber. An inlet is at least partially disposed within one end of the outer tube in fluid communication with both the rotameter inlet and an adjacent portion of the by-pass chamber while an outlet is at least partially disposed within the other end of the outer tube in fluid communication with both the rotameter outlet and an adjacent end portion of the by-pass chamber. As the by-pass flowmeter is of coaxial design, greater accuracy is obtainable than with by-pass flowmeters of non-coaxial design.

Abstract: There is disclosed a gas flow measuring and calculating system including a transducer for measuring line or flow pressure of the gas flowing through a conduit, a transducer for measuring the line or flow temperature of the aforementioned gas, a turbometer for measuring the gas flow through the conduit, and calculation means in the form of a microprocessor for repetitively calculating with high accuracy the base gas flow in terms of standard cubic feet, wherein the supercompressibility factor is computed based upon values of measured gas temperature and pressure for specific entered values of specific gravity and of the gas compaction, and there are a plurality of computing steps for each calculation of the base gas flow.

Abstract: Apparatus is provided for generating a signal proportional to the quantity of a substance in a container composed of electrically non-conducting material. The container is converted into an electrical condensor by mounting a pair of electrically isolated electrodes on the outside of the container in face-to-face relationship on opposite sections thereof, such that the substance to be measured is situated therebetween. The electrodes are connected to an electronic capacitance measuring unit, preferably including a charge pump frequency to voltage converter, which senses a capacitance of the electrodes and generates an output signal proportional to the sensed capacitance. In this manner, an instantaneous measurement of the quantity of the substance in the container can be obtained and recorded. The measuring unit can be calibrated such that its output is linearly proportional to the quantity of the substance to be measured.

Abstract: An improved fluid quantity indicator, such as for aviation fuel, of the type utilizing capacitive type sensing probes in which a capacitance change occurs proportional to the amount of fluid in a tank or container due to the dielectric constant of the fluid being different from that of air, in which the improvement comprises microprocessor control means for providing display and totalizing control in conjunction with automatic compensation for the zero fluid capacitance variation in a tank and automatic adjustment of the fluid full scale reading for variation in fluid tank capacitance.

Abstract: The specification describes a portable temperature sensing device adapted to maximize heat transfer from a selected location on a planar surface to the device while minimizing heat transfer from surrounding conditions. The device includes a frame made of thermal insulating material provided with a sealed cavity, a temperature measuring instrument in the sealed cavity, a heat transfer member having a high thermal conductivity and extending from the cavity to the exterior surface of the frame for intimate contact with the planar surface, and means for reading the temperature measuring instrument. The arrangement is such that the heat transfer member is essentially isolated from thermal effects of surrounding conditions when the device is in use.

Abstract: An apparatus for sampling liquid gas with minimum contamination includes a manifold assembly separated into three sections by two valves and having a vent at one end and a fitting for connecting a gaseous sample container to the apparatus at its other end. A liquid sample receiving cylinder is connected to the middle section of the manifold assembly. A flexible conduit, which may be connected to a unit to be sampled at one end, may be selectively coupled to the sample receiving cylinder or the first section of the manifold assembly for purging the service hose. The method of using this apparatus includes purging sections of the manifold, receiving cylinder and flexible conduit with residual gas vapor pressure in a sample container, purging the flexible conduit with liquid gas from a unit to be sampled, filling the receiving cylinder with liquid gas, and converting the liquid gas to a gaseous state in the sample container.

Abstract: Disclosed is a device for measuring the rotational speed of a diesel engine. The device comprises a sensor element of electrostrictive effect type adapted to be detachably mounted on a delivery pipe of a fuel injection system of the diesel engine and having an intrinsic resonance frequency between 100 KHz and 10 MHz. A high frequency electric signal is transmitted from the sensor element in response to a high frequency oscillation generated in the fuel within the delivery pipe when fuel is injected. The device further comprises an amplifier, a converter, a wave shaping circuit, an integral circuit and an indicator. The high frequency electric signal is processed in the device and the rotational speed of the diesel engine is indicated by the indicator.

Abstract: An ultrasonic test system for inspection of structural material includes a test electronics for controlling a plurality of ultrasonic transmitter and receiver channels. This test electronics is operated by sequencing the system through the several channels, but the evaluating circuit is common to the receive channels. The duration of the test, timing of launching, timing of beginning receiving response signals, time and duration of looking windows for identifying and timing particular responses, and comparison data, all are operating and acquisition parameters for operating the electronics. These parameters are furnished from external sources and are programmable and exchangeable, e.g., from test to test. At least some of these parameters are updated on the basis of data as acquired during the test.

Abstract: The system includes a plurality of individually selectable transmitter and receiver channels, a common controller and a common acquisition unit constructed to operate on the basis of parameters which are furnished to the controller and the unit as input signals. Some of the parameters are held in a memory and are withdrawn on the basis of test identification numbers to set up the acquisition unit. The acquisition unit has a transit time counter and two parallel operating looking window generators and several comparator stages, operating under utilization of such parameters. The data as acquired by a test, are accumulated and processed to determine new parameters, if necessary, and feeding them to the memory. The controller conducts the tests on the basis of sequencing the system through a group of test identification numbers, and provides also launch delay and receiving delays on the basis of externally, updatable parameters.

Abstract: A segment C' located in a medium constituted by a test-piece is scanned by means of a focused ultrasonic beam formed by a focusing transducer which is immersed in a couplant fluid such as water. In order to displace a focal point of the ultrasonic beam within the test-piece and to scan the segment C', the focus of the transducer is displaced in translational motion along a curve segment C which is the optical image of the segment C' in the interface between the test-piece and the couplant fluid.

Abstract: A semiconductor pressure transducer comprising a disc-shaped pressure-responsive diaphragm; a pair of radial strain gauge units having a piezoresistance effect, formed by injecting an impurity in the radial direction in the surface of the diaphragm; and a pair of tangential strain gauge units having a piezoresistance effect, formed by injecting an impurity in the tangential direction in the surface of the diaphragm, wherein the distance from the pair of the radial strain gauge units to the center of the circular diaphragm is greater than the distance from the pair of the tangential strain gauge units to the center of the circular diaphragm.

Abstract: This specification discloses an automobile starter motor having a lever pivotally coupled to the housing of the starter and movably supporting a pole piece so that energizing the starter causes the pole piece to move toward the housing and to align to seat against the housing. The connection between the lever and the pole piece is a ball joint connection which permits relative movement between the pole piece and the lever so that there is maximum engagement between the housing and the pole piece which increases the starter holding force by reducing flux path reluctance and equalizing flux distribution through the extremities of the pole piece, and simplifies manufacturing, by reducing solenoid power and thus coil windings required and by eliminating a rigid connection between the pole piece and lever.

Abstract: A single-axis coarse and fine adjustment device for driving a carriage comprises a pinion shaft rotatably supported by stationary support means and having a pinion meshing with a rack provided on the carriage, a connecting shaft rotatably supported with the pinion shaft and having a first and a second toothed portion, first decelerating gear means meshing with the first toothed portion to decelerate the rotation of the connecting shaft and transmit it to the pinion shaft, a fine adjustment shaft rotatably supported within the connecting shaft and having a toothed portion, a fine adjustment operating member for rotating the fine adjustment shaft, second decelerating gear means meshing with the second toothed portion of the connecting shaft and the toothed portion of the fine adjustment shaft to decelerate the rotation of the fine adjustment shaft and transmit it to the connecting shaft, a medium adjustment operating member rotatably supporting the second decelerating gear means and rotatably supported by the s

Abstract: The invention relates to a crank drive, particularly to a crank drive for photographic cameras having a crank including a crankpin, and a drawbar pivotable about the crankpin. The drawbar consists of first and second rods connected to one another, and disposed in respective substantially parallel planes, which rods are joined or connected by a hinge having a hinge axis substantially parallel to the crankpin axis.

Abstract: In an apparatus wherein an endless band is trained over a stationary guide roll and a stretching roll, and a nut-and-spindle mechanism at the ends of the stretching roll can displace the stretching roll in a plane defined by the axes of the rolls when the band is centered on the rolls, the band is automatically centered by two hydraulic double-acting cylinder-piston units. The first unit displaces either end of the stretching roll in the plane and the second unit simultaneously displaces one end in a plane perpendicular thereto. This displacement is effected in response to a control signal from a sensor adjacent each side edge of the band and tripped when the side edge moves into contact therewith as the band moves out of its centered position. The control signal operates a three-way solenoid valve in a hydraulic control circuit for the cylinder-piston units.

Abstract: A change-speed gearbox has coaxial input and output shafts. Five intermediate shafts are equi-spaced around the input shaft and each has two gears fixed thereto, one of which meshes with a common gear on the input shaft, the intermediate shafts being movable axially.Five gears of different diameters are fixed to the output shaft around which five secondary shafts are carried by a rotatable cage. The five secondary shafts each have two gears fixed thereto, one of which meshes with a different one of the gears on the output shaft.Any one of a possible twenty five gear ratios between the input and output shafts may be obtained by rotating the cage until a selected one of the secondary shafts is in the same radial plane as a selected one of the intermediate shafts, that intermediate shaft then being moved axially to bring the second gear thereon into mesh with the second gear on the selected secondary shaft.

Abstract: Six planets in a planetary gear are arranged in groups of two each wherein the planets of two groups are similarly spaced, the spacing of the two planets in the third group is larger but still smaller than the spacing from group to group. The radial lines of symmetry of the three groups are angularly spaced by 120.degree..

Abstract: A device for transforming a rotational motion into a linear motion comprising a shaft and a sleeve enclosing the shaft, the shaft and sleeve adapted for relative axial movement upon relative rotation of the shaft and sleeve. A plurality of rolling bodies between the shaft and the sleeve arranged in a closed track with a load carrying part in the form of a spiral line and a relieved recirculation part. The sleeve includes an inner portion of flexibly deformable material suited for contracting the rolling bodies and have a helical race track therefor and an outer portion provided with a recirculation channel for the rolling bodies. The shaft which is enclosed by the sleeve has a smooth surface and the rolling bodies are urged against the shaft by means of the inner elastic portion of the sleeve.

Abstract: A saw chain sharpening fixture is disclosed featuring an inverted U-shaped frame adapted to be installed on a cutter bar of a chain saw and having a sharpening opening in a frame. A pair of sharpening tool adaptor guides are mounted on sidewalls of the frame and diverge outwardly from the sharpening opening, the adaptor guides each having an elongated bearing surface the lowermost portion of which is adapted to be disposed below the top of the cutter bar for supporting a sharpening tool adaptor on a selected one of the guides.

Abstract: A lid lifter arranged for releasing and removing the lid from a self-sealing reclosable container, such as a NORPAK bucket, is comprised of an elongate arcuate bar which is configured for tightly fitting between the paired parallel flanges which encircle such buckets near their upper ends. An elastic fastener interconnects the ends of the bar and fits around the container to secure the bar thereto. An L-shaped fulcrum plate extending outwardly and upwardly from joinder to the bar has a medial opening arranged for loosely receiving a lever which has a rectangular pad attached to its inner end. The opening is located so that the pad fits under the rim of the bucket lid in a manner to lift a portion of it simultaneously outwardly and upwardly when the lever is pivoted in the opening, thereby releasing the lid from the container and lifting it so that it wil not become reclosed when the lifter is removed.

Abstract: The present invention relates to a method and apparatus for hacking brick specifically involving the stacking of uncured or green brick into a two course high brick stack prior to the bricks being transferred and stacked onto a kiln car for curing and drying. As a part of the method and apparatus of the present invention, slugs of brick material are received and successively pushed by a first pusher through a wire type brick cutter onto a receiving table, each slug resulting in a series of aligned bricks disposed in side-by-side relationship and referred to as a brick row. A vertically movable elevator assembly is mounted adjacent the supply table and includes at least two vertically spaced receiving levels formed therein with each receiving level being adapted to receive and support a row of bricks. As the elevator assembly is actuated up and down, individual brick rows are pushed into each of the respective receiving levels of the elevator assembly.

Abstract: The present invention relates to a method and apparatus for hacking and stacking brick. Brick slugs are received on an off bearing belt and transferred to a discharge area. At the discharge area, a pusher on a fore stroke engages a slug on the off bearing belt and pushes the same onto a receiving area. While the slug is being pushed on the fore stroke, another slug arrives at the discharge area, and the pusher on the aft stroke engages this slug and pushes the same off the other side of the off bearing belt onto an elevator assembly aligned with the off bearing belt which then moves up to a raised position aligned with a second receiving area. A second pusher driven in time relationship with the other pusher then moves the brick slug from the raised elevator assembly onto the second receiving area.

Abstract: An adjustable edge trimmer for removing the marginal excess of rubber from a longitudinally moving sheet of elastomeric material. The edge trimmer is biased into contact with the moving fabric and is free to follow the cord edge while maintaining the same cutting pressure in its movement. The cutting angle is independently adjustable irrespective of the transverse slant of the carriage that carries the edge trim cutter.

Abstract: The cutter is primarily intended for use in cutting holes of various sizes in self-adhesive pads used by people who have had Ilyostomy and collostomy operations. It consists of a holder in the form of a hinged case for a square pad, a rotatable blade carrier, and a blade adjustably carried in a radial slot in the blade carrier. The blade carrier is formed in two parts having a snap engagement with each other, and the arrangement is such that on release of the two parts from each other all of the components may be separated for cleaning.

Abstract: The invention disclosed pertains to improved raker (high) and low teeth for use in circular saw blades. Each raker tooth includes a leading face and a top portion. The leading face comprises a first and second planar surface wherein the second surface extends at a negative angle from the first surface and to the top that consists of five facets in which two pairs of facets lie in planes offset at a first and second angles from the plane of a first center facet. Each low tooth also includes a leading face and top portion. However, the leading face includes a first planar surface and a second portion consisting of five facets each of which extends from the first surface to the top portion at a negative angle of inclination, and two pairs of facets lie in planes offset at first and second angles from a first center facet.

Abstract: A programmable dynamic filter for use with a time-shared electronic organ or the like includes a filter circuit responsive to a logical state of a control signal for tracking notes generated by the instrument. Means are provided for programming the filter independently of generated notes by selectively adjusting the pulse width of the control signal to achieve desired musical effects.

Abstract: A tone generator system for an electronic organ which is capable of being fabricated into an LSI structure and receives a saw-tooth wave or staircase wave as an input thereto comprises a frequency divider for the saw-tooth wave or staircase wave including a ladder resistor network and a complementary MOS FET devices, an analog switch having a wide dynamic range and a high linearity in input-output transfer characteristic constructed by MOS FET devices to serve as an indirect keying means, a sustain means including a novel structure of a variable impedance element which is constructed to control a channel current in a MOS FET device by varying a potential distribution in a source region, and an impedance converter constructed by complementary MOS FET devices and free from a D.C. level shift. With the above arrangement a tone generator system of high quality for an electronic organ is provided.

Abstract: The invention relates to a drum shell for a musical drum, the drum shell comprising at least one portion molded or cast as one piece in natural or synthetic material, so enabling internal and external surfaces of the drum shell to be made in any desired shape.

Abstract: A roof bolt for use in a predrilled hole in a mine has an elongated stud on which is mounted a cylindrical sleeve. The first or inner end of the stud is threaded and carries a wedge adapted to enter one end of the sleeve and forcefully expand it in response to the rotation of the stud. The second or outer end of the stud is threaded in a like direction and carries a nut, held in a fixed position of rotation on the stud by a shear pin engaged in a common hole through part of the nut and stud. A shoulder plate is carried on the stud between the nut and sleeve, and the second end of the stud has a backing plate attached.