Abstract: A window insert assembly is disclosed having a spring-biased frame construction used to secure the insert within existing window frames of varying size. The insert assembly is particularly useful for mounting interiorly of an existing window pane to form a "double pane" insulative window structure, i.e., by creating a thermal cavity between the interior side of the existing window pane and the window pane of the insert. The insert assembly comprises a solid pane, such as a glass pane, mounted in a first frame. The first frame is received within a second frame which has movable sides for changing the size of the second frame. Springs are provided between the second frame and the first frame, preferably on all four sides of the rectangular window insert assembly, which bias the second frame outwardly relative to the first frame. The size of the second frame is adjustable by pressing one or more sides against this bias to fit the insert within an existing window frame in which it is to be installed.

Abstract: A pressure vessel and a method for distributing the stresses in a thick-walled high-pressure vessel, so that they lie within allowable limits, by constructing the wall in a series of generally concentric layers, at least one intermediate layer of which is to be constructed before the other layers. The intermediate layer is constructed above a base, resting on it through a sliding joint. Then it is placed under an external prestressing pressure. Thereafter, that layer is secured to the base by a rigid concrete connection. The remaining layers of the wall are then constructed and are subjected to an external prestressing pressure. Preferably, stress-relieving slots are applied to the innermost layer, during its construction.

Abstract: There is disclosed a reinforced, insulated concrete laminated wall. The central portion is a rigid insulation core through which vertical ladder structures extend transversely. Matched pairs of horizontal braces extend parallel to and abut the insulation core to hold it firmly in place. The horizontal braces rest on the rungs of the transverse vertical ladders and may be locked down to the rungs to prevent movement during concrete pouring. The wall is manufactured by positioning the core, ladders and braces medially between suitable forms. A single stage pour of concrete is then made to form the complete wall without resetting the forms. The wall may be constructed directly on a building foundation or prefabricated and subsequently positioned on the foundation.

Abstract: A raised panel door having a core panel extending within it and panel inserts lodged within the voids of a lattice structure presented on opposite sides of the door. Molding strips overlay and conceal regions where the inserts abut against expanses in the lattice structure defining the voids. A veneer overlay covers margins of the molding strips.

Abstract: A grill structure for use in connection with a combination screen and storm door, the grill being formed of vertical and horizontal channel members, the horizontal members comprising segments spacing the vertical members, rods extending through the channels of the horizontal members, the channels each having a rib therein and the rods each having a slot therein to receive a rod whereby the rods are non-rotatably disposed through the channels of said horizontal members to secure the framework of the grill, U-channel members from the perimeter of the grill and screws applied through said U-channel members into the ends of said rods secure the structure. The rods are held free from rotation and torsion therealong in securing the screws and the rods need not be held by hand against rotation as the screws are applied.

Abstract: A suspended grid subceiling and panel units therefor having the appearance of a continuous expanse of decorative light-transmitting block masonry. In a preferred embodiment, the panels units are assemblies of an opaque subgrid of rails and cross rails and translucent subpanels simulating the mortar lines and faces of glass block. The undersides of the grid main runners and cross runners are similar in shape to the subgrid rails and cross rails and have a surface finish matching the color and texture of the subgrid undersides.

Abstract: A method and kit for repairing in situ a utility pole, especially a wooden one, when damaged at around ground level uses a sleeve to surround a substantial length of the pole and a non-shrink hardenable pourable composition to occupy a clearance between the sleeve and the pole and form a solid core bonded to both of them, so as to yield a very strong assembly. Preferably the sleeve is of two identical parts clipped together round the pole, and the composition is a magnesium phosphate cement.

Abstract: Prefabricated architectural or decorative wall system having thin slabs of decorative materials, such as marble, granite, other natural stone or aggregates thereof, or other decorative exterior finish material, as an exterior finish bonded to the exterior of a thermally insulated structural panel. Such wall panels, including door and window openings are prefabricated at a plant location and assembled at the building site by use of internal fastening means. Each section or panel is itself a structural member and the system requires no frame or "superstructure" for support.The decorative exterior slabs are placed in rows or designs as aesthetics may dictate with adjoining edges spaced apart and those spaces filled with chemically modified concrete, grout or caulking to match material to be placed between adjoining panels on assembly.

Abstract: A support for a spanner bar in an open web bar joist system which is supported by a lower chord of the bar joist. The support includes a base member for securing the support to the lower chord, a first elongated vertical member which is affixed to the base member, and a second elongated member which is axially aligned with respect to the first member. Structure is provided for moving the second member axially with respect to the first member.

Abstract: A packaging machine for bonding a sheet to opposite walls and over the articles therein. One embodiment has a conveyor which moves the trays down a predetermined path, during which a film sheet is disposed over the tops of the articles in each of the trays, and flight bars traveling about an orbital path interpose the sheet between the trailing and leading walls of each of the successive trays and press the sheet against the adjacent trailing and leading walls. Heating elements associated with each of the flight bars heat the sheet, while compressed, to form a bond between the film sheet and the tray walls. The heating elements are controlled by an improved electrical circuit. Three independently movable sets of flight bars are provided for placing each of the trays in compression whereby the apparatus is adjustable as required to accommodate trays of different sizes over a range within the limits of the machine.

Abstract: A machine for automatically opening oppositely disposed handles or bails which are collapsed into and onto the bottom of continuously moving bakery baskets or trays. A pair of air cylinder-actuated, pivotally mounted, arcuate shaped lift arms partially lift the bails at a first station. A pair of fixed, sloped plow bars lift the moving bails a further partial amount at a second station. The opening of the bails is completed by a pair of air cylinder-actuated cam surfaced fixtures at a third station, readying the baskets for loading.

Abstract: Windrow shaping apparatus which is attachable to an existing rake for shaping forage windrows. The apparatus includes an attachment member for affixing the apparatus to a rake; a yoke pivotally engaging the attachment member; and a drum for engaging the forage in the windrow. The yoke and drum are supported at a desired height above ground level and at an inward angle so that the drum engages the top and side portions of the windrow to force the forage down and toward the center of the windrow. The drum includes a plurality of parallel spaced rods about the periphery of the drum to prevent excessive compacting and to prevent adherence of the forage to the drum. A second embodiment of the invention includes two drums carried by separate yokes, the drums both being inwardly inclined toward one another and obliquely placed, one in front of the other so as to overlap for simultaneous shaping of the forage on each side of the windrow without compaction between drums.

Abstract: A grass collecting bag for a lawn mower comprises a bag member opened at its one end and a cover member attached to the bag member so as to cover the open end of the bag member, the cover member being completely separable from the bag member.

Abstract: Disclosed is a crop finger extension for knife-finger guards of harvesting machines. The crop finger extension is detachably mountable on a crop finger body having an underside and an outer end. The crop finger extension includes a body portion having an upper surface with a forward end and a rearward end. A recess is provided in the body portion adjacent the rearward end of the upper surface to snugly receive the outer end of the crop body. A rearward extension extends rearwardly of the recess on the underside thereof and is adapted to locate against the underside of the finger body. The rearward extension is provided with first means engagable with corresponding second means on the finger body to lock the finger extension in position on the finger body. A crop finger is also disclosed.

Abstract: The collector apparatus of the instant invention is intended for use on a harvester vehicle for collecting a crop harvested from plants arranged in rows. The apparatus includes a pair of elongate continuous conveyor belts formed of pliable are resilient material, each conveyor belt having elongate inner and outer runs, the inner runs being disposed adjacent and opposite each other. The conveyor belts have faces delineated between the lateral margins of the belt that face upwardly. An elongate conveyor frame is associated with each belt for supporting the conveyor belt and includes training means for training the conveyor belts thereabout. Means ar provided for driving the conveyor belts in counter rotating paths. Attachment means are provided for attaching the conveyor frames to the vehicle.

Abstract: A baler for forming large round bales and drawn behind a tractor has an expandable bale forming chamber for receiving a crop windrow fed thereto by a pick-up device. Sensing means responsive to expansion of the chamber automatically steers the baler relative to the tractor in a sinusoidal path along the crop windrow to feed material over the length of the forming chamber. Turning movements of the baler are alternately in opposite directions transversely of the windrow at the same rate and like degree, and take place with an increasing frequency to a final expansion of the chamber to produce a cylindrical bale of uniform diameter.

Abstract: An archery string is produced of polyethylene monofilaments of a super high molecular weight by multi-staged bundling and twisting in order to lower the elongation percentage, thereby assuring high hitting rate in shooting and better endurance.

Abstract: The perforated roller of a friction spinning unit includes an outer sleeve having vent openings at one end to provide an air leakage path which by-passes the adjacent bearing of the sleeve, and further by-passing vent passages radially outwardly of the bearing at the opposite end of the sleeve.

Abstract: An open-end spinning device has a driven spinning chamber and an outlet tube mounted coaxially with the spinning chamber. A projection is provided on the inner curvilinear surface of the outlet tube, the projection extending along a spiral uncoiling in the direction towards the spinning chamber. The configuration of the projection spiral is chosen in such a manner that the projection of the angle formed between a tangent line to the spiral and a line drawn at right angles to the longitudinal axis of the outlet tube on an imaginary plane drawn at right angles to the longitudinal axis of the outlet tube in the zone of a portion of the spiral most distant from the spinning chamber is between 30.degree. and 40.degree. which corresponds to the angle of turns of the yarn produced in the spinning chamber.

Abstract: A control apparatus for the bleed valve of a gas turbine engine compressor enables the engine to be operated with a low risk of compressor surge or stall, particularly on emergency shut down.The control apparatus includes a control valve and a diverter valve. In normal operation the bleed valve is controlled by the control valve which receives a flow of high pressure air from the engine compressor. In an emergency shut down, the diverter valve is operated to allow the high pressure air to flow directly to the bleed valve, without passing through the control valve.The diverter valve can be fuel pressure responsive or solenoid operated.

Abstract: To prevent dust and other debris from entering the compressor (12) of a gas turbine engine (10) an inlet particle separator (30) is provided. Air contaminated with dust and debris is induced into a scavenge chamber (32). An exhaust vent (35) is provided from the scavenge chamber (32) through which the contaminated air is ejected to atmosphere. Flow dividers (40,42,44) are positioned in the scavenge chamber (32) to ensure that the flow into the chamber is uniform around the inlet passage.

Abstract: The internal combustion engine comprises a stator (1, 9) and a rotor (7) rotatably mounted on the stator (1, 9). The stator (1, 9) comprises at least one stationary combustion chamber (11) having an outflow opening (19) directed towards the rotor (7). On the rotor there is provided at least one working surface (25) movable past the outflow opening (19) charged by the outflowing combustion gases. Charging and ignition equipment charges the combustion chamber (11) intermittently with combustion gas and ignites the charge. The charging and ignition equipment includes a compressor which chages the compressed combustion gas substantially oppositely to the direction (43) of outflow of the iginited combustion gases from the combustion chamber (11).

Abstract: A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

Abstract: An ultrasonic fog generator can be used to advantage in injecting a fog into the input air of a combustion chamber, in order to improve efficiency and reduce the noxious emissions in the exhaust. In accordance with one form of the disclosure, a heat exchange is utilized to advantage in a turbine system in reheating compressed air that has been cooled as the air was fogged, the reheated air being input to the combustion chamber. In another form of the disclosure an adjustable heat exchange is used to controllably heat input air before the fogging thereof, the level of heat exchange depending on properties of the input air and the level of fogging to be implemented.

Abstract: A method and apparatus wherein a diesel having an exhaust-gas passage, a particle filter at a location along the exhaust-gas passage and a bypass passage bypassing the particle filter is started with the bypass passage closed, is operated at idle and up to a predetermined partial load with the bypass passage open and is operated beyond the partial load with the bypass passage closed so as to reduce particulate emissions and to assure regeneration of the particle filter.

Abstract: The invention contemplates a hydraulically operated twin-cable suspension for a clamshell or the like load-handling device. In a preferred embodiment, a charged accumulator is effectively a counterweight and is the source of all hydraulic fluid needed for the full range of actuation of two traction cylinders, one for each of the respective cables. Both cables automatically share the load, without slack, in any elevational situation, and simple hydraulic control circuitry selectively enables (a) an automated closing dig into loadable material and (b) a quick opening for load discharge. A single power integrator is interposed between the accumulator and the two traction cylinders for directionally controlling hydraulic-fluid displacement between the accumulator and the traction cylinders, as needed for all cable displacements.

Abstract: A master cylinder of the quick-fill type has an open-ended pressure cylinder closed by a closure member and a reservoir mounted on the cylinder. The closure member partially defines a quick-fill chamber in which slides a piston connected to a piston of the pressure cylinder. A valve controls communication between the quick-fill chamber and the reservoir.

Abstract: A fabricated master cylinder includes a pressure cylinder and a separately made reservoir mounted thereon by way of a mounting device on the cylinder and a mounting formation on the reservoir. The mounting device and reservoir provide restraint surfaces for engagement by a locking device which, when engaged, maintains the cylinder and reservoir in co-operative relationship. In an alternative arrangement, the restraint surfaces are on respective parts of the mounting device and formation which, themselves act as locking means.

Abstract: An intercooler for a supercharger in an internal combustion engine for a vehicle. The intercooler is an air cooled type provided with a pair of tanks which are connected by a core having a plurality of parallel heat exchanger pipes, between which cooling air is passed to cool the air in the pipes. Each heat exchanging pipe is vertically extended. The core has a horizontal elongation in the direction in which the pipes are arranged in juxtaposition which is larger than the vertical elongation in the direction in which each heat exchanger pipe is extended.

Abstract: A method and apparatus is disclosed for controlling the supercharging pressure in a turbocharger to obtain sufficient turbocharging even in low speed operating ranges. The supercharging pressure is regulated by a variable geometry means and an exhaust bypass valve means, which in turn are responsive to control means which receive feedback correction. The feedback correction is based on calculated controlled variables. Optimum control of the supercharging pressure is accomplished by finding a learning amount based on the feedback correction which in turn is used to modify the calculated control variables.

Abstract: The plant has a steam generator connected to a multi-part steam turbine which drives an electrical generator and has intermediate superheaters between the turbine parts. It is driven by steam supplied at supercritical pressure by the steam generator. A second electrical generator is driven by a multi-part gas turbine with multiple expansion and intermediate heating of the turbine gases. The heated turbine gases issuing from the gas turbine are fed to heating surfaces in the steam generator and to a preheater, connected to the latter, for the condensate flowing in the steam circuit back to the steam boiler. The turbine gas heaters integrated with the intermediate superheaters in the steam circuit are formed in a boiler fired with fossil fuels.

Abstract: A load sharing apparatus and method for coupled master and slave engines having respective throttle actuators to receive initial throttle signals, and load transmitters for transmitting load signals reflecting load on the particular engine. Apparatus has a load comparison structure which receives load signals from the load transmitters of the engines and produces a differential signal reflecting comparison of the engine loads. The apparatus also includes a servo structure which receives the differential signal and produces an output signal which is a servo signal. The servo signal is transferred to the throttle actuator of the slave engine, to change the initial throttle signal to the slave engine by an amount dependent on the servo signal thus sharing loads equally between the master and slave engines.

Abstract: An automatic transmission, for a vehicle with an engine, includes a hydraulic fluid pump which supplies pressurized hydraulic fluid. It is detected whether or not the engine is being started, and the pump output is controlled so as to be decreased when the engine is being started. If the pump is one whose output per one revolution of its input member is variable, then its output may be thus controlled by decreasing its output per one revolution when the engine is being started. And, if the pump is a variable capacity type vane type hydraulic fluid pump the output of which per one revolution of its input member is controlled by varying the eccentric position of a controlling member thereof, then its output per one revolution may be thus controlled by varying this eccentric position to give a pump output per one revolution decreased when the engine is being started.

Abstract: A process and apparatus for deriving useful heat from a low temperature waste heat-carrying fluid by means of a medium which can be divided into a strong solution in vapor form and a weak solution, the medium circulating in a closed circuit. Waste heat is used to divide the medium into the two solutions at low pressure, after which the strong solution is condensed, placed at increased pressure and then evaporated by receiving additional waste heat. The weak solution is placed at increased pressure and then mixed with the evaporated strong solution at increased pressure to absorb the latter and cause it to liberate heat. The resulting mixture is used to, successively, superheat the evaporated strong solution at increased pressure, heat the weak solution at increased pressure and heat the condensed strong solution at increased pressure, after which the pressure of the mixture is reduced to provide the medium which is divided into the two solutions.

Abstract: A refrigeration system is disclosed having greatly improved efficiency. The system includes a pre-cooler heat exchanger for sub-cooling the refrigerant hot gas from the compressor before entering the condenser to render the entire evaporator more effective for refrigeration purposes. The heat exchanger for pre-cooling the hot gas has one passage through which the hot gas flows and another passage, in heat exchange relation therewith, which is connected to receive a small flow of liquid refrigerant bled off from the main stream of the liquid refrigerant which refrigerant passes through an expansion valve or capillary tube to vaporize so that the refrigerant hot gas is sub-cooled by the latent heat of vaporization of the vaporizing refrigerant. This heat exchanger is located between the compressor and the condenser. The flow of the vaporized refrigerant used for cooling in the heat exchanger is connected to the return flow of vaporized refrigerant flowing from the evaporator to the compressor.

Abstract: An improved air conditioner for supplying temperature-controlled air to the interior of a room from a ceiling position where the air conditioner is installed without danger of condensate dripping from the air conditioner into the room. Air is sucked from an outer case intake vent into a heat exchanger and the cooled air is blown into the room with blowers. The heat exchanger and the blowers are installed in a suspended outer case in a space above the ceiling of the room. The air sucked from the intake vent is led to air supply vents provided on both sides of the undersurface of the outer case through the air supply trunk, the air supply trunk being divided into sections by a bulkhead.

Abstract: A compressor for a reversible refrigeration cycle is connected to indoor and outdoor heat exchangers through first and second refrigerant pipes. The compressor includes a closed casing defining an accumulation chamber therein. A compression section having a compression chamber is disposed in the casing so that a refrigerant is compressed in the compression chamber and then discharged into the accumulation chamber. A valve mechanism is disposed in the compression section and has a slider. The slider is arranged to be movable between a first position where the first and second refrigerant pipes are connected to the compression chamber and the accumulation chamber, respectively, and a second position where the first and second refrigerant pipes are connected to the accumulation chamber and the compression chamber, respectively. The slider is shifted to the first or second position by the pressure of the refrigerant.

Abstract: This invention relates to a device for returning oil to at least one compressor (1) in a cooling or refrigerating system, in which the compressor sucks oil (16) from an oil collecting container (13) through at least one suction conduit (14) connected to the collecting container (13) and having one or more gas and oil intakes (15) which is or are situated above the oil level (16a) in the collecting container (13).

Abstract: A magnetic refrigerator has a rotating magnetic wheel which includes a stack of spaced rings of magnetic material. Heat transfer plates of a high temperature heat extractor are interleaved with the magnetic rings and extend to a solid heat transfer conduit which leads to a high temperature terminal. Superconducting magnet coils are mounted to provide a magnetic field through the magnetic wheel at the position of the high temperature heat transfer plates. Low temperature extractor heat transfer plates are positioned outside of the magnetic field and interleave with the rings of the magnetic wheel to transfer heat thereto which is conducted from a low temperature terminal through a solid conduit.

Abstract: A tubular circularly-knitted cuff member including a plurality of integrally knit alternating coursewise rib portions and intermediate coursewise connecting portions, each rib portion having a set bulky terry yarn and stretchable low denier ground yarn knitted in plated terry stitch construction with an elastic yarn inlaid in alternate stitches to produce a radially-outward rounded terry loop surface and each connecting portion having the ground yarn in a single jersey stitch construction with the elastic yarn inlaid alternately therein. The cuff member is stretchable axially between a relaxed condition with the rib portions closely axially adjacent one another and the connecting portions generally not visible and an extended condition with the rib and connecting portions elongated to space the rib portions axially apart. A method of knitting the cuff member is also disclosed.

Abstract: Apparatus for wet processing traveling continuous-length textile material includes a narrow U-shaped container for processing liquid through which the material passes in a U-shaped path and an agitating assembly positioned in the container between the reaches of the material path for reciprocating movement parallel to the material. The agitating assembly includes a plurality of unequally spaced displacement members which extend across the width of the material and a substantial extent of the container transversely between the material reaches to define relatively narrow localized spacings between the displacement members and the container walls. Each reciprocal movement of the agitating assembly displaces a relatively large volume of the contained liquid forcing it to pass through the localized spacings at a relatively higher velocity than the actual movement of the agitating assembly, enhancing the liquid application to the material.

Abstract: A lockable clamp ring for securing an electric meter to a meter housing flange, which incorporates a unitary structure with moveable parts. The ends of the split ring are held within a Y-shaped housing and a similar shaped spreader which are manipulated to hold the ends of the ring closed in a locked position, and open when it is desired to remove the ring.

Abstract: A solenoid activated locking system primarily for hood and trunk manual release systems for vehicles. The solenoid is connected to a cable tied to the latch of a conventional hood or trunk release system. Unless activated, the solenoid prevents manual release of the trunk or hood lids to prevent access to the truck or engine compartment to someone who has obtained unauthorized access to the vehicle interior. The solenoid is automatically actuated for a preselected period of time whenever the ignition is turned on or off or when a reset switch is closed for more than a minimum and less than a maximum period of time. In addition, the solenoid is activated automatically during closure of the hood or trunk lid to permit secure engagement of the corresponding latch mechanism. An emergency release cable, hidden in an obscure location external of the vehicle, is provided for enabling manual release of the solenoid in the event of vehicle battery failure or other otherwise disabling event.

Abstract: An electro-mechanical locking device, including a dead bolt having a slot at one end portion and having at its other end portion a tip configured to enter a preformed shaped aperture while assuming at least one orientation and to be blocked by rim portions of said aperture while assuming at least one other orientation and an electrically operable means for applying a rotary movement to a guide member for the dead bolt. The guide member is coupled to the bolt by means of the slot. The device further includes a key operated unlocking and locking actuator means connected to said bolt for effecting linear retraction and extension movements of the bolt when acted upon by the key, while allowing rotary movement of the bolt by said guide member when the guide member is acted upon by the electrically operable means.

Abstract: Apparatus and process for providing the internal portion of tubing with a spiral groove or fin, or preferably a plurality of internal spiral fins, and which apparatus and process include a rotatably mounted spinner provided with one or more external ridges, which, upon relative movement of the tubing with respect to the spinner imparts rotation to the spinner causing the ridge or ridges to engage the tubing internal portion and provide at least one internal spiral groove therein; upon a plurality of external spiral ridges being provided on the spinner a plurality of internal spiral fins are formed.

Abstract: In order to form materials (18) in a cold state automatically and reproduceably a bending machine (10) is proposed, comprising at least two bending carriages (14, 16), which interact with the material so that one of the bending carriages (14 or 16) constantly holds the material (18) immoveable when the other bending carriage (16 or 14) is bending the material (12) or is being moved along it.

Abstract: Apparatus and method are provided for resiliently clamping a redraw cup (82) against a redraw die (34) in a crank and slide press (144) of the type having a redraw carriage assembly (12) that includes a redraw sleeve (62), and for slidably mounting the redraw carriage assembly (12) to the crank and slide press (144). The apparatus for resiliently clamping the redraw cup (82) against the redraw die (34) includes a fluid actuator (58) that is disposed circumferentially around the longitudinal axis (20) of the redraw die (34) and circumferentially around the redraw punch (46). The apparatus for slidably mounting the redraw carriage assembly to the crank and slide press includes guide rails (86a, 86b, 90a, and 90b) and pluralities of rollers (126a-126d).

Abstract: The rolls of a universal type mill stand are adjusted by moving the lower horizontal roll into position, directly or iteratively, by shifting the upper horizontal roll axially under utilization of the vertical rolls. In the case of conical rolls the latter operation is included in the iteration to obtain minimum spacing between the vertical rolls. The position of all rolls under rolling pressure serves as reference for further adjustment towards dimensions of the stock.

Abstract: An adjustable clevis includes a pair of opposed, spaced clevis members each having one end thereof secured to a cylindrical body. The body may consist of a threaded bore or a threaded stud to permit coupling with the male or female components of a linkage or the like. The clevis members are formed by passing a sheet of metal through a progressive die which shears and coins blanks into a configuration consisting of an outer perforated ear and an arcuate base having an inner curved surface which conformingly engages the body and is off-set relative to the ear.

Abstract: An apparatus for testing the calibration of hard disk substrate tester includes a calibrating micrometer moving a known surface to at least two distances from a non-contact detector in the hard disk surface tester and a known distance from each other, and further includes a piezoelectric transducer mounted to the known surface moved by the calibrating micrometer, and an oscillator oscillating the surface at predetermined frequencies and amplitudes.