Abstract: An apparatus to determine the swollen cross-link density of a polymeric specimen. The apparatus includes a support structure, a fluid-holding structure to hold a solvent, a first gripping assembly engaged with a weight scale and adapted to grip a specimen and a second gripping assembly adapted to grip the specimen. The fluid-holding structure is attached to a multi-stage device attached to the support structure and displaceable upward or downward. A mechanism supported by the support structure and engaged with the multi-stage device and configured to displace the multi-stage device in fine gradations. When a specimen is gripped by the gripping assemblies and submerged in the solvent and the mechanism displaces the multi-stage device downward, a tensile force is exerted on the specimen. The tensile force is measured by a displacement gauge.

Abstract: A load testing system comprising a load frame device adapted to load test one or more test specimens and to generate load test measurements; one or more environment controlling chambers adapted to be positioned within the load testing frame for subjecting the one or more test specimens to desired environmental conditions; one or more environment condition regulators adapted to be connected to the one or more environment controlling chambers for regulating the desired environmental conditions; a data acquisition device for receiving sustain load measurements of the one or more test specimens and environmental condition measurements to which the one or more test specimens are subjected during the load test; and a load monitoring device adapted to be connected to the data acquisition device for receiving and monitoring the sustain load measurements and the corresponding environmental condition measurements as a function of time.

Abstract: An apparatus and methods for measuring the clamping force applied to a substrate by clamping elements of a substrate holder. The apparatus include a pneumatic cylinder, a two position, three way valve and a pressure gauge. In a first position of the valve, the gauge and a bore of the cylinder are vented or pre-pressurized. In a second position of the valve, the bore and gauge are isolated. The methods include placing the apparatus with the valve in the first position between clamping elements set to a non-clamping position, moving the valve to the second position, setting the clamping elements to a clamping position and reading a pressure on the gauge.

Abstract: The invention relates to a test system for dynamically and/or cyclically load testing a material sample, a component, or an assembly, hereinafter referred to as sample. The test system is provided with a test frame, to which a bearing and a counter bearing are attached. At least one actuator comprising a multifunctional solid state transducer material system is connected to the counter bearing, directly or indirectly, to which, also directly or indirectly, a fastener provides firm fixation of the sample. Likewise, on the bearing side, a fastener firm fixation of the sample such that the at least one actuator is able to introduce dynamic and/or cyclical mechanical loads into the sample, which act along a load path extending lengthwise between the bearing and the counter bearing and through the sample.

Abstract: Automated fixture layout is approached in two distinct stages. First, the spatial locations of clamping points on the work piece are determined to ensure immobility of the fixtured part under any infinitesimal perturbation. Second, spatial locations are matched against a user-specified library of reconfigurable clamps to synthesize a valid fixture layout or configuration that includes clamps that are accessible and collision free. The spatial locations matching during the second stage can be the same spatial locations chosen in the first stage to ensure immobility, or a different set of spatial locations.

Abstract: A recursive hexapod testing machine for mechanical testing of deformable material specimens under six degrees of freedom multiaxial loading. The machine includes a fixed base, a movable base connected to the fixed base at by a hexapod arrangement of six linearly extendable actuator linkages, with an end of each linkages attached to the movable base and the other end of the linkage attached to the fixed base. Each actuator linkage includes a hydraulic cylinder and piston, a digitally-controlled electro-hydraulic servo-valve for actuating the hydraulic cylinder in response to a digital command string, a load cell in line between the piston and the universal joint attached to the movable base, a linear variable displacement transducer for measuring extension of the piston, and a magneto-resistive position transducer for measuring a position of the piston. The servo-valves extend each hydraulic cylinder a predetermined amount to effect a desired motion of the material specimen.

Abstract: The test fixture includes a housing, a first grip, and a second grip. The first grip and the second grip are each configured to clamp onto an upper surface and lower surface of a material coupon. The test fixture also includes an upper input jaw and a lower input jaw each configured to clamp onto the material coupon near a center of the upper surface and the lower surface of the material coupon. The test fixture is configured to load the material coupon in a first direction and a second direction. The first grip and the second grip are each configured to clamp onto the material coupon at a location which accordingly results in a desired testing ratio regardless of a variation in thickness of the material coupon.

Abstract: A test-specimen holder for gripping test specimens to perform material tests in the form of compressive and tensile tests has two grabs coaxially aligned relative to each other and capable of gripping the test specimen. The grabs have angled faces on sides facing away from the test specimen gripped between them. Respective hydraulic gripping cylinders are connected to the grabs for shifting same axially and a wedge can engage the angled faces of both grabs. A fluid-operated synchronization cylinder is connected to the wedge for moving the wedge perpendicular to the axis of the grabs into and out of engagement with the angled faces of the grabs. A fluid reservoir is connected through a 4/2 directional control valve with the gripping cylinders for actuating same. An adjustable first pressure-limiting valve and a check valve connected parallel thereto are connected between the 4/2 valve and the synchronization cylinder.

Abstract: A detecting device for performing fatigue tests on a pivoting piece includes a clamping module and an actuating module. The clamping module clamps the pivoting piece. The actuating module includes an elastic actuating shaft abutting the clamping module and a resilient member mounted in the elastic actuating shaft. The resilient member is adapted to push forward against spring pressure and retract by the release of spring tension so as to achieve cyclic movements in the pivoting piece.

Abstract: A testing apparatus includes a support mechanism, a pushing device, and a clamping device secured to the driving member. The clamping device secures a product. The pushing device includes a guiding pipe, a driving member moveably attached to the guiding pipe, and an elastic member received in the guiding pipe. The elastic member is connected to a first end of the driving member. The first end of the driving member is received in the guiding pipe. The clamping device is secured to the driving member. Wherein the guiding pipe is adapted to receive air, the driving member is adapted to be driven by air to move along a first direction, and the elastic member is adapted to rebound to pull the driving member to move along a second direction opposite to the first direction.

Abstract: A testing apparatus includes a support mechanism, a pushing device and a clamping device. The pushing device includes a guiding member, a driving member moveably attached to the guiding member, and a resilient component located between the guiding member and the guiding member. The clamping device is attached to the driving member, and secures a product. The driving member and the clamping device deforms the resilient component in a first direction, and the resilient component biases the driving member and the clamping device in a second direction, that is opposite to the first direction.

Abstract: A recursive hexapod testing machine for mechanical testing of deformable material specimens under six degrees of freedom multiaxial loading. The machine includes a fixed base, a movable base connected to the fixed base at by a hexapod arrangement of six linearly extendable actuator linkages, with an end of each linkages attached to the movable base and the other end of the linkage attached to the fixed base. Each actuator linkage includes a hydraulic cylinder and piston, a digitally-controlled electro-hydraulic servo-valve for actuating the hydraulic cylinder in response to a digital command string, a load cell in line between the piston and the universal joint attached to the movable base, a linear variable displacement transducer for measuring extension of the piston, and a magneto-resistive position transducer for measuring a position of the piston. The servo-valves extend each hydraulic cylinder a predetermined amount to effect a desired motion of the material specimen.

Abstract: The specimen holder serves for clamping workpieces, in particular for carrying out tests on components and materials in the form of compressive and, particularly, tensile tests. It is provided with two clamping jaws (5, 6), which can be made to move, preferably by hydraulic clamping cylinders (3, 4), are aligned coaxially in relation to each other and clamp the workpiece (2) between them. The two clamping jaws (5, 6) are provided on their side facing away from the work-piece (2) with wedge faces (7, 8), which lie against a wedge piece (9), which can be made to move by means of a likewise fluid-operated synchronization cylinder (10) perpendicularly in relation to the axis of the clamping jaws (5, 6) and in the direction of the test axis (11) of the workpiece (2).

Abstract: A test specimen holder includes at least one pair of wedges, a plurality of pistons and a tie bar connected to each of the pistons. A single cylinder body is operable with each of the pistons and the wedges. The cylinder body is adapted to urge the wedges together with relative movement of the cylinder body with respect to the pistons.

Abstract: An orthopedic simulator, such as a spinal implant wear test machine, is provided with a specimen containment module that may be removed from the machine as a unit. The releasable attachability of the specimen containment module permits remote specimen installation and reduces environmental contamination.

Abstract: A testing apparatus and method for simulating wind loads and evaluating wind resistance of a building component test specimen such as a sheet-metal roofing component. One or more arrays of pneumatic cylinders apply forces according to a specified test protocol to detach the building component from a test base. A software implemented computer control system may be provided to control the cylinders and apply the forces according to the test protocol.

Abstract: A hydraulic threaded bolt clamping device for tightening and releasing threaded bolts has a pressure medium supply connected to a pressure medium connector. A cylinder rests against a machine part that is to be clamped and a periodically pressure-loaded piston is guided seal-tightly in the cylinder and rests against a threaded bushing screwed onto the threaded bolt. A control device actuates the pressure medium supply for supplying pressure medium to the bolt clamping device. After a nominal value corresponding to a nominal prestressing force has been reached the pressure medium supply is switched off. The nominal screw prestressing force or a corresponding nominal pressure of the pressure medium supply is preset by an input device. A measuring device measures relative displacement of the threaded end of the bolt relative to the cylinder. An evaluation device determines residual actual screw prestress after pressure relief of the bolt clamping device.

Abstract: A test machine for testing the tension or compression properties of a test specimen is provided. The test machine utilizes magnetic force to prevent the fixture of the machine from rotating while placing the test specimen in tension or under compression, which accordingly prevents the test specimen from rotating as well as the source of such rotation. Unintended forces are thereby minimized, enabling a user to obtain more accurate test results.

Abstract: A testing apparatus and method for simulating wind loads and evaluating wind resistance of a building component test specimen such as a sheet-metal roofing component. One or more arrays of pneumatic cylinders apply forces according to a specified test protocol to detach the building component from a test base. A software implemented computer control system may be provided to control the cylinders and apply the forces according to the test protocol.

Abstract: A tortilla press utilizing a single sensor provides improved efficiency and accuracy. The press has a belt driven by a motor and a platen driven by a hydraulic cylinder. The motor is controlled by an AC inverter. A programmable logic controller (PLC) controls the AC inverter and hydraulics associated with the hydraulic cylinder of the platen. The PLC coordinates the movement of the belt and the movement of the platen. A sensor detects detectible elements on the belt and sends a signal to the inverter to initiate stopping of the belt. The inverter detects the zero hertz from the motor once the motor and belt have stopped and sends a signal to the PLC indicating that the belt has stopped. The PLC in turn passes a command that sends a signal to bring the platen down.

Abstract: A test specimen holder for holding a test specimen in a material testing machine includes a base member having a piston chamber, a valve chamber fluidly coupled to the piston chamber, a port fluidly coupled to the valve chamber and an end couplable to a material testing machine. A piston is movable relative to the piston chamber. A pair of first and second jaw assemblies are supported by the base members so as to be opposite each other. The jaw assemblies are operably coupled to the piston. A valve is disposed in the valve chamber and a valve stem is coupled to the valve. The valve stem is supported by the base member and is twistable to operate the valve. A user operable knob is coupled to the valve stem.

Abstract: A test specimen holder for holding a test specimen in a material testing machine includes a base member having a piston chamber, a valve chamber fluidly coupled to the piston chamber, a port fluidly coupled to the valve chamber and an end couplable to a material testing machine. A piston is movable relative to the piston chamber. A pair of first and second jaw assemblies are supported by the base members so as to be opposite each other. The jaw assemblies are operably coupled to the piston. A valve is disposed in the valve chamber and a valve stem is coupled to the valve. The valve stem is supported by the base member and is twistable to operate the valve. A user operable knob is coupled to the valve stem.

Abstract: An apparatus for applying a frictionless normal or radial force to a captured member. The apparatus has a fixed fluid bearing and a preloading, axially movable fluid bearing spaced apart from the fixed fluid bearing. A captured member is positioned between the fixed fluid bearing and the movable fluid bearing. A biasing member, disposed adjacent the movable fluid bearing member, biases the movable fluid bearing member against the captured member. The fixed and movable bearings each have oppositely adjacent end surfaces that define a recess for capturing the member therein.

Abstract: The present invention relates to a two dimensional stress relaxation testing device in which a plus shaped sample is stretched in mutually perpendicular directions simultaneously to monitor the stress and also the relaxation process of any sheet material in both axes. In view of this advantage, the present device provides the closest approximation to the in situ failure of the material.

Abstract: A testing apparatus for determining dynamic strength of sample paper cores includes a rotatably driven pneumatic chuck for engaging the inner surface of a sample core to rotatably drive the sample core, and a variable-tension belt assembly having a flexible belt which is looped over the sample core and tensioned to simulate the load applied to a paper core in actual use. The belt is tensioned by a pneumatic cylinder which is controlled under feedback control by a servo valve and a computer controller so that the load applied to the sample core accurately tracks a predetermined desired load schedule versus time.

Abstract: A multi-functional test machine is provided.

Abstract: A test specimen holder for holding a test specimen in a material testing machine that applies force loads to the test specimen includes a base member having a first end coupleable to the material testing machine and a second end remote from the first end. A longitudinal axis extends from the first end to the second end. A body member extends from the second end to the first end and includes an aperture disposed on the longitudinal axis for receiving the test specimen. A displacement device displaces the body member relative to the base member substantially parallel to the longitudinal axis.

Abstract: A method and apparatus for applying a force, displacement, or both to specimens, components, or systems by using a remote variable load/deflection device. The method enables testing of materials under actual in-service conditions. A displaceable container with a heating or heating and cooling element inside is provided. As heat is applied to the element, it expands thermally and causes the container to displace and apply force to specimens, components, or systems. The load/displacement of the container is modified by heating or cooling the element material. The container may be attached to in-service specimens, components, or systems and used to study the material behavior during in-service operation.

Abstract: A hydraulic grip suitable for use in both tensile and compressive loading of a specimen comprises generally a main body and an outer housing to form a pair of annular chamber thereinbetween. Hydraulic fluid under pressure alternately introduced into the chambers forces the outer housing to move up or downward relative to longitudinal axis of the main body. A cooling circulation may be established between the grip and a compressor so that the testing can be performed in high temperature. This grip also facilitates a rapid replacement of different grip jaws.

Abstract: A first kit includes a manually operable hydraulic pump, a hose and a fitting for transferring the pressure in the pump to the hose. A second tool kit for bearings of relatively small size includes a fitting for coupling to the hose in the first kit and a C-shaped clamp having a pair of legs movable toward each other in accordance with increases in pump pressure. A third kit includes a receiver die and a driver die movable with the clamp legs to remove a bearing from a housing, an anvil die and a driver die for installing a bearing in a housing and a die set for swaging a prepared lip in a bearing race into a prepared chamfer in a housing. A fourth tool kit for bearings of relatively large size includes a fitting for coupling to the hose in the first kit and an in-line press having a pair of legs movable toward each other in accordance with increases in pump pressure.

Abstract: A clamping or chucking tool for clamping a test sample in a testing machine has a clamping housing for applying a wedging action to the sample with the aid of one or two clamping jaws that are activated by an operating member that is inserted into the clamping housing and axially displaceable in the clamping housing. The clamping jaws are slidingly guided in a V-groove of the operating member but are stationary in the axial direction of the clamping housing, while the operating member is movable axially relative to the clamping housing for imparting to the clamping jaws a radial movement component perpendicularly to the longitudinal axis of the test sample. Lateral guide arms engage respective guide grooves in the clamping jaws to hold the clamping jaws against axial movement while permitting the radial movement. The clamping housing and the operating member are provided with at least one lateral opening for a rapid insertion of the test sample laterally into the clamping housing.

Abstract: A specimen grip for a test specimen that has an actuator for operating the grip remotely mounted and coupled to the grip through a tubular housing which provides for temperature isolation between the grip and the actuator. The grip is specifically adapted to be used in environmental chambers where the grip must operate in either high or low temperatures which can have an effect on the hydraulic actuator used in the grip and connected devices, such as load sensors. By maintaining the actuator on the exterior of the environmental chamber by having a pair of modules that are connected by a sectional connector, a grip can be installed through small ports in the environmental chamber. Once installed, the assembly permits viable operation because the actuator is temperature isolated from the chamber.

Abstract: A clamping device for applying loads to a test specimen including spherical egments connected to ends of the specimen. The spherical segments are in turn gripped by a race which allows pivotal movement of the segment. When the system is activated the race is gripped by the collet which is radially deformed by a circumferential clamp. When the spherical segment is clamped securely by the clamping device, the specimen may be axially or torsionally loaded by a reverse-direct stress testing device to determine physical properties of the specimen.

Abstract: A gage for quickly testing complex articles for conformance to a standard comprises a fixture configured according to the standard for holding the article and clamping the article into engagement with bearing surfaces. The bearing surfaces are instrumented with force sensors so that articles that deviate from the standard will produce force signals deviating from standard signals. A programmable controller quickly evaluates the signals to accept or reject the article.

Abstract: A grip for a material testing load frame including a grip plate for engaging the end of an elongated sample having a longitudinal axis and a grip body having one end for connecting to the grip plate and another end for connecting to a loading component of the frame, a mechanism for adjusting the concentricity of the plate with respect to the body, and a mechanism for adjusting the angle of the plate with respect to the body, so that when the sample end is engaged by the plate, and the grip body is connected to the loading component, the longitudinal axis and the axis of the loading component can be aligned with respect to the concentricity and angle.

Abstract: Hydraulically actuated grips are constructed to permit loading of specimens from either side of the grips. The grips are particularly adapted for use with flat specimens, are easily actuated, and are symmetrically designed so that when actuated, the grips do not exert any substantial axial load on the specimen and a uniform clamping force is applied laterally across the specimen. In addition, the grips, which can be used for either tensile or compressive loading, do not exert any bending moment on the specimen during test loading.