1,306 research outputs found
Phase-angle controller for Stirling engines
An actuator includes a restraint link adapted to be connected with a pivotal carrier arm for a force transfer gear interposed between the crankshaft for an expander portion of a Stirling engine and a crankshaft for the displacer portion of the engine. The restraint link is releasably trapped hydraulic fluid for selectively establishing a phase angle relationship between the crankshaft. A second embodiment incorporates a hydraulic coupler for use in varying the phase angle of gear-coupled crank fpr a Stirling engine whereby phase angle changes are obtainable
Hot gas engine with dual crankshafts
A hot gas engine, such as a Stirling engine is described which comprises a displacer portion and an expander portion with a heat exchanger connected between them. The expander portion has a piston which is operatively connected to and rotates an expander crankshaft. In like manner, the displacer portion is provided with a piston which is also operatively connected to and rotates with a separate displacer crankshafts. The two crankshafts are synchronized with respect to each other preferably by means of an idler gear. Banks of displacer pistons can also be provided for operation on a common displacer crankshaft and banks of cooperating expander pistons also can be provided for operation on a common expander crankshaft
Solar energy modulator
A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening
Squib-operated disconnect
Disconnect device is described, which consists of stud with enlarged end held in collet locked by pins, which are held in place by piston. When squib is fired, trapped combustion products force piston to release pins
Zero torque gear head wrench
A gear head wrench particularly suited for use in applying torque to bolts without transferring torsional stress to bolt-receiving structures is introduced. The wrench is characterized by a coupling including a socket, for connecting a bolt head with a torque multiplying gear train, provided within a housing having an annulus concentrically related to the socket and adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. As a result of the foregoing, the operator of the wrench is substantially isolated from any forces which may be imposed
Disconnect unit
A squib-actuated disconnect is characterized by an expandable collet axially extended from a first tension member for receiving in locking engagement a protuberance axially extended from a second tension member. A gas-driven retainer of an annular configuration is also locked in for supporting the collet in locking engagement with the protuberance. The protuberance is axially displaced in response to a firing of an associated squib for thus accommodating a disengagement of the protuberance and the collet
Bolt installation tool for tightening large nuts and bolts
Large bolts and nuts are accurately tightened to structures without damaging torque stresses. There are two models of bolt installation tool. One is rigidly mounted and one is hand held. Each model includes torque-multiplier unit
Liquid-fuel valve with precise throttling control
Prototype liquid-fuel valve performs on-off and throttling functions in vacuum without component cold-welding or excessive leakage. Valve design enables simple and rapid disassembly and parts replacement and operates with short working stroke, providing maximum throttling sensitivity commensurate with good control
Parents’ perceptions of the impact of early stage exam tests on anxiety levels in young children with and without Autism.
The study explores parental perceptions of the impacts of Key Stage One (KS1) Standard
Attainment Tests (SAT’s) on anxiety and the extent to which this may impact children with
autism. In the end, it will provide possible suggestions on how to reduce any negative impacts experienced by test anxiety. A mixed method research design was used, employing both questionnaires and interviews. Questionnaires were distributed to participants for structured interviews. The sample consisted of 32 parents with children aged between 6 and 7 years old attending primary schools across England. Participants were mothers (aged 28-34 years old) of which 28 were parents of children either with an official diagnosis of Autistic Spectrum Disorder (ASD) or currently awaiting an official diagnosis. The other four were parents of neuro-typical (NT) children. Data derived from parents of children with ASD were compared to data from parents of NT children. The data were gathered through both qualitative and quantitative measures. Overall, the findings suggest that parents of children with ASD reported an increase in the anxiety levels of their children during exam preparation, while parents of NT did not report any behavioural changes during this period due to anxiety. Findings suggest that exams at this early stage may have a detrimental effect on the well-being of children with ASD; therefore, implications for educational policy changes are made
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