Abstract: A novel engine for producing power from a temperature differential with additional benefits of low cost, high efficiency, quiet operation minimal wear of components, and the ability to produce power or cooling from low grade heat sources.

Abstract: An energy transfer machine, for example, a positive displacement internal combustion device, has a fixed or rotating outer housing, an internal rotating carrier and one or more inner rotors with rotational axes which are offset from the inner rotor carrier rotational axis. Circumferentially expandable projections from the outer housing and rotor mesh with each other to define variable volume chambers.

Abstract: A pump comprises a driving rotor and a driven rotor that are positioned in a housing such that, as the driving rotor and the driven rotor rotate, the teeth of the driving rotor and the teeth of the driven rotor mesh to form a positive displacement seal. The teeth of the driving rotor and the driven rotor are configured such that seals between the inlet side and the discharge side of the pump are formed between only the leading surfaces of the teeth of the driving rotor and the trailing surfaces of the teeth of the driven rotor.

Abstract: An energy transfer machine, for example, a positive displacement internal combustion device, has a fixed outer housing, an internal rotating carrier and one or more inner rotors with rotational axes which are offset from the inner rotor carrier rotational axis. Projections from the fixed outer housing and rotor mesh with each other to define variable volume chambers. In another energy transfer machine, in which the outer housing may be fixed or rotating, projections of the rotor are expandable within cylinders defined by projections of the outer housing.

Abstract: An energy transfer machine, for example, a positive displacement internal combustion device, has a fixed or rotating outer housing, an internal rotating carrier and one or more inner rotors with rotational axes which are offset from the inner rotor carrier rotational axis. Circumferentially expandable projections from the outer housing and rotor mesh with each other to define variable volume chambers.

Abstract: A spring shoe, and also in particular a spring, as well as a method of returning energy to a user, are provided. In one embodiment, a method and apparatus stores foot strike energy and releases it after a slight delay, when it will exert a force on the user which includes a forward component. This is accomplished in an embodiment by a spring in the sole which has a decreasing spring force, such that the force required to compress the sole decreases for all or part of the compression displacement as the spring is compressed.

Abstract: A pump comprises a driving rotor and a driven rotor that are positioned in a housing such that, as the driving rotor and the driven rotor rotate, the teeth of the driving rotor and the teeth of the driven rotor mesh to form a positive displacement seal. The teeth of the driving rotor and the driven rotor are configured such that seals between the inlet side and the discharge side of the pump are formed between only the leading surfaces of the teeth of the driving rotor and the trailing surfaces of the teeth of the driven rotor.

Abstract: An energy transfer machine, for example, a positive displacement internal combustion device, has a fixed outer housing, an internal rotating carrier and one or more inner rotors with rotational axes which are offset from the inner rotor carrier rotational axis. Projections from the fixed outer housing and rotor mesh with each other to define variable volume chambers. In another energy transfer machine, in which the outer housing may be fixed or rotating, projections of the rotor are expandable within cylinders defined by projections of the outer housing.

Abstract: A device to convert energy having exterior and interior rotors where the number of legs (?) of an interior rotor divided by the number of chambers (X) defined by the fins of the outer rotor is equal to the effective radius of the inner reference circle ri divided by the effective radius of the outer reference circle ro (i.e. ?/X=ri/ro). Where the surface of the fins of the outer rotor and the toe and heel portion of the interior rotor allow for a sealed chamber for a finite amount of rotation of the inner and outer rotors.

Abstract: A pump comprises a driving rotor and a driven rotor that are positioned in a housing such that, as the driving rotor and the driven rotor rotate, the teeth of the driving rotor and the teeth of the driven rotor mesh to form a positive displacement seal. The teeth of the driving rotor and the driven rotor are configured such that seals between the inlet side and the discharge side of the pump are formed between only the leading surfaces of the teeth of the driving rotor and the trailing surfaces of the teeth of the driven rotor.

Abstract: A flow meter comprising a rotor assembly that is comprised of two rotors having axis of rotation offset from collinear where the two rotors define operating chambers that changing volume with respects to rotation and allow fluid to pass from an inlet port to an outlet port when the number of rotation is indicated the volumetric flow therethrough.

Abstract: A positive displacement device that incorporates two rotors that are offset from collinear and each comprising a first and second set of vanes where the engagement surfaces of the first set of vanes are adapted to only engage when the rotors are in the top dead center location and the second set of lobes of each rotor only engage one another at the bottom dead center position of rotataion.

Abstract: A flow meter comprising a rotor assembly that is comprised of two rotors having axis of rotation offset from collinear where the two rotors define operating chambers that changing volume with respects to rotation and allow fluid to pass from an inlet port to an outlet port when the number of rotation is indicated the volumetric flow therethrough.

Abstract: The present invention provides a cohesive progression of various sizes and shapes and styles of tooth and gum cleaning devices which are ideally suited to each stage of a child's physical and psychological development, and which maintain elements of familiarity to the child from stage to stage to make the progression less dramatic and less stressful to the child and to the caregiver.

Abstract: An improved rotary engine and method for determining the contours of the sealing surfaces thereof. The improved engine provides for maintaining a predetermined, optimal gap between the sealing surfaces during rotation. The gap may be parallel or angled, and may be positive or negative so as to form an interference engagement. The rotors of the engine may be provided with mirror-image sealing surfaces so as to prevent development of excessive back-lash and clearance, and also to permit efficient reverse operation. The sealing surfaces may also be provided with recesses for interrupting the seal at predetermined points in the rotational cycle, for enhanced wear characteristics and/or to accommodate abrasive or shear-sensitive fluids.

Abstract: A flow meter comprising a rotor assembly that is comprised of two rotors having axis of rotation offset from collinear where the two rotors define operating chambers that changing volume with respects to rotation and allow fluid to pass from an inlet port to an outlet port when the number of rotation is indicated the volumetric flow therethrough.

Abstract: A positive displacement device that incorporates two rotors that are offset from collinear and each comprising a first and second set of vanes where the engagement surfaces of the first set of vanes are adapted to only engage when the rotors are in the top dead center location and the second set of lobes of each rotor only engage one another at the bottom dead center position of rotataion.

Abstract: A device to convert energy having exterior and interior rotors where the number of legs (&Lgr;) of an interior rotor divided by the number of chambers (X) defined by the fins of the outer rotor is equal to the effective radius of the inner reference circle r1 divided by the effective radius of the outer reference circle ro (i.e. &Lgr;/X=r1/ro). Where the surface of the fins of the outer rotor and the toe and heel portion of the interior rotor allow for a sealed chamber for a finite amount of rotation of the inner and outer rotors.

Abstract: An improved rotary engine and method for determining the contours of the sealing surfaces thereof. The improved engine provides for maintaining a predetermined, optimal gap between the sealing surfaces during rotation. The gap may be parallel or angled, and may be positive or negative so as to form an interference engagement. The rotors of the engine may be provided with mirror-image sealing surfaces so as to prevent development of excessive back-lash and clearance, and also to permit efficient reverse operation. The sealing surfaces may also be provided with recesses for interrupting the seal at predetermined points in the rotational cycle, for enhanced wear characteristics and/or to accommodate abrasive or shear-sensitive fluids.

Abstract: A rear suspension system for a bicycle. The system directs the rear wheel along a predetermined, S-shaped path as the suspension is compressed. The path is configured to provide a chainstay lengthening effect only at those points where this is needed to counterbalance the pedal inputs of the rider; at those points on the wheel travel path where there is a chainstay lengthening effect, the chain tension which results from the pedal inputs exerts a downward force on the rear wheel, preventing unwanted compression of the suspension. The system employs a dual eccentric crank mechanism mounted adjacent the bottom bracket shell to provide the desired control characteristics.