Abstract: The invention relates to a process for determining the form a duplicate of a residual tooth area, which is to be fitted with a dental restoration whereby the duplicate sections to be fitted with the restoration are removed from the duplicate and the form data to be allocated to their forms has to be determined and stored in a computer, by means of which the form of the restoration is calculated taking into consideration the spatial allocation of the duplicate sections. In order to be able to determine the shape of the residual tooth area to be fitted with the restoration, and thereby determine the shape of the restoration itself with high precision, it is proposed that the duplicate sections are or are being individually referenced to each other in their spatial allocation to each other according to a referencing stored in the computer.

Abstract: The invention relates to a method for three-dimensional shape measurement of a body or of a part thereof, in particular of a dental object such as a model, by scanning non-contact distance measurement using an optical sensor device comprising a beam source, where the shape of the body subjects reproducing areas to a beam at various incidence angles (impinging beam), and the reflected beam (measuring beam) is measured, with the body being adjusted relative to the optical sensor device. To permit measurement with high precision of the body and undercuts thereof, without tilting being necessary, it is proposed that for shape measurement of the respectively measured area the beam (measuring beam) reflected therefrom, which describes an angle ? to a surface normal corresponding to the respective area, is taken into account, said angle being equal to or smaller than a predefined critical angle ?GR relative to the surface normal.

Abstract: The invention refers to a procedure for manufacturing a dental object (24), whereby the object is brought out of a mold blank (26) via machine cutting, and the working is completed with the splitting of a circulating partition wall (32) or a membrane, which runs between the completely worked object and the remaining mold blank.

Abstract: The invention relates to a process for determining the form a duplicate of a residual tooth area, which is to be fitted with a dental restoration whereby the duplicate sections to be fitted with the restoration are removed from the duplicate and the form data to be allocated to their forms has to be determined and stored in a computer, by means of which the form of the restoration is calculated taking into consideration the spatial allocation of the duplicate sections. In order to be able to determine the shape of the residual tooth area to be fitted with the restoration, and thereby determine the shape of the restoration itself with high precision, it is proposed that the duplicate sections are or are being individually referenced to each other in their spatial allocation to each other according to a referencing stored in the computer.

Abstract: A method for aligning digitized dentures displayed on a screen using an input device and a rectangular coordinate system with X, Y and Z axis. The aim of the invention is to provide a method which allows the intuitive and simple alignment of virtual models of teeth or rows of teeth or dentures within the scope of visualizing scan data and the CAD modeling of dentures. For this purpose, the Z axis of the coordinate system extends in the plane of the screen and the X axis extends perpendicularly thereto. The origin of the coordinate system intersects the object displayed on the screen and the object is aligned on the screen by a maximum of five degrees of freedom.

Abstract: A mobile invalid hoist comprises a non-rectilinear lifting arm pivotably connected about first horizontal axis to the upper end of mast, a housing pivotably connected about second horizontal axis to one end of the lifting arm and supporting a vertical bearing, a sling hanger support pivotably supported about a vertical or substantially vertical axis by the bearing, and a sling hanger pivotably supported about a third horizontal axis by the sling hanger support. A flexible elongate element is connected between the mast and housing, and is guided through the lifting arm to effectively form with the lifting arm a parallelogram linkage. Thus, as the lifting arm pivots, the housing pivots in relation to the lifting arm and the bearing is kept vertical or substantially vertical.

Abstract: An invalid hoist includes a lifting arm, an actuator between the lifting arm and a mast, the lifting arm being pivotably connected to the upper end of the mast at a position intermediate its ends and the actuator being connected to the lifting arm on the side of the pivotable connection between the lifting arm and the mast remote from said one end of the lifting arm, and a connecting link pivotably connected between one end of the actuator and the lifting arm (or mast). The connecting link is connected between the actuator and the lifting arm (or mast) such that an auxiliary link incorporating a load cell can be additionally and removably connected between the actuator and the lifting arm (or mast) and such that any load applied to the lifting arm is transmitted entirely through the auxiliary link.

Abstract: An invalid positioning device comprising a support structure, a lifting element which is angularly displaceable about a main horizontal axis relative to the support structure, and a power operated mechanism for pivoting the lifting element about the the main horizontal axis. The power operated mechanism is arranged such that the torque applied by the power operated mechanism decreases as the lifting element moves away from one extreme position and increases again as the lifting element approaches its other extreme position and such that the angular speed of the lifting element increases as it moves away from one extreme position and decreases as it approaches its other extreme position.

Abstract: A mobile invalid hoist comprises a non-rectilinear lifting arm pivotably connected about first horizontal axis to the upper end of mast, a housing pivotably connected about second horizontal axis to one end of the lifting arm and supporting a vertical bearing, a sling hanger support pivotably supported about a vertical or substantially vertical axis by the bearing, and a sling hanger pivotably supported about a third horizontal axis by the sling hanger support. A flexible elongate element is connected between the mast and housing, and is guided through the lifting arm to effectively form with the lifting arm a parallelogram linkage. Thus, as the lifting arm pivots, the housing pivots in relation to the lifting arm and the bearing is kept vertical or substantially vertical.

Abstract: An invalid hoist includes a lifting arm, an actuator between the lifting arm and a mast, the lifting arm being pivotably connected to the upper end of the mast at a position intermediate its ends and the actuator being connected to the lifting arm on the side of the pivotable connection between the lifting arm and the mast remote from said one end of the lifting arm, and a connecting link pivotably connected between one end of the actuator and the lifting arm (or mast). The connecting link is connected between the actuator and the lifting arm (or mast) such that an auxiliary link incorporating a load cell can be additionally and removably connected between the actuator and the lifting arm (or mast) and such that any load applied to the lifting arm is transmitted entirely through the auxiliary link.

Abstract: An invalid positioning device comprising a support structure, a lifting element which is angularly displaceable about a main horizontal axis relative to the support structure, and a power operated mechanism for pivoting the lifting element about the said main horizontal axis. The power operated mechanism is arranged such that the torque applied by the power operated mechanism decreases as the lifting element moves away from one extreme position and increases again as the lifting element approaches its other extreme position and such that the angular speed of the lifting element increases as it moves away from one extreme position and decreases as it approaches its other extreme position.

Abstract: An invalid hoist comprises a mast, a lifting arm which can be raised and lowered by telescopically extending and retracting the mast and/or by raising and lowering a carriage, which may support the lifting arm, relative to the mast, and a load cell on the lifting arm for providing a signal representative of the weight of a person being lifted. The lifting arm is connected to the mast or the carriage by an arrangement which allows the lifting arm to be displaced angularly in a vertical plane against a spring force in order to maintain the load cell in a constant orientation as a vertical load is applied to the lifting arm.

Abstract: A carriage, such as an invalid hoist or shopping trolley, is mounted on castors. Each castor is swivellable about a first axis. At least one of the castors is supported by a support element which is angularly displaceable about a second axis parallel to the intended direction of fore and aft movement of the carriage. The first axis is perpendicular or substantially perpendicular to the second axis. Means are provided for angularly displacing the support element about the second axis to encourage the castor supported thereby to swivel one way or the other according to the direction in which the support element is angularly displaced and to steer the carriage when the latter is propelled along the ground.

Abstract: A chassis comprises two legs extending in parallel spaced apart relationship and a cross member connecting the two legs together. The cross member comprises first, second and third tubular members. The second member is telescopically extendible and retractable in the first member and the third member is telescopically extendible and retractable in the second member. A linear actuator is provided for extending and retracting the second and third members in opposite directions relative to the first member.

Abstract: The invalid lifting device comprises a first mast upstanding from a first elongate chassis member and a second mast upstanding from a second elongate chassis member which is parallel or substantially parallel to the first chassis member. The lifting device also comprises a lifting arm supported by and extending between the first and second masts, the lifting arm comprising two parts pivotable relative to one another so that the distance between the masts can be varied. One part is supported by the first mast and the other part is supported by the second mast. Power operated means are provided for moving the two chassis members towards and away from one another. Each part of the lifting arm comprises a parallelogram linkage to maintain the chassis members in parallel or substantially parallel relationship as the two chassis members are moved towards and away from one another.

Abstract: The invalid lifting device comprises a first mast upstanding from a first elongate chassis member and a second mast upstanding from a second elongate chassis member which is parallel or substantially parallel to the first chassis member. The lifting device also comprises a lifting arm supported by and extending between the first and second masts, the lifting arm comprising two parts pivotable relative to one another so that the distance between the masts can be varied. One part is supported by the first mast and the other part is supported by the second mast. Power operated means are provided for moving the two chassis members towards and away from one another. Each part of the lifting arm comprises a parallelogram linkage to maintain the chassis members in parallel or substantially parallel relationship as the two chassis members are moved towards and away from one another.