A linear drive has at least one rack which is arranged along a longitudinal axis and has a plurality of teeth, a drive shaft arranged in a transverse axis transversely to the longitudinal axis, and at least two propulsion elements, each having at least one propulsion tooth. The at least two propulsion elements are linearly movable in a stroke axis which is oriented transversely to the longitudinal axis and transversely to the drive shaft. The at least two propulsion elements are drivingly coupled to the drive shaft in such a manner that the at least two propulsion elements perform at least one cyclical stroke movement in the course of one rotation of the drive shaft and enter and exit the at least one rack to generate a propulsion in the longitudinal axis. The at least two propulsion elements enter and exit the at least one rack with a phase shift.

A linear drive has at least one rack which is arranged along a longitudinal axis and has a plurality of teeth, a drive shaft arranged in a transverse axis transversely to the longitudinal axis, and at least two propulsion elements, each having at least one propulsion tooth. The at least two propulsion elements are linearly movable in a stroke axis which is oriented transversely to the longitudinal axis and transversely to the drive shaft. The at least two propulsion elements are drivingly coupled to the drive shaft in such a manner that the at least two propulsion elements perform at least one cyclical stroke movement in the course of one rotation of the drive shaft and enter and exit the at least one rack to generate a propulsion in the longitudinal axis. The at least two propulsion elements enter and exit the at least one rack with a phase shift.

A drive mechanism for a medication delivery device containing a resilient member and having a rotation member configured to be rotated in a first direction during setting of a dose of a medication and to be rotated in a second direction during delivery of the dose, where the rotation member is coupled to a drive member that is coupled to a piston rod such that on dose delivery the piston rod is displaced in a distal direction to dispense a medicament and where the resilient member prevents movement of the drive member and the piston rod during dose setting.

A drive mechanism for a medication delivery device containing a resilient member and having a rotation member configured to be rotated in a first direction during setting of a dose of a medication and to be rotated in a second direction during delivery of the dose, where the rotation member is coupled to a drive member that is coupled to a piston rod such that on dose delivery the piston rod is displaced in a distal direction to dispense a medicament and where the resilient member prevents movement of the drive member and the piston rod during dose setting.

Embodiments of the invention provide a pump assembly for a hydraulic tool. The pump assembly can include a reciprocating element that is configured to move between a retracted position and an extended position, a cam surface in the reciprocating element that can engage cam followers, a rotating element that can receive rotational input, and a base that can at least partially surrounds the rotating element. Movement of the cam followers along the cam surface can move the reciprocating element from the retracted position to the extended position.

Provided is a mechanism that causes a rod-shaped member to rotate while causing rod parts, which are part of the rod-shaped member, to carry out out-of-phase reciprocating motions. A drive mechanism (100) in accordance with an aspect of the present invention includes: a rotatable rod (10) that includes rod parts (11) which are separated by a boundary along a central axis 1, the rod parts (11) each being independently movable along the central axis (1); support members (A and B) having a slide groove (31) that is in the form of a ring and that surrounds the rotatable rod (10); and an outer cylinder (50) that is disposed between the rotatable rod (10) and the support members (A and B) and that has longitudinal grooves (51) each extending along the central axis (1).

Provided is a mechanism that causes a rod-shaped member to rotate while causing rod parts, which are part of the rod-shaped member, to carry out out-of-phase reciprocating motions. A drive mechanism (100) in accordance with an aspect of the present invention includes: a rotatable rod (10) that includes rod parts (11) which are separated by a boundary along a central axis 1, the rod parts (11) each being independently movable along the central axis (1); support members (A and B) having a slide groove (31) that is in the form of a ring and that surrounds the rotatable rod (10); and an outer cylinder (50) that is disposed between the rotatable rod (10) and the support members (A and B) and that has longitudinal grooves (51) each extending along the central axis (1).

An actuator assembly is provided for converting rotation into linear displacement including a linear fluid dispensing tube for linear displacement. Hemispherical lugs are monolithically formed on the linear member. A primary gear includes a central bore having helix grooves formed into a surface of the central bore. The helix grooves receive the hemispherical lugs so that each helix groove mates with a respective hemispherical lug to reduce friction, so that hemispherical lugs slide smoothly within the respective helix grooves. Linear projections are formed on the exterior surface of the dispensing tube and extend longitudinally along the dispensing tube. A projecting portion has an aperture for receiving and guiding the dispensing tube through the linear displacement. Mating grooves are formed on an interior of the projecting portion for receiving and guiding the linear projections, thereby preventing the dispensing tube from rotating during travel.

Apparatus is described for administering a substance to a subject. A vial contains the substance and a stopper is disposed within the vial and is slidably coupled to the vial. A first threaded element is (a) rotatable with respect to the vial and (b) substantially immobile proximally with respect to the vial during rotation of the first threaded element. A second threaded element is threadedly coupled to the first threaded element. At least a distal end of the second threaded element is substantially non-rotatable with respect to the vial, and the distal end of the second threaded element defines a coupling portion that couples the second threaded element to the stopper. The first threaded element, by rotating, linearly advances the stopper and at least the distal end of the second threaded element toward a distal end of the vial. Other embodiments are also described.

Apparatus is described for administering a substance to a subject. A vial contains the substance and a stopper is disposed within the vial and is slidably coupled to the vial. A first threaded element is (a) rotatable with respect to the vial and (b) substantially immobile proximally with respect to the vial during rotation of the first threaded element. A second threaded element is threadedly coupled to the first threaded element. At least a distal end of the second threaded element is substantially non-rotatable with respect to the vial, and the distal end of the second threaded element defines a coupling portion that couples the second threaded element to the stopper. The first threaded element, by rotating, linearly advances the stopper and at least the distal end of the second threaded element toward a distal end of the vial. Other embodiments are also described.