초록 ▼

A linear unit (1) comprising a profiled rail ( 2) along which a carriage (3) is arranged for sliding motion backwards and forwards by means of a reversible screw (4) which actuates the carriage and on either side of the carriage passes through a bore (7) in a screw support (8). A pull rod (24) displ

A linear unit (1) comprising a profiled rail ( 2) along which a carriage (3) is arranged for sliding motion backwards and forwards by means of a reversible screw (4) which actuates the carriage and on either side of the carriage passes through a bore (7) in a screw support (8). A pull rod (24) displaces the screw support backwards and forwards along the profiled rail between to end stop positions, and the screw support serves as a support bearing carrying the screw between bearings (10) supporting the screw at its ends. A self-centering device for automatic centering of the screw in the screw support is formed with a self-centering element (11) mounted in the screw-support bore, said element slidingly abutting against the screw both when the screw is rotating in either one of its directions of rotation and when the screw support assumes its end stop positions. The pull rod kinetically interconnects the screw supports located on either side of the carriage, whereby as the carriage is displaced in a sliding motion in one direction it will abut against the screw support located on one side of the carriage for displacement of said screw support from one of its end stop positions to the other one while simultaneously, via the pull rod, bringing along in its movement the screw support located on the other side of the carriage, and reversely.

대표청구항 ▼

The invention claimed is: 1. A device for linear drive units comprising: a profiled rail along which a carriage is arranged for sliding movement backwards and forwards in response to actuation from a threaded screw, said screw arranged to rotate in opposite directions and being drivingly connected

The invention claimed is: 1. A device for linear drive units comprising: a profiled rail along which a carriage is arranged for sliding movement backwards and forwards in response to actuation from a threaded screw, said screw arranged to rotate in opposite directions and being drivingly connected with the carriage and, on either side of the carriage, passing through a through-bore in at least two screw supports, said screw supports being arranged to be displaced by a driver means for movement backwards and forwards along the profiled rail between two end stop positions and forming bearing means carrying said screw intermediate at least two end bearings that support the screw at the ends of the said screw, wherein the driver means kinetically interconnects the screw supports located on either side of the carriage, and wherein the carriage, when being slidingly displaced in one direction, abuts against the screw support on one side of the carriage for displacement of that screw support from one of the end stop positions, said carriage simultaneously, by means of the driver means bringing, along in its movement of the screw support located on the other side of the carriage, and reversely. 2. The device as claimed in claim 1, wherein the driver means is fixedly attached to the screw supports and extends freely past the carriage. 3. The device as claimed in claim 1, wherein the driver means is a pull rod having free ends of which are attached to the associated screw support and which pull rod intermediate its attachment ends are guided in the profiled rail of the linear unit beyond and spaced from the carriage. 4. The device as claimed in claim 3, wherein the pull rod is fitted into an elongate guide means in the profiled rail of the linear unit to be guided therein, a guide portion of the rod that is located in the guide means and the guide means being configured with essentially complementary profile shapes. 5. The device as claimed in claim 4, wherein the free attachment ends of the pull rod form an angle to the guide portion of the rod and wherein intermediate each one of its attachment ends and the guide portion, said pull rod is formed with a transitional portion passing through an elongate recess that is formed in the guide means and is open towards the screw supports. 6. The device as claimed in claim 5, wherein said transitional portion and the recess have smaller dimensions than the guide portion and the guide means. 7. The device as claimed in claim 1, wherein there are at least two screw supports pairs arranged in pairs on either side of the carriage, and wherein the screw supports of a first pair closest to the carriage on either side thereof are kinetically interconnected by means of a first pull rod and a screw support of at least one second pairs located beyond the first at least one pairs, are kinetically interconnected in pairs by means of one further pull rod each, whereby displacement of one of the screw supports of the first pair in response to actuation thereon by the carriage, will result in abutment of that screw support against the closest screw support of said second pair for displacement of both of said supports and their respective pair, and reversely as the carriage is displaced in a sliding motion in the opposite direction. 8. The device as claimed in claim 1, wherein a self-centering element located in the through-bore of the screw support is provided, which element has sliding abutment contact with the screw both when the screw is rotating in one or the other of its directions and when the screw supports assume their end stop positions, in order to self-center the screw in the screw support. 9. The device as claimed in claim 8, wherein the self-centering element is configured as a slide member that slides on top of the outer periphery of the screw. 10. The device as claimed in claim 9, wherein the slide member is formed by a plate, which extends essentially in the lengthwise direction of the screw and which is resiliently biased in an essentially radial direction towards the screw. 11. The device as claimed in claim 8, wherein several slide members are provided, said members being evenly spaced and/or arranged in one or several groups around the screw. 12. The device as claimed in claim 9, wherein the slide member is formed by a sleeve, said sleeve extending in the longitudinal direction of the screw and enclosing said screw and being resiliently biased in an essentially radial direction towards the screw. 13. The device as claimed in claim 12, wherein the sleeve is positioned in a gap between the through-bore of the screw support and the outer periphery of the screw. 14. The device as claimed in claim 13, wherein at its inner face, the sleeve slidingly abuts against the outer periphery of the screw whereas at its outer face said screw is resiliently biased in an essentially radial direction towards the screw by means of at least one spring means directed in an essentially radial direction towards the screw. 15. A device for linear-drive units comprising: a profiled rail along which a carriage is arranged for sliding movement backwards and forwards in response to actuation from a threaded screw, said screw arranged to rotate in opposite directions and being drivingly connected with the carriage and, on the other side of the carriage, passing through a through-bore, in at least two screw supports, said screw supports being arranged to be displaced by a pull rod for movement backwards and forwards along the profiled rail between two end stop positions and forming bearing means carrying said screw intermediate at least two end bearings that support the screw at the ends of the said screw, wherein the pull rod kinetically interconnects the screw supports located on either side of the carriage and wherein the carriage, when being slidingly displaced in one direction, will abut against the screw supports on one side of the carriage for displacement of that screw support from one of the end stop positions of the said screw to the other end stop position, said carriage simultaneously by the pull rod brings along its movement of the screw support located on the other side of the carriage, and reversely. 16. The device as claimed in claim 15, wherein the pull rod is fixedly attached to the screw supports and extends freely past the carriage. 17. The device as claimed in claim 15, wherein the pull rod has free ends which are attached to the associated screw supports and the free ends are guided in the profiled rail spaced from the carriage.