BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:
FIG. 1 represents a recirculating ball screw and nut drive with spindle and spindle nut;
FIG. 2 represents a perspective view of a recirculating ball screw and nut drive in a partial section;
FIG. 3 represents an exploded view of a ball deflection piece with the spindle nut;
FIG. 4 represents a ball deflection piece in a top view;
FIG. 5 represents a circular-ring sector of the ball deflection piece from a perspective side view;
FIG. 6 represents a circular-ring sector of the ball deflection piece from a top view;
FIG. 7 represents a circular-ring sector of the ball deflection piece from a side view; and
FIG. 8 represents a snap ring fastening of the ball deflection piece in a section view.
DETAILED DESCRIPTION OF THE INVENTION
The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
FIG. 1 shows diagrammatically a recirculating ball screw and nut drive with a spindle 1 and with a spindle nut 2 guided on the spindle. A working passage is generated between the thread grooves of the spindle 1 and the spindle nut 2, in which working passage the balls (not shown) are guided. The balls are diverted in ball deflection pieces 3 on both ends of the spindle nut 2 out of the working passage into a return passage 4 accommodated in the spindle nut 2, and vice versa.
FIG. 2 shows diagrammatically the recirculating ball screw and nut drive in a perspective view in partial section, where the ball deflection pieces 3 and the return passage 4 are visible. In one embodiment of the present invention, in order to protect the ball deflection piece 3 against twisting, and a radial recess can be provided in the spindle nut body 2, into which the deflection head 7, 8 can be placed, as can be seen, for example, in FIG. 2.
In one embodiment of the present invention, the ball deflection pieces 3 can be annular and are assembled from two substantially identically embodied circular-ring sectors 5 and 6, for example, as shown in FIG. 3. Each circular-ring sector 5, 6 can carry half of a deflection head 7, 8 which projects from the annular ball deflection piece 3, both in the direction of the return passage orifice 4 and on the circumference of the ball deflection piece 3. The deflection head 7, 8 can also be divided in a plane 9 tangential to the spindle 1.
FIG. 4, shows the adjacent circular-ring sectors 5, 6 abut on one another in plane 9. The adjacent circular-ring sectors 5, 6 can be held together by pin 10/blind hole 11 connections, for example, as shown in FIGS. 5 through 7. Before the mounting of the ball deflection piece 3, the pins 10 are introduced into the blind holes 11, and the ball deflection piece 3 is thus inserted into the spindle nut 2 as one piece, in which spindle nut can be fastened with a snap ring 12.
In one embodiment of the present invention, FIG. 4 further shows dirt-scraping tabs 17 which can be integrated into the spindle nut 2.
FIGS. 5, 6, and 7 show the circular-ring sectors 5, seen from a different side view. For example, FIG. 5 shows the parting surface of the circular-ring sector 5. The parts of the ball circulation passages 15, 16 are visible. In one embodiment, after the annular ball circulation piece 3 has been assembled, the parts of the ball circulation passages 15, 16 interact with the parts of the ball circulation passages 15, 16 of the abutting circular-ring sector 6 facing them and generate a ball circulation passage beginning in the working passage defined by grooves provided on the spindle and spindle nut (see, e.g., FIG. 2) and ending before the return passage orifice 4.
FIG. 8 shows a partial cross-sectional view of the spindle nut 2 with the ball deflection piece 3 inserted into an annular groove 13 in the spindle nut 2 and the snap ring 12. In one embodiment, in order to counteract an outward movement of the ball deflection piece 3 out of the spindle nut 2 during operation, the orifice of the annular groove 13 in the spindle nut 2 can have a slanted structure tapering outward. For example, this slanted surface 14 can push back the snap ring 12 holding the ball deflection piece 3 and thus prevent an outward movement.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
Patent Application
20080016973
