DISENGAGEABLE NUT AND SCREW ARRANGEMENT

• US 3,757,591 A
• Filed: 09/30/1971
• Issued: 09/11/1973
• Est. Priority Date: 09/30/1970
• Status: Expired due to Term

• Current Assignee: Peter Graham Taylor
• Original Assignee: Peter Graham Taylor
• Inventors: Taylor, Peter Graham
• Primary Examiner(s): Myhre, Charles J.
• Assistant Examiner(s): Ratliff, Jr., Wesley S.
• Application Number:
  US05/185,258
• Time in Patent Office: 712 Days
• Field of Search: 74/89.15,424.8A 33/165
• US Class Current: 74/424.78
• CPC Class Codes: F16H 25/20 Screw mechanisms with automatic reversal F16H25/12
• CPC Class Codes: F16H 25/2025 with means to disengage the nut or screw from their counterpart; Means for connecting screw and nut for stopping reciprocating movement F16H25/2015 takes precedence
• CPC Class Codes: Y10T 74/19735 Nut disengageable from screw

Abstract

A nut and screw arrangement particularly for scientific instruments having a lead nut and screw in which the nut has two bores inclined with one another, the one plain and the other screw threaded and means for tilting the nut into and out of engagement of the lead screw so that part of the apparatus may be advanced finely by the screw and coarsely manually.

Claims

1. In combination with a precision instrument, an adjusting mechanism comprising an externally threaded fine adjusting screw rotatable about its longitudinal axis, a nut having at least a partially threaded bore interengaging with said screw through which an axial force may be transmitted to said nut upon rotation of said screw, said nut including a smooth bore having a diameter larger than the diameter of said screw extending therethrough at an angle to said partially threaded bore and having an axis which intersects the axis of said partially threaded bore at substantially the midpoint thereof, means for rotating said nut about a tilting axis extending through said point of intersection and perpendicular to the axis of said screw for selectively aligning said screw with either said partially threaded bore or said smooth bore, whereby said nut may be slid axially over said screw when said smooth bore is aligned with said nut and said nut may be translated relative to said screw upon rotation thereof when said partially threaded bore is aligned with said screw, the resultant of the force transmitted by said screw to said nut upon rotation of said screw passing through said tilting axis.

2. The combination of claim 1 wherein said adjusting screw is disposed vertically.

3. The combination of claim 1 wherein said precision instrument is a sledge microtome.