DEVICE FOR TRANSFORMING A ROTATIONAL MOTION INTO A TRANSLATIONAL MOTION

• US 3,824,420 A
• Filed: 04/06/1973
• Issued: 07/16/1974
• Est. Priority Date: 03/04/1970
• Status: Expired due to Term

• Current Assignee: Bernardus Hendrikus Marinus Johannes Stegeman, Hilrich Jan Matthijs Venker
• Original Assignee: Bernardus Hendrikus Marinus Johannes Stegeman, Hilrich Jan Matthijs Venker
• Inventors: Venker, Hilrich Jan Matthijs, Stegeman, Bernardus Hendrikus Marinus Johannes
• Primary Examiner(s): Budd, Mark O.
• Application Number:
  US05/348,600
• Time in Patent Office: 466 Days
• Field of Search: 310/97,99,103,104,14,15,23,80,83,84,155,166,12,266 74/DIG.4,22A,424.8R,210,409
• US Class Current: 310/80
• CPC Class Codes: B41J 19/20 Positive-feed character-spacing mechanisms controlled by escapements B41J19/52
• CPC Class Codes: B41J 29/38 Drives, motors, controls or automatic cut-off devices for the entire printing mechanism
• CPC Class Codes: F16H 25/20 Screw mechanisms with automatic reversal F16H25/12
• CPC Class Codes: H02K 49/06 of the synchronous type H02K49/10 takes precedence
• CPC Class Codes: H02K 7/06 Means for converting reciprocating motion into rotary motion or vice versa
• CPC Class Codes: Y10T 74/18696 including means to selectively transmit power [e.g., clutch, etc.]

Abstract

A motion transforming device wherein selectively energizable magnetic coupling is provided between the threads of a screw and a nut engaged therewith.

Claims

1. In a device for transforming a rotational motion into a translational motion, wherein a male element engages in at least one female and is substantially coaxial with said female element, said male and female elements being provided with flat crested threads of the same pitch and of the same sense on their opposed walls and being caused to have a relative rotational motion therebetween when one of said elements is prevented from turning in order that it be displaced relative to the other, the improvement comprising:

said male and female elements being formed at least partially of magnetic material, the external diameter of the thread of said male element being less than the smallest diameter between crests of the thread of said female element, said one element prevented from rotating having a central annular recess separating into two portions the threads of that member, and a single energizing winding in said recess for generating a flux closing through said male and female elements.

2. The device of claim 1, further comprising elastic restoring means stressed by the movable translation element when it slides relative to the other element.

3. The device of claim 1, wherein threads of said male and female elements have dimensions such that, when said coil is energized, the movable translation element almost instantaneously reaches a position in which the crests of its thread are disposed opposite the crests of the thread of the other element.

4. The device of claim 1, wherein said female element has the form of a nut and is traversed by said male element, said male element being in the form of a screw, wherein said nut is prevented from turning but not from translating, and wherein said screw can be turned but is prevented from longitudinal translation.

5. The device of claim 1, wherein said female element has the form of a nut and is traversed by said male element, said male element being in the form of a screw, wherein said nut is prevented from turning and from translating, and wherein said screw can be turned and can slide in longitudinal translation.

6. The device of claim 1, wherein said female element is a tubular sleeve having an internal thread, wherein a male element comprising a threaded magnetic core is inserted in said sleeve, wherein said core is prevented from turning but not from translating, and wherein said sleeve can be turned on its axis but is prevented from longitudinal translation.

7. The device of claim 1, wherein said female element is a tubular sleeve having an internal thread, wherein a male element comprising a threaded magnetic core is inserted in said sleeve, wherein said core is prevented from turning and from translating, and wherein said sleeve can be turned and can slide in longitudinal translation.

8. The device of claim 1, comprising an additional like male element and an additional like female element bearing, said female elements being joined together, and an additional coil, said two coils being alternatively supplied with current, one coil being associated with one direction of translation of the two joined female elements and the other coil being associated with the opposite direction.

9. The device of claim 1, wherein said female element comprises a tubular magnetic yoke in which are mounted two half-nuts, one on each side of a coil, said yoke being closed at its ends by non-magnetic side plates provided with openings traversed by said male element by which said female element can be entered and can slide with light friction relative to said male element.

10. The device of claim 9, wherein said side plates comprise extensions cooperating with a guide shaft disposed parallel to said male element for preventing said female element from turning.

11. The device of claim 8, wherein said two male elements have threads of the same sense and are turned in opposite directions.

12. The device of claim 2, wherein said female element has the form of a nut and is traversed by said male element, said male element being in the form of a screw, wherein said nut is prevented from turning but not from translating, and wherein said screw can be turned but is prevented from longitudinal translation.

13. The device of claim 2, wherein said female element has the form of a nut and is traversed by said male element, said male element being in the form of a screw, wherein said nut is prevented from turning and from translating, and wherein said screw can be turned and can slide in longitudinal translation.

14. The device of claim 2, wherein said female element is a tubular sleeve having an internal thread, wherein a male element comprising a threaded magnetic core is inserted in said sleeve, wherein said core is prevented from turning but not from translating, and wherein said sleeve can be turned on its axis but is prevented from longitudinal translation.

15. The device of claim 2, wherein said female element is a tubular sleeve having an internal Thread, wherein a male element comprising a threaded magnetic core is inserted in said sleeve, wherein said core is prevented from turning and from translating, and wherein said sleeve can be turned and can slide in longitudinal translation.

16. A device for transforming a rotational motion into a translational motion, comprising:

A first element having cylindrical outer surface and bearing a first thread on said outer surface, a second element having a cylindrical inner surface and a bearing a second thread on said inner surface, said first and second threads having the same pitch, the outer diameter of said first thread being less than the inner diameter of said second thread, said first and second elements being formed at least partially of magnetic materials, said first element being at least partially disposed inside said second element such that said first and second threads are opposed, turning means for turning one of said elements about the central axis of the respective cylindrical surface thereof, restraining means for restraining the other one of said elements from turning, supporting means for supporting said first and second elements to enable one of said elements to move relative to the other in a direction substantially parallel to said central axis, one only of said male and female elements having a central annular recess separating the thread thereof into two spaced portions, a single energizing winding in said central recess for generating a magnetic field linking at least said first and second thread, and control means for selectively energizing said winding.

17. The device of claim 16, wherein said turning means turns said first element, said restraining means restrains said second element, and said supporting means supports said second element to move parallel to said axis.

18. The device of claim 16, wherein said turning means turns said first element, said restraining means restrains said second element, and said supporting means supports said first element to move parallel to said axis.

19. The device of claim 16, wherein said turning means turns said second element, said restraining means restrains said first element, and said supporting means supports said first element to move parallel to said axis.

20. The device of claim 16, wherein said turning means turns said second element, said restraining means restrains said first element, and said supporting means supports said second element to move parallel to said axis.

21. The device of claim 16, wherein said control means energizes said winding to provide movement of one of said elements relative to the other in a first direction parallel to said axis and deenergizes said winding when said movement in said first direction is to cease.

22. The device of claim 21, further including means to provide movement of one of said elements relative to the other in a second direction opposite to said first direction when said winding is deenerized.

23. A gearing apparatus for transforming a rotational movement into a translational movement comprising:

a male element, a female element both made of a ferrous metal and being provided with flat-crested helicoidal threads of same sense and pitch on their external and internal diameters respectively, guiding means connected to said male element and said female element for maintaining said male element coaxial with said female element for preventing any rotational movement of said female element, and for preventing any axial displacement of said male element, driving means for rotating said male element, said female element being provided with an annular internal cavity separating in two substantially equal portions the threads of said female element, and one winding wound coaxially into said cavity and energized to generate a magnetic flux which closes through the threads of said male and female elements.

24. A gearing apparatus according to claim 23, further comprising elastic restoring mEans connected to said female element for stressing thereby when said female element slides relative to said male element.

25. A gearing apparatus for transforming a rotational movement into a translational movement comprising a female element made of ferrous metal having a bore with an internal helicoidal threading with flat crests, a fixed male element made of ferrous metal having a core section provided with an external flat-crested helicoidal threading with same sense and pitch as that of said female element, said core section being fitted with a single annular cavity separating the threads of said core section in two sections of substantially equal lengths, a coil winding wound coaxially into said cavity and energized to generate a magnetic flux closing through the threads of said core sections and of said female element, and driving means for rotating said female element while permitting axial displacement thereof, and guiding means connected to said male element and said female element for maintaining said male element coaxial with said female element, for permitting rotation and axial displacement of said female element, and for preventing rotation of said male element.

26. A gearing apparatus as claimed in claim 25, further comprising elastic restoring means connected to said female element for stressing thereby when said female element slides relative to said male element.

27. A bearing apparatus for transforming a rotational movement into translational movements, comprising:

two screw members made of ferrous metal each with identical external helicoidal threading with flat crests, driving means for rotating said screw members in opposite directions of rotation, guiding means for maintaining both of said screw members in parallel relation and for preventing their axial displacement, a female element made of ferrous metal provided with two bores into which said screw members are engaged without rubbing, each of said bores being fitted with internal threading similar to that of the corresponding screw member and with an annular cavity disposed to separate the threads of said bore into two sections of substantially equal lengths, a coil winding wound coaxially into each of the said cavities of said female element, and switching means for selectively energizing either of said windings to cause axial displacement in either of two opposite directions of said femal element by generating a magnetic flux which closes through the threads of the corresponding bore and screw member.