Electromagnetic actuator, particularly for needle selection devices in machines for knitting, hosiery or the like, with high gauge

Patent metadata

Field	Value
Publication number	US-9328439-B2
Application number	US-201314409585-A
Country	US
Kind code	B2
Filing date	Jun 12, 2013
Priority date	Jun 21, 2012
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

An electromagnetic actuator, particularly for needle selection devices in machines for knitting, hosiery or the like, with high gauge. The electromagnetic actuator comprises a main magnet which has at least two polar regions which are side-by-side and separated by a gap and two selection electromagnets, each provided with at least one polar region which is aligned with the gap and spaced laterally from said gap. The at least one polar region of a selection electromagnet is arranged laterally on the side opposite to the at least one polar region of the other selection electromagnet with respect to the gap. The selection electromagnets can be activated individually to generate or cancel or reduce an attractive magnetic force at the corresponding polar region.

First claim

The invention claimed is:

1. A needle selection device for machines for knitting or hosiery, comprising:
an electromagnetic actuator comprising a main magnet which has at least two polar regions which are side-by-side and separated by a gap,
two selection electromagnets, each one provided with at least one polar region which is aligned with said gap and spaced laterally from said gap, the at least one polar region of a selection electromagnet of said two selection electromagnets being arranged laterally on the side opposite to the at least one polar region of the other selection electromagnet of said two selection electromagnets with respect to said gap, said selection electromagnets configured for activation individually to generate, cancel or reduce an attractive magnetic force at a corresponding polar region of the other selection electromagnet, said at least two polar regions of the main magnet being arranged in sequence along an actuation direction; said needle selection device further comprising selection elements which can be attracted magnetically and can move along said actuation direction with respect to said electromagnetic actuator in order to face in sequence a first polar region of said polar regions of the main magnet, then said gap and said at least one polar region of a selection electromagnet or said at least one polar region of the other selection electromagnet and then a second polar region of said at least two polar regions of the main magnet; said selection elements comprising first selection elements which are adapted to interact with said polar regions of said main magnet and with said at least one polar region of a selection electromagnet, and second selection elements adapted to interact with said polar regions of said main magnet and with said at least one polar region of the other selection electromagnet; said selection elements being movable from a first position, in which they are kept adjacent to said polar regions of the main magnet y the magnetic attraction applied by said polar regions of the main magnet, to a second position, in which they are spaced further from said polar regions of said main magnet than in said first position; the control coil of each one of said selection electromagnets configured to receive electric power in order to keep the selection element interacting with the at least one polar region of the other selection electromagnet in said first position or to allow the passage of the selection element which interacts with the at least one polar region of the other selection electromagnet from said first position to said second position upon its passage at said gap and at said at least one polar region of the other selection electromagnet.

2. The device according to claim 1 , wherein said first selection elements and said second selection elements are alternated along said actuation direction.

3. The device according to claim 1 , wherein each one of said selection elements can move, in order to pass from said first position to said second position, on a plane which is substantially perpendicular to said actuation direction, through the action of elastic means.

4. The device according to claim 1 , wherein faces of said polar regions of the main magnet and of the selection electromagnets directed toward said selection elements are substantially coplanar.

5. The device according to claim 1 , wherein said selection electromagnets are spaced laterally, on mutually opposite sides, from said main magnet.

6. The device according to claim 1 , wherein each one of said selection electromagnets comprises a core made of ferromagnetic material which defines, with one of the core's ends, the at least one polar region of the selection electromagnet and at least one control coil which can be supplied with electric power in order to generate, at said at least one polar region of the selection electromagnet, said attractive magnetic force.

7. The device according to claim 1 , wherein each one of said selection electromagnets comprises a permanent magnet, which is connected magnetically to the corresponding at least one polar region of the selection electromagnet in order to generate, at said at least one polar region of the selection electromagnet, said attractive magnetic force, and at least one control coil configured to receive electric power so as to cancel or reduce said attractive magnetic force at said at least one polar region of the selection electromagnet.

8. The device according to claim 1 , wherein said main magnet comprises a permanent magnet, which is enclosed between two yokes, which define, with ends thereof, two pairs of polar regions, which are separated by said gap.

9. The device according to claim 8 , wherein each one of said two yokes of the main magnet is substantially U-shaped with said gap formed between two ends of the U-shape.

10. The device according to claim 9 , wherein said permanent magnet of the main magnet is interposed between said two yokes proximate to a center region between the two arms of the U-shape of the two yokes.

11. The device according to claim 7 , wherein said permanent magnet, or a core made of ferromagnetic material, of each selection electromagnet is enclosed between two bars, which define, with ends thereof, two polar regions in alignment with each other and with said gap.

12. The device according to claim 11 , wherein said two polar regions of each selection electromagnet are aligned along a direction which is perpendicular to a direction of side-by-side arrangement of the at least two polar regions of said main magnet.

13. The device according to claim 12 , wherein the polar regions of said selection electromagnets are mutually aligned along a direction which is perpendicular to said direction of side-by-side arrangement.

14. The device according to claim 11 , wherein in each selection electromagnet a corresponding control coil is arranged around one of the two bars which define said two polar regions of the corresponding selection electromagnet.

Assignees

• Lonati Andrea
• Santoni & C Spa

Inventors

• Lonati Ettore
• Lonati Fausto
• Lonati Tiberio

Classifications

• D04B15/78 Primary

  Electrical devices · CPC title