Air-core armature

• US 3,944,857 A
• Filed: 09/19/1974
• Issued: 03/16/1976
• Est. Priority Date: 02/28/1974
• Status: Expired due to Term

• Current Assignee: Retobina Handelsanstalt
• Original Assignee: Retobina Handelsanstalt
• Inventors: Faulhaber, Fritz
• Primary Examiner(s): Budd, Mark O.
• Application Number:
  US05/507,623
• Time in Patent Office: 544 Days
• Field of Search: 310/200-208, 310/265, 310/266, 310/268
• US Class Current: 310/266
• CPC Class Codes: H02K 3/26 consisting of printed conductors

Abstract

An air-core armature for electrodynamic machines comprises an elongated insulating strip rolled up to form a spiral structure composed of a plurality of radially successive layers. An armature winding is comprised of at least one armature coil. The armature coil is comprised of a plurality of electrically interconnected (e.g., series connected or parallel-connected) component coils. Each of the component coils is formed of electrically interconnected conductor sections printed on both sides of the insulating strip. The component coils are located on different respective ones of the radially successive layers of the spiral structure, but occupy substantially the same circumferential sector of the spiral structure, and accordingly are substantially juxtaposed in direction radially of the spiral structure.

Claims

1. An air-core armature for electrodynamic machines, comprising, in combination, an elongated insulating strip rolled up to form a spiral structure composed of a plurality of radially successive layers;

and an armature winding comprised of at least one armature coil, said armature coil being comprised of a plurality of electrically interconnected component coils, each of said component coils being formed of electrically interconnected conductor sections printed on both sides of said strip, said component coils being located on different respective ones of said radially successive layers but occupying substantially the same circumferential sector of said spiral structure and accordingly being substantially juxtaposed in direction radially of said spiral structure, wherein each of said component coils has one end and an other end, and is comprised at said other end of a circumferentially extending electrically conductive portion extending in the circumferential direction opposite to the direction from said one end to said other end, said circumferentially extending electrically conductive portions being so disposed as to compensate for the difference in circumferential length of different ones of said radially successive layers.

2. An armature as defined in claim 1, wherein the circumferentially extending electrically conductive portions of radially juxtaposed component coils located on neighboring layers of said spiral structure together extend over a circumferential distance substantially equal to the circumferential width of one component coil.

3. An armature as defined in claim 1, wherein said circumferentially extending electrically conductive portions are electrically connected to each other by means of an overhead connection.

4. An armature as defined in claim 3, wherein each of said circumferentially extending electrically conductive portions is electrically connected to said overhead connection through the intermediary of a respective island-like electrically conductive portion located on the respective layer of said spiral structure and printed onto one side of said insulating strip.

5. An air-core armature for electrodynamic machines, comprising, in combination, an elongated insulating strip rolled up to form a spiral structure composed of a plurality of radially successive layers;

and an armature winding comprised of at least one armature coil, said armature coil being comprised of a plurality of electrically interconnected component coils, each of said component coils being formed of electrically interconnected conductor sections printed on both sides of said strip, said component coils being located on different respective ones of said radially successive layers but occupying substantially the same circumferential sector of said spiral structure and accordingly being substantially juxtaposed in direction radially of said spiral structure, wherein said plurality of component coils includes two component coils each having a first end and a second end, the first end being the end through which electric current flows into the respective component coil and the second end being the end through which electric current flows out of the respective component coil, and wherein one of said component coils is comprised at said second end of a circumferentially extending electrically conductive portion extending in the circumferential direction opposite to the direction from the respective first end to the respective second end, and wherein the other of said two component coils is comprised at said first end of a circumferentially extending electrically conductive portion extending in the circumferential direction opposite to the direction from the respective second end to the respective first end, said circumferentially extending electrically conductive portions being so disposed as to compensate for the difference in circumferential length of different ones of said radially successive layers.

6. An air-core armature for electrodynamic machines, comprising, in combination, an elongated insulating strip rolled up to form a spiral structure composed of a plurality of radially successive layers;

and an armature winding comprised of at least one armature coil, said armature coil being comprised of a plurality of electrically interconnected component coils, each of said component coils being formed of electrically interconnected conductor sections printed on both sides of said strip, said component coils being located on different respective ones of said radially successive layers but occupying substantially the same circumferential sector of said spiral structure and accordingly being substantially juxtaposed in direction radially of said spiral structure, wherein said armature winding is a lapped winding, and wherein said winding sections are comprised of axially extending electrically conductive portions, and wherein each such winding section has a circumferential length which, compared to the circumferential length of a winding section not comprised of such axially extending electrically conductive portions, is given by the formula.

space="preserve" listing-type="equation">w = 0.55 (h/d).sup.1/3

where h and d are respectively the height and diameter of said spiral structure.

7. An air-core armature for electrodynamic machines, comprising, in combination, an elongated insulating strip rolled up to form a spiral structure composed of a plurality of radially successive layers;

and an armature winding comprised of at least one armature coil, said armature coil being comprised of a plurality of electrically interconnected component coils, each of said component coils being formed of electrically interconnected conductor sections printed on both sides of said strip, said component coils being located on different respective ones of said radially successive layers but occupying substantially the same circumferential sector of said spiral structure and accordingly being substantially juxtaposed in direction radially of said spiral structure, wherein said armature winding is a lapped winding, and wherein said winding sections are comprised of axially extending electrically conductive portions of greater breadth connecting together inclined electrically conductive portions of lesser breadth, and wherein said axially extending electrically conductive portions of greater breadth are each provided with at least one axially extending slit to reduce the flow of eddy currents in the material of said axially extending electrically conductive portions without greatly increasing the electrical resistance thereof.

8. An air-core armature for electrodynamic machines, comprising, in combination, an elongated insulating strip rolled up to form a spiral structure composed of a plurality of radially successive layers;

and an armature winding comprised of at least one armature coil, said armature coil being comprised of a plurality of electrically interconnected component coils, each of said component coil being formed of electrically interconnected conductor sections printed on both sides of said strip, said component coils being located on different respective ones of said radially successive layers but occupying substantially the same circumferential sector of said spiral structure and accordingly being substantially juxtaposed in direction radially of said spiral structure, wherein said armature further includes insulating material electrically insulating from each other the winding sections on the facing sides of neighboring ones of said radially successive layers, but the radially inner side of the innermost one of said layers and the radially outer side of the outermost one of said layers not being provided with said insulating material and instead being blackened for the purpose of reducing heat radiation.