Linear traversing carriage incorporating an air gap inductive motivator

• US 7,535,187 B2
• Filed: 02/14/2007
• Issued: 05/19/2009
• Est. Priority Date: 02/16/2006
• Status: Expired due to Fees

• Current Assignee: Kadant Incorporated
• Original Assignee: Kadant Incorporated
• Inventors: Carstensen, Peter T.
• Primary Examiner(s): Ro; Bentsu
• Assistant Examiner(s): Luo; David S
• Application Number:
  US11/705,994
• Publication Number:
  US 20070200514A1
• Time in Patent Office: 825 Days
• Field of Search: 318/135, 226/92, 101/216
• US Class Current: 318/135
• CPC Class Codes: H02K 41/025 Asynchronous motors
• CPC Class Codes: H02P 25/06 Linear motors
• CPC Class Codes: H02P 25/062 of the induction type

Abstract

The present invention relates to a linear traversing carriage for use in the papermaking industry and the like, which incorporates an air gap inductive motivator and eliminates all mechanical devices between the electrical power supply and the traversing mechanism. Specifically, the present invention relates to a linear traversing device comprising an inductor type linear motor comprising an electrical stator winding, a conductive platen extending over an entire traverse length of the device, a ferromagnetic material affixed to said conductive platen, a support means for supporting the device and maintaining an air-gap between the stator winding and the conductive platen, a user selected feed forward velocity map for driving the device, a controller that controls a movement of the device according to the user selected feed forward velocity map.

Claims

1. A linear traversing device comprising:

an inductor type linear motor comprising an electrical stator winding;

a conductive platen extending over an entire traverse length of the device;

a ferromagnetic material affixed to said conductive platen;

a support means for supporting the device and maintaining an air-gap between the stator winding and the conductive platen;

a user selected feed forward geometric velocity map for driving the device,

a controller that controls a movement of the device according to the user selected feed forward velocity map.

2. The linear traversing device according to claim 1, wherein the controller is a numeric comparator control algorithm for movement of the device.

3. The linear traversing device according to claim 1, wherein a velocity of the device is controllable.

4. The linear traversing device according to claim 1, wherein a direction of movement of the device is controllable.

5. The linear traversing device according to claim 1, wherein a position of the device is defined by the user selected feed forward geometric velocity map to minimize excessive heating of said stator winding.

6. The linear traversing device according to claim 1, wherein the stator winding is powered at a user selected Pulse Width Modulated (“

PWM”

) AC electrical power signal.

7. The linear traversing device according to claim 6, wherein said PWM AC electrical power signal is a selected sympathetic harmonic of a system magnetic resonance frequency in real time.

8. The linear traversing device according to claim 1, wherein the conductive platen has a continuous electrical path over the entire traverse length.

9. The linear traversing device according to claim 1, wherein the conductive platen has high electrical conductivity.

10. The linear traversing device according to claim 1, wherein the conductive platen is shaped to maximize a magnetic field developed in a transverse direction.