Robert A Pulford

US Patent:

61462802, Nov 14, 2000

Filed:

Sep 29, 1995

Appl. No.:

8/536654

Inventors:

Robert Pulford - Wolcott CT

Assignee:

Tri-Tech, Inc. - Waterbury CT

International Classification:

F16D 316

US Classification:

464112

Abstract:

A flexible joint for first and second rotating members, including: a hub fixedly connected to a proximal end of the first rotating member at a first end of the hub; the hub being constructed for the insertion in a second, opposite end of the hub of a proximal end of the second rotating member, the proximal end of the second rotating member being moveable within the hub such that a distal end of the second rotating member may move axially with respect to the first rotating member and/or may move radially away from a major axis of the first rotating member; and a spring disposed between an end face of the proximal end of the second rotating member and an inner face of the hub to bias the second rotating member axially away from the hub and the first rotating member, strength of the spring determining the ease with which the distal end of the second rotating member may move.

US Patent:

59101920, Jun 8, 1999

Filed:

Sep 8, 1997

Appl. No.:

8/925189

Inventors:

Robert Pulford - Wolcott CT
Richard Donnelly - Wallingford CT
Brian Peterson - Woodbury CT

Assignee:

Tri-Tech., Inc. - Waterbury CT

International Classification:

G05G 1100

US Classification:

7447901

Abstract:

In a preferred embodiment, a linear positioning device, including: a frame member; an electric motor disposed to selectively move axially back and forth in the frame member; carriage apparatus attached to the electric motor; and apparatus to guide the motor in axial movement and to prevent radial movement thereof. In a further aspect of the invention, there is provided a frame for a linear positioning device, including: a horizontal base plate; vertical end plates for attachment to ends of the base plate; the base plate including a first groove defined in the surface thereof for the mounting therein of a guide rail for a moving member; and the base plate is cut from an extrusion which includes the first groove, without the machining thereof. In another aspect of the invention, there is provided, in a linear positioning device, having the front end plate of an electric motor as an end plate of the device. In an additional aspect of the invention, there is provided, in a positioning device, having an electric motor fixedly mounted to an end plate of the device.

US Patent:

6150789, Nov 21, 2000

Filed:

Jun 1, 1999

Appl. No.:

9/323467

Inventors:

Robert Pulford - Wolcott CT

Assignee:

Tri-Tech, Inc. - Waterbury CT

International Classification:

G05B 1940

US Classification:

318685

Abstract:

In a preferred embodiment, a stepper motor control, including: a driver to drive the stepper rotor; a detector to detect a commanded step rate signal provided to the driver and to provide an output signal proportional thereto; a power control, responsive to the output signal, to provide driving power to the driver, and to increase voltage to the driver in proportion to an increase in magnitude of the output signal; and an over-current protection circuit that becomes active above a predetermined motor current level and above a predetermined commanded step rate. Voltage control can be effected either on the drive board or by controlling the power supply. An additional feature provides over-current protection for the stepper motor during a lock rotor (stall) condition. The stepper motor control produces very low levels of EMI/RFI as compared with PWM current control (chopper) drives.

US Patent:

20010033110, Oct 25, 2001

Filed:

Feb 12, 2001

Appl. No.:

09/783179

Inventors:

Robert Pulford - Wolcott CT, US

International Classification:

H02K041/00

US Classification:

310/012000

Abstract:

In a preferred embodiment, linear stepper motor, comprising; an annular stator structure; an axially extending, cylindrical, permanent magnet shaft extending coaxially through said annular stator structure; and the axially extending, cylindrical, permanent magnet shaft having a smooth external surface along a portion thereof with axially alternating N and S poles defined circumferentially in an outer periphery of the portion of the axially extending, cylindrical, permanent magnet shaft. The present invention also provides a method of magnetizing the shaft of such a motor and a fixture and method of manufacturing the fixture therefor.