← Back to Patent Explorer
US4349770A Expired / Lapsed US ⏱️ 0.0 years remaining

Electronic damping apparatus

Assignee: Xerox Corp
•
Filing: 1980-07-22
•
Granted: 1982-09-14
•
Expires: 2000-07-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Apparatus is disclosed for controlling the movement of a movable element to bring the movable element to rest at a desired stopping position. The apparatus comprises a multi-phase drive motor having a drive shaft coupled to the movable element for driving same, four electrically conductive coils mounted in position-displaced relationship about the shaft, and means coupled to the drive shaft and responsive to the selective energization of the coils by respective motor drive signals for causing the corresponding rotation of said drive shaft and movement of said movable element. A sensor is coupled to the drive shaft and is responsive to the rotation thereof for generating an electrical signal containing information indicative of the direction, speed and distance of movement of said movable element. Further, means are included for detecting from the distance information indicated by the electrical signal whether the movable element is within a predetermined distance of said desired stopping position. When it is, a controller controls the levels of the motor drive signals in dependence upon the direction information indicated by the electrical signal such that the motor and thus the movable element are brought to a final stop with only a single one of the motor drive signals and thus corresponding single motor coil on. The controller selectively turns on and off or reverses either the two coils displaced counterclockwise of the single motor coil about the shaft or the two coils displaced clockwise of the single motor coil about the shaft in dependence upon the direction information indicated by the electrical signal.

Inventors

  • 👤 Robert A. Ragen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 02:26
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/231; G05B19/232; B; B41; B41J; B41J1/00; B41J1/22; B41J1/24; G05B2219/00; G05B2219/30; G05B2219/34; G05B2219/34215; G05B2219/37; G05B2219/37313; G05B2219/41; G05B2219/41326; G05B2219/42; G05B2219/42182; G05B2219/43; G05B2219/43006; G05B2219/43181; G05B2219/43194

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 267 words
Apparatus for controlling the movement of a movable element to bring said movable element to rest at a desired stopping position, said apparatus comprising: a multi-phase drive motor having a drive shaft coupled to said movable element for driving same, four electrically conductive coils mounted in position-displaced relationship about said shaft, and means coupled to said drive shaft and responsive to the selective energization of said coils by respective motor drive signals for causing the corresponding rotation of said drive shaft and movement of said movable element; a sensor coupled to said drive shaft and responsive to the rotation thereof for generating an electrical signal containing information indicative of the direction, speed and distance of movement of said movable element; means for detecting from the distance information indicated by said electrical signal whether said movable element is within a predetermined distance of said desired stopping position; and control means for controlling the levels of said motor drive signals in dependence upon the direction information indicated by said electrical signal following detection of said movable element being within said predetermined distance of said desired stopping position, said motor and thus said movable element being brought to a final stop with only a single one of said motor drive signals and thus corresponding single motor coil on, said control means including means for selectively turning on and off or reversing either the two coils displaced counterclockwise of said single motor coil about said shaft or the two coils displaced clockwise of said single motor coil about said shaft in dependence upon the direction information indicated by said electrical signal.
Claim 2
Dependent Claim 267 words
Apparatus for controlling the movement of a movable element to bring said movable element to rest at a desired stopping position, said apparatus comprising: a multi-phase drive motor having a drive shaft coupled to said movable element for driving same, four electrically conductive coils mounted in position-displaced relationship about said shaft, and means coupled to said drive shaft and responsive to the selective energization of said coils by respective motor drive signals for causing the corresponding rotation of said drive shaft and movement of said movable element; a sensor coupled to said drive shaft and responsive to the rotation thereof for generating an electrical signal containing information indicative of the direction, speed and distance of movement of said movable element; means for detecting from the distance information indicated by said electrical signal whether said movable element is within a predetermined distance of said desired stopping position; and control means for controlling the levels of said motor drive signals in dependence upon the direction information indicated by said electrical signal following detection of said movable element being within said predetermined distance of said desired stopping position, said motor and thus said movable element being brought to a final stop with only a single one of said motor drive signals and thus corresponding single motor coil on, said control means including means for selectively turning on and off or reversing either the two coils displaced counterclockwise of said single motor coil about said shaft or the two coils displaced clockwise of said single motor coil about said shaft in dependence upon the direction information indicated by said electrical signal.
Claim 3
Dependent Claim 36 words
The apparatus of claim 1, wherein said single one motor drive signal and thus corresponding single motor coil is turned on by said control means following detection of said movable element being within said predetermined distance.
Claim 4
Dependent Claim 256 words
Apparatus for controlling the movement of a movable element to bring said movable element to rest at a desired stopping position, said apparatus comprising: a multi-phase drive motor having a drive shaft coupled to said movable element for driving same, four electrically conductive coils mounted in position-displaced relationship about said shaft, and means coupled to said drive shaft and responsive to the selective energization of said coils by respective motor drive signals for causing the corresponding rotation of said drive shaft and movement of said movable element; a sensor coupled to said drive shaft and responsive to the rotation thereof for generating an electrical signal containing information indicative of the direction, speed and distance of movement of said movable element; means for detecting from the distance information indicated by said electrical signal whether said movable element is within a predetermined distance of said desired stopping position; and control means for controlling the levels of said motor drive signals in dependence upon the direction information indicated by said electrical signal following detection of said movable element being within said predetermined distance of said desired stopping position, said motor and thus said movable element being brought to a final stop with two adjacent motor coils turned on by their respective motor drive signals, said control means including means for selectively turning on and off or reversing one of said two adjacent motor coils and a third motor coil adjacent the other of said two adjacent motor coils during movement of said movable element toward said desired stopping position.
Claim 5
Dependent Claim 256 words
Apparatus for controlling the movement of a movable element to bring said movable element to rest at a desired stopping position, said apparatus comprising: a multi-phase drive motor having a drive shaft coupled to said movable element for driving same, four electrically conductive coils mounted in position-displaced relationship about said shaft, and means coupled to said drive shaft and responsive to the selective energization of said coils by respective motor drive signals for causing the corresponding rotation of said drive shaft and movement of said movable element; a sensor coupled to said drive shaft and responsive to the rotation thereof for generating an electrical signal containing information indicative of the direction, speed and distance of movement of said movable element; means for detecting from the distance information indicated by said electrical signal whether said movable element is within a predetermined distance of said desired stopping position; and control means for controlling the levels of said motor drive signals in dependence upon the direction information indicated by said electrical signal following detection of said movable element being within said predetermined distance of said desired stopping position, said motor and thus said movable element being brought to a final stop with two adjacent motor coils turned on by their respective motor drive signals, said control means including means for selectively turning on and off or reversing one of said two adjacent motor coils and a third motor coil adjacent the other of said two adjacent motor coils during movement of said movable element toward said desired stopping position.
Claim 6
Dependent Claim 32 words
The apparatus of claim 3, wherein the other of said two adjacent motor coils is turned on by said control means following detection of said movable element being within said predetermined distance.
Claim 7
Dependent Claim 16 words
The apparatus of claim 2 or claim 4, wherein said drive motor is a stepper motor.
Claim 8
Dependent Claim 17 words
The apparatus of claim 5, wherein said stepper motor is a four-phase motor including said four coils.
Claim 9
Dependent Claim 63 words
The apparatus of claim 6, wherein, at a constant velocity of movement of said movable element, said electrical signal is periodic with a peak amplitude and frequency proportional to the velocity of said movable element, has a polarity indicative of the direction of movement of said movable element, and has a period representative of a predetermined increment of movement of said movable element.
Claim 10
Dependent Claim 107 words
The apparatus of claim 7, wherein said sensor comprises: an electrically conductive sensor coil mounted adjacent the drive shaft of said motor; flux producing means mounted adjacent said sensor coil for producing a path of normally substantially constant magnetic flux adjacent said coil; and flux varying means coupled to said drive shaft and responsive to the rotation of said drive shaft by said motor for varying the level of said magnetic flux adjacent said coil in dependence upon the direction, speed and distance of rotation of said drive shaft, whereby the resultant electromotive force induced in said sensor coil defines said electrical signal across said sensor coil.
Claim 11
Dependent Claim 22 words
The apparatus of claim 8, wherein said sensor comprises at least two sensor coils mounted adjacent the drive shaft of said motor.
Claim 12
Dependent Claim 25 words
The apparatus of claim 9, wherein said at least two sensor coils are aligned about said drive shaft with respective ones of said motor coils.
Claim 13
Dependent Claim 31 words
The apparatus of claim 10, wherein two of said electrical signals are respectively generated by said at least two sensor coils, said two electrical signals being mutually electrically phase-displaced by 90°.
Claim 14
Dependent Claim 14 words
The apparatus of claim 11, wherein said two electrical signals are substantially sinusoidal waveforms.
Claim 15
Dependent Claim 37 words
The apparatus of claim 1, further comprising: means coupled to said sensor coils for generating four square-wave signals; and means responsive to the levels of said square-wave signals for controlling the levels of said motor drive signals.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-09-13 1986-03-15 1986-09-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-09-13 1990-03-15 1990-09-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-09-13 1994-03-15 1994-09-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag