US4310841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal handling apparatus
Assignee: Schneider Electric Systems USA Inc
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Filing: 1978-07-10
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Granted: 1982-01-12
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Expires: 1998-07-10
Abstract
Abstract Signal-processing apparatus for use with industrial instrumentation systems and the like, and comprising a memory to maintain a signal level for long time periods without drift. An input signal level is translated into the positioning of a movable member, through the use of an actuator motor controlled by the input signal and a position feedback signal. A friction device is coupled to the movable member to hold it in any given position, thereby to serve as a memory for the input signal level. The friction device comprises a thin vane-like element which is secured to the movable member and disposed in the air-gap of a permanent magnet. The air-gap also includes a mass of tiny magnetizable particles which, under the influence of the magnetic field, engage the surfaces of the vane-like element to develop a frictional restraining force. This frictional restraint has the characteristic of being relatively low upon initial movement away from a start point, and thereafter increasing progressively to a plateau level, thereby providing superior dynamic performance particularly in a servo positioning system. Various applications are disclosed including process controllers and chart recorder systems.
Inventors
- 👤 Everett O. Olsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:32
CPC Classifications
G; G05; G05B; G05B7/00; G05B7/02; G01; G01D; G01D11/00; G01D11/16; G01R; G01R1/00; G01R1/02; G01R1/14; G01R13/00; G01R13/04; G01R17/00; G01R17/02; G01R17/06
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
282 words
Manually-operated signal-controlling apparatus with memory means for retaining a signal level at a fixed (constant) value during times intervening changes in input magnitude, said apparatus comprising, in combination: a member mounted for movement within a predetermined range by the application of a relatively light force; actuator means forming an operative part of said movable member and including manually-operable means adapted to be grasped manually to permit the position of said member readily to be changed to any desired location with said range; magnetic friction means coupled to said movable member to hold said member securely in position in the absence of a manually-applied force tending to shift its position, said magnetic friction means including a mass of small magnetized particles frictionally engaged with said member for continuously corresponding movement therewith to develop said friction force by surface contact between said member and the particles, said particles being supported to provide for movement relative to one another and also to accommodate movement of said member relative to said particles, said magnetic friction means serving to restrain the movement of said member with a force sufficient to hold said member firmly in position in the absence of said manually-applied force while permitting relatively easy manual changes in position of said member, with only light manual force required; and position read-out means coupled to said movable member, said read-out means comprising sensing means in the form of a transducing device responsive to the positioning of said member within said predetermined range to produce for a remote utilization device a transmittable position signal having an energy-level characteristic the magnitude of which corresponds to the position of said member held in place by said magnetic friction means.
Claim 2
Dependent Claim
282 words
Manually-operated signal-controlling apparatus with memory means for retaining a signal level at a fixed (constant) value during times intervening changes in input magnitude, said apparatus comprising, in combination: a member mounted for movement within a predetermined range by the application of a relatively light force; actuator means forming an operative part of said movable member and including manually-operable means adapted to be grasped manually to permit the position of said member readily to be changed to any desired location with said range; magnetic friction means coupled to said movable member to hold said member securely in position in the absence of a manually-applied force tending to shift its position, said magnetic friction means including a mass of small magnetized particles frictionally engaged with said member for continuously corresponding movement therewith to develop said friction force by surface contact between said member and the particles, said particles being supported to provide for movement relative to one another and also to accommodate movement of said member relative to said particles, said magnetic friction means serving to restrain the movement of said member with a force sufficient to hold said member firmly in position in the absence of said manually-applied force while permitting relatively easy manual changes in position of said member, with only light manual force required; and position read-out means coupled to said movable member, said read-out means comprising sensing means in the form of a transducing device responsive to the positioning of said member within said predetermined range to produce for a remote utilization device a transmittable position signal having an energy-level characteristic the magnitude of which corresponds to the position of said member held in place by said magnetic friction means.
Claim 3
Dependent Claim
34 words
Apparatus as claimed in claim 1, wherein said read-out means comprises means coupled non-mechanically to said movable member, whereby to produce said position signal without additional friction effects on the movement of said member.
Claim 4
Dependent Claim
25 words
Apparatus as claimed in claim 1, wherein said read-out means comprises means to produce an electrical signal proportional to the position of said movable member.
Claim 5
Dependent Claim
59 words
Apparatus as claimed in claim 3, wherein said read-out means comprises a Hall-effect crystal mounted with said member for movement in a magnetic field, said magnetic field serving to control the output signal level produced by said crystal as a function of the position of said crystal, and thereby as a function of the position of said movable member.
Claim 6
Dependent Claim
42 words
Apparatus as claimed in claim 1, wherein said actuator means further comprises force-producing means responsive to an input signal for applying to said member a reversible force of sufficient strength to move said member against the restraint of said magnetic friction means.
Claim 7
Dependent Claim
14 words
Apparatus as claimed in claim 5, wherein said actuator means comprises an electrical motor.
Claim 8
Dependent Claim
15 words
Apparatus as claimed in claim 6, wherein said motor is of the moving coil type.
Claim 9
Dependent Claim
34 words
Apparatus as claimed in claim 1, including a utilization device responsive to said position signal for controlling the position of an operating element; and means for transmitting said position signal to said utilization device.
Claim 10
Dependent Claim
66 words
Apparatus as claimed in claim 8, wherein said actuator means further comprises signal-responsive force-producing means for applying a moving force to said member; said utilization device comprising a valve operator responsive to said position signal for correspondingly determining the position of a process valve, whereby said manually-operable means serves as a position-controlling element for the valve in the absence of motor-controlled actuation of said movable member.
Claim 11
Dependent Claim
41 words
Apparatus as claimed in claim 9, inluding a control-function-generator for producing a control signal for said force-producing means; said magnetic friction means providing for bumpless-balanceless transfer to manual operation when said control-function-generator is disconnected from operative control of said force-producing means.
Claim 12
Dependent Claim
41 words
Apparatus as claimed in claim 1, wherein said read-out means comprises an indicator arranged for movement with said movable member; and means associated with indicator to provide a visually-intelligible representation of the signal level corresponding to the positioning of said member.
Claim 13
Dependent Claim
20 words
Apparatus as claimed in claim 11, wherein said associated means comprises a marked scale having symbols cooperating with said indicator.
Claim 14
Dependent Claim
161 words
Process control apparatus comprising: control-function-generator means to produce a control signal responsive to a measured condition; a movable member; actuator means responsive to said control signal for applying a force to said member to move it to positions corresponding to said control signal; friction means comprising a mass of small magnetizable particles for developing a restraining force to hold said member in position in the absence of a force from said actuator means, said magnetized particles engaging an element integral with or coupled to said movable member an arranged for continuously corresponding movement therewith to develop said friction force by surface contact between said element and the particles, said particles being supported to provide for movement relative to one another and also to accommodate movement of said element relative to said particles; and read-out means responsive to the positioning of said movable member for developing an output signal transmittable to a remote location for controlling a valve operator or the like.
Claim 15
Dependent Claim
161 words
Process control apparatus comprising: control-function-generator means to produce a control signal responsive to a measured condition; a movable member; actuator means responsive to said control signal for applying a force to said member to move it to positions corresponding to said control signal; friction means comprising a mass of small magnetizable particles for developing a restraining force to hold said member in position in the absence of a force from said actuator means, said magnetized particles engaging an element integral with or coupled to said movable member an arranged for continuously corresponding movement therewith to develop said friction force by surface contact between said element and the particles, said particles being supported to provide for movement relative to one another and also to accommodate movement of said element relative to said particles; and read-out means responsive to the positioning of said movable member for developing an output signal transmittable to a remote location for controlling a valve operator or the like.
Claim 16
Dependent Claim
27 words
Apparatus as claimed in claim 13, wherein said read-out means comprises a transducer adapted to develop an output electrical signal proportional to the position of said member.
Claim 17
Dependent Claim
16 words
Apparatus as claimed in claim 14, wherein said transducer produces a D.C. voltage proportional to position.
Claim 18
Dependent Claim
37 words
Apparatus as claimed in claim 13, including feedback means responsive to the output of said read-out means and arranged to direct a feedback signal to the input of said actuator means in opposition to said control signal.
Claim 19
Dependent Claim
27 words
Apparatus as claimed in claim 16, wherein said feedback means directs to said actuator means a feedback signal which corresponds directly to the position of said member.
Claim 20
Dependent Claim
35 words
Apparatus as claimed in claim 13, wherein said control-function-generator means comprises feedback means responsive to the position of said member for directing a feedback signal to said actuator means as part of said control signal.
Claim 21
Dependent Claim
43 words
Apparatus as claimed in claim 18, including means to develop an electrical signal corresponding to the position of said member. said feedback means including capacitive means coupling said electrical signal to said actuator means to provide reset action in the controlling output signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-01-11 | 1985-07-13 | 1986-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-11 | 1989-07-13 | 1990-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-11 | 1993-07-13 | 1994-01-12 | $7700.00 | Window Closed / Lapsed |