Patent US4170902A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4100480A Expired / Lapsed US ⏱️ 0.0 years remaining

Position and velocity sensors

Assignee: Ricoh Printing Systems America Inc
•
Filing: 1976-08-20
•
Granted: 1978-07-11
•
Expires: 1996-08-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A sensor of the linear voltage differential transformer (LVDT) type is described, with a moveable core, which has both high permeability and magnetic retentivity, to thereby provide both position and velocity signals. Also described are various embodiments of a position sensor which provides a position signal of the same amplitude, example a null, whenever the sensor's core is at any one of controllable selected positions within the sensor. Any of these sensors may include a core with magnetic retentivity to provide a velocity signal. A servo control system is disclosed, utilizing the position signals from one of the sensors, as described, to control the positioning of an element at either of two positions.

Inventors

  • 👤 Dan R. Lytle
  • 👤 Ronald C. Burski

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 23:11
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/20; G01D5/22; G01D5/225; G01D5/2258; G01D5/2266; G01D5/2291; G01P; G01P3/00; G01P3/42; G01P3/50; G01P3/52

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 145 words
In a position sensor including a primary winding to which an AC signal is appliable, first and second secondary windings, a moveable core coupling said primary winding to said secondary windings, and connecting means for connecting said secondary windings so that AC signals induced therein as a function of the AC signal in said primary winding are 180° out of phase with respect to one another, the sensor providing an output signal whose amplitude is a function of the core position with respect to said secondary windings, the improvement comprising: controllable means included in said connecting means for controlling the connections between the secondary windings to cause said sensor to provide an output signal of a same selected amplitude when said core is at any one of n different positions with respect to said secondary windings, where n is an integer not less than 2.
Claim 2
Dependent Claim 145 words
In a position sensor including a primary winding to which an AC signal is appliable, first and second secondary windings, a moveable core coupling said primary winding to said secondary windings, and connecting means for connecting said secondary windings so that AC signals induced therein as a function of the AC signal in said primary winding are 180° out of phase with respect to one another, the sensor providing an output signal whose amplitude is a function of the core position with respect to said secondary windings, the improvement comprising: controllable means included in said connecting means for controlling the connections between the secondary windings to cause said sensor to provide an output signal of a same selected amplitude when said core is at any one of n different positions with respect to said secondary windings, where n is an integer not less than 2.
Claim 3
Dependent Claim 52 words
The improvement as described in claim 1 wherein each of said secondary windings includes a plurality of turns and said controllable means include switchable means for controlling the number of turns of each of said secondary windings which are serially connected to be in any one of n selected combinations of connections.
Claim 4
Dependent Claim 41 words
The improvement as described in claim 1 wherein said controllable means include resistive means and switchable means for controlling the connections between said secondary windings to be in any one of n selected different combinations of connections through said resistive means.
Claim 5
Dependent Claim 82 words
The improvement as described in claim 1 wherein each of said secondary windings consists of a plurality of turns and said controllable means include separate resistive means connected across selected number of turns of each of said secondary windings, and switch means for controlling the connections between each secondary winding and the resistive means connected to the other secondary winding to control said output signal to be of said selected amplitude when said core is at any of said n selected positions.
Claim 6
Dependent Claim 17 words
The improvement as described in claim 4 wherein the selected amplitude of said output signal is zero.
Claim 7
Dependent Claim 50 words
The improvement as described in claim 4 wherein the resistive means connected across the first of said secondary windings includes at least one variable resistor with a selectively moveable arm, and said switch means includes a switch for selectively connecting said moveable arm to the second of said secondary windings.
Claim 8
Dependent Claim 77 words
The improvement as described in claim 1 wherein said controllable means include first and second resistive means respectively connected across selected numbers of turns of said first and second secondary windings, each of said resistive means including a variable resistor with a moveable arm, said controllable means including first and second switches for selectively connecting the moveable arms of the variable resistors of said first and second resistive means to said second and first secondary windings, respectively.
Claim 9
Dependent Claim 59 words
The improvement as described in claim 1 wherein n=2 and said controllable means include first and second variable resistors respectively connected across selected numbers of turns of said first and second secondary windings, and first and second switches for selectively connecting the moveable arms of said first and second variable resistors to said second and first secondary windings, respectively.
Claim 10
Dependent Claim 192 words
In a sensor comprising a primary winding to which AC drive signals are appliable, a pair of secondary windings and a moveable core of the type having relatively high permeability properties for coupling signals corresponding to said AC drive signals into said secondary windings, means for interconnecting said secondary windings so that AC signals coupled therein by the core in response to the drive signals are 180° out of phase with respect to one another, with the sensor providing a position signal whose amplitude is a function of the core position with respect to said secondary windings, and further including controllable means coupled to said secondary windings for controlling the connections therebetween to cause said position signal to be of a same selected amplitude when said core is at any one of n different positions with respect to said secondary windings, where n is an integer not less than 2, the improvement comprising: said core having magnetic retentivity, whereby as said core moves with respect to said secondary windings it induces a DC signal in said secondary windings, the DC signal amplitude being related to the rate of movement of said core.
Claim 11
Dependent Claim 192 words
In a sensor comprising a primary winding to which AC drive signals are appliable, a pair of secondary windings and a moveable core of the type having relatively high permeability properties for coupling signals corresponding to said AC drive signals into said secondary windings, means for interconnecting said secondary windings so that AC signals coupled therein by the core in response to the drive signals are 180° out of phase with respect to one another, with the sensor providing a position signal whose amplitude is a function of the core position with respect to said secondary windings, and further including controllable means coupled to said secondary windings for controlling the connections therebetween to cause said position signal to be of a same selected amplitude when said core is at any one of n different positions with respect to said secondary windings, where n is an integer not less than 2, the improvement comprising: said core having magnetic retentivity, whereby as said core moves with respect to said secondary windings it induces a DC signal in said secondary windings, the DC signal amplitude being related to the rate of movement of said core.
Claim 12
Dependent Claim 30 words
The improvement as described in claim 9 wherein said core is of preselected dimension and is formed of a hardened mixture of matter exhibiting relatively high permeability and magnetic retentivity.
Claim 13
Dependent Claim 48 words
The improvement as described in claim 9 wherein said core comprises an elongated magnetic member of preselected cross section in a direction transverse to its length and matter of relatively high permeability fixedly connected to at least a portion of the outer surface of said elongated magnetic member.
Claim 14
Dependent Claim 29 words
The improvement as described in claim 11 wherein said relatively high permeability matter extends outwardly from said magnetic member about most of its length except near its opposite ends.
Claim 15
Dependent Claim 52 words
The improvement as described in claim 9 wherein each of said secondary windings includes a plurality of turns and said controllable means include switchable means for controlling the number of turns of each of said secondary windings which are serially connected to be in any one of n selected combinations of connections.
Claim 16
Dependent Claim 41 words
The improvement as described in claim 9 wherein said controllable means include resistive means and switchable means for controlling the connections between said secondary windings to be in any one of n selected different combinations of connections through said resistive means.
Claim 17
Dependent Claim 82 words
The improvement as described in claim 9 wherein each of said secondary windings consists of a plurality of turns and said controllable means include separate resistive means connected across selected number of turns of each of said secondary windings, and switch means for controlling the connections between each secondary winding and the resistive means connected to the other secondary winding to cause said position signal to be of said selected amplitude when said core is at any of said n selected position.
Claim 18
Dependent Claim 46 words
The improvement as described in claim 15 wherein the resistive means connected across the first secondary winding includes at least one variable resistor with a selectively moveable arm, and said switch means includes a switch for selectively connecting said moveable arm to the second secondary winding.
Claim 19
Dependent Claim 17 words
The improvement as described in claim 15 wherein the selected amplitude of said position signal is zero.
Claim 20
Dependent Claim 77 words
The improvement as described in claim 9 wherein said controllable means include first and second resistive means respectively connected across selected numbers of turns of said first and second secondary windings, each of said resistive means including a variable resistor with a moveable arm, said controllable means including first and second switches for selectively connecting the moveable arms of the variable resistors of said first and second resistive means to said second and first secondary windings, respectively.
Claim 21
Dependent Claim 59 words
The improvement as described in claim 9 wherein n=2 and said controllable means include first and second variable resistors respectively connected across selected numbers of turns of said first and second secondary windings, and first and second switches for selectively connecting the moveable arms of said first and second variable resistors to said second and first secondary windings, respectively.
Claim 22
Dependent Claim 186 words
A hammer bank system useful in an impact printer of the type including a printer control section for controlling the printer operation, the hammer bank system comprising: a moveable hammer bank; drive means coupled to said hammer bank for driving the hammer bank to be at any one of n positions where n is an integer not less than 2; and control means responsive to a command signal for controlling said drive means to drive said hammer bank from one of said n positions to another, said control means including a sensor coupled to said hammer bank, said sensor including a primary winding to which AC drive signals are appliable, first and second secondary windings, a moveable core, and controllable means for controlling the connections between said secondary windings so that AC signals induced therein as a function of the AC drive signals in said primary winding are 180° out of phase with respect to one another, and for providing a position signal which is of a same selected amplitude when said core is at any of said n positions with respect to said secondary windings.
Claim 23
Dependent Claim 186 words
A hammer bank system useful in an impact printer of the type including a printer control section for controlling the printer operation, the hammer bank system comprising: a moveable hammer bank; drive means coupled to said hammer bank for driving the hammer bank to be at any one of n positions where n is an integer not less than 2; and control means responsive to a command signal for controlling said drive means to drive said hammer bank from one of said n positions to another, said control means including a sensor coupled to said hammer bank, said sensor including a primary winding to which AC drive signals are appliable, first and second secondary windings, a moveable core, and controllable means for controlling the connections between said secondary windings so that AC signals induced therein as a function of the AC drive signals in said primary winding are 180° out of phase with respect to one another, and for providing a position signal which is of a same selected amplitude when said core is at any of said n positions with respect to said secondary windings.
Claim 24
Dependent Claim 35 words
The system as described in claim 20 wherein said control means include movement rate control means for controlling the rate of movement of said hammer bank by said drive means between any of said positions.
Claim 25
Dependent Claim 41 words
The system as described in claim 20 wherein said controllable means include resistive means and switchable means for controlling the connections between said secondary windings to be in any one of n selected different combinations of connections through said resistive means.
Claim 26
Dependent Claim 47 words
The system as described in claim 20 wherein said core has relatively high permeability properties and further has magnetic retentivity, to thereby induce a DC signal in said secondary windings which is related to the rate of movement of said core with respect to said secondary windings.
Claim 27
Dependent Claim 82 words
The system as described in claim 20 wherein each of said secondary windings consists of a plurality of turns and said controllable means include separate resistive means connected across selected number of turns of each of said secondary windings, and switch means for controlling the connections between each secondary winding and the resistive means connected to the other secondary winding to control said output signal to be of said selected amplitutde when said core is at any of said n selected positions.
Claim 28
Dependent Claim 17 words
The system as described in claim 24 wherein the selected amplitude of said output signal is zero.
Claim 29
Dependent Claim 47 words
The system as described in claim 24 wherein said core has relatively high permeability properties and further has magnetic retentivity, to thereby induce a DC signal in said secondary windings which is related to the rate of movement of said core with respect to said secondary windings.
Claim 30
Dependent Claim 17 words
The system as described in claim 26 wherein the selected amplitude of said output signal is zero.
Claim 31
Dependent Claim 50 words
The system as described in claim 26 wherein the resistive means connected across the first of said secondary windings includes at least one variable resistor with a selectively moveable arm, and said switch means includes a switch for selectively connecting said moveable arm to the second of said secondary windings.
Claim 32
Dependent Claim 59 words
The system as described in claim 28 wherein n=2 and said controllable means include first and second variable resistors respectively connected across selected numbers of turns of said first and second secondary windings, and first and second switches for selectviely connecting the moveable arms of said first and second variable resistors to said second and first secondary windings, respectively.
Claim 33
Dependent Claim 17 words
The system as described in claim 29 wherein the selected amplitude of said output signal is zero.
Claim 34
Dependent Claim 43 words
The system as described in claim 21 wherein said movement rate control means include means for controlling the hammer bank to move from one of said positions to another at rates which vary from a selected high rate to a selected low rate.

References Cited (Backward Citations)

US2555853A Cited
US2764019A Cited
US3085191A Cited
US3225289A Cited
US3244956A Cited
US3943443A Cited
US3911814A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-07-10 1982-01-09 1982-07-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-07-10 1986-01-09 1986-07-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-07-10 1990-01-09 1990-07-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag