US3741357A - Position controlling system - Google Patents
Position controlling system Download PDFInfo
- Publication number
- US3741357A US3741357A US00197716A US3741357DA US3741357A US 3741357 A US3741357 A US 3741357A US 00197716 A US00197716 A US 00197716A US 3741357D A US3741357D A US 3741357DA US 3741357 A US3741357 A US 3741357A
- Authority
- US
- United States
- Prior art keywords
- brake
- document
- clutch
- paper
- controlling system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K13/00—Conveying record carriers from one station to another, e.g. from stack to punching mechanism
- G06K13/02—Conveying record carriers from one station to another, e.g. from stack to punching mechanism the record carrier having longitudinal dimension comparable with transverse dimension, e.g. punched card
- G06K13/06—Guiding cards; Checking correct operation of card-conveying mechanisms
- G06K13/067—Checking presence, absence, correct position, or moving status of cards
Definitions
- ABSTRACT A serial loop memory, such as a ring counter, for example, of capacity equal to the units of distance between a sensing station and a desired stopping station is operated in synchronism with a transport mechanism whenever an article in the transport system has been sensed and has not yet stopped.
- the complement in the loop memory is used as a feed-forward correction to modify the application of braking means to the transport system so that the brake application will take place at an appropriate time during the next document cycle.
- a simpler method would be to provide a sensor a certain distance ahead of the desired stop position and then to declutch the document transport or transport section that needs to be stopped and apply a brake in response to the passage of adocument past the sensor.
- Such arrangement does not assure accurate stopping, however, because even with good brakes, for example, such as a magnetic'particle clutch engaging a stationary shaft, the characteristics will change with time and temperature. Hence, there is a gradual drift in the stopping position of the document. From cycle to cycle of the transport operation, however, the operation would be quite consistent, that is, within the range of randomness of the brake itself.
- a more particular object of the present invention is to provide a position control system which is relatively inexpensive compared to the more complex closedloop feedback-control systems previously utilized for this purpose.
- Still another object of the present invention is to provide a positioning control system for a document transport in which thedocuments can be halted with a high degree of precision on each operating cycle.
- a pulse generator which generates an output pulse for each selected unit of transport travel, such units preferably being quite small, for example, in the order of 0.01 inch.
- These pulses are selected so as to be able to actuate a serial loop memory device, which in turn actuates the brake mechanism.
- a ring counter is used as the serial loop memory device and the supply of pulses from the document-transport generator is disabled after a document comes to a stop, and is then activated again by the leading edge of the next document passing a suitable sensing mechanism located some distance ahead of the stopping point, this distance being somewhat in excess of the braking distance.
- the nominal distance between the sensor and the stopping position is always equal to the product of the counts in the ring counter and the unit of transport travel for a single pulse. It is obvious that the distance thus determined must exceed any maximum braking distance under the least favorable conditions so that there is always a positive distance between the sensing device, which senses the leading edge of the oncoming document, and the point of brake application.
- the brake is always applied when the counter reaches a certain count which, for convenience, may be the zero point since it is relatively easy to detect, but other points in the counter operation could be utilized.
- the counter advances from the zero position by as many positions as the document advances units of travel during its braking path. Then after the next document passes the sensor, the counter advances further and when it comes again to the zero point, the brake is applied.
- the distance between the sensor and the point of brake application then becomes the nominal distance between the sensor and the stopping position minus the braking distance of the previous cycle.
- combinations of pulse generators and suitable counters operated thereby may be utilized by co-acting document transport systems for merging of different items, for example, merging a web of paper to a film web.
- FIG. 1 of the drawings there is shown in schematic form a document transport system which comprises a first embodiment of the present in vention.
- a motor 3 which is in continuous operation, is arranged to selectively drive a feed roll or pulley 5 via a clutch 7 and a brake 9 arranged as shown.
- these elements are conventional, and it will be understood that when a suitable supply of energy to clutch 7 is enabled, the drum or drive pulley 5 will be rotated in the direction indicated by the arrow, and when clutch 7 is released and brake 9 is applied by the supply thereto of control signals, the drum or drive pulley 5 will be abruptly stopped.
- An endless transport belt 11 rides over the drive pulley or drum 5 and over a second pulley or drum 13, which may be considered as an idler.
- An emitter or pulse generator 15 is connected to the shaft of the pulley or drum l3, and this pulse generator may take any one of a number of forms, such as a magnetic or photoelectric device, the only requirement being that it supply a series of discrete pulses or signals during the rotation of the pulley or drum 13.
- the parts are selected and arranged so that for every predetermined unit of travel of the belt, for example, 0.02 inch, a pulse is emitted.
- the desired stopping location for documents 17 moving on this belt is indicated by the dotted line designated as SP.
- a document sensor device 19 which may be any one of a number of suitable devices such as a photo-electric cell or other device, which will cause an output signal to be generated when the leading edge of the document 17 passes the location of the document sensor 19.
- Trigger 21 is turned on by a pulse from a document sensor 19 and reset to its off condition by the output of a single shot 23, the input of which is connected to the output of emitter 15. Emitter 15 also supplies signals to the input of an AND circuit 25, the other input of AND circuit 25 being connected to the output of trigger 21, which is enabled when the trigger is on.
- the output of AND circuit 25 is supplied as an input to a counter 27, the output of which is supplied as an input to clutch and brake control circuits 29, which control the clutch 7 and brake 9.
- Counter 27 is a ring-type counter, that is, one of the well-known type in which pulses cause the counter stages to successively count and to repeat after a certain maximum count is reached.
- the maximum count which counter 27 can attain is determined by the distance between the document sensor 19 and the stopping point SP. This distance, divided by the number of unit distances equivalent to the output of the emitter or generator 15 represents the number of counts which the counter 27 can contain. For example, if the transport travel is 0.02 inches per emitter pulse, and the document sensor is located 2.56 inches to the rear of the stopping point SP, then it will be apparent that a 128 position ring counter would be used for counter 27.
- the document travel will correspond to a value n-X1 emitter pulses before brake ap plication and to X1 emitter pulses during braking.
- the total document travel between the reference point and the stopping position now becomes n, that is, the document comes to rest exactly at the desired location.
- the brake behavior is not exactly the same in the second cycle as it was in the first, the number of emitter pulses over the braking distance of the second cycle, which may be represented by the value X2, would differ slightly from X1, and X2-Xl would represent the number of emitter pulses corresponding to the error in positioning.
- This system requires deactivation of counter 27 between the time a document comes to rest at the stopping point SP, and the leading edge of the next document passes the reference point designated by the sensor 19.
- deactivation is achieved in the present instance by inhibiting the supply of signals from the emitter 15 to the memory means or counter 27, by; the single shot 23, which is timed in such manner that when the intervals between the emitter pulses become greater than a predetermined value, as will result from stopping of the transport by the brake 9, then single shot 23 will provide an output pulse to reset trigger 21, which will in turn disable the AND circuit 25 so that not further counts are supplied from source 15 to counter 27.
- the counter 27 could also be deactivated by means not shown, from the signal supplied to clutch 7, which will carry the document 17 forward from the stopping point SP after whatever operation is to be performed on the document at that point has been accomplished. In either case, the counter is activated again by the signal from sensor 19 that the next document is passing that point.
- FIG. 2 of the drawings is a table illustrating the operation of the system shown in FIG. 1 under various operating conditions for the brake. It is assumed, for the purposes of the illustration shown in this table, that the document sensor is located 2.56 inches ahead of the stopping point, and with an emitter pulse delivered for each 0.02 inch travel of the transport, it will be apparent, as previously pointed out, that the counter would have 128 positions.
- a dummy document when the count is lost due to power off or in the initial start-up of the transport, use may be made of artificial count injection by supplying to the counter a count of 90 pulses upon start up, when power-on conditions occur.
- the ring counter should be comprised of non-volatile storage elements, such as magnetic cores, even the first document will be positioned nearly correctly since the ring counter would be at about position 90 at the moment of start up, as it was reading when the machine was shut down after the last document had passed through.
- FIGS. 3 and 4 illustrate elaborations of the arrangement shown in FIG. 1 and described hereinbefore, these latter arrangements providing'a controlled merging of film and paper strips when a printing process on the paper has been briefly'interrupted by stopping the paper while the film keeps running.
- the basic problem is that of matching a predetermined line on the paper with a predetermined line on the film, with the paper starting from rest and the film moving continuously.
- the arrangement shown in FIG. 3 is a relatively simple arrangement which corrects for deviations in braking and accelerating distances of the previous cycle.
- the arrangement shown in FIG. 4 is somewhat more elaborate but has the advantage that it corrects for the accelerating distance of the previous cycle and the braking distance of the current cycle; in other words, even short term deviations in the braking distance are fully compensated.
- FIG. 3 utilizes two film sensors
- FIG. 4 shows only one film sensor and an additional ring counter.
- the second film sensor of FIG. 3 is fully interchangeable with an additional counter.
- One or the other is needed to compare film and paper positions at the merger point or any point nearby providing that at this point, the clutch is fully engaged even under worstcase conditions.
- FIG. 3 it will be seen that the upper portion of the arrangement shown therein, is similar to that previously described in connection with FIG. 1, in that a suitable clutch-and-brake paper transport is provided with an emitter 15 which sends discrete pulses to a ring counter 27 after being enabled by the passage of the paper past a paper sensor 19 and in the presence of a paper stop signal from a master control unit, not shown.
- the paper-transport brake-control 29 becomes operative to take the clutch off and set the brake on, thereby stopping the paper.
- Film sensor 2 is utilized to provide the disabling signal to the ring counter 27, the output signal of which actuates the paper-transport brake-control.
- the paper and film transports are, of course, suitably mechanically synchronized to perform the proper merging of the film and paper webs.
- the objective is to register the sum of the braking distance and the acceleration distance of the previous cycle on the count in the ring counter. Then when the Stop Paper command is supplied, brake action is delayed for the number of pulses from the papertransport emitter required to fill the counter. In other words, the further the paper travels during acceleration and deceleration in the previous cycle, the sooner the brake is applied.
- the second film sensor is used as an arbitrary reference point merely to establish the end of the acceleration period. It must be in the area where paper and film travel in unison, but it need not necessarily be at the theoretical merging point.v
- n as a subscript designates the nth cycle, we have l in-i and n il-t p N8 constant, i.e. proper merger is obtained. It is seen that for consistent performance of clutch and brake, the paper travels the distance N6 during the time the film advances from Sensor 1 to Sensor 2 irrespective of the particular characteristics of clutch and brake.
- FIG. 4 again has a large portion thereof similar to the arrangement shown in FIGS. 1 and 3 except that now the film transport is provided with an appropriate emitter as well as the paper transport, and there are additional counters as previously pointed out.
- the paper now accelerates and paper travel pulses are recorded starting from zero on ring counter 2 (45) via the paper emitter and the pulse gate 2 (39). Film travel pulses from the film emitter are counted starting with zero inring counter 1 (27a).
- counter 1 When counter 1 is filled, it indicates that paper acceleration is complete or slightly more than complete and the following action takes place: The output from ring counter 1 causes pulse gates l (37), 2 (39), and 5 (47) to become disabled. The machine will now operate normally, with counter 2 showing the acceleration distance of the paper, with counters 1 and 3 at zero.
- the machine continues to operate now until a signal from the master control gives a stop paper command, and a reference point on the paper reaches the paper sensor. At this time a signal will be passed by AND gate 49 causing the clutch to disengage and the brake to engage; the output of AND gate 49 also enables pulse gate 2 (39). At this time the paper transport emitter will add deceleration pulses to counter 2 (45) via pulse gate 2 (39). When the paper comes to rest, the reading on counter 2 (45) represents the sum of the acceleration pulses of the previous cycle and the deceleration pulses of the current cycle.
- counter 3 shows a complement of the sum of acceleration and deceleration pulses previously recorded on the counter 2, counters 2 and 3 being of equal capacity. At this time the paper is stationary and the film keeps moving. There is no change in the counter readlngs.
- this invention provides an improved method of accurately controlling the stopping distance of a movable mechanism, particularly a document transport system.
- the invention is applicable to multiple-operated devices, as long as they can be mechanically synchronized.
- a position controlling system for accurately positioning movable mechanical means comprising, in combination,
- a movable device to be operated in successive units of distance of substantially equal values
- power means for operating said device
- clutch means interposed between said device and said power means effective when energized to couple said device-to said power means to thereby move said device through a plurality of successive units
- brake means interposed between said clutch means and said device, effective when energized to stop the motion of said device
- serial loop memory means having an output connected to said brake or clutch control means and having a capacity equal to the number of said units betweena first sensing location and a stopping location for said device, a source of signals representative of said units, sensing means at said sensing location for initiating the entry of signals representing said units from said source to said memory means, and
- said memory means supplying an output to said control means when a predetermined count is reached in said memory means.
- sensing means comprises means for sensing the passage of a document at said sensing location.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Controlling Sheets Or Webs (AREA)
- Registering Or Overturning Sheets (AREA)
- Paper Feeding For Electrophotography (AREA)
- Exposure Or Original Feeding In Electrophotography (AREA)
- Conveying Record Carriers (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US19771671A | 1971-11-11 | 1971-11-11 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3741357A true US3741357A (en) | 1973-06-26 |
Family
ID=22730467
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00197716A Expired - Lifetime US3741357A (en) | 1971-11-11 | 1971-11-11 | Position controlling system |
Country Status (7)
Country | Link |
---|---|
US (1) | US3741357A (de) |
JP (1) | JPS5242981B2 (de) |
CA (1) | CA974628A (de) |
DE (1) | DE2247632C2 (de) |
FR (1) | FR2159893A5 (de) |
GB (1) | GB1368524A (de) |
IT (1) | IT967745B (de) |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3880421A (en) * | 1972-05-08 | 1975-04-29 | Grapha Holding Ag | Method and arrangement for handling streams of sheet goods |
US4440387A (en) * | 1977-04-08 | 1984-04-03 | Ricoh Company, Ltd. | Sheet feed apparatus |
US4455018A (en) * | 1981-05-11 | 1984-06-19 | International Business Machines Corporation | Document feeder electronic registration gate |
US4519700A (en) * | 1983-12-28 | 1985-05-28 | International Business Machines Corporation | Electronically gated paper aligner system |
US4538717A (en) * | 1982-02-16 | 1985-09-03 | Danfoss A/S | Control apparatus for a step drive |
US4610533A (en) * | 1981-01-20 | 1986-09-09 | Canon Kabushiki Kaisha | Automatic document feeding device |
US4613125A (en) * | 1983-01-20 | 1986-09-23 | Heidelberger Druckmaschinen Ag | Method and device for feeding sheets in register in a sheet-processing machine |
US4653008A (en) * | 1984-06-21 | 1987-03-24 | Iwatsu Electric Co., Ltd. | Method of controlling platemaking positions and errors |
US4657236A (en) * | 1984-07-20 | 1987-04-14 | Mitsubishi Jukogyo Kabushiki Kaisha | Sheet delivery device |
US4865309A (en) * | 1988-08-04 | 1989-09-12 | Cluett, Peabody & Co., Inc. | Method and apparatus for aligning workpieces of variable lengths |
US4877234A (en) * | 1988-08-02 | 1989-10-31 | Xerox Corporation | Sheet turning and registration system |
US5050858A (en) * | 1989-01-09 | 1991-09-24 | Alps Electric Co., Ltd. | Sheet feed control method |
US5480131A (en) * | 1982-01-25 | 1996-01-02 | Canon Kabushiki Kaisha | Paper feeding device |
US5538118A (en) * | 1994-10-19 | 1996-07-23 | Reell Precision Manufacturing Corporation | Electro-mechanical indexing clutch & method |
US5620077A (en) * | 1994-06-01 | 1997-04-15 | Electric Vehicle Controllers Ltd. | Fail-safe brake actuation system |
US6176483B1 (en) * | 1997-03-12 | 2001-01-23 | Bell & Howell Mail And Messaging Technologies Company | High speed document separator and sequencing apparatus |
US11117737B2 (en) | 2012-11-12 | 2021-09-14 | Southwire Company, Llc | Wire and cable package |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2829474C2 (de) * | 1978-07-05 | 1986-07-10 | Ruhrkohle Ag, 4300 Essen | Sicherheitseinrichtung für Gurtbänder mit Produkten- und Personenbeförderung |
DE3114073C2 (de) * | 1981-04-08 | 1984-05-10 | Alfred 5940 Lennestadt Tüschen | Bremseinrichtung für eine Förderanlage |
JPH04257875A (ja) * | 1991-02-12 | 1992-09-14 | Fuji Xerox Co Ltd | 自動原稿搬送装置 |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2853900A (en) * | 1953-12-17 | 1958-09-30 | Hillyer Instr Company | Automatic precision control device |
GB803268A (en) * | 1956-07-17 | 1958-10-22 | Francis Henry Shepard Jr | Intermittent drive apparatus |
US2874343A (en) * | 1953-08-25 | 1959-02-17 | Floyd G Steele | Digital servo |
US3224690A (en) * | 1963-04-15 | 1965-12-21 | Rudolph G Holman | Machine for winding a ball |
US3277355A (en) * | 1963-12-23 | 1966-10-04 | Gen Electric | Terminal condition predictive control system |
US3361231A (en) * | 1965-03-15 | 1968-01-02 | Robert P. Carroll | Hydraulic and positive braking device |
US3564367A (en) * | 1967-09-15 | 1971-02-16 | Boewe Boehler & Weber Kg Masch | Method of and apparatus for stopping machines |
US3602348A (en) * | 1967-10-26 | 1971-08-31 | Rudolf Mohr | Automatic pulse control unit for the drive of cutting machines for paper, cardboard or the like |
-
1971
- 1971-11-11 US US00197716A patent/US3741357A/en not_active Expired - Lifetime
-
1972
- 1972-09-22 IT IT29527/72A patent/IT967745B/it active
- 1972-09-28 DE DE2247632A patent/DE2247632C2/de not_active Expired
- 1972-10-06 JP JP47099972A patent/JPS5242981B2/ja not_active Expired
- 1972-10-09 GB GB4646572A patent/GB1368524A/en not_active Expired
- 1972-10-18 FR FR7237559A patent/FR2159893A5/fr not_active Expired
- 1972-11-08 CA CA156,038A patent/CA974628A/en not_active Expired
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2874343A (en) * | 1953-08-25 | 1959-02-17 | Floyd G Steele | Digital servo |
US2853900A (en) * | 1953-12-17 | 1958-09-30 | Hillyer Instr Company | Automatic precision control device |
GB803268A (en) * | 1956-07-17 | 1958-10-22 | Francis Henry Shepard Jr | Intermittent drive apparatus |
US3224690A (en) * | 1963-04-15 | 1965-12-21 | Rudolph G Holman | Machine for winding a ball |
US3277355A (en) * | 1963-12-23 | 1966-10-04 | Gen Electric | Terminal condition predictive control system |
US3361231A (en) * | 1965-03-15 | 1968-01-02 | Robert P. Carroll | Hydraulic and positive braking device |
US3564367A (en) * | 1967-09-15 | 1971-02-16 | Boewe Boehler & Weber Kg Masch | Method of and apparatus for stopping machines |
US3602348A (en) * | 1967-10-26 | 1971-08-31 | Rudolf Mohr | Automatic pulse control unit for the drive of cutting machines for paper, cardboard or the like |
Non-Patent Citations (1)
Title |
---|
IBM Technical Disclosure Bulletin Vol. 14 No. 8 January 1972 Pgs. 2501 and 2502. * |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3880421A (en) * | 1972-05-08 | 1975-04-29 | Grapha Holding Ag | Method and arrangement for handling streams of sheet goods |
US4440387A (en) * | 1977-04-08 | 1984-04-03 | Ricoh Company, Ltd. | Sheet feed apparatus |
US4610533A (en) * | 1981-01-20 | 1986-09-09 | Canon Kabushiki Kaisha | Automatic document feeding device |
US4455018A (en) * | 1981-05-11 | 1984-06-19 | International Business Machines Corporation | Document feeder electronic registration gate |
US5480131A (en) * | 1982-01-25 | 1996-01-02 | Canon Kabushiki Kaisha | Paper feeding device |
US4538717A (en) * | 1982-02-16 | 1985-09-03 | Danfoss A/S | Control apparatus for a step drive |
US4613125A (en) * | 1983-01-20 | 1986-09-23 | Heidelberger Druckmaschinen Ag | Method and device for feeding sheets in register in a sheet-processing machine |
US4519700A (en) * | 1983-12-28 | 1985-05-28 | International Business Machines Corporation | Electronically gated paper aligner system |
US4653008A (en) * | 1984-06-21 | 1987-03-24 | Iwatsu Electric Co., Ltd. | Method of controlling platemaking positions and errors |
US4657236A (en) * | 1984-07-20 | 1987-04-14 | Mitsubishi Jukogyo Kabushiki Kaisha | Sheet delivery device |
US4877234A (en) * | 1988-08-02 | 1989-10-31 | Xerox Corporation | Sheet turning and registration system |
US4865309A (en) * | 1988-08-04 | 1989-09-12 | Cluett, Peabody & Co., Inc. | Method and apparatus for aligning workpieces of variable lengths |
US5050858A (en) * | 1989-01-09 | 1991-09-24 | Alps Electric Co., Ltd. | Sheet feed control method |
US5620077A (en) * | 1994-06-01 | 1997-04-15 | Electric Vehicle Controllers Ltd. | Fail-safe brake actuation system |
US5538118A (en) * | 1994-10-19 | 1996-07-23 | Reell Precision Manufacturing Corporation | Electro-mechanical indexing clutch & method |
US6176483B1 (en) * | 1997-03-12 | 2001-01-23 | Bell & Howell Mail And Messaging Technologies Company | High speed document separator and sequencing apparatus |
US11117737B2 (en) | 2012-11-12 | 2021-09-14 | Southwire Company, Llc | Wire and cable package |
US11858719B2 (en) | 2012-11-12 | 2024-01-02 | Southwire Company, Llc | Wire and cable package |
Also Published As
Publication number | Publication date |
---|---|
FR2159893A5 (de) | 1973-06-22 |
CA974628A (en) | 1975-09-16 |
DE2247632A1 (de) | 1973-05-17 |
JPS5242981B2 (de) | 1977-10-27 |
DE2247632C2 (de) | 1982-04-01 |
GB1368524A (en) | 1974-09-25 |
JPS4854667A (de) | 1973-08-01 |
IT967745B (it) | 1974-03-11 |
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