`Pruessel
`
`[19]
`
`[111 Patent Number:
`[45] Date of Patent:
`
`5,834,658
`Nov. 10, 1998
`
`um1111uuuni1111u01miwunimn
`
`[54] METHOD FOR MONITORING THE PATH OF
`MOVEMENT OF A PART
`
`[75]
`
`Inventor: Holger Pruessel, Buehlertal, Germany
`
`[73] Assignee: Bosch GmbH, Stuttgart, Germany
`
`[21]
`
`[22]
`
`Appl. No.:
`
`860,412
`
`PCT Filed:
`
`Oct. 22, 1996
`
`FOREIGN PATENT DOCUMENTS
`
`3034118
`
`3/1982 Germany .
`
`Primary Examiner - Robert Raevis
`Attorney, Agent, or Firm -Spencer & Frank
`
`[57]
`
`ABSTRACT
`
`§ 371 Date:
`
`[86]
`
`PCT No.:
`
`PCT /DE96/02005
`Jun. 24, 1997
`§ 102(e) Date: Jun. 24, 1997
`[87] PCT Pub. No.: WO97/15872
`
`PCT Pub. Date: May 1, 1997
`Foreign Application Priority Data
`
`[30]
`
`Oct. 25, 1995
`
`[DE]
`
`Germany
`
`195 39 577.8
`
`Int. C1.6
`[51]
`[52] U.S. Cl.
`[58] Field of Search
`
`GO5B 11/14
`73/865.9; 318/626
`73/865.9; 318/3,
`318/9, 799, 806, 830, 626, 616
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`5,278,480
`
`1/1994 Murray ..... ............................... 318/286
`
`14
`
`A method for monitoring the path of movement of a part
`which is movable toward at least one end position by means
`of a drive, wherein at least one time period is measured
`which corresponds to a selectable number of revolutions of
`a drive shaft and the at least one time period is evaluated and
`supplies a measure for a running behavior of the part.
`Immediately after the start of the drive, at least one time
`period is measured which corresponds to a selectable num-
`ber of revolutions of the drive shaft, this time period is stored
`temporarily when the drive shaft has executed a selectable
`minimum number of revolutions and, during a next start of
`the drive, the time period corresponding to the selectable
`number of revolutions of the drive shaft is measured again
`and is compared with the temporarily stored time period and
`the drive is stopped or reversed if the temporarily stored time
`period is exceeded by a selectable measure.
`
`7 Claims, 1 Drawing Sheet
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`/ 20
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`26
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`28
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`22
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`24
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`42
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`34
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`40
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`U.S. Patent
`
`Nov. 10, 1998
`
`5,834,658
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`14
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`12
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`13/
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`36
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`38
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`26
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`34
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`40
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`to
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`44
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`20
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`as--- 28
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`TG
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`1 ;
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`10 /
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`18
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`22
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`24
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`Fig.1
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`,;
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`- T1-1
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`;- T2 `
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`T3
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`Fig. 2
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`UUSI, LLC
`Exhibit 2033
`2/4
`
`
`
`5,834,658
`
`1
`METHOD FOR MONITORING THE PATH OF
`MOVEMENT OF A PART
`
`The invention relates to a method for monitoring the path
`of movement of a part which can be moved toward at least
`one end position by means of a drive, wherein at least one
`time period is measured which corresponds to a selectable
`number of revolutions of a drive shaft and the at least one
`time period is evaluated and supplies a measure for a
`running behavior of the part.
`
`5
`
`10
`
`PRIOR ART
`
`2
`period is exceeded by a selectable measure. Therefore, it is
`possible in an advantageous manner to realize a monitoring
`and thus an evaluation of the path of movement of the part
`immediately when the drive is set into operation. Thus, the
`startup phase of the drive and the associated compensation
`for play of the force transmission mechanics exerted on the
`part to be moved do not have to be considered, because two
`starting processes that immediately follow one another are
`compared with one another and thus the startup behavior
`which is identical in the two starting processes can be
`masked.
`Advantageous embodiments of the invention result from
`the further described characteristics and modifications.
`
`15
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`In the following, the invention is explained in greater
`detail in an embodiment by way of the associated drawings,
`wherein:
`FIG. 1 schematically, shows an arrangement for imple-
`20 menting the method according to the invention, and
`FIG. 2 is a time diagram of a starting process.
`
`It is known to combine parts with a drive which moves the
`parts along a path of movement. In this process, the parts can
`be moved toward at least one end position, in particular, they
`can be moved back or forth between two end positions. Parts
`which are movable in such a way are used, for example, in
`motor vehicles as electrical window lifters or electrically
`operable sliding roofs. By means of a switching means, the
`window lifters or the sliding roof can be put into motion via
`the drive, so that they are moved automatically toward their
`end position, that is, into their closed position. This involves
`the risk that a body part of a vehicle occupant gets into the
`path of movement of an automatically closing window or
`sliding roof, thus entailing a considerable risk of injury.
`It is known to equip parts that are moved in this manner
`to exhibit a closing force limitation by means of a device,
`wherein a counterforce exerted on the moved part is deter-
`mined indirectly and the drive is stopped or reversed as a
`function of the indirectly determined counterforce. For this
`purpose, for example, a time period is measured which
`corresponds to a selectable number of revolutions of a drive
`shaft of the drive, and if, in the presence of the same number
`of revolutions of the drive shaft, the time period becomes
`longer, it is inferred that there is a risk of an object or body
`part getting caught. Such a procedure is known, for example,
`from DE 30 34 118 C2.
`But the disadvantage of the known methods is that a time
`measurement takes place only at a moment which is offset 40
`in time after the start of the drive in order to take account of
`a compensation for play of the mechanical parts of the drive.
`But since during the starting phase, in which the compen-
`sation for play takes place, the part, here the window,
`already traverses a specific amount of its path of movement, 45
`which may, for example, amount to several cm, it becomes
`possible to close the window by means of a clocked opera-
`tion of the switching means without activating the protection
`against an object or body part getting caught.
`
`25
`
`30
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`35
`
`50
`
`SUMMARY AND ADVANTAGES OF THE
`INVENTION
`In contrast, the method according to the invention offers
`the advantage that the protection against an object or body
`part getting caught remains intact over the entire path of 55
`movement of the part, even in the presence of a clocked
`operation of the switching means and therewith a clocked
`setting into operation of the drive. Immediately after the start
`of the drive, at least one time period is measured, which
`corresponds to a selectable number of revolutions of the 60
`drive shaft; and this time period is stored temporarily after
`the drive shaft has gone through a further selectable mini-
`mum number of revolutions; and, during a next start of the
`drive, the time period corresponding to the selectable num-
`ber of revolutions of the drive shaft is measured again and 65
`is compared with the temporarily stored time period; and the
`drive is stopped or reversed if the temporarily stored time
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`FIG. 1 schematically shows a drive system for the posi-
`tioning of a part, identified in general by 10. The drive
`system 10 has a drive 13 which is configured as an electric
`motor 12. A drive shaft 14 of the electric motor 12 engages
`a gearing 16 which is only indicated here. Via a transmitting
`device IS, the gearing 16 is connected to a part 20 to be
`positioned. The part 20 can be moved back and forth by
`means of the drive 13 between a first end position 22 and a
`second end position 24, formed by limit stops 26 or 28,
`respectively. The electric motor 12 is connected via motor
`connection lines 30 or 32 with a control circuit 34. The drive
`shaft 14 of the electric motor 12 supports at least one signal
`generator 36 whose signals can be picked up by a sensor 38.
`The sensor 38 is connected to an evaluation circuit 40. The
`evaluation circuit 40 is connected with an input 42 of the
`control circuit 34.
`The drive system 10 illustrated in FIG. 1 can be used, for
`example, for the adjustment of electrical window lifters in
`motor vehicles. But this is only one example of the appli-
`cations that are possible. Thus, it is possible, of course, to
`use the drive system 10 for all further applications in which
`a part is movable between two end positions. These appli-
`cations are not limited to equipment options in motor
`vehicles.
`The drive system 10 illustrated in FIG. 1 has the following
`function, with it being assumed here that the system relates
`to a drive system for window lifters in motor vehicles.
`After the operation of a switching means, not shown, the
`electric motor 12 is set into operation via the control circuit
`34. In this process, the gearing 16 is engaged via the rotating
`drive shaft 14 so that the transmitting device 18 and the part
`20 move toward one of the limit stops 26 or 28 in a known
`manner. First, together with the setting into operation of the
`electric motor 12, a compensation for play of the mechanical
`components of the drive system 10 takes place, in the
`illustrated example the engagement of the drive shaft 14 into
`the gearing 16, as well as the transmission of the rotational
`movement to the transmitting device 18. The further text
`assumes that limit stop 26 is the lower stop of the window
`lifter and, correspondingly, limit stop 28 the upper stop.
`With each revolution of the drive shaft 14, a signal is
`transmitted via the at least one signal generator 36 to the
`
`UUSI, LLC
`Exhibit 2033
`3/4
`
`
`
`5,834,658
`
`3
`sensor 38 which forwards the signal to the evaluation circuit
`40. The path of movement of the part 20 can be simulated
`in the evaluation circuit 40 by means of a corresponding
`electronic circuit via the time period between directly suc-
`cessive pulses of the signal generator 36 or via the time
`period between a selectable number n of pulses of the signal
`generator 36, with each pulse, for example, corresponding to
`a full revolution of the drive shaft 14.
`In a diagram, FIG. 2 illustrates the plotting of a pulse
`sequence of the sensor 38 by way of example. With each
`start of the electric motor 12 at a moment t0, a pulse 44 is
`made available by the signal generator 36 via the sensor 38
`with each revolution of the drive shaft 14. The pulses 44 are
`counted by means of the evaluation circuit 40. In this
`process, an algorithm is prescribed for the evaluation circuit
`40, which algorithm, for example, can be selectably adjusted
`in a memory unit, not shown. This algorithm has the effect
`that, respectively after a specific number of pulses, a time
`period T is measured and stored. Thus, for example, after
`two pulses 44, that is, after two revolutions of the drive shaft
`14, a first time T1 can be picked -up, after 3.5 revolutions of
`the drive shaft 14 (for this purpose the drive shaft 14 has
`more than one signal generator 36 distributed over its
`circumference) a time T2 and after five revolutions of the
`drive shaft 14 a time T3. These times T1, T2 and T3 are
`stored temporarily in a memory means for the event when
`the drive shaft 14 executes a predeterminable minimum
`number of revolutions, that is, when a predeterminable
`minimum number of pulses 44 are picked up. During the
`pickup of the time periods T1, T2 and T3 immediately after
`the starting moment TO, an initial compensation for play of
`the mechanical parts -which was already explained -is
`also considered to the extent that the parts have an effect on
`the revolution of the drive shaft 14. Once the drive shaft 14
`has generated the predetermined minimum number of pulses
`44, the time periods Ti, T2 and T3 are stored temporarily as
`reference times within the evaluation circuit 14. The mini-
`mum number of the pulses 44 is present at a time period TG.
`Since the electric motor 12 as well as the voltage supply of
`the electric motor 12 are known per se, the theoretical
`number of pulses 44 within a specific, selectable time period
`can be calculated in advance. Based on this time period
`between two successive pulses 44, which is to be expected
`in theory, the evaluation circuit 40 recognizes whether there
`is a tendency that an object or a body part can get caught
`between the moving part 20 and the upper limit stop 28
`when the electric motor 12 stops. If there were an event
`where an object or body part is getting caught, a counter -
`force would be exerted on the moving part 20, thus leading
`to a deceleration of the number of revolutions of the electric
`motor 12, so that the time interval between successive pulses
`44 increases.
`If the evaluation circuit 40 recognizes an event where an
`object or body part is getting caught, the time periods T1, T2
`and T3 are measured again for the respective same number
`of pulses 44 during the subsequent switching on of the
`electric motor 12 and they are compared with the tempo-
`rarily stored reference values for the time periods Ti, T2 and
`T3 on the basis of the previous measurement. If the newly
`measured time periods Ti, T2 and T3 exceed the reference
`times, the actuating circuit 40 recognizes an event where an
`object or body part is getting caught, whereupon a corre-
`sponding signal is emitted to the control circuit 34 and the
`electric motor 12 is stopped or reversed, that is, rotated in the
`reverse direction. This ensures a continuous protection for
`the moving part 20 against an object or body part getting
`
`5
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`15
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`4
`caught, which protection is activated directly with the
`switching on of the electric motor 12, that is, without
`consideration of a possible compensation for play.
`The number of time periods T, which are measured and
`stored temporarily as reference times, can be selected freely
`and may, for example, be between 1 and n. The number of
`the pulses 44 for which one or several time periods T are
`picked up is also selectable. The minimum number of pulses
`44 and thus of the total time period TG, which must pass
`10 before the previously measured time periods T are stored as
`reference times, can also be selected. The corresponding
`number of pulses 44 or of the time periods T can be entered
`or predetermined separately for each specific application by
`means of the evaluation circuit 40.
`By predetermining a minimum number of pulses 44 or the
`minimum time period TG associated therewith, it is ensured
`that in case that with the first start of the electric motor 12
`an event is present where an object or body part is getting
`20 caught, the measured time periods T1, T2 and T3 cannot be
`picked up as reference values and be stored temporarily.
`I claim:
`1. Amethod for monitoring the path of movement of a part
`which is movable toward at least one end position by means
`25 of a drive, wherein at least one time period is measured
`which corresponds to a selectable number of revolutions of
`a drive shaft and the at least one time period is evaluated and
`supplies a measure for a running behavior of the part,
`characterized in that, immediately after the start of the drive,
`30 at least one time period is measured which corresponds to a
`first selectable number of revolutions of the drive shaft, this
`at least one time period is stored temporarily after the drive
`shaft has executed a further selectable minimum number of
`revolutions greater that said first selectable number of revo-
`35 lutions and, during a next start of the drive, the time period
`corresponding to the first selectable number of revolutions
`of the drive shaft is measured again and is compared with the
`temporarily stored time period and the drive is stopped or
`reversed if the temporarily stored time period is exceeded by
`40 a selectable measure.
`2. A method according to claim 1, wherein three of said
`time periods each corresponding to a different first selectable
`number of revolutions are measured, with each time period
`corresponding to a number of pulses respectively supplied
`45 by the drive.
`3. A method according to claim 2, wherein the pulses are
`generated by at least one signal generator that rotates with
`the drive shaft.
`4. A method according to claim 2, wherein an evaluation
`50 circuit receiving the pulses determines the time periods,
`stores them temporarily and compares them with the stored
`time periods of the preceding starting process for the drive.
`5. A method according to claim 2, wherein the drive is
`stopped or reversed if the time periods measured during a
`55 follow -up start of the drive exceed the temporarily stored
`time periods by a selectable measure and if during the stop
`of the drive immediately prior to the follow -up start a risk of
`an object or body part getting caught is recognized.
`6. A method according to claim 5, wherein the risk of an
`60 object or body part getting caught is recognized by an
`evaluation of the pulses during the operation of the drive.
`7. A method according to claim 1 wherein the time periods
`correspond to a given number of pulses supplied by the
`drive.
`
`65
`
`UUSI, LLC
`Exhibit 2033
`4/4
`
`