[0001] The present invention relates to apparatus for providing reciprocating rotary drive
to the detaching rollers of a combing machine, of the type comprising at least one
detaching roller with a fixed axis and hydraulic drive means actuated by pressurised
fluid through at least one distributor valve and kinematically connected to the at
least one detaching roller to rotate it in both senses about the said axis.
[0002] It is known that, in the spinning of cotton, linen and long fibres in general, the
combing operation is carried out by a combing machine having a circular comb which
rotates continuously, a straight comb, a movable gripper unit which substantially
reciprocates, and detaching rollers. In each combing cycle of the machine, the detaching
rollers must first rotate backwards through a predetermined angle to enable a predetermined
length of the fibres which have already been combed to be superposed on those still
to be combed and must then rotate forwards through a greater angle to advance the
fibres to be combed.
[0003] It is equally well known that, in the combing operation, it is of fundamental importance
not only that the detaching rollers should be rotated through a given angle in one
sense and through a different angle in the opposite sense but also that the rotations
should take place with suitable laws of motion. More particularly, in order to avoid
the combs carrying away the long fibres during the combing operation, it is necessary
for the forward rotation of the detaching rollers to occur with a high initial acceleration
and with a subsequent phase at constant velocity while it is best that the reverse
rotation of these rollers should be rapid.
[0004] In combing machines in current use, the rotary drive for the detaching rollers is
derived from the main transmission of the combing machine.
[0005] However, the provision of derived rotary drive for the detaching rollers has the
disadvantage of requiring the provision of very expensive and complicated mechanical
transmissions. Moreover because of the high operating rate of the combing machine,
the constituent parts of the transmissions are subject to high accelerations and thus
to high dynamic stresses.
[0006] A further problem of these transmissions lies in the difficulty of driving the detaching
rollers so that their movements accord with the desired law of motion and of varying
the drive appropriately in a simple manner so as to optimise the law governing the
movements of the detaching rollers according to the type of fibre to be combed.
[0007] US Patent 3277790 discloses combing machines in which the reciprocating rotary drive
for the detaching rollers is provided by an hydraulic motor supplied with pressurised
fluid through a mechanically-controlled distributor valve.
[0008] In order to drive the slide of the distributor valve, however, these machines require
a very complicated cam system which has the disadvantages of being difficult to design,
difficult to calibrate and not very satisfactory from the point of view of long-term
reliability and precision in use following the inevitable wear of the parts.
[0009] Other combing machines have been proposed in which the reciprocating rotary drive
for the detaching rollers is provided by one or more electric motors coupled to the
detaching rollers by reduction systems.
[0010] This solution is not very satisfactory, however, since the electric motors intended
for this use must operate intermittently and thus under conditions far from their
optimum operating conditions so that, to obtain the power needed to drive the detaching
rollers without causing excessive heating of the electric motors, it is necessary
to use over-dimensioned electric motors. The inertia of the rotors of these motors
also impedes the movement of the detaching rollers in accordance with the desired
law of motion.
[0011] The present invention is based on the technical problem of devising apparatus for
providing reciprocating rotary drive to the detaching rollers of a combing machine
which has structural and functional characteristics such as to overcome the problems
mentioned with reference to prior-art combing machines.
[0012] This problem is solved by an apparatus for providing reciprocating rotary drive to
the detaching rollers of a combing machine of the type specified, which is characterised
in that the at least one distributor valve is electrically operated and in that it
includes a first sensor which generates a signal correlated with the progress of the
combing machine operating cycle, a second sensor which generates a signal correlated
with the angular position of the at least one detaching roller and an electronic control
and command unit connected to the first and second sensors for controlling the operation
of the distributor valve in dependence on the signals generated by the first and second
sensors.
[0013] Further characteristics and advantages of the apparatus according to the present
invention will become apparent from the description of several embodiments given below,
purely by way of non-limitative example, with reference to the appended drawings,
in which:
- Figure 1 is a schematic view of apparatus according to the present invention,
- Figures 2, 3 and 4 are views of a detail of the apparatus of Figure 1,
- Figure 5 shows a different embodiment of a detail of the apparatus of Figure 1, and
- Figures 6 and 7 show different embodiments of the apparatus according to the present
invention.
[0014] With reference to Figures 1 to 4, apparatus for providing reciprocating rotary drive
to the detaching rollers of a combing machine is generally indicated 1.
[0015] The combing machine includes a continuously-rotating circular comb, a straight comb
and a movable gripper unit which substantially reciprocates, which, being of known
type, are not shown in the drawings and are not described in detail below in order
not to burden the present description.
[0016] The combing machine includes two parallel detaching rollers 3 with axes A-A, located
adjacent each other at a predetermined spacing D, each of which has an associated
pressure roller 4 located parallel to and above it, in pressing contact therewith.
The combing machine can thus be seen to include two pairs 2 of parallel rollers each
of which is constituted by a detaching roller 3 and a respective pressure roller 4
the peripheral surfaces of which are in pressing contact so that they are coupled
together for rotation. The detaching rollers 3 and the pressure rollers 4 are rotatably
supported at their ends by a frame 5 of the combing machine (Figure 2).
[0017] The detaching rollers 3 of each pair 2 are kinematically connected together by a
toothed transmission so that they are coupled together for rotation in the same sense.
In the embodiment shown, the transmission is achieved by the keying of a gear 6 to
each end of the detaching rollers 3 and the connection of the gears 6 of one detaching
roller 3 to the corresponding gears 6 of the other detaching roller 3 by respective
identical idle gears 7 and 8 supported for rotation by the frame 5 of the combing
machine.
[0018] The apparatus 1 includes an hydraulic motor 9 of known type, the rotary drive shaft
10 of which is connected for rotation to the hub of the idle gear 7. The hydraulic
motor 9 is driven through an hydraulic distributor 11 by pressurised fluid from an
hydraulic circuit 12 including a fluid reservoir 13, a motor pump unit 14 mounted
on a duct P which puts the reservoir 13 in fluid communication with an inlet I of
the hydraulic distributor 11 and a duct T connecting an outlet O of the hydraulic
distributor 11 to the reservoir 13. The hydraulic circuit 12 further includes elements
such as filters, pressure switches, surge chambers, non-return valves etc. which,
being of known type, are not shown in the drawings and are not described in detail
below in order not to burden the present description but which however are included
as far as necessary for the proper operation of the equipment.
[0019] The hydraulic distributor 11 is of the proportional type with an electromagnetically
controlled distributor slide 15 biased into a central closed position (Figure 3) by
a centring spring. Besides the inlet I and the outlet O the hydraulic distributor
11 also have two connections A and B in fluid communication with the hydraulic motor
9. The movement of the distributor slide 15 enables the inlet I and the outlet O of
the hydraulic distributor 11 to be put into fluid communication with the connections
A and B respectively or vice versa.
[0020] The operation of the hydraulic distributor 11 is controlled by an electronic control
unit 31 including an electronic amplifier 16 and an electronic data-processing unit
19.
[0021] The electronic amplifier 16 is connected through an electrical conductor L1 to electromagnets
17 which drive the movements of the distributor slide 15. In addition, the electronic
amplifier 16 is connected through a conductor S1 to a position detector 18, for example
of the LVDT (linear variable differential transformer) type, associated with the distributor
slide 15 and which can supply the electronic amplifier 16 with a signal related to
the position of the distributor slide 15.
[0022] The electronic data-processing unit 19 is interfaced with the electronic amplifier
16 and is connected through an electrical conductor S2 to a sensor 20, for example
an encoder, associated with the idle gear 8. The sensor 20 supplies the electronic
data-processing unit 9 with a signal related to the angular position of the idle gear
8 and hence of the detaching rollers 3.
[0023] The electronic data-processing unit 19 is connected by an electrical conductor S3
to a sensor 32 which is associated with the circular comb and supplies the electronic
data-processing unit 19 with an electrical signal related to the angular position
of the circular comb. Since the operating cycle of the combing machine is repeated
on each complete rotation of the circular comb, this electrical signal is thus correlated
with the progress of the machine operating cycle.
[0024] In a preferred embodiment, the electronic data-processing unit 19 includes a microprocessor
21 (CPU) which is interfaced with a video-keyboard unit 22, with RAM and EPROM memories
23, with an analog/digital signal converter 24 and with a data input/output card 25
respectively.
[0025] The analog/digital signal converter 24, through a conductor L2, supplies the electronic
amplifier 16 with a signal to be amplified for controlling the movement of the distributor
slide 15.
[0026] The data input/output card 25 is connected through the conductors S2 and S3 to the
sensor 20 associated with the idle gear 8 and with the sensor 32 associated with a
circular comb respectively, while it supplies the electronic amplifier 16 with an
enabling signal through a conductor S4.
[0027] The hydraulic distributor 11 may be replaced by an electrically-controlled, hydraulically-driven
servovalve 26 for example of known two-stage type with nozzles 27 and a flapper plate
28 (Figure 5). The first stage of the servovalve 26 comprises a torque motor 29 which
is connected to the electronic amplifier 16 through the conductor L1 and drives the
movement of the flapper plate 28 between the nozzles 27. The second stage comprises
a distributor slide 30 which enables an inlet I and an outlet O to be connected to
respective connections A and B connected to the hydraulic motor 9 and vice versa.
The fluid of the hydraulic circuit 12 acts on opposite end faces of the distributor
slide 30 with an equal pressure only when the flapper plate 28 is equidistant from
the nozzles 27. Consequently, when the torque motor 29 moves the flapper plate 28
towards one of the nozzles 27, the pressure difference which is set up between the
ends of the distributor slide 30 causes the slide itself to move.
[0028] The servovalve 2 has an advantage over the hydraulic distributor 11 in that it moves
the distributor slide 30 by means of the power supplied by the hydraulic circuit 12
on which the regulation is effected since the torque motor 29, through the conductor
L1, takes only the power needed to position the flapper plate 28 between the nozzles
27.
[0029] In operation of the apparatus 1, the fibres to be combed pass through the gripper
unit, are combed by the circular comb and by the straight comb and pass between the
detaching roller 3 and pressure roller 4 of each pair 2, from which the fibres are
drawn.
[0030] At each rotation of the circular comb, the detaching rollers 3, as already stated
in the introduction to the present description, rotate in the sense opposing the advance
of the fibres and then rotate in the opposite sense through a greater angle.
[0031] The reciprocating rotation of the detaching rollers 3 through different angles is
effected by the connection of the connections A and B of the hydraulic distributor
11 alternately in fluid communication with the ducts P and T of the hydraulic circuit
12 by suitable movement of the distributor slide 15 so as to rotate the hydraulic
motor 9 since a predetermined rotation of the drive shaft 10 of the hydraulic motor
9 corresponds to a rotation of the detaching rollers 3 through an angle which depends
on the transmission ratio between the idle gears 7 and 8 and the gears 6.
[0032] The movement of the distributor slide 15 is controlled by the electronic data-processing
unit 19 which supplies the electronic amplifier 16 with an electrical control signal
which depends on the signals received from the sensor 20 associated with the idle
gear 8 and the sensor 32 associated with the circular comb. The control signal, after
being processed appropriately by the electronic amplifier 16 in dependence on the
signal supplied by the position detector 18 to the electronic amplifier 16, is fed
to the electromagnets 17 of the hydraulic distributor 11 or, in the case of the servovalve
26, to the torque motor 29, so as to drive the required movement of the distributor
slide 15.
[0033] It should be stressed that the apparatus according to the present invention enables
the movements of the distributor slide to be governed accurately and appropriately
by the electronic control and command unit 31, which enables the flow of pressurised
fluid to the hydraulic motor 9 to be regulated precisely so as to rotate the detaching
rollers 3 through different angles in opposite senses as required for the correct
operation of the combing machine.
[0034] To advantage, it is possible to vary the law of motion which governs the rotation
of the detaching rollers by varying the parameters set in the memory of the electronic
data-processing unit 19 so as to satisfy various requirements.
[0035] With reference to Figures 6 and 7, respective devices according to the present invention
for providing reciprocating rotary drive to the detaching rollers of a combing machine
are generally indicated 601 and 701, these parts which are structurally and functionally
equivalent to corresponding parts of the apparatus 1 being indicated by the same reference
numerals and not being described below so as not to burden the present description
to no purpose.
[0036] In the apparatus 601, the hydraulic drive means are constituted by two double acting
hydraulic actuators 602 each having a piston head 603 defining two variable-volume
chambers 604 and 605 within the actuator cylinder and a rod 606 fixed to the piston
head 603.
[0037] The rod 606 of each piston 603 is kinematically connected to a detaching roller 3
by a known rack and pinion transmission and a unidirectional clutch device which enables
the reciprocating rectilinear movement of the piston 603 to be converted into discontinuous
rotary drive for the detaching roller 3. In the embodiment shown, this transmission
comprises, for each of the two hydraulic actuators 602, a rack 607 fixed for translational
movement with the piston 603 and a pinion 608 meshed with the teeth of the rack 607
and keyed to a detaching roller 3 through a unidirectional clutch device 609, also
known as a free wheel, which can transmit drive torque to the detaching roller 3 in
only one rotational sense. In order to enable the detaching rollers to effect reciprocating
movements through different angles, one of the two unidirectional clutch devices 609
transmits torque and rotational drive to the detaching roller 3 in the opposite sense
from those transmitted by the other unidirectional clutch device 609, as will become
clearer in the description below.
[0038] For each hydraulic actuator 602, the apparatus 601 includes an hydraulic distributor
610 similar to the distributor 11 described above, having its inlet I and its outlet
O respectively in fluid communication with the ducts P and T of the hydraulic circuit
12 and the connections A and B respectively in fluid communication with the variable-volume
chambers 604 and 605 of the hydraulic actuator 602.
[0039] Preferably the racks 607 are arranged, relative to the pistons 603 to which they
are connected so that they supply pressurised fluid to one of the two variable-volume
chambers 604 while simultaneously connecting the other to exhaust, or vice versa,
so as to move the piston 603 of each hydraulic actuator 602 to rotate the pinions
608 in the same sense.
[0040] The apparatus 601 further includes a manually-operable hydraulic distributor 611
having an inlet I connected to the pressurised fluid duct P, an outlet O connected
to the duct T of the hydraulic circuit 12 and two connections A and B connected respectively
in fluid communication with the connections A and B of the two hydraulic distributors
610. The hydraulic distributor 611 enables the pistons 603 of the two hydraulic actuators
602 to be put in phase with each other.
[0041] In exactly the same manner as that described for the hydraulic distributor 11, in
use of the apparatus 601, the two hydraulic distributors 610 are controlled by the
electronic amplifier 16 independently of each other in dependence on the electrical
signal transmitted to the latter by the electronic data processing unit 19.
[0042] When pressurised fluid is supplied from the duct P into the variable-volume chambers
604 of the two hydraulic actuators 602 and the variable-volume chambers 605 are connected
simultaneously to exhaust, the two pinions 608 rotate in the same sense and, as indicated
above, only one of the two unidirectional clutch devices is able to transmit rotational
drive to the respective detaching roller 3. When, on the other hand, pressurised fluid
from the duct P is supplied to the variable-volume chambers 605 of the two hydraulic
actuators 602 and at the same time the variable-volume chambers 604 are connected
to exhaust, the two pinions 608 rotate in the opposite sense and rotational drive
is transmitted to the detaching roller by the other unidirectional clutch device 609.
[0043] From the above it will be clear that the length of travel of the piston 603 of one
of the two hydraulic actuators 602 determines the amplitude of the rotation of the
detaching rollers 3 in one sense while the amplitude of the rotation of the detaching
rollers 3 in the other sense is determined by the travel of the piston 603 of the
other of the two hydraulic actuators 602.
[0044] Thus by varying the parameters set in the memory of the electronic data processing
unit 19, it is possible to vary the law of motion which governs the rotation of the
detaching rollers 3.
[0045] In the apparatus 701, the hydraulic drive means are constituted by a double-acting
hydraulic actuator 702 which includes a piston 703 defining two variable-volume chambers
704 in the hydraulic actuator 702 and a rod 705 connected to the piston 703.
[0046] The rod 705 is fixed for translational movement with a rack 706 meshed with a pinion
707 kinematically connected to the hub of the idle gear 7 through a braked clutch
unit 708 of known type.
[0047] The braked clutch unit 708 comprises a friction disc fixed to an input shaft 709
to which the pinion 707 is keyed, a braked clutch disc fixed to an output shaft 710
to which the idle gear 7 is keyed, actuators, for example of electro-pneumatic type,
for moving the clutch disc into engagement with the friction disc and friction means
for braking the clutch disc when it is disengaged from the friction disc.
[0048] An electronic control system 711 is connected to the braked clutch unit 708 by a
conductor L3 and is connected to the electronic control and command unit 31 and, more
precisely, to the electronic data processing unit 19, by an electrical conductor L4.
Depending on the signal received from the electronic data processing unit 19, the
electronic control system 711 causes the braked clutch disc to engage with the friction
disc so as to connect the output shaft 710 rigidly for rotation with the input shaft
709.
[0049] The apparatus 701 includes an hydraulic distributor 712 which is the same as the
distributor 11 described previously having an input I and an outlet O respectively
in fluid communication with the ducts P and T of the hydraulic circuit 12 and the
connections A and B respectively in fluid communication with the variable-volume chambers
704 of the hydraulic actuator 702.
[0050] In a manner entirely similar to that described for the hydraulic distributor 11,
in use of the apparatus 701, the hydraulic distributor 712 is controlled by the electronic
amplifier 16 in dependence on the electrical signal transmitted to the latter by the
electronic data processing unit 19.
[0051] The reciprocating rotation of the detaching rollers is achieved by the alternate
supply of pressurised fluid from the hydraulic circuit 12 into one of the two variable
volume chambers 704 of the hydraulic actuator 702 and the simultaneous connection
of the other variable-volume chamber 704 to exhaust. By controlling the engagement
and disengagement of the braked clutch disc and the friction disc through the electronic
control system 711, it is thus possible to rotate the detaching rollers 3 in the two
senses through different angles.
[0052] The law of motion which governs the rotation of the detaching rollers 3 can be varied
by varying the parameters set in the memory of the electronic data processing unit
19.
[0053] As may be appreciated from the above, the apparatus for providing reciprocating rotary
drive to the detaching rollers of a combing machine of the present invention enables
the requirements referred to in the introduction to the present description to be
satisfied while overcoming the problems of prior-art combing machines at the same
time.
[0054] A further advantage of the apparatus according to the present invention lies in the
fact that it enables the law of motion which governs the rotation of the detaching
rollers to be varied in a simple manner so as to optimise the operation of the machine
to suit the type of fibres being combed.
[0055] Another advantage of the apparatus according to the present invention lies in the
fact that it is structurally and functionally simple so as to improve the reliability
of the combing machine compared with that of prior-art machines.
[0056] Obviously an expert in the art may make numerous modifications and variations to
the apparatus for supplying reciprocating rotary drive to the detaching rollers of
a combing machine as described above in order to satisfy various specific requirements,
all of which however fall within the scope of protection of the invention as defined
by the following claims.
[0057] Thus, for example, the combing machine may include a larger number of detaching rollers
and the sensor associated with the circular comb may be replaced by a sensor associated
with part of the combing machine which moves cyclically during each working cycle
of the machine.
1. Apparatus for providing reciprocating rotary drive to the detaching rollers of a combing
machine, of the type comprising at least one detaching roller (3) having a fixed axis
(A-A) and hydraulic drive means (9; 602; 702) actuated by pressurised fluid through
at least one distributor valve (11; 26; 610; 712) and kinematically connected to the
at least one detaching roller (3) to rotate it in both senses about the axis (A-A),
characterised:
- in that the at least one distributor valve (11; 26; 610; 712) is electrically operated,
and
- in that it includes a first sensor (32) which generates a signal correlated with
the progress of the combing machine operating cycle, a second sensor (20) which generates
a signal correlated with the angular position of the at least one detaching roller
(3) and an electronic control and command unit (31) connected to the first sensor
(32) and to the second sensor (20) for controlling the operation of the distributor
valve (11; 26; 610; 712) in dependence on the signals generated by the first sensor
(32) and the second sensor (20).
2. Apparatus according to Claim 1, characterised in that it includes a plurality of detaching
rollers (3) kinematically connected together.
3. Apparatus according to Claim 1, characterised in that the hydraulic drive means comprise
an hydraulic motor (9).
4. Apparatus according to Claim 1, characterised in that the hydraulic drive means comprise,
for each of the two senses of rotation of the detaching roller (3), a double-acting
hydraulic actuator (602) having a rod (606) connected to the at least one detaching
roller (3) by a rack (607) and pinion (608) transmission and a unidirectional clutch
device (609).
5. Apparatus according to Claim 4, characterised in that one of the unidirectional clutch
devices (609) transfers rotational drive to the detaching roller (3) in the opposite
sense from that transmitted by the other unidirectional clutch device (609).
6. Apparatus according to Claim 4, characterised in that each hydraulic actuator (602)
is supplied with pressurised fluid through a respective distributor valve (610).
7. Apparatus according to Claim 1, characterised in that the drive means comprise a double-acting
hydraulic actuator (702) having a rod (705) connected to the at least one detaching
roller (3) by a rack (706) and pinion (707) transmission and a braked clutch unit
(708).
8. Apparatus according to Claim 7, characterised in that the engagement and disengagement
of the braked clutch unit (708) is activated by an electronic control system (711)
in dependence on the signals generated by the first sensor (32) and the second sensor
(20).
9. Apparatus according to Claim 8, characterised in that the electronic control system
(711) is interfaced with the electronic control and command unit (31).
10. Apparatus according to Claim 1, characterised in that the electronic control and command
unit (31) comprises an electronic amplifier (16) and a data processing unit (19) interfaced
with each other.
11. Apparatus according to Claim 1, characterised in that the distributor valve (11; 26;
610; 712) has an associated position detector (18) which supplies the electronic control
and command unit (31) with a signal correlated with the operating position of the
distributor valve (11; 26; 610; 712).
12. Apparatus according to Claim 1, characterised in that the at least one distributor
valve (11; 26; 610; 712) is of proportional type.
13. Apparatus according to Claim 1, characterised in that the at least one distributor
valve (11; 26; 610; 712) is an hydraulic distributor (11; 610; 712) with a distributor
slide (15).
14. Apparatus according to Claim 13, characterised in that the hydraulic distributor (11;
610; 712) is electromagnetically controlled.
15. Apparatus according to Claim 1, characterised in that the at least one distributor
valve is a servovalve (26).
16. Apparatus according to Claim 15, characterised in that the servovalve (26) is electrically
controlled and hydraulically operated.
1. Gerät zum Bereitstellen eines Hin- und Herdrehantriebs für die Abreißzylinder einer
Kämmaschine der Gattung mit mindestens einem Abreißzylinder (3) mit einer festen Achse
(A-A) und hydraulischen Antriebsmitteln (9; 602; 702), die durch unter Druck gesetztes
Fluid über mindestens ein Verteilerventil (11; 26; 610; 712) betätigt werden und kinematisch
mit dem mindestens einen Abreißzylinder (3) verbunden sind, um ihn in beiden Drehrichtungen
um die Achse (A-A) zu drehen, gekennzeichnet:
- dadurch, daß das mindestens eine Verteilerventil (11; 26; 610; 712) elektrisch betrieben
wird, und
- dadurch, daß es einen ersten Sensor (32) umfaßt, der ein Signal erzeugt, das mit
dem Fortgang des Betriebszyklus der Kämmaschine korreliert ist, einen zweiten Sensor
(20), der ein Signal erzeugt, das mit der Winkelstellung des mindestens einen Abreißzylinders
(3) korreliert ist, und eine elektronische Steuer- und Befehlseinheit (31), die mit
dem ersten Sensor (32) und dem zweiten Sensor (20) verbunden ist, um den Betrieb des
Verteilerventils (11; 26; 610; 712) in Abhängigkeit von den durch den ersten Sensor
(32) und den zweiten Sensor (20) erzeugten Signalen zu steuern.
2. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß es eine Mehrzahl von Abreißzylindern
(3) umfaßt, die kinematisch miteinander verbunden sind.
3. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß die hydraulischen Antriebsmittel
einen Hydromotor (9) umfassen.
4. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß die hydraulischen Antriebsmittel
für jede der beiden Drehrichtungen des Abreißzylinders (3) einen doppeltwirkenden
hydraulischen Aktuator (602) mit einer Stange (606) haben, die mit dem mindestens
einen Abreißzylinder (3) über ein Zahnstangen- (607) und Ritzel- (608) Getriebe und
eine Richtungskupplung (609) verbunden ist.
5. Gerät nach Anspruch 4, dadurch gekennzeichnet, daß eine der Richtungskupplungen (609)
einen Drehantrieb auf den Abreißzylinder (3) in Gegenrichtung des von der anderen
Richtungskupplung (609) übertragenen überträgt.
6. Gerät nach Anspruch 4, dadurch gekennzeichnet, daß jeder hydraulische Aktuator (602)
über ein entsprechendes Verteilerventil (610) mit unter Druck stehendem Fluid gespeist
wird.
7. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß die Antriebsmittel einen doppeltwirkenden
hydraulischen Aktuator (702) mit einer Stange (705) umfassen, die mit dem mindestens
einen Abreißzylinder (3) über ein Zahnstangen- (706) und Ritzel- (707) Getriebe und
eine gebremste Kupplungseinheit (708) verbunden ist.
8. Gerät nach Anspruch 7, dadurch gekennzeichnet, daß das Ein- und Ausrücken der gebremsten
Kupplungseinheit (708) durch ein elektronisches Steuersystem (711) in Abhängigkeit
von den durch den ersten Sensor (32) und den zweiten Sensor (20) erzeugten Signalen
aktiviert wird.
9. Gerät nach Anspruch 8, dadurch gekennzeichnet, daß das elektronische Steuersystem
(711) über eine Schnittstelle mit der elektronischen Steuer- und Befehlseinheit (31)
verbunden ist.
10. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß die elektronische Steuer- und Befehlseinheit
(31) einen elektronischen Verstärker (16) und eine Datenverarbeitungseinheit (19)
umfaßt, die über eine Schnittstelle miteinander verbunden sind.
11. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß das Verteilerventil (11; 26; 610;
712) einen zugehörigen Stellungsdetektor (18) hat, der die elektronische Steuer- und
Befehlseinheit (31) mit einem Signal speist, das mit der Betriebsstellung des Verteilerventils
(11; 26; 610; 712) korreliert ist.
12. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß das mindestens eine Verteilerventil
(11; 26; 610; 712) von proportional wirkender Art ist.
13. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß das mindestens eine Verteilerventil
(11; 26; 610; 712) ein hydraulischer Verteiler (11; 610; 712) mit einem Verteilerschieber
(15) ist.
14. Gerät nach Anspruch 13, dadurch gekennzeichnet, daß der hydraulische Verteiler (11;
610; 712) elektromagnetisch gesteuert ist.
15. Gerät nach Anspruch 1, dadurch gekennzeichnet, daß das mindestens eine Verteilerventil
ein Servoventil (26) ist.
16. Gerät nach Anspruch 15, dadurch gekennzeichnet, daß das Servoventil (26) elektrisch
gesteuert und hydraulisch betrieben ist.
1. Dispositif pour réaliser l'entraînement en rotation en va-et-vient des rouleaux arracheurs
d'une machine de peignage, du type comprenant au moins un rouleau arracheur (3) possédant
un axe fixe (A-A) et des moyens d'entraînement hydraulique (9 ; 602 ; 702) actionnés
par un fluide sous pression par l'intermédiaire d'au moins une valve formant distributeur
(11 ; 26 ; 610 ; 712) et raccordés de façon cinématique à au moins un rouleau arracheur
(3) pour le faire tourner dans les deux sens autour de l'axe (A-A), caractérisé
- en ce que la au moins une valve formant distributeur (11 ; 26 ; 610 ; 712) est actionnée
électriquement, et
- en ce qu'il comporte un premier capteur (32) qui produit un signal corrélé à la
progression du cycle de fonctionnement de la machine de peignage, un second capteur
(20) qui produit un signal corrélé à la position angulaire du au moins un rouleau
arracheur (3) et une unité de contrôle et de commande électronique (31) connectée
au premier capteur (32) et au second capteur (20) pour commander le fonctionnement
de la valve formant distributeur (11 ; 26 ; 610 ; 712) en fonction des signaux produits
par le premier capteur (32) et par le second capteur (20).
2. Dispositif selon la revendication 1, caractérise en ce qu'il comprend une pluralité
de rouleaux arracheurs (3) raccordés entre eux selon une liaison cinématique.
3. Dispositif selon la revendication 1, caractérise en ce que les moyens d'entraînement
hydraulique comprennent un moteur hydraulique (9).
4. Dispositif selon la revendication 1, caractérisé en ce que les moyens d'entraînement
hydraulique comprennent, pour chacun des deux sens de rotation du rouleau arracheur
(3), un actionneur hydraulique à double effet (602) qui comporte une tige (606) devant
être raccordée au au moins un rouleau arracheur (3) par une transmission à crémaillère
(607) et pignon (608), et un dispositif d'embrayage unidirectionnel (609).
5. Dispositif selon la revendication 4, caractérisé en ce que l'un des dispositifs d'embrayage
unidirectionnel (609) transfère l'entraînement en rotation au rouleau arracheur (3)
dans le sens opposé à l'entraînement transmis par l'autre dispositif d'embrayage unidirectionnel
(609).
6. Dispositif selon la revendication 4, caractérisé en ce que chaque actionneur hydraulique
(602) est alimenté par un fluide sous pression par l'intermédiaire d'une valve respective
formant distributeur (610).
7. Dispositif selon la revendication la revendication 1, caractérisé en ce que les moyens
d'entraînement comprennent un actionneur hydraulique à double effet (702) comportant
une tige (705) raccordée au au moins un rouleau arracheur (3) par une transmission
à crémaillère (706) et pignon (707) et une unité d'embrayage freinée (708).
8. Dispositif selon la revendication 7, caractérisé en ce que l'enclenchement et le désenclenchement
de l'unité d'embrayage freinée (708) sont activés par un système de commande électronique
(711) en fonction des signaux produits par le premier capteur (32) et le second capteur
(20).
9. Dispositif selon la revendication 8, caractérisé en ce que le système de commande
électronique (711) est relié par interface à l'unité de contrôle et de commande électronique
(31).
10. Dispositif selon la revendication 1, caractérisé en ce que l'unité de contrôle et
de commande électronique (31) comprend un amplificateur électronique (16) et une unité
de traitement de données (19) reliés entre eux par interface.
11. Dispositif selon la revendication 1, caractérisé en ce que la valve formant distributeur
(11 ; 26 ; 610 ; 712) possède un détecteur de position associé (18) qui envoie à l'unité
de contrôle et de commande électronique (31) un signal corrélé à la position de fonctionnement
de la valve formant distributeur (11; 26 ; 610 ; 712).
12. Dispositif selon la revendication 1, caractérisé en ce que la au moins une valve formant
distributeur (11 ; 26 ; 610 ; 712) est du type à action proportionnelle.
13. Dispositif selon la revendication 1, caractérisé en ce que la au moins une valve formant
distributeur (11 ; 26 ; 610 ; 712) est un distributeur hydraulique (11 ; 610 ; 712)
comportant un tiroir coulissant (15).
14. Dispositif selon la revendication 13, caractérisé en ce que le distributeur hydraulique
(11 ; 610 ; 712) est commandé électromagnétiquement.
15. Dispositif selon la revendication 1, caractérisé en ce que la au moins une valve formant
distributeur est une servovalve (26).
16. Dispositif selon la revendication 15, caractérisé en ce que la servovalve (26) est
commandée électriquement et est actionnée hydrauliquement.