[0001] The present invention relates to a selector device for performing the programming
of rotary dobbies for actuating the heald frames in weaving looms.
[0002] It is known that the positioning of the heald frames of a weaving machine or loom,
from which the configuration of the finished fabric is obtained, must be programmed
in accordance with a predetermined sequence which defines the position which each
frame must assume upon each rotation of the main shaft of the loom.
[0003] So that the shed formed by the warp yarns can open and close alternately, allowing
the weft yarn to be inserted, the heald frames must correspondingly assume a high
position and a low position, drawing with them during this movement the corresponding
warp yarns. In order to transform the rotary movement of the main shaft into an alternating
translatory movement of the frames, a weave machine and, in particular, "dobbies"
are used, in which suitable eccentrics control the movement of the respective frames
by means of lever mechanisms.
[0004] The upward and downward movement of the heald frames must be able to be programmed
so that, at each half turn of the main shaft, the individual frame may be kept in
a high position, in a low position or displaced from one position to another. To achieve
this, the corresponding eccentric must be idle with respect thereto, to keep the associated
frame immobile, and alternately must be joined to the main shaft, to move the frame
itself: the selection device apt to perform this programming operation forms precisely
the subject of the present invention.
[0005] In the art devices for programming dobbies are known, said devices, however, having
numerous drawbacks including the need to operate at the right time and with extreme
precision the components responsible for selection of the desired state, for example
in order to stop the shaft at each half-turn, so as to have the necessary time to
cancel the previous selection and set a new one for the next half-turn. It is obvious
how programming devices of this type cause an increase in the idle time of the machine,
to the detriment of the useful working time. This is even more critical especially
in the modern weaving looms where the rates reached are of the order of several hundreds
of cycles per minute and hence the selection and operating times must necessarily
be very brief.
[0006] Another type of drawback which can be encountered in the devices of the art consists
in the high probability of errors which arise from the fact of performing a selection
in a "punctual" manner in the middle of the motion curve. In order to understand this
problem more fully, reference will be made to Fig. 1 of the accompanying drawings,
in which, by way of example, the evolution of a reference angle on the main shaft
of the loom as a function of the time and the corresponding displacement of a theoretical
selector (a) and of a selector of the known art (b and c) is shown. As can be seen,
the theoretical selector reaches its maximum displacement, which corresponds to the
operation of disengaging the engaging member which joins together the eccentric and
the main shaft, at a singular point of the curve (apex of the curve (a)): this would
be possible only if the contact between the selector and the engaging member were
able to occur in a punctual and instantaneous manner. It is obvious that this condition
cannot be realized in practice, both because the engaging member requires a discrete
time in order to engage and disengage the eccentric and the main shaft from one another
and because operation would be too critical depending on the play and the constructional
tolerances.
[0007] Furthermore, the attainment of this theoretical condition is also complicated by
the need to perform the same operations also during reverse running of the loom (a
motion condition which is often used during maintenance of the loom and repairing
of the broken yarns). In order for the selector to be able to operate in a symmetrical
manner during forwards and reverse running - as in the curve (a) - acting substantially
instantaneously on the engaging member, it would in fact be necessary for both these
elements to interact by means of two respective pointed parts: a goal which would
be difficult to achieve in practical terms since the mechanical components must in
any case interact with each other by means of discrete surfaces.
[0008] It perhaps hardly needs to be mentioned that the selection errors are reflected in
errors in the insertion of the weft, thereby resulting in time lost in order to stop
the loom, restore the preceding conditions and restart operation, taking suitable
measures to prevent the fabric being formed with apparent defects.
[0009] However, the possibility which is to be feared most is that selection may occur in
a precarious manner. In this case, if engagement between the members responsible for
selection should not occur during movement of the frames, there could be a sudden
release of the frames themselves which, dropping downwards, would result in irregular
closure of the shed with inevitable interference and possible impact with the members
for inserting the weft yarn.
[0010] In order to avoid all these said drawbacks, according to the most recent known art,
the control member, which joins the eccentric to the main shaft, consists of an engaging
lever, fixed to the eccentric, having an engaging tooth which is alternately engaged
with or disengaged from a recess formed in a member fixed to the main rotational shaft,
so as to engage and disengage, respectively, the eccentric with/from the main shaft.
The engaging lever is formed in the manner of a profile in the form of a cam with
which the end of C-shaped controlling lever interacts. In this way, the end of the
controlling lever may be brought into the trajectory of the engaging lever in advance
of the arrival of the lever itself, since the cam profile ensures that the pressing
action thereon, and the consequent disengagement of the engaging tooth, is performed
gently. It is possible, therefore, to perform these operations in a more gradual manner
- rather than being obliged to slow down brusquely rotation of the main shaft (with
consequent sudden acceleration motion laws) so as to give the operating lever the
opportunity to intervene in a punctual and precise manner on the engaging lever -
also allowing for a certain amount of tolerance in the precision of the device.
[0011] Locking of the engaging lever, both in the position where the engaging tooth is extracted
from its recess (frame idle) and in the position where the tooth is engaged (frame
which varies its position), is moreover ensured by means of a small stud which is
fixed to a connecting rod and which engages in a corresponding recess on an end of
the lever itself.
[0012] However, the drawbacks associated with the inevitable imprecision which still exists
during selection remain. The constructional and mounting tolerances cannot be nominally
respected; moreover, the friction of the cam profiles results in wear which adversely
affects, with use, the operating precision; finally, the need to perform the same
selection during both in the forwards running and reverse running results in the need
to resort to compromises in the design, to the detriment of precision.
[0013] Firstly, locking of the engaging lever on the pin is still critical: insertion of
the latter into its seat must be performed with a high degree of reliability in order
to prevent selection from occurring in a precarious manner.
[0014] A solution proposed in the known art consists in providing a resilient mounting assembly
for the pin on the connecting rod. Although this solution, in the case of inevitable
operating imprecision, reduces the risk of the pin not entering correctly its seat,
catching on the end of the engaging lever - with the possibility of accidental disengagement
and consequent drop of the corresponding heald frame - it is still not without defects
and is complex to implement.
[0015] In EP-0,485,009, on the other hand, operating imprecision is overcome by providing
a second cam portion on the engaging lever, in the region of the seat into which the
locking pin engages. This solution makes it possible to obtain a safe selection of
the engaging lever, in the extracted position or in the engaged position, keeping
the constructional tolerances within an acceptable range. However, operation is still
not entirely satisfactory. In fact, the trajectories followed by the end of the engaging
lever and - ultimately also those of the cam portion of the pin seat - cannot be always
precisely designed and are in any case variable depending on the direction of running
of the loom and the wear phenomena, so that the cam surfaces do not always manage
to function in an optimum manner.
[0016] A second category of drawbacks arises from the need to perform an equivalent selection
both during forwards running and during reverse running of the loom. Normally the
cam profile of the engaging lever is designed to perform a correct engagement and
disengagement motion of the engaging tooth during forwards running of the weaving
loom, while it is difficult to obtain the same thing for reverse running of the loom
itself. In fact, since a punctual interaction between two mechanical components (the
engaging lever and the end of the controlling lever) cannot occur, inevitably the
interaction will take place correctly in one direction (for example during forwards
running of the loom) and in advance in the opposite direction (for example during
reverse running of the loom), thus resulting in an operational phase-shift.
[0017] In fact, as can be seen in the graph (b) of Fig. 1, forwards running occurs along
the line 1, 2, 3, 4. If, however, reverse running were to occur along the same line
4, 3, 2, 1, there would be a phase advance sf during the active operation at point
3, and hence likely faulty catching of the engaging lever.
[0018] To avoid these problems, according to the known art a double actuator or a double
operating phase actuator is used, so as to cause the end of the C-shaped controlling
lever to interfere with the trajectory of the engaging lever at different times for
forwards running and for reverse running. In particular, during reverse running, actuation
of the controlling lever must occur with a phase delay sf so as to follow the line
5, 6, 7, 8 of the graph (c) of Fig. 1, where the active operation occurs at 6, i.e.
in phase with the active operation 2 of forwards running. However, the double actuator
is a delicate component which is difficult to program and costly.
[0019] The double actuator remains indispensable in the solution proposed in the Italian
Patent Application No. MI95A002037, in which a further improvement has been obtained
by providing one end of the controlling lever with an oscillating profile. This solution
solves, however, only partially the abovementioned problems of phase-displacement
between forwards running and reverse running.
[0020] All the drawbacks highlighted above are overcome in a satisfactory manner by the
device according to the invention, the innovative characteristics of which are described
in the accompanying claims.
[0021] Further characteristic features and advantages of the device according to the invention
will appear, however, more clearly from the detailed description which follows of
some preferred embodiments thereof, provided by way of example and illustrated in
the accompanying drawings, in which:
Fig. 1 is a diagrammatic view which shows, as already mentioned above, the operational
graphs of the selector device;
Figs. 2 and 3 are schematic, partial, cross-sectional views showing a rotary dobby
to which a first embodiment of the device according to the invention is applied, in
a position at the start of a half-turn and in a following position, with changing
of the position of the frame, respectively;
Figs. 2A and 3A are views similar to those of Figs. 2 and 3, at the end of the half-turn
during forwards running and in a following position, with the position of the frame
being maintained, respectively;
Figs. 2B and 3B are views on a larger scale, similar to the preceding ones, at the
end of the half-turn during forwards running, before the start of disengagement of
the engaging lever and after disengagement thereof has been completed, respectively;
Figs. 4, 5 and 6 are views similar to those of Figs. 2B and 3B, at the end of a half-turn
during reverse running, which show in detail operation of the device according to
the invention;
Figs. 7 and 8 are schematic views, with parts partially removed, of a second embodiment
of the selection device according to the invention shown complete during changing
of the position of the heald frame;
Figs. 7A and 8A are views which are similar to those of Figs. 7 and 8 and which show
the selection device during disengagement of the engaging lever;
Fig. 9 is a side elevation view, on a larger scale, of the engaging lever according
to the invention;
Fig. 10 is a side elevation view of a variation of embodiment of the engaging lever
according to the invention, enlarged on the same scale as in Fig. 9; and
Figs. 11 and 12 are views which are similar to those of Figs. 7 and 8 and which show
another embodiment of the selection device according to the invention.
[0022] As illustrated in the drawings, the device according to the invention forms part
of a dobby which comprises a rotating shaft 1 onto which there is mounted a connecting-rod
element 2 shaped so as to have a projection 2a pivotably mounted at 3a on the operating
rod 3 of the corresponding heald frame (not shown) and a substantially circular ring
2b on which two pins 2c are mounted in opposite positions.
[0023] A bearing 4 is provided in a central position on the connecting rod 2, on the inner
race of the bearing being mounted an eccentric cam 5 being able to rotate, as can
be seen further below, with respect to the shaft 1.
[0024] On the eccentric cam 5 there is pivotably mounted, by means of a rivet 6 or the like,
a rocker arm lever 7, or engaging lever, which has shaped ends 8 and 9, a seat 20
and an engaging tooth 11 on the inner side opposite to the end 9.
[0025] A spring 12 arranged between the eccentric cam 5 and the end 9 of the lever 7 exerts
a recall action on the lever 7 itself and thus tends to cause it rotate so as to move
the tooth 11 towards the axis of rotation of the shaft 1.
[0026] A disk 13, finally, is keyed coaxially on said shaft 1, on the periphery of said
disk there being formed two recesses 13a and 13b which are arranged diametrically
opposite one another with respect to the centre of rotation of the disk 13 itself.
[0027] On the disk 13 there is keyed the inner race of a bearing, on the outer race of which
the eccentric cam 5 is mounted so as to thus rotate about the shaft 1.
[0028] The disk 13 has the same lie as the lever 7 so that the tooth 11 of the latter is
able to engage with one of the two recesses 13a or 13b and disengage therefrom.
[0029] In the embodiment shown in Figs. 2 to 6, the dobby is completed by an controlling
lever 14, which is C-shaped and the ends of which, according to the invention, are
equipped with respective movable projecting profiles in the form of teeth 14a and
14b which oscillate between abutting walls 14x and 14y and are kept in position against
the former of said walls by springs 14d.
[0030] The controlling lever 14 oscillates about a pivot 14c between a first position, defined
by the biasing force of a spring 15 and by an abutment element 16, and a second position
defined, according to the invention, by the thrust exerted by a sole programming actuator
17 or single operating phase actuator, the action of which is schematically indicated
by means of an arrow A.
[0031] The dobby operates as follows: at the start of the half-turn of the shaft 1 (Fig.
2) and in the case of forwards running and programming effected with a view to varying
the position of the frame, the actuator 17 does not exert any action on the lever
14, which, being subject to the action of the spring 15, abuts against the element
16, thus leaving the rocker-arm engaging lever 7 subject to the recall action of the
spring 12, with the tooth 11 engaged in the recess 13a.
[0032] In this situation the eccentric 5 is integrally joined to the rotating disk 13 which,
rotating together with the shaft 1 during the half-turn (Fig. 3), draws with itself
in rotation the eccentric 5 and hence the connecting rod 2 which, rotating, also draws
the operating lever 3 of the frame, causing it to change position.
[0033] According to the invention, before the half-turn has been completed (Fig. 3), the
programming device 17 pre-sets the control action relating to the next half-turn,
namely in the example in question in view of keeping the frame in the previous position.
It does not exert, therefore, any action on the controlling lever 14, and the tooth
14b, when it comes into contact (Fig. 2A) with the rear surface 8a of the end 8 of
the engaging lever 7, formed with a rising front face, forces the lever 7 itself,
continuing the rotation of the disk 13, to rotate about its rivet 6, causing the tooth
11, which is provided at the opposite end, to gradually come out of the recess 13a
of the disk 13.
[0034] Once the dead centre of the half-turn has been reached (Fig. 2A), the engaging lever
7 is totally rotated outwards and engaged with the pin 2c via its seat 20, while the
tooth 11 is totally extracted from the recess 13a.
[0035] The eccentric cam 5 thus remains idle with respect to the disk 13, thus resulting
in the previous position of the heald frame controlled by the lever 3 being maintained
during the next half-turn (Fig. 3B).
[0036] Figs. 2B and 3B illustrate in detail how the engaging lever 7 is controlled during
the stages of operation of the device according to the invention described above,
in the forwards running condition.
[0037] Figs. 4, 5 and 6 show, on the other hand, in the same detail, how the engaging lever
7 is controlled during the corresponding stages of operation of the device in the
reverse running condition. As can be deduced from the illustrations, the step of engagement
of the tooth 14b of the controlling lever 14 with the engaging lever 7 takes place,
in accordance with the invention, in such a way as to provide a phase-displacement
sf (Fig. 1) in the rotation of the shaft 1 with respect to the phase in the forwards
running condition, equivalent to the idle stroke which the engaging lever 7 performs
before bringing the tooth 14b into abutment against the wall 14y. This takes place
owing to the particular system of assembly of the tooth 14b which is able to oscillate,
against the action of the spring 14d, between the abutting wall 14x and the abutting
wall 14y. Since the spring 14d exerts an action which is weaker than that of the spring
12 which biases the lever 7 against the disk 13 (or, in any case, the effect of the
former never exceeds that of the latter), when the tooth 14b engages with the end
8a of the lever 7 in the reverse running condition (Fig. 4), the lever 7 does not
undergo any displacement, whereas the tooth 14b oscillates (Fig. 5).
[0038] The phase-displacement sf makes it possible to compensate for the fact that the interaction
between the lever 7 and the tooth 14b is not "punctual" and would therefore occur
at two different points for forwards and reverse running, resulting in the loss of
selection equivalence between these two motion conditions.
[0039] According to the invention, also the opposite end 14a of the controlling lever 14
operates in a manner similar to that just described, the two ends being apt to select
the idle condition of the heald frames respectively at the top dead centre and bottom
dead centre of the operating rod 3 which acts on the frame itself.
[0040] In this way, the programming actuator 17 is always able to intervene in the same
manner, both in order to position the end 14a and to position the end 14b, no longer
having to ensure a separate synchronised selection for forwards running and for reverse
running of the loom.
[0041] The solution illustrated hitherto is totally innovative and fully solves the problems
of the known art. In particular, it ensures a very gentle selection action, drastically
reduces the deceleration dead time for performing selection itself and eliminates
the need for the double operating phase actuator.
[0042] Here it is worth considering more closely this last advantage. It must be said in
fact that the inventors have conducted their research in an area where the use of
double operating phase actuators was consolidated - a prejudice which for a long time
prevented the attainment of the advantageous solution proposed by the present invention,
which is simple, but at the same time very effective and free from malfunctions.
[0043] In the embodiment of the device which is shown in Figs. 7 to 10 and which, similar
to the preceding embodiment as regards the general structure, a rocker arm lever 7,
or engaging lever, is mounted pivotably on the eccentric 5 by way of a rivet 6, or
the like, and has a shaped rear end 8 and front end 9 from the opposite side of which
an engaging tooth 11 projects.
[0044] A spring 12 arranged between the eccentric 5 and the end 9 of the lever 7 exerts
a recall action on the lever 7 itself and thus tends to cause it to rotate so as to
move the tooth 11 towards the axis of rotation of the shaft 1.
[0045] A disk 13, finally, is mounted onto said shaft 1, coaxially therewith, and has formed
on its periphery two recesses 13a and 13b which are arranged diametrically opposite
with respect to the centre of rotation of the disk 13 itself.
[0046] On the disk 13 there is mounted the inner race of a bearing, on the outer race of
which the eccentric 5 is mounted so as to thus rotate about the shaft 1.
[0047] The disk 13 has the same lie as the lever 7 such that the tooth 11 of the latter
is able to engage with one of the two recesses 13a or 13b or disengage therefrom.
[0048] The dobby is completed by an controlling lever 14 which is C-shaped and the ends
of which are formed with suitable profiles 24a and 24b.
[0049] The controlling lever 14 oscillates about a pivot 14c between a first position, defined
by the pulling force of a spring 15 and by an abutment element 16, and a second position
defined by the thrust exerted by a programming actuator, the action of which is schematically
indicated by means of an arrow 27.
[0050] According to the invention, moreover, the engaging lever 7 (Figs. 9 and 10) has its
own seat 30, engaging the locking pin 2c, formed on a rocker 28 mounted pivotably
on the lever 7 by means of a pin 28a. The rocker 28 is kept in a rest position by
a locating element 29 and by a spring 29a.
[0051] In the embodiment shown in Fig. 9, the pivot pin 28a of the rocker coincides with
the rivet 6 of the lever 7. In this case, the locating element 29, which is integral
with the rocker 28, urges, as a result of the action of the spring 29a, against a
tooth 7a formed on the front end 9 of the engaging lever 7.
[0052] In the embodiment of Fig. 10, the pivot pin 28a is arranged instead on the end 9
of the lever 7. In this case the locating element 29 abuts, again as a result of the
action of the spring 29a, against the outer edge of the lever 7.
[0053] The inherent resilient oscillating movement of the rocker 28 ensures that the pin
2c is securely inserted into the seat 30 even in the event of an imprecise approach
movement of the two elements, owing to the rocker 28, on which the seat 30 is formed,
being apt to adapt itself locally around the pin 2c.
[0054] The dobby - in the case of the embodiment according to Figs. 7 to 10 - operates as
follows: at the start of the half-turn of the shaft 1 (Fig. 8) and in the case of
forwards running and programming effected with a view to varying the position of the
frame, the programming device 17 does not exert any action on the lever 14 which,
as a result of the action of the spring 15, comes into abutment against the element
16 and, not causing interference of the end 24b with the lever 7, leaves the latter
subject to the recall action of the spring 12 which keeps the tooth 11 engaged in
the recess 13a.
[0055] In this situation, the eccentric 5 is integrally joined to the rotating disk 13 which,
rotating with the shaft 1 during the half-turn (Fig. 8), draws in rotation the eccentric
5 itself and hence the connecting rod 2 which, oscillating, draws the operating rod
3 of the frame, causing it to change position.
[0056] Before the half-turn has been completed (Fig. 8), the programming device 17 pre-sets
the controlling action relating the next half-turn, namely in the example in question
keeping the frame in the previous position. It does not exert, therefore, any action
on the lever 14, and the end 24a thereof, when it comes into contact (Fig. 7A) with
the surface of the rear end 8 of the engaging lever 7, formed with a rising front
face, forces the lever 7 itself, continuing the rotation of the disk 13, to rotate
about its rivet 6, causing the tooth 11 to come out gradually from the recess 13a
of the disk 13.
[0057] According to the invention, as the lever 7 rotates about its rivet 6 under the action
of the end 24a of the controlling lever 14, the rocker 28 moves towards the pin 2c,
until the latter is received in the seat 30. When small phase-displacement errors
occur in the movement, the possibility of resilient adaptation of the rocker 28 against
the pin 2c ensures that r.o faulty catching of the two elements occurs (something
which could give rise to an irregular escaping movement of the tooth 11 from the recess
13a and to the drawbacks mentioned above) and therefore produces perfect engagement
of the lever 7 with the pin 2c.
[0058] Once the dead centre of the half-turn has been reached (Fig. 7A), the engaging lever
7 is totally rotated outwards and engaged with the pin 2c, while the tooth 11 is totally
extracted from the recess 13a.
[0059] The eccentric 5 thus remains idle with respect to the disk 13 and integrally joined,
by means of the lever 7 and the pin 2c, to the connecting rod 2, this resulting in
the previous position of the heald frame controlled by the rod 3 being maintained
during the next half-turn (Fig. 8A).
[0060] For the sake of brevity, operation has been illustrated referring only to the end
24a of the controlling lever 14, but it is evident that the same type of actuation
may occur at the end 24b of the controlling lever 14, the two ends being apt to disengage
the eccentric 5 from the main shaft 1 each at one of the top dead centre, or bottom
dead centre, of the heald frame.
[0061] A further embodiment of the invention is illustrated in Figs. 11 and 12. Here the
two ends 34a and 34b of the controlling lever are still provided with resiliently
oscillating teeth 34x and 34y, which operate in a manner similar to that of the resiliently
oscillating teeth of the first embodiment of the device (Figs. 2 to 6).
[0062] The oscillating teeth 34x and 34y allow the cam end 8 of the lever 7 to be operated
in an equivalent manner both during forwards running and during reverse running of
the loom. The combination of this structure of the controlling lever 14, which is
able to act gradually and symmetrically on the rear end 8 of the lever 7, with the
oscillating rocker 28, apt to ensure secure locking of the lever 7 with the pin 2c,
improves further the operational reliability of the entire selection device.
[0063] With the device described and illustrated, in fact, the present invention ensures
selection and blocking of the position of the heald frames, avoiding any possible
faulty catching during this stage both during forwards running and during reverse
running of the loom.
[0064] It is understood that other practical embodiments of the invention which are different
from that described and which legitimately fall within the protective scope of the
present invention, as will be obvious to persons skilled in the art, may be possible.
1. Vorrichtung zum Ausführen der Programmierung von Dreh-Dobbys für den Betrieb der Schäfte
in Webmaschinen, von der Art, bei denen die Betätigungshebel (3) der Schäfte durch
Verbindungsstangen (2) betätigt werden, die jeweils an einem exzentrischen Ring (5)
montiert sind, der sich bezüglich der Hauptwelle des Dobbys dreht, wobei der Ring
(5) weiter eine sich mit der Welle (1) drehende Scheibe (13) und einen schwenkbar
auf dem exzentrischen Ring (5) montierten Eingriffshebel (7) aufweist, der mittels
seines Endzahns (11) infolge der Wirkung einer Feder in eine Scheibe (13) eingreifen
kann, wobei die Vorrichtung einen Steuerhebel (14) aufweist, der sich unter der Wirkung
eines Druckmittels (17) und gegen federartige Rückstellmittel (15) um einen ortsfesten
Zapfen (14c) dreht, so dass vorragende Endprofile (14a, 14b) des Steuerhebels, die
alternierend entlang oder außerhalb der Bahn des Endes (8) gegenüberliegend zu dem
gezahnten Ende des Eingriffshebels (7) angeordnet sind, dessen Eingriff in die Drehscheibe
(13) verursachen oder verhindern, wobei das Verschwenken des Steuerhebels (14) während
der Drehung der Hauptwelle ausgeführt wird, und wobei der Eingriffshebel (7) weiter
einen Sitz (20, 30) zum Eingriff mit Stiften (2c) der Verbindungsstange (29) hat,
dadurch gekennzeichnet, dass die beiden vorragenden Endprofile des Steuerhebels (14) mit einem Zahn (14a, 14b;
34a, 34b) versehen sind, der schwenkbar an dem entsprechenden Ende des Hebels (14)
in einer Ausnehmung mit zwei divergierenden Anlageflächen (14x, 14y) montiert ist
und mittels einer Feder (14d) mit einer der Anlageflächen (14x) in Berührung gehalten
wird, so dass er verschwenken kann, bis er mit der äußeren Wand (14y) in Berührung
kommt, um den aktiven Eingriff mit dem Eingriffshebel (7) bei dem Rückwärtslauf des
Dobbys bezüglich der Phase zu verlagern und dass das Druckmittel (17) aus einem einzig
arbeitenden Phasenprogrammieraktuator besteht.
2. Vorrichtung nach Anspruch 1, bei der die Feder, die auf den Eingriffshebel wirkt (7)
und die Feder, die auf die gezahnten Profile (14a, 14b) des Steuerhebels (14) wirkt,
derart dimensioniert sind, dass die Wirkung der erstgenannten nicht von der Wirkung
der letztgenannten übertroffen werden kann.
3. Vorrichtung nach Anspruch 1 oder Anspruch2, bei der der Sitz (30) auf einem sich hin
und her bewegenden Rocker (28) schwenkbar auf einem Ende des Eingriffshebels dem Endzahn
(11) gegenüberliegend montiert ist und der Wirkung einer Feder (29a) unterworfen ist,
wobei der Sitz (30) dazu eingerichtet ist, einen Verrigelungsstift (2c), der mit dem
Körper der Verriegelungsstange (2) einstückig ist, zu ergreifen.
4. Vorrichtung nach Anspruch 3, bei der der Rocker (28) durch die kombinierte Wirkung
einer Feder (291), die zwischen dem Rocker (30) und dem Eingriffshebel (7) wirkt,
und einem Lokalisierungselement (29), das in Berührung mit dem Racd des Eingriffshebels
kommt, in seiner Ruhestellung gehalten wird.
5. Vorrichtung nach Anspruch 4, bei der der Rocker (28) mittels eines Stifts (28a), der
mit der Niet (6) übereinstimmt, schwenkbar auf dem Eingriffshebel (7) zur Drehung
des Hebels selbst auf dem Exzenter (5) montiert ist.
6. Vorrichtung nach Anspruch 4, bei der der Rocker (28) mittels eines Stifts (28a), der
auf dem vorderen Ende (9) des Eingriffshebels angeordnet ist, schwenkbar auf dem Eingriffshebel
(7) montiert ist.