EP1516947B2 - Shaft drive for weaving machines - Google Patents

Description

The invention relates to a switching drive for at least one heald of a loom.

For shedding, a plurality of healds are generally provided on looms, each having a plurality of mutually parallel strands are guided by the thread eyes the warp thread. For shedding the healds are moved up and down very quickly. Serve shaft drives, which are referred to as dobby or eccentric machines. So-called eccentric machines generate from the rotating movement of a drive shaft the up and down movement of the weaves, whereby high weaving speeds can be achieved. However, such eccentric machines are inflexible. The creation of patterns or different bindings is limited. Therefore, shaft drives are widely used, in which a pawl clutch is provided between a drive shaft and the eccentric for generating the shaft movement.

Such a dobby is for example from the DE 697 02 039 T2 known. The pawl shifting mechanism disposed between the eccentric and the driving shaft is here switched on for each shaft movement, ie for an upward movement of the shaft or for a downward movement of the shaft in each case for half a shaft rotation. Such dobby are very flexible. However, such dobby machines can not reach the working speed of eccentric machines. The work of the pawl switching mechanisms is susceptible to wear. An increase in the operating speed, however, not only leads to ratchet wear, but also to strand and shank breaks.

On this basis, it is an object of the invention to provide a shaft drive for the heald of a loom that allows for low load on its elements and the connected heald an increased operating speed.

• Erfindungsgemäß wird die Schaltbewegung nun so festgelegt, dass weder eine reine sinusförmig schwingende Auf- und Abbewegung des Schafts noch eine schwingende Auf- und Abbewegung mit Stillstandszeiten im oberen und im unteren umkehrpunkt erhalten wird. Vielmehr erzwingt der Antrieb nicht nur während der Bewegungsphasen, sondern nunmehr auch während der Ruhephasen des Schafts, in.denen der Schaft ansonsten üblicherweise im oberen oder im unteren Umkehrpunkt ruht, eine fortgesetzte Bewegung desselben. Diese Maßnahme eröffnet die Möglichkeit, die maximalen Beschleunigungen des Schafts zu reduzieren. Die Vermeidung von Beschleunigungssprüngen führt zu einem ruckfreien Lauf der Schäfte, der auch bei hohen Arbeitsgeschwindigkeiten zu keinen übermäßigen Schwingungsanregungen führt.Die Grenze für die Arbeitsgeschwindigkeit, bei der Schaftbrüche und Litzenbrüche auftreten, kann somit sehr weit zu höheren Arbeitsgeschwindigkeiten verschoben werden. Die entsprechenden, von dem Schaft zu durchlaufenden Bewegungskurven können, gemäß einer nicht-erfindungsgemäßen Ausführungsform, mittels frei programmierbarer Antriebe erreicht werden, die den Schaft bewegen. Eine den Antriebe zugeordnete Steuereinrichtung fordert den Antrieben während der Bewegungsphasen eine hohe Geschwindigkeit ab, um den Schaft möglichst schnell aus der einen Umkehrlage in eine andere Umkehrlage zu überführen. Dieser Vorgang ist zur Nachbildung erforderlich, um Kettfäden aus der Kettfadenebene nach oben oder nach unten herauszubewegen. Nähert sich der Schaft seiner anvisierten Umkehrlage, verlangsamt die Steuereinrichtung den Abtrieb des Schaftantriebs, der z.B. durch Verbindungsstangen gebildet ist, und lässt ihn dann bei Erreichen der Umkehrlage um dieselbe pendeln. Je nach Verweilzeit in der Umkehrlage kann die Pendelschwingung ein oder mehrere Maxima und Minima (wellenzüge) durchlaufen. Die Pendelbewegung in den Ruhephasen hat den Vorzug, das der Schaftantrieb Schaftbewegungen vorgerben kann, die geringere Beschleunigungswerte aufweisen. Die Schaftbewegung folgt in ihrem zeitverlauf beim Übergang von einer Umkehrlage in die andere einer harmonischen Funktion (sinus oder cosinus) und geht in der Umkehrlage in eine Zeitfunktion über, zu deren Beginn die Beschleunigung den gleichen wert hat wie beim Verlassen des Kurvenastes der Übergangsbewegung. Der Beschleunigungsverlauf ist somit stetig. Die Bewegungskurven (die auch als "gewegungsgesetze" bezeichnet werden) für den Übergang des Schafts aus einer Umkehrlage in die andere sowie für das Pendeln innerhalb der Umkehrlagenbereiche können bei einer nicht erfindungsgemäßen Ausführungsform in einem Datenspeicher abgespeichert sein. Die Steuereinrichtung ruft dann die jeweiligen Steuerkurven aus dem Datenspeicher auf und steuert den oder die Motoren des Schaftantriebs entsprechend an. Alternativ können die Steuerkurven auch vorab oder in Echtzeit berechnet werden, wobei die Berechnung fallweise abhängig von den jeweils gegebenen Randbedingungen nach speziellen Optimierungskriterien erfolgen kann. Optimierungskriterien können beispielsweise sein, dass eine Mindestfachöffnungszeit nicht unterschritten werden darf, dass die Maximalbeschleunigungen zu begrenzen sind, dass Beschleunigungasprünge unzulässig sind, dass die Schaftgeschwindigkeit zu begrenzen ist oder dass bei gegebener Maximalbeschleunigung eine maximale Arbeitsgeschwindigkeit errechnet wird. Die sich aus diesen Optimierungskriterien ergebenden Kurven können dann zwischengespeichert und zum Ansteuern des Schaftantriebs angewendet werden. Die Pendelbewegung des Schafts im oberen und unteren Umkehrpunktbereich hat den weiteren Vorteil, dass durch die Pendelbewegung des Webschafts die Kettfäden etwas entspannt werden können, was den Schussfadenanschlag erleichtern kann.

This object is achieved with the shaft drive according to claim 1:

• According to the switching movement is now determined so that neither a pure sinusoidal oscillating up and down movement of the shaft nor a swinging up and down movement with downtimes in the upper and lower inversion point is obtained. Rather, the drive forces a continued movement of the shaft not only during the phases of motion, but now also during the resting phases of the shaft, in which the shaft otherwise usually rests in the upper or lower reversal point. This measure opens up the possibility of reducing the maximum acceleration of the shaft. The avoidance of acceleration jumps leads to a jerk-free running of the shafts, which does not lead to excessive vibration excitations even at high operating speeds. The limit for the working speed at which shank fractures and strand breaks occur can thus be shifted very far to higher operating speeds. The corresponding movement curves to be traveled by the shaft can, according to a non-inventive embodiment, be achieved by means of freely programmable drives which move the shaft. A control device associated with the drives requires the drives during the movement phases from a high speed in order to transfer the shaft as quickly as possible from one reversal position to another reversal position. This process is required for replication to move warp threads up or down from the warp thread plane. When the shaft approaches its intended reversal position, the control device slows down the output of the shaft drive, which is formed, for example, by connecting rods, and then lets it oscillate about the same when the reverse position is reached. Depending on the dwell time in the reversal position, the pendulum oscillation can pass through one or more maxima and minima (wave trains). The pendulum motion in the resting phases has the advantage that the shaft drive can pretension shaft movements which have lower acceleration values. The movement of the shaft follows the passage of time from one to another Inverting position into the other of a harmonic function (sine or cosine) and, in the reverse position, changes to a time function at the beginning of which the acceleration has the same value as when leaving the curve branch of the transitional movement. The acceleration curve is thus continuous. The movement curves (which are also referred to as "laws of motion") for the transition of the shaft from one reversal position to the other as well as for the oscillation within the reversal position regions can be stored in a data memory in a non-inventive embodiment. The control device then calls the respective cams from the data memory and controls the one or more motors of the shaft drive accordingly. Alternatively, the cams can also be calculated in advance or in real time, whereby the calculation can be made case by case depending on the given boundary conditions according to special optimization criteria. Optimization criteria can be, for example, that a minimum opening period may not be fallen below, that the maximum accelerations are to be limited, acceleration jumps are inadmissible, that the shaft speed is to be limited or that a maximum working speed is calculated for a given maximum acceleration. The curves resulting from these optimization criteria can then be buffered and applied to drive the shaft drive. The pendulum movement of the shaft in the upper and lower reversal point range has the further advantage that the warp threads can be slightly relaxed by the pendulum motion of the heald, which can facilitate the weft stop.

According to the invention, the movement to be performed by the shaft during the rest phase is generated or predetermined mechanically. The shaft is over a Coupling device optionally connected to a first drive which generates a constantly oscillating between two reversing positions movement, or with another drive which generates the oscillating about the upper or lower reversal position movement. Switching takes place during existing synchronization phases.

The shaft drive according to the invention has an input shaft connected to a rotary drive device, which ultimately serves to drive a gear arrangement which generates the reciprocating movement of the heald shaft. The clutch assembly provided between the input shaft and the transmission assembly has at least two input members and an output member connected to the transmission assembly. The input elements generate at least temporarily a synchronous movement when tapping the movement from the inside. Within these time windows, in which synchronism of the movement tap between both input elements exists and in which the shaft does not rest, the clutch arrangement can switch from one input element to the other input element. The changeover is thus not noticeable as a jolt nor as a shock in the drive train. Reducing the rotational speed of the input shaft is therefore not necessary for switching. It can be achieved without accepting excessive wear or shaft or strand breaks increased operating speed of the loom and even if individually Web shafts must be repeatedly activated and deactivated.

The first input element is a clutch disc that is fixed with the input shaft is connected and thus performs a predetermined by the rotary drive means uniform rotational movement. The second input element is then a clutch disc that performs a rotational oscillation movement. The rotational oscillatory movement is in each case for a short time completely or nearly synchronously with the rotational movement of the first input element in selected angular ranges which correspond to the upper and lower reversal points of the heald. After a short synchronicity, the second input element then rotates back to run in synchronism with the first input element over a certain angular range after a rotation of the first input element through 180 ° again. These short phases of synchronism between both input elements are used to switch a pawl from the first input element to the second or vice versa. When the output member is coupled to the first input member, the stem performs its reciprocating motion. If, however, the output element is coupled to the second, only by a limited angle back and forth swinging Eingazzgselemerit, the shaft is in its resting phase in which he performs only a slight oscillatory movement about its upper and lower reversal point. From this oscillation movement, however, it can be engaged, noting the short synchronizing phases, wherein the acceleration forces and resulting loads on the shaft and the gear elements involved are hardly greater than in the case of uninterrupted operation of the shaft. There are at least none notable jump changes in the acceleration forces.

The oscillating motion of the second input member may be achieved by a cam gear rigidly connected to the input shaft. Preferably, however, a cam drive is used whose shaft is running at twice the input shaft speed, so that both the short synchronous movement for the upper reversal point and the short synchronous movement for the lower reversal point can be generated with a single cam. Alternatively, the oscillating motion can be generated by electrical, hydraulic or pneumatic drives.

As a switching element, a rotating with the output member pawl is used, which is operated via at least one, preferably two shifter, where it passes. The shifters can be directly electrically or pneumatically confirmed. However, it is preferred to drive them via a control clutch from a cam drive ago. The control clutch can then be operated with very low power, on the other hand, sufficiently large forces are generated to move the shift lever. The clutch can e.g. Be controlled by stationary control magnets and be formed by a swinging driven selection finger. This results in a precisely responsive and with low energy controllable control arrangement for the clutch assembly.

In an embodiment not belonging to the invention, the two input elements of the clutch assembly are formed by cams, both of which rotate synchronously with the input shaft and are driven by this. The starting element Here, the coupling arrangement forms a cam follower, which can alternatively be brought into engagement with one or the other cam disk. The cam follower generates a swinging motion and thus is not only part of the clutch assembly but also part of a gear assembly for generating the reciprocating motion from the rotational movement of the input shaft. The switching of the cam follower from the tap of the one cam to the other cam takes place in a rotational position of the cam in which their arcs match, so that the tapped here of the one cam is synchronous with the movement tapped by the other cam disc movement. One of the two cams may be configured to generate the motion required for shedding while the other is constructed as a reversing shim and to generate the oscillating reverse position movement. As such, it only has short synchronizing arches respectively serving to take over the cam follower element and otherwise a profile which does not generate a shedding motion on the weaving sheave but only the reversing position oscillation. In the simplest case, it is a disc with double circumference and lower radial stroke. It is also possible to provide two or more cams with different working profiles. In each case reversing ply disks can be arranged between these cams, which produce the oscillating reversing position movement on the cam follower. Thus, it is possible to switch between cams and neutral pulleys, so that the intercepting cam follower either in engagement with the cam provided with working profile a transitional movement from reverse to reverse or tapping the reversing ply a swinging at a reduced amplitude around or from the reverse position output movement generated.

Furthermore, it is possible to associate each cam set with its cam follower and to couple the cam followers optionally with an output shaft. The cams then form the input elements of the corresponding cam followers, while the output member of the coupling assembly is connected to a linkage which actuates the heald.

Even with such a clutch arrangement can be the switching on and off of the drive of a weaving shaft without slowing down or switching off the rotary drive of the input shaft reach. There is a total or a nearly harmonious movement of the weave not only when weaving, but also when docking and stripping the Webschafts generated. This creates the prerequisite for high weaving speeds with low stress on the machine components involved.

Further details of preferred embodiments of the invention will become apparent from the drawing or the description and claims.

Figur 1

einen Webschaft mit einem nicht erfindungsgemäßen Schaftantrieb in sche- matisierter Darstellung,

Figur 2

den nicht erfindungsgemäßen Schaftantrieb nach Figur 1 in schemati- sierter Darstellung,

Figur 3 und 4

Zeitverläufe der Schaftbewegung und der Schaftbeschleunigung bei unterschiedlichen Schaftbewegungsverläufen in unterschiedli- chen Bewegungsphasen jeweils als Diagramm,

Figur 5

einen nicht erfindungsgemäßen Zeitverlauf der Schaftbewegung

Figur 6

einen webschaft mit erfindungsgemäßem, mechanischem Schaf- tantrieb in schematisierter Darstellung,

Figur 7

Webschäfte und einen zugehörigen Schaf- tantrieb nach Figur 6 in Draufsicht,

Figur 8

den Schaftantrieb nach Figur 6 in aus- schnittsweiser, schematisierter Darstel- lung,

Figur 9

den schaftantrieb nach Figur 8 in einer weiteren schematisierten, ausschnittsweisen Darstellung in einem anderen Maßstab,

Figur 10

den Schaftantrieb nach Figur 8 und 9 in ausschnietsweiser Darstellung,

Figur 11

eine nicht erfindungsgemäße Ausführungsform eines Schaftantriebs mit schaltbaren Kurvenschei- ben in schematisierter Perspektivdarstel- lung,

Figur 12

eine schematische Darstellung des nicht erfindungsgemäßen Schaft- tantriebs mit Kurvenscheiben, in schemati- sierter Darstellung,

Figur 13

eine weitere Ausführungsform eines nicht erfindungsgemäßen mechani- schen Schaftantriebs in teilsweise geschnit- tener Darstellung und

Figur 14

den nicht erfindungsgemäßen Schaftantrieb nach Figur 13 in einer schematisierten Draufsicht.

In the drawings, embodiments of the invention are illustrated. Show it:

FIG. 1

a heald with a shaft drive not in accordance with the invention in a schematized representation,

FIG. 2

the shaft drive not according to the invention FIG. 1 in a schematic representation,

FIGS. 3 and 4

Timing of the shaft movement and the shaft acceleration at different Shaft movements in different phases of movement as a diagram,

FIG. 5

a non-inventive time course of the shaft movement

FIG. 6

a web with inventive, mechanical shaft drive in a schematic representation,

FIG. 7

Heald frames and an associated shaft drive FIG. 6 in plan view,

FIG. 8

the shaft drive after FIG. 6 in a detailed, schematic representation,

FIG. 9

the shaft drive FIG. 8 in a further schematized, fragmentary representation on a different scale,

FIG. 10

the shaft drive after FIG. 8 and 9 in a fragmentary representation,

FIG. 11

1, a non-inventive embodiment of a shaft drive with shiftable camshafts in a schematic perspective view,

FIG. 12

1 is a schematic representation of the non-inventive shaft drive with cams, in a schematic representation,

FIG. 13

a further embodiment of a non-inventive mechanical shaft drive in partially geschnit- tener representation and

FIG. 14

the shaft drive not according to the invention FIG. 13 in a schematic plan view.

In FIG. 1 a heald 1 with associated shaft drive 2 is illustrated. The heald 1 is formed by a provided with strands 95 frame, which is in operation as indicated by an arrow 3 moves up and down. To drive a linkage 4, which attaches to the weaving shank 1 at two or more points 5, 6 and forms the output of the shaft drive 2. The shaft drive 2 includes one or more drive sources, for example in the form of the motors M1, M2. These are, for example, electric servomotors, which are the linkage 4 via a screw jack, a belt transmission or other, the rotational movement of the motors in a linear motion converting gear are connected. Alternatively, linear motors, linear stepping motors or the like can be used. It suffices in some cases, a single engine, while in other two or more engines required are.

The motors M1, M2 are controlled by a control device C, for example based on a microcontroller, which is connected to a memory unit M. The control device C controls the motors M1, M2 in such a way that the heald 1 is moved up and down in accordance with the shed formation. This can be done, for example, by means of two or more curves K1, K2 stored in the memory unit M, wherein the first curve K1 specifies the movement of the heald 1 between its reversal positions, while the curve K2 specifies a movement of the heald 1 in its reversal positions. In detail, the movement of the weave shaft 1 is as follows:

In FIG. 3 is the shaft movement based on the in the direction of arrow 3 in FIG. 1 designated X coordinate of the heald 1 plotted against the time t. The course of the movement is indicated by a curve I, eg the shaft movement can follow a sine function. However, as soon as the stem has reached its upper reversal position TO, in which it could be seen to be woven, the curve I of the movement passes into a vibratory motion of reduced amplitude and reduced acceleration. This marks a curve branch II. The peculiarity of this Kurvenasts is that this in angular ranges of eg ± 15 ° to the upper reversal point TO, the in FIG. 3 indicated sinusoidal oscillation without technically relevant deviation follows. The particular characteristic of the movement impressed on the motors M1, M2 by the control device C is thus that the heald 1 does not rest in the upper reversal point TO but executes a vibration in a reversal point area BTO. The effect of this measure can be seen from the dashed curve III plotted in the same diagram, which illustrates the downward acceleration of the heald 1, which is therefore plotted with negative signs. If the movement of the heald shaft 1 initially follows a sine movement, the shaft acceleration is also a sine function. In the region of the upper vertex, when the upper reversal point TO is reached, the control device C now changes from the curve I to the curve II (FIG. FIG. 2 ). This has almost the shape of a harmonic function, so that the shape of the weaving shaft acceleration in turn is similar to a harmonic function. The movement of the heald I described in its upper dead band BTO by the curved branch II or the curve II is determined so that the acceleration A2 occurring in the upper reversal point TO coincides with the acceleration A1, with that of the heald shaft 1 at the upper reversal point TO arrives.

To illustrate the benefits of Umkehrpunktschwingung in the upper or corresponding at the lower reversal point is on FIG. 3 referenced in which a dot-dash curve branch IV connects the upper vertices of the shaft movement together. If the heald shaft 1 would follow this curve IV after reaching its upper reversal point TO, the acceleration which just has the value A1 would suddenly fall to the value 0 at the time T1. The resulting acceleration peak generated on the weaving shank 1 and the strands and on all associated transmission parts loads that can lead to shaft and strand breaks. Such loads are minimized or largely limited by the pendulum movements, because by the same accelerations are kept to a minimum.
FIG. 4 illustrates that reversal point oscillation can be sustained over several cycles. The rest phase R occurring between the first and the last vertex may extend over one, two or more cycles of the basic oscillation of the shaft movement represented by dashed lines. By fundamental vibration is meant the harmonic function, with which the heald 1 is transferred from its lower reversal point TU to its upper reversal point TO. The latter takes place during its movement phases B.

FIG. 5 FIG. 12 illustrates a modified realization of the above-illustrated idea of imparting low amplitude motion to the heald 1 during its resting phase R, the movement remaining in the upper turning point range BTO or, correspondingly, in a lower turning point range. Again, the vertexes of the prime 1 of the heald 1 illustrated in dashed lines, which serves to transfer from one reversal point to the other, are marked by a curve branch V whose second time derivative has the same acceleration value at times t1, t2 marking the vertices of the fundamental like the fundamental. Thus, the acceleration of the heald 1 is stepless or continuous, as the Kurvenast VI illustrates. However, it will curve according to FIG. 3 or 4 preferred because of the web technical advantages associated with them.

The said movements of the heald shaft 1 in the movement phases B and the resting phases R can also be achieved with a mechanical shaft drive 2, as described in US Pat FIGS. 6 to 10 is illustrated. To the in FIG. 6 illustrated linkage 4 include angle lever 7, 8, which derive the shaft movement of the movement of a pull and push rod 9 and on the one hand to the heald 1 and on the other hand directly or indirectly connected to the pull and push rod 9. This is connected to the shaft drive 2, the output side of a rocker 11, which follows a pivoting movement has. The shaft drive 2 generates from the uniform rotational movement of an input shaft 12 in FIG. 6 illustrated by an arrow 13 reciprocating motion, this movement on the heald 1 as a largely harmonic oscillatory motion in appearance.

As FIG. 7 illustrated, a plurality of heald frames 1, 1a, 1b can be arranged at a small distance one behind the other, which are driven by the common shaft drive 2 and thus by the common input shaft 12. This is connected to a rotary drive device 14, which is formed by a servo motor, another electric motor or an output shaft of a central drive device, which drives other organs of the loom.

The shaft drive 2 ( FIG. 7 ) comprises for each weaving shank 1, 1a, 1b respectively a gear arrangement 15 (15a, 15b) for converting the rotational movement of the input shaft 12 into the reciprocating movement of the respective output side lever 11 (11a, 11b), and a coupling arrangement 16 (16a , 16b), via which the gear assembly 15 is to be selectively connected to the input shaft 12 and to be separated from it. The clutch assembly 16 and the gear assembly 15 are in the FIGS. 8 and 9 schematized illustrated. The coupling arrangement serves to control the movement of the heald and is in this respect the mechanically designed here control device C. The structure ( FIG. 9 ) is as follows:

The gear assembly 15 is formed by an eccentric 17, which via a connecting rod 18, the lever 11 (FIG. Figur7 ) vibrates. The gear assembly 15 thus serves to convert the rotational movement of the eccentric 17 in a reciprocating motion. The eccentric 17 is at the same time the output element of the coupling arrangement 16 (FIG. Figur7 ), to which two input elements in the form of a first disc 21 and a second disc 22 belong. Both discs 21, 22 preferably have the same diameter. However, they can also have different diameters and are designed to improve clarity FIG. 9 also illustrated with different diameters. The first disc 21 is connected to the input shaft 12 and via this to the rotary drive device 14. It thus rotates uniformly at a substantially constant speed. This symbolizes in FIG. 9 an arrow 23. The second disc 22 is rotatably supported about the same axis of rotation 24 as the first disc 21. However, it is not constantly rotating but reciprocating, ie driven rotationally oscillating or drehpendelnd. This is illustrated by arrow 25.

To the clutch assembly 16 from FIG. 7 also includes a switching element 26, shown in FIG FIG. 9 , in the form of a rocker switch 27, which is mounted pivotably about a pin 28 on the eccentric 17. The switching rocker has a first switching nose 29 and a second switching nose 30, wherein the switching lugs 29, 30 are arranged on different sides of the pin 28. The switching lug 29 are assigned to each other by 180 ° opposite recesses 31, 32 in the disc 21. The switching lug 30, however, are assigned to each other by 180 ° opposite recesses 33, 34. By a not further illustrated spring, the rocker switch 27 is biased with its switching nose 29 on the disc 21 out. At its end adjacent the switching nose 31, the rocker switch 27 is provided with a control roller 35, which is thus biased by the spring of the rocker switch 27 with respect to the axis of rotation 24 radially outwardly. The shape of the switching lugs 29, 30 and the recesses 31 to 34 goes out FIG. 10 out. Preferably, the switching lugs 29, 30 and the recesses 31 to 34 are designed so that the engagement and disengagement is facilitated as possible. For this purpose, the switching nose 29 and the front and rear flanks of the recesses 31, 32 are preferably oriented approximately radially. The leading edge of the recesses 31, 32 is slightly lowered against the circumference to facilitate the engagement of the switching lug 29 in the recesses 31, 32. By contrast, the latching recess 33, 34 and the switching nose 30, which is assigned to the reciprocating disc 22, preferably inclined forwardly against the radial. If the latching lug 30 runs against the obliquely set trailing edge of the latching recess 33, 34, the latching lug 30 is pulled into the pane 22. Thus, the switching process is accelerated and executed clearly defined. However, has the latch 29 at least partially found in the recess 31, 32 and commutes the disc 22 back, presses their preferably rounded front edge of the locking lug 30 to the outside and thus completely causes the switching of the rocker switch 27th

In addition, it may be appropriate to perform the switching rocker 27 in two parts, so that the arm 29 carrying the switching nose and the switching nose 30 supporting arm can rotate independently of each other about the pin 28. As a result, during the synchronous phase, in which the disks 21, 22 run synchronously for a short time, both latching lugs 29, 30 can be engaged. The period in which both locking lugs 29, 30 are engaged can and may be greater due to the division of the rocker switch 27 in comparison to the one-piece design. By relieving each disengaged switching lug 29, 30, this can then find out at the appropriate moment from its recess 31, 32 or 33, 34.

The rocker 27 are two levers 36, 37 assigned ( FIG. 9 ), each having a for actuating the control roller 35 serving cylindrically curved button 38, 39. The buttons 38, 39 are approximately concentric with the axis of rotation 24. The shift lever 36, 37, as can FIG. 8 shows, be pivoted radially inwards and outwards. They are pivoted about pivot axes 41, 42. The inner pivot position is selected so that the shift lug 29 is lifted out of its respective latching recess 31, 32 when the control roller 35 runs along the button 38, 39. Accordingly, the switching nose 30 is engaged in the recess 33, 34.

For actuating the shift levers 36, 37 is a cam drive 43 ( FIG. 8 ), which is connected to the input shaft 12 and, for example, has two cams. These are assigned a cam follower lever 44, which is designed as an angle lever and the shift lever 36, 37 is actuated via a selection finger 45, which serves as a control clutch 46. The selection finger 45 is vertically oscillated by the cam follower lever 44 and thus actuates depending on the pivot position either the free end 47 of the shift lever 36 or the free end 48 of the shift lever 37 by the respective end 47, 48 for the time of the deflection of the cam follower lever 44 is pressed down. In order to adjust the pivoting position of the selection finger 45 as desired are on both sides of the same control magnets 51, 52 are arranged, which, when energized, pull the selection finger 45 and hold in this position.
While the disc 21 is constantly driven to rotate, the disc 22, as mentioned, driven rotationally oscillating or drehpendelnd. The purpose of a connected to the disc 22 cam follower 53 ( FIG. 8 ), for example in the form of a roller, which is mounted at the end of a rigidly connected to the disc 22 lever. The cam follower 53 is actuated by a cam 54, for example, rotates at twice the speed of the input shaft 12 and has only a single survey. Thus, the disc 22 receives twice per revolution of the input shaft 12 a reciprocating motion.

The shaft drive 2 described so far operates as follows ( FIG. 9 ):

It is initially assumed that the eccentric 17 is to rotate constantly. For this purpose, the rocker switch 27 must constantly connect the disc 21 with the eccentric 17. To achieve this, each of the shift lever 36 and the shift lever 37 must always escape to the outside when the rocker switch 27 passes as a result of the rotation of the disc 21 to the respective shift lever. For this purpose, the control magnets 51, 52 are alternately driven so that the selection finger 45 pushes the end 47 down when the rocker switch 27 passes by the shift lever 36 and that the selection finger 45 pushes the end 48 down when the rocker switch 27 on the shift lever 37 passes.

The buttons 38, 39 of the shift levers 36, 37 extend over an angular range, which can be regarded as a shift range. The cam follower 53, together with the cam 54, a pendulum drive 55. This imparts the disc 22 to a rotary pendulum motion, which is always synchronous with the movement of the disc 21 when the rocker switch 27 passes through the switching areas. These movement phases are characterized in that the cams of the cam drive 43 urge the end of the cam follower lever 44 to the outside.

During the phase of the synchronous running of the discs 21, 22, the clutch assembly 16 can be switched by the respective shift lever 36 or 37 does not escape to the outside. This will ( FIG. 9 ), for example, the switching lug 29 pushed out of the recess 31 and the switching lug 30 engaged in the recess 33. The relevant shift lever 36 or 37 then remains activated by the relevant shift lever 36, 37, for example by springs 56, 57 (FIG. FIG. 8 ) is held in its inner position and is not moved outwardly by the selection finger 45. The eccentric 17 performs only a reciprocating motion in this state, because he is bound to the disc 22. The movement oscillating back and forth by a few degrees, for example 10 °, causes only a slight upward and downward movement of the same in the upper or lower reversal point of the heald, at most only a few millimeters. This does not disturb the shedding and weaving process. However, it allows a synchronous reconnection by only the relevant lever 36, 37, in which the rocker switch 27 is pivoted outwardly. The cam drive 43 causes this at the moment of synchronization of the two discs 21, 22, so that a soft shock-free restart of the eccentric 17 takes place.

By the above-explained interplay of the coupling assembly 16 of the heald 1 receives the course of motion according to FIG. 3 or FIG. 4 , In each case at the apex of the basic vibration illustrated by dashed lines is switched between rest periods and movement phases. Either follows the eccentric of the continuous disc 21 (movement phase) or the oscillating disc 22 (resting phase). Accordingly, either the sinusoidal positioning movement from TU to TO or TO to TU through (movement phase) or it will pass through the rest phase R, in which the pendulum motion is traversed according to curve branch II. Switching takes place during a synchronous phase S (-15 ° to + 15 ° about the vertex of the movement curve B of the movement phase B), in which the oscillations of the movement phase B and the rest phase R are sufficiently synchronous.

A modified embodiment of the shaft drive 2 goes out FIG. 11 out. The input shaft 12 is here provided with a profile toothing and carries a plurality of cams 61, 62, 63 existing disk package. The cam disks 61, 62, 63 form the input elements of the clutch assembly 16. The output member is here formed by a cam follower element which scans the outer periphery of one of the cams 61, 62, 63. This purpose, a roller 64 which is rotatably mounted at one end of a rocker 65. The role is thus at the same time on the one hand output element of the clutch assembly 16 as well as on the other hand gear assembly 15 for converting the rotational movement of the shaft 12 in a reciprocating motion. The other end of the rocker 65 is connected via the connecting rod 18 with the lever 11 in order to give this a pivoting movement. A fluid cylinder 66 may also serve to continually bias the roller 64 against the cams 61, 62, 63.

The cams 61, 62, 63 are axially displaceable as a package on the profiled input shaft 12 stored. For displacement serves a control fork 67 and one of these associated, only schematically illustrated linear actuator 68th

The cams 61, 62, 63 have, as for example FIG. 12 Obviously, different circumferential profiles. For example, the cams 61 and 63 may be formed as neutral discs, which specify the reversal point vibration in the upper and in the lower reversal point. Are they active, ie rolls off the roller 64 at its periphery, performs the rocker 65 a pivoting movement, so that the weave around its reversal point, for example, with double frequency in relation to the fundamental oscillates (range R from FIG. 3 ). At least one of the adjacent disks 61, 62, 63 has an outer circumference serving as a working profile. This is in the present embodiment, between the discs 61, 63 arranged disc 62. It has a working profile, which leads from an inner minimum diameter R1 to a maximum diameter R2 and back from this. If the roller 64 follows its profile, the shaft performs a working movement (area B) FIG. 3 ). In each case relatively small synchronous angular ranges S1, S2, the circumferential profile coincides in each case with the profile of the cam disk 61 or 63. The cam 61 is formed as a neutral disc which causes the heald to oscillate at a turning point when the roller 64 runs on its circumference. On the other hand, the cam 63 causes the heald to oscillate at the other reversal point as the roller passes along it. In the synchronous angular ranges S1, S2, the package consisting of the cams 61, 62, 63 can be displaced axially in order to engage the roller 64 with the adjacent camming disk 61 or 63. In this way, the movement of the lever 11 within the synchronous areas S1, S2 can be switched on and off smoothly. As in the embodiment described above, the switching on and off of the drive is also based here on the fact that the switching over from one input element to another occurs during a short synchronous phase. In the embodiment according to FIG. 11 the synchronism refers to the radial component of movement of the roller 64 while in the embodiment according to FIGS. 6 to 10 refers to the rotational movement of the discs 21, 22.

In the Figures 13 and 14 is a modified embodiment of the switchable cam drive illustrated, which manages without sliding curves. As FIG. 14 Illustratively, the cam drive includes a total of four cams 60, 61, 62, 63, wherein, for example, the cams 60 and 62, the in FIGS. 3, 4 and 5 each identified by dashed lines fundamental vibrations for transferring the heald 1 from a reversal position in the other mark while the cams 61, 63 set the vibration in the upper or in the lower reversing point. The use of four cams 60, 61, 62, 63 makes it possible to offset the up and down movement of a heald 1 in time. For this purpose, the heald 1, after it has been moved by means of the cam 60 in the upper reversal point, transferred by means of the cam 61 in a pendulum motion, from which it is then transferred by the cam 62 down to the lower reversal point. This equals a phase shift of 180 degrees. Each cam 60 to 63 is in each case with a cam follower 71, 72, 73, 74 in connection. FIG. 13 illustrates the cam follower 74, which scans the outer circumference of the cam 63 with two rollers 75, 76.

The cam followers 71, 72, 73, 74 are pivotally mounted on a rotatably mounted shaft 77 which actuates the rocker 11 via a lever 78 and a link 79. The shaft 77 may be formed as a hollow shaft and accommodate the clutch assembly 16, which is rotatably connected to the shaft 77 selectively one of the cam follower 71, 72, 73, 74. To the clutch assembly 16 then here a shaft 16 passing through cylindrical body 81 which is provided for each cam follower 71 to 74 each having a radially oriented fluid channel 82. In this sitting piston 83, 84, whose flattened part-cylindrical heads for actuating clutch rollers 85, 86 are used. These sit in radial bores of the hollow shaft 77 and can be pressed by the piston 83, 84 to the outside. They engage in corresponding recesses 87, 88 of the respective cam follower 71 to 74. By means of corresponding selectively accessible radial connections 91, 92, 93, 94 (FIG. FIG. 14 ), the pistons 83, 84 of each cam follower 71 to 74 can be specifically controlled separately, to couple only one of the cam follower 71 to 74 with the hollow shaft 77. In this way, one of the predetermined by the cams 60, 61, 62, 63 motion profiles can be selected, wherein the switching in each case in the synchronization phases according to FIGS. 3 to 5 he follows.

A novel shaft gear for harmonic switching on and off of individual healds and for deriving their movement from the rotational movement of a single input shaft has a coupling arrangement with two input elements 21, 22, 61, 62. While one of the input elements serves to permanently drive the output member of the clutch assembly 16, the other input member 22, 62 merely serves to briefly synchronize the output member 17 and 64, respectively, to the first input member 21, 61. Switching takes place in the short synchronization phases in selected angular ranges corresponding to the upper or lower reversal point of the heald. Such new shaft drives do not require a catch of the input shaft or the shaft drive for switching.

LIST OF REFERENCE NUMBERS

1, 1a, 1b

heald

95

braid

2

shaft drive

3

arrow

4

Downforce (e.g., linkage)

5, 6

Put

7, 8

bell crank

9

Pull and push rod

11

wing

12

input shaft

13

arrow

14

Drehantreibseinrichtung

15

transmission assembly

16

clutch assembly

17

eccentric

18

pleuel

21, 22

Input element / disc

23

arrow

24

axis of rotation

25

arrow

26

switching element

27

rocker

28

spigot

29, 30

switching tabs

31, 32, 33, 34

recesses

35

control roller

36, 37

gear lever

38, 39

button

41, 42

swivel axis

43

cam drive

44

Cam follower lever

45

selection finger

46

control clutch

47, 48

The End

51, 52

control magnets

53

cam follower

54

cam

55

pendulum drive

56, 57

feathers

60, 61, 62, 63

Input element / cams

64

role

65

seesaw

66

fluid cylinder

67

control fork

68

actuator

71, 72, 73, 74

cam follower

75, 76

roll

77

wave

78

lever

79

handlebars

81

body

82

fluid channel

83, 83

piston

85, 86

clutch rollers

87, 88

recesses

91, 92, 93, 94

connections

A1, A2

acceleration

B

movement phases

C

control device

K1, K2

curves

M

storage unit

M1, M2

Engines

T0, TU

Reverse position, reversal point

BTO

Reversal point range

t

Time

R

dormancy

R1, R2

radii

S

synchronous phase

S1, S2

synchronous areas

ω1, ω2

angular frequency

Claims (6)

1. Shaft drive for at least one heald shaft (1) of a weaving machine,
   with at least one output (4) associated with the heald shaft (1) and connected thereto in order to hold this in resting phases (R) and impart an adjusting movement corresponding to a harmonic function from a lower return point (TU) into an upper return point (TO) in movement phases (B),
   with a control means (C, 16) for controlling the current speed of the output (4) and thus the heald shaft (1),
   wherein outside the movement phases (B) the output (4) to the heald shaft (1) also performs a predefined continued oscillating movement during the resting phases (R) in an upper return point region (BTO) or in a lower return point region (BTU),
   wherein at the beginning of a resting phase (R) the output (4) has an acceleration, which matches its acceleration at the end of the preceding movement phase (B), and also at the beginning of a movement phase (B) has an acceleration, which matches its acceleration at the end of the preceding resting phase (R),
   wherein acceleration surges [are] avoided and a jolt-free operation of the heald shaft (1) is predefined,
   wherein the drive (2) has a coupling arrangement (16), which is arranged between a drive means (14) and a gear arrangement (15) for transfer of the drive movement to the heald shaft (1), wherein the coupling arrangement (16) has a first input element (21) connected to the drive arrangement (14) and a second input element (22) as well as an output element (17), which is to be selectively connected to the first input element (21) during the movement phase (B) or to the second input element (22) during the resting phase (R), wherein the drive means (14) imparts a movement with constant direction of movement to the first input element (21) and wherein a movement with changing direction of movement is impressed on the second input element (22),
   wherein the output element is formed by a cam (17), the first input element is formed by a first disc (21) and the second input element is formed by a second disc (22), wherein the first disc (21) is connected to the drive means (14) by an input shaft (12) and is driven to constantly rotate, and the second disc (22) is mounted to be rotatable around the same rotational axis (24) as the first disc (21) and is driven to rotationally oscillate,
   wherein the coupling arrangement (16) includes means (36, 37, 46, 44, 43) with a shift member (26), which is to be connected permanently to the output element (17) and selectively to the first or the second input element (21, 22), wherein the shift member (26) is a shift rocker (27), which is disposed on the cam (17) to pivot around a journal (28),
   and wherein the first disc (21) and the second disc (22) are driven synchronously during a synchronous phase and the switchover is performed during the synchronous phase.
2. Shaft drive according to claim 1, characterised in that the predefined movement of the resting phases is determined by the control means (C, 16).
3. Shaft drive according to claim 1, characterised in that the rotational-oscillating movement of the second disc (22) at shift positions predefined by the means (36, 37, 46, 44, 43) is synchronous with the rotational movement of the first input element (21), and
   that the means (36, 37, 46, 44, 43) include at least one shift lever (36, 37), which is associated with the shift rocker (27) in order to engage or disengage this at at least one predefined shift position.
4. Shaft drive according to claim 3, characterised in that the shift rocker (27) rotates with the output element (17).
5. Shaft drive according to claim 4, characterised in that the shift rocker (27) respectively has at least one positive-locking element (29, 30) for each input element (21, 22).
6. Shaft drive according to claim 3, characterised in that the shift lever (36, 37) is connected to a cam drive (43) by means of a control coupling (46), that the control coupling (46) has a selector finger (45), which is adjustably disposed between at least two positions to activate and deactivate the operation of the shift lever (36, 37) by the cam drive (43), and that the selector finger (45) is movable by means of at least one control magnet (51, 52).

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