US1945996A - Driving arrangement for shuttles, especially loop shuttles - Google Patents

Description

1934. R. ROSSMANN ,945,

DRIVING ARRANGEMENT FOR SHUTTLES, ESPECIALLY LOOP SHUTTLES Filed March 6, 195].

Fig. 4

Fig. 2 \v Patented Feb. 6, 1934 UNITED STATES PATENT OFFICE DRIVING ARRANGEMENT FOR SHUTTLES, ESPECIALLY LOOP SHUTTLES Application March 6, 1931, Serial No. 520,629, and in Germany March 6, 1930 5 Claims.

The increasing of the efficiency of looms requires continually higher shuttle speeds. It is known that high shuttle speeds can only imperfectly be obtained with the commonly used drivers owing to the rapidly increasing inertia forces. This is particularly the case in loop shuttles which generally have to be thrown through the shed with much higher speed than the shuttles with thread bobbin.

It has been proposed to improve drivers in the sling or whip form by employing a reciprocating slidable element, by which the shuttle is driven. This slidable element is then connected to a connecting rod driven by a crank. For every shuttle shot this crank has to carry out a forward movement, whereupon it returns into its inoperative position until the next following shuttle shot has to be carried out. This improvement has, however, not given favorable results as, together with the slidable element, all other elements have to be accelerated for the shuttle shot, this leading to excessively high bearing pressures and unfavorable conditions of wear. All the elements had to be of unnecessarily large size, so that no better result could be obtained than with the formerly known constructions.

It has further been proposed, to obtain the shuttle shot by pressing the shuttle for a short time against the circumference of a rapidly rotating centrifugal wheel so that the shuttle was carried along by friction. The whole energy necessary for the shuttle shot had to be accumula' ed in the rotating movement of the centrifugal wheel, so that between the several shots the centrifugal wheel, which had been slightly braked at the shot, could gradually resume the normal revolving speed. In this manner it was possible to produce the shuttle shot with much less energy. In spite of repeated attempts it has however been impossible to produce permanently uniform shuttle shots. In order to accelerate to the full shooting speed a shuttle which is at rest, a high pressure is temporarily necessary, which must act upon the shuttle as pushing force and exerts inversely a counter force upon the centrifugal wheel. This pressure can be obtained in the construction mentioned only by friction, wherefor in turn a high pressure is required for pressing the shuttle against the centrifugal wheel. The friciion factors are subjected to disturbances during the operation, for instance becoming soiled or smeared with oil, so that the shuttles then shoot through the shed at irregular or reduced speed. The high friction pressure required further results in very rapid wear of the centrifugal wheel and also of the friction surface on the shuttle, as the centrifugal wheel must, for every shuttle shot, first slightly slide on the shuttle until it draws the same along properly.

The new driving device for shuttles according to the invention admits of any desired high speed of the shuttle, requiring however very moderate energy and excluding wearing of material by friction or sliding, so that it fulfills the object aimed at.

According to the invention a slidable element is employed which is arranged on the shooting point of the shuttle and in the direction of shooting, permanently maintained in rapid reciprocating movement, and which carries out a working stroke after several idle strokes and moves a shuttle in the shooting direction by means of a catch, adapted to be engaged and disengaged, and lets the shuttle fly as soon as the maximum speed has been exceeded during the forward movement. This rapid to and fro movement of the slidable element, the latter being preferably equipped with a pivotable catch pawl, may be produced, in known manner, by a rapidly rotating crank with connecting rod or by a cam disc or by an eccentric.

The shuttle is in this manner of driving uniformly accelerated without jerk, this being very important for the life of the whole arrangement; its starting speed or the speed at which it enters into the shed, setting aside the losses from friction on the travel, being equal to the rotating speed of the crank pin. After the starting of the shuttles the catch pawl is automatically disengaged, whereupon the slidable element moves idly several times to and fro up to the next following shuttle shot.

By suitably selecting the crank length, it is possible to impart any desired maximum speed to the slidable element, which for instance continually alters its speed according to a sinus curve, and this driving arrangement can consequently be very well adapted to the requirements. A second variable value is given by the rotating speed of the crank shaft. It has been found that sometimes such high speeds of rotation are necessary, as are otherwise not usual on looms, so that a considerable transmission to high speed would have to be employed. Where this has to be avoided, it is advisable to provide a separate driving mechanism for the driving crank, which is independent of the usual driving mechanism. According to the invention an individual driving motor is therefore provided in this case, for instance a small electric motor or compressed air motor, which, owing to its facility of regustriking effect, and is brought into engagement lating, permits of an accurate adjusting of the shuttle start.

A form of construction of the new driving arrangement is illustrated by way of example in the accompanying drawing.

Fig. 1 is a diagrammatic view of the new driving arrangement.

Fig. 2 shows the driving arrangement on larger scale in side elevation.

At the shooting point of the loop shuttle a to be moved in horizontal direction and parallel to this shuttle and therefore also in the shooting direction of the shuttle, a guide rod 0 for a sleeve shaped slidable element (1 is mounted in brackets 22, said slidable element d being connected by a connecting rod c with a crank arm f. The a de g of the crank arm 1 is preferably permanently rotated at a high speed by a motor not illustrated. A detent of any suitable shape, for instance as illustrated an oscillatable catch pawl h is mounted on the slidable element (1. This catch pawl comes, in the rear reversing position of the slidable element, into engagement with the shuttle a, for instance by engaging behind a shoulder 2' arranged on the rear end of i the shuttle a. In loop shuttles the thread feeder, designed to bring the thread to the shuttle and not illustrated on the drawing, may be utilized for this purpose, in that, during its forward movement towards the shuttle, it pushes, by means of a push rod k, a striking lever m oscillatable around a pin 1, from the position shown in full lines into the position shown in dash lines in Fig. 2. The pawl h has a downwardly directed finger n, which, when the slidable element (2 is moving backwards, strikes against the forwardly oscillated striking lever m, so that the pawl is raised and engages the shoulder z of the loop shuttle a. During the forward movement of the slidable element 11, which then starts, the shuttle a is also moved forwards. As the speed of the slidable element (1 increases rapidly from the left reversing point up to the middle of its forward stroke, to rapidly decrease again up to the right reversing point or extreme position, the shuttle a. automatically detaches from the slidable element (1, when said shuttle and also the slidable element have reached the maximum speed, the shuttle then flying in the direction of the dash lines 0 (Fig. 1) through the shed not shown. During this operation the pawl h oscillates downwards, so that it assumes at the right reversing position, the position indi- 'cated in dash lines in Fig. 1, the upper arm being horizontal. The pawl h preserves this position also during'the return movement of the slidable element at until, after repeated to and fro movement of the slidable element, it is again raised in the left hand reversing position by with the next following loop shuttle which has again been brought into position.

The engagement of the pawl h may also be derived by suitable connecting levers from the axle g of the crank arm I and even the fresh shuttle assuming the operative position might be utilized for controlling and engaging the pawl h.

Special attention has to be paid in the improved arrangement to the direct lubricating of the driving elements. It has been found that at the necessary high sliding speeds heating occurs on' the slidable element and on the bearing points, unless care has been taken to provide for ample and reliable lubrication. The new driving arrangement is therefore, as far as necessary and in a manner known per se, enclosed in a housing containing an oil bath so that the driving elements are thoroughly lubricated by the oil intensively agitated by the same. In special instances, oil under pressure can be fed in the most important bearing and sliding points in order to ensure absolutely reliable lubrication.

I claim:

1. A shuttle driving arrangement comprising .100 a reciprocable element, a means on said element oscillatable relatively thereto for engaging and driving a shuttle, and means for imparting a reciprocating motion to said element.

2. Ashuttle driving arrangement comprising a base frame, a reciprocable element, a guiding means for said reciprocable element in said base frame, a shuttle resting on said base frame, means on said reciprocable element oscillatable relatively thereto for engaging and driving said shuttle, and means for imparting a reciprocating motion to said element.

3. A shuttle driving device comprising, a reciprocating element, sliding contact means for guiding said reciprocating element adjacent a shuttle, and pivoted means on said element for engaging and driving said shuttle.

4. A shuttle driving device comprising, a shut tle track, a shuttle positioned on said track, a reciprocating element adjacent said track, means for repeatedly reciprocating said element without engaging said shuttle, and means for engaging and driving said shuttle at any desired reciprocation.

5. A shuttle driving device comprising a reciprocating element, sliding contact means for guiding said reciprocating element adjacent a shuttle, pivoted means on said element for en'- gaging and driving said shuttle, and means for oscillating said pivoted means, whereby the shuttle may be engaged with said reciprocating element for driving the same at any one of a plurality of reciprocations.

RUDOLF ROSSMANN.

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