CS198198B2 - Apparatus for guiding main jacquard needles - Google Patents

Abstract

Device for guiding main needles in Jacquard machines having front guide comb, rear resilient frame and a needle operating rake is provided at the rear of the rear frame and in the path of motion of main needles with a presser beam which is reciprocated synchronously with the rake. Sinkers are capable of operation in vibration free manner at speeds >400 rpm.

Description

BACKGROUND OF THE INVENTION The present invention relates to a device for guiding the main needles of a jacquard machine actuated by a pressure comb and intermediate heads of knitting needles with a front guide plate and a rear spring frame.

In known jacquard machines, the main needles are pushed into the spring frame to push the ends of the sinkers out of the path of movement of the sinker knives to move the sinkers from the pressure comb through the heads of the knitting needles against the action of small compression springs. In this case, the main needles are guided by force contact with compression springs arranged on them between the stop and the spring frame. This known design has the disadvantage that erroneous threading of sinkers can occur at very high speeds. The main needles, driven by the pressure comb through the heads of the knitting needles, are at a high speed above 250 rpm. they accelerate so strongly that they push into the spring frame against the action of the compression springs, so that the heads of the knitting needles no longer exert pressure and can fall out of the pressure comb with their point. Thereafter, the main needles associated with the loose heads of the knitting needles are pushed back by means of compression springs, so that even the sinkers controlled by them reach the path of movement of the knives again. Against the information of the student card. (Punched cards) are then lifted into the upper shed even those sinkers that should actually remain in the lower space

Accordingly, it is an object of the invention to provide a device for guiding the main needles in a jacquard machine by means of which it is. . at high revolutions · (above 400 rpm), possible operation of sinkers without oscillation · and · therefore without faults. It is a further object of the invention to overcome the shortcomings of the prior art.

This object is achieved by arranging a thrust beam behind the spring frame in the movement path of the main needles, which performs a reciprocating movement synchronously with the thrust rack.

In a practical embodiment, the thrust beam is movably connected to a curvilinear, force or shape contact drive. The cam drive is expediently provided with a cam disk which bears on a pulley mounted on a lever which, in a forced manner and in synchronism with the thrust rack, performs a reciprocating movement against the action of the compression spring. This curved disk has the advantage that the knitting needle heads and the main needle can be flexibly moved at the beginning of their working stroke by the pressure comb while being forced to be guided between the pressure comb and the pressure beam until The 'thrust beam' at the end of the working stroke did not push the main needles and hence the associated knitting needle heads back exactly to their initial position and also held them therein so that they could not subsequently oscillate.

A noticeable advantage - the main needle guiding devices of the jacquard machine made according to the invention is that there is a forced guiding of the heads of the knitting needles. and the main needles by force and form contact between the pressing comb and the pressing beam, so that it is possible to increase the speed of known jacquard machines from about 200 rpm. to more than 400 rpm without erroneous threading.

Further details and advantages of the subject matter of the invention will become apparent from the following description of the accompanying drawings, in which a jacquard machine with a main needle guiding device constructed according to the invention is shown schematically.

Fig. 1 a diagram of a double - stroke jacquard machine in longitudinal section, and.

FIG. 2 shows the same jacquard machine as seen from the rear.

Control of platinum. 2 of the jacquard machine, connected to the jacquard-brake 1, to move the warp threads (not shown) of the weaving machine, occurs by means of a punch card 3 into which the sliders 4 of the warp stop are threaded. Each rider 4 of the warp stop is connected to a knitting head 5, the Needles, which is connected to the main needle. 8, which acts on the sinker 2. In the illustrated embodiment, the warp stop slider 4 associated with the upper head 5a of the knitting needle was not threaded into. the punch card 3, so that the front end of the head 5a of the knitting needle can be gripped by the pressing pin 7 and moved. In this case, the upper main needle 6a is moved backwards, moving the upper ends of the sinker 2 associated therefrom out of the path of the movements of the blades 8, which are fixed in vertically movable cabinets (not shown). The platinum 2, - assigned to the main needle 6a, therefore remains on the - platinum grate 9 - and forms with its associated warp thread - the lower shed. The warp stop slider 4b associated with the lower knitting needle head 5b, on the other hand, was threaded into the punch card 3, so that the knitting needle head 5b - is not caught at the front end by the crest 7. As a result. 5b of the knitting needle, so that the upper end of the sinker 2, assigned to this main needle 8b, remains standing in the path of movement of the knives 8 and is lifted. The warp threads raised by this sinker 2 then form an upper shed. In simple terms, therefore, the hole in the punch card 3 means that - the main needle 8 is not pushed - - by the pressure comb 7 and thus - the platinum is brought into the upper shed, while the absence of the hole in the punch card 3 causes the needle head 6 and -, platinum 2 in the lower shed.

In a double-jacquard jacquard machine, the pressure comb 7 does not just return, but moves along the curve partly in the direction of arrow I horizontally and partly in the direction of arrow II also vertically, as described, for example, in the 1989 document. pattern.

The main needles 6 are guided at the front end in the guide plate 10 and at the rear end in the spring frame 11. On each main needle 6 a compression spring 12 is provided which abuts one end on the main needle 6 and the other end on the ends of the main needles 6 protruding from the spring frame 11, - are provided with a hook 13, - so that they cannot slip out of the spring frame 11.

Downstream of the spring frame 11 is a pressure beam 14 which is mounted on pins 15 which are guided in bearings 16 which are fastened on both sides of the machine base 17. A pressure spring 18 is provided on each pin 15, which at one end. - abuts - bearing - 16, - and the other end on pin 15.

The movement of the pressure beam 14 is ensured by a curvilinear drive 19, which consists of a cam disk 20, a lever 21 and a roller 22. Thus, the pressure beam 14 can reciprocate against the compression spring 18 in a forced and approximately synchronous manner with the pressure ridge 7.

In the initial position, there is a clearance of about 3.5 mm between the guide rods of the pressure comb 7 and the knitting needle heads 5 so that the warp stopper 4 can be threaded correctly. Once the clearance between the guide rods 7 and the knitting needle heads 5 has been eliminated by the movement of the pressing rack 7, the pressing comb 7 and the pressing beam 14 move synchronously so that the knitting needle heads 5 and the main needles 6 are guided and prevented. further acceleration of the movement of the main needles 6, which is possible with jacquard machines operating at very high speeds, since the guide rods of the pressure comb 7 impact - at high speed - on the heads 5 of the knitting needles and hence on the main needles 6. the pressure beam 17 abuts the hooks 13 of the main needles 6 on the spring frame 11, so that the vibrating or jumping of the main needles 6 is no longer possible during the subsequent threading process. ’

To prevent oscillations of the upper ends of the legs 2a, 2b of the sinkers 2, additional support plates 23 are provided, which are provided at the lower end with an abutment surface 24, which also serves as an anchor. When the main needles 6 and the sinkers 2 are spring back, the oscillations of the arms 2a - 2b are retained by the abutment pad 24. The support plates 23 - with their abutment pads 24 - are arranged in height so that the arms 2a, 2b can rest against the upper part of the support plate 23 if the sinkers 2 are in the lower one

198198 With shed. The legs 2a, 2b of the sinkers 2 are thus secured against adverse oscillations in both directions, thereby also preventing the occurrence of fabric errors.

Claims (3)

OBJECT OF THE INVENTION A device for guiding the main needles of a jacquard machine actuated by a pressing comb and intermediate heads of knitting needles, with a front guide plate and a rear spring frame, characterized in that behind the spring frame (11) is arranged in the path of movement of the main needles (6) a pressure beam (14) which performs a reciprocating movement synchronously with the pressure ridge (7). Device according to claim 1, characterized in that the pressure beam (14) is movably connected to the cam drive (19) by force or form contact. Device according to Claims 1 and 2, characterized in that the cam drive (19) is provided with a cam disk (20) which bears on a roller (22) mounted on a lever (21) which is forced and synchronously with the thrust rack (7). ) is reciprocating against the action of the compression spring (18).