EP0402587B1 - Knitting tool for knitting machines - Google Patents

Description

The invention relates to a knitting tool, for example a selection board or a needle for knitting machines, with a flat shaft part and with a narrow, elongated control spring which projects in the area of a narrow side of the shaft part and which has an end part in a slot-like opening that opens towards this narrow side Opening is inserted on the shaft part and is rigidly anchored to the shaft part.

For example, DE-A 1585 211 describes a circular knitting machine with electronic needle selection, in which the needles are shaped by pushers are controlled by selection boards which can be swiveled radially back and forth in a pattern between an effective and an ineffective position, in order to bring them into and out of engagement with a stroke curve. In the area of a narrow side, each of these selection boards carries a cantilevered control spring in the manner of a spring rod, which is anchored at one end to a shaft part of the selection board. This control spring is supported in the area of its free end against an abutment on the needle cylinder and acts as a return spring for the electromagnetically controlled selection board.

To anchor the control spring to the shaft part of the selection board, an end part of the control spring is bent approximately in a hairpin shape and pressed with one leg into a slot-like opening in the shaft part that widens at the end.

Since the control spring is thus only clamped with its end part in the slot-like opening in the shaft part of the selection board and is thus held in a frictional manner under pretension, there is a risk that the end part will result from the slot-like opening in the shaft part due to the high dynamic loading of the control spring Selection board works out a little laterally, with the result that additional friction occurs in the associated guide channel of the needle and the selection board, which is undesirable. Uncontrolled dimensional changes in the position of the control spring relative to the selection board can also occasionally occur, which likewise impair the function of the knitting machine.

Basically, the same also applies to a selection board known from US-A-3643 472 (FIG. 10), the control spring of which is clamped with its end part in an opening running approximately at right angles to the longitudinal axis of the board and parallel to the side, and is secured in the axial direction thereof by an end piece bent at right angles is. The board must be formed with an essentially L-shaped, slot-like opening, which is not easy to manufacture.

Finally, from DE-A-2327 585 a circular knitting machine is known which works with needles, each of which carries on its shaft part a control spring which is anchored on one side and serves for magnetic needle selection. The arrangement is such that the control spring made of steel wire of round or slightly flat-rolled, i.e. flattened cross-sectional shape or punched out of thin spring steel sheet is fitted with its end part in a parallel-flanked slot on the needle shaft part and is fixed therein by caulking. In this way, a positive connection is produced between the end of the control spring and the needle shaft part, but the individual embossing points arranged at a distance from one another in the region of the side walls of the slot do not ensure a precise lateral alignment of the control spring with the needle shaft. Since the end part of the control spring is hardened and is therefore not deformed when caulking, it cannot be ruled out with certainty that the end part of the cantilever will change over time due to the high dynamic loading of the control spring something free working, with which the entire control spring would be limitedly rotatable at its anchoring point. There is also the risk that the slot is widened by the transverse forces occurring during the caulking and thereby the upright dimension of the shaft is changed in an uncontrollable manner.

Based on this prior art, the invention has for its object to provide a knitting tool provided with a control spring anchored on one side, which is characterized by an anti-twist, exact and secure anchoring of the control spring to the shaft part over long operating periods even under high dynamic stress, without to affect the economic viability of the manufacturing possibilities.

To achieve this object, the knitting tool mentioned at the outset is characterized in that a recess is formed in the shaft part following the opening, the width of which is measured transversely to the longitudinal extent of the opening, at least in places greater than the width of the opening, that the control spring is on its end part has a widened anchoring section corresponding to the width of the depression, the thickness of which is less than or equal to the depth of the depression and that the control spring is guided laterally in the opening at least on one side and is fitted with its anchoring section into the depression.

The position of the opening and the recess ensures an exact alignment in the respectively predetermined position. Since the recess is wider than the opening, the control spring is widened in the longitudinal direction by its Anchoring section locked in a form-fitting manner. At the same time, the widened anchoring section prevents the control spring from being rotated unintentionally. Finally, there is a very precisely correct mounting option for the control spring, because the recess ensures a clear, fixed assignment of control springs and shaft part. This also makes it possible to direct the control spring in a targeted manner, should this be expedient in individual cases. The control spring can be assembled by the manufacturer, whereby - if necessary - different control springs can be attached to the shaft part without modification.

In a preferred embodiment, the depression has an essentially flat bottom surface, to which a corresponding, at least partially flat support surface on the anchoring section is assigned. The groove-like recess and the anchoring section can each be formed with parallel side walls, which considerably simplifies the manufacturing and assembly conditions. In particular with regard to the production, the depression can advantageously also be arranged in the extension of the straight opening and symmetrically to its longitudinal axis, but in principle, of course, embodiments are conceivable in which the depression is provided, for example, at an angle to the axis of the straight opening is. For the recess itself, designs that deviate from the groove shape can also be selected, for example a circular shape, to mention only one other possibility.

The anchoring section is generally arranged in a recessed manner on the end part of the control spring with respect to only one side surface of the end part, and it can be formed in a simple manner by pressing off the end part of the control spring. In a preferred embodiment, the depth of the depression and the thickness of the anchoring section are approximately equal to half the thickness of the shaft part; depending on the stress conditions etc., a different dimensioning of the depth or thickness is also possible.

The depression can advantageously be connected to the opening via beveled or rounded shoulders, which facilitates the fitting and prevents sharp edges.

The control spring is guided laterally in the opening on both sides when it is important to firmly clamp the end part of the control spring over a certain length on both sides. However, there are also selection boards or needles for which a lower bending stiffness of the control spring is desired in the area of its clamping point. For example, in such cases, the opening, starting from its opening towards the narrow side of the shaft part, can be laterally set back with a side wall with respect to the control spring over a predetermined length section. If necessary, this laterally recessed length section can extend as far as the depression itself. The side wall of the opening then only causes the control spring to be guided on one side.

In principle, it is conceivable to have the control spring on your To connect the end part to the shaft part only in that the end part or anchoring section is prestressed into the opening or the depression and held there by friction. This may even make an interchangeable arrangement of the control spring on the shaft part possible. Appropriately, the control spring is firmly connected at its end part to the shaft part, which can advantageously be done in such a way that the anchoring section is welded or soldered to the shaft part, glued or attached to it in a form-fitting manner, for example by caulking.

The knitting tools to which a control spring can be attached in the manner described include needles, sinkers, pushers etc., in short all parts which serve to form or cooperate with stitches and which must be equipped with such a control spring.

Fig. 1

ein Strickwerkzeug gemäß der Erfindung, in Gestalt einer Auswahlplatine, in einer Seitenansicht,

Fig. 2

das Endteil mit dem verbreiterten Verankerungsabschnitt der Steuerfeder des Strickwerkzeugs nach Fig. 1, in einer Draufsicht, im Ausschnitt und in einem anderen Maßstab,

Fig. 3

die Steuerfeder des Strickwerkzeugs nach Fig. 1, geschnitten längs der Linie III-III der Fig. 1 und in einem anderen Maßstab,

Fig. 4

das Schaftteil des Strickwerkzeugs nach Fig. 1, im Ausschnitt, unter Veranschaulichung der Befestigung der Steuerfeder und in einem anderen Maßstab,

Fig. 5

die Anordnung nach Fig. 4, geschnitten längs der Linie V-V, im Ausschnitt und in einem anderen Maßstab,

Fig. 6

die Anordnung nach Fig. 4, geschnitten längs der Linie VI-VI der Fig. 4, im Ausschnitt und in einem anderen Maßstab,

Fig. 7

ein Strickwerkzeug gemäß der Erfindung, in Gestalt einer zweiten Ausführungsform einer Auswahlplatine, in einer Seitenansicht und im Ausschnitt, und

Fig. 8

das Strickwerkzeug nach Fig. 7, geschnitten längs der Linie VIII-VIII, im Ausschnitt und in einem anderen Maßstab.

Exemplary embodiments of the subject matter of the invention are shown in the drawing. Show it:

Fig. 1

a knitting tool according to the invention, in the form of a selection board, in a side view,

Fig. 2

the end part with the widened anchoring section of the control spring of the knitting tool according to FIG. 1, in a plan view, in the cutout and on a different scale,

Fig. 3

1, cut along the line III-III of FIG. 1 and on a different scale,

Fig. 4

1, in the cutout, illustrating the attachment of the control spring and on a different scale,

Fig. 5

4, cut along the line VV, in the detail and on a different scale,

Fig. 6

4, cut along the line VI-VI of FIG. 4, in detail and on a different scale,

Fig. 7

a knitting tool according to the invention, in the form of a second embodiment of a selection board, in a side view and in detail, and

Fig. 8

7, cut along the line VIII-VIII, in the cutout and on a different scale.

The knitting tool shown in FIGS. 1 and 7 in two embodiments is a so-called selection board for a circular knitting machine with electromagnetic needle selection, as described, for example, in DE-PS 37 12 673. Apart from elements of no further interest here, the selection board has a shaft part 1 on which a control foot 2 is seated and via which the selection board, when inserted into the machine, on the narrow side opposite the control foot 2 at a pivot point 3 on the floor indicated at 4 the associated guide groove is pivotally supported on the needle or sinker cylinder.

In the narrow side opposite the control foot 2, a narrow, elongated control spring 5 is cantilevered at one end on the shaft part 1, the width of which essentially corresponds to the thickness of the shaft part 1 punched out of sheet steel and which is aligned parallel to the shaft part 1. The control spring 5 in the embodiment according to FIGS. 1 to 6 consists of a round wire made of spring steel flattened on both sides at 6 (FIG. 3); it is slightly rounded at its free end at 7 and lies in the assembled state of the selection board on the bottom 4 of the guide groove. The shaft part 1 is provided in the area of the control spring 5 on its underside with an edge-open recess 8 into which the control spring 5 projects and into which the control spring 5 can be inserted when the selection board is pivoted or tilted, as indicated by the broken line in FIG. 1 is.

The control spring 5 is rigidly anchored to the shaft part 1 in the region of the recess 8 with its end part 9, the shape of which is shown in detail in FIGS. 2, 3 and 6. The end part 9 has a widened anchoring section 10 at the end, which is arranged symmetrically to the longitudinal center plane of the control spring 5 indicated at 11 and was produced by correspondingly pressing the spring steel wire forming the control spring 5 on one side. The anchoring section 10, which is essentially parallel-flanked at 12, is, as can be seen from FIGS. 3.5, recessed only with respect to one side surface 6 of the end part 9, while on its other side it is flush with the associated side surface 6 and thus a flat contact surface 13 forms. The two substantially straight side surfaces 12 of the anchoring section 10 finally merge at 14 into the two side surfaces 6 of the end part 9.

In the shaft part 1, on the lower narrow side towards the recess 8, a slot-like opening 15 with a parallel flank is formed, which is followed by a parallel-flanked groove-like recess 16 in the straight extension of its longitudinal axis, which extends from a broad side into the shaft part 1 is milled. The slot-like opening 15 has rounded edges at the transition into the recess 8 at 17, 18. Their width corresponds to the thickness of the end part 9 of the control spring 5, which thickness is measured at right angles to the surfaces 6 (FIG. 3). The depression 16 is then connected to a curved cutter outlet section 170 over most of it their length at 180 formed with a flat bottom surface that extends symmetrically on both sides to its central axis. The depth 19 of the recess 16, like the thickness 20 of the anchoring section 10, is in each case approximately half the thickness of the flat shaft part 1.

In the assembled state, the control spring 5 with its flat anchoring section 10 is fitted into the recess 16 in the manner particularly shown in FIGS. 1.4, while the region of the end part 9 adjoining the anchoring section 10 in the slot-like opening 15 is also tightly tolerated is included, such that it is guided on both sides of the opening 15 without play. The recess 16 is formed in its outline shape of the contour of the anchoring section 10 including its beveled transitions at 14, so that by interacting with the resulting shoulders 21, which run in a wedge shape at an acute angle 22, an exact axial locking of the anchoring section 10 and so that the control spring 5 is ensured on the shaft part 1. Since the anchoring section 10, starting from a surface 6 of the control spring 5, is pressed, the end part 9 lies symmetrically in the center of the opening 15, while on the two opposite broad sides of the shaft part 1 there are no projecting surface parts, as is evident from FIG. 5 shows.

In the recess 16, the anchoring section 10 is positively fixed by edge-side caulking 23, for which reference is made to FIG. 6.

Instead of or in addition to the caulking 23, the anchoring section 10 located in the recess 16 could also be fastened to the shaft part 1 by soldering or welding. Embodiments are also conceivable in which such attachment by means of caulking, welding, soldering etc. is dispensed with and the anchoring section 10 is only pressed into the recess 16 with a slight excess, so that there is a frictional fixation under pretension.

In the embodiment according to FIG. 7, the same parts as in the described embodiment according to FIGS. 1 to 6 are designated by the same reference numerals, so that a further explanation is unnecessary in this respect.

In contrast to the embodiment according to FIGS. 1 to 6, the control spring 5 is designed here as a flat profile, as is indicated by the cross-sectional illustration at 24. The control spring 5 is attached at one end to the shaft part 1 in such a way that it is aligned with its two broad sides 60 parallel to the adjacent narrow side of the shaft part 1. The slot-like opening 15 is wider than the control spring 5, such that its side wall 25, which is remote from the upper edge of the shaft part 1, is set back with respect to the control spring 5. The control spring 5 is supported, moreover, on the opposite side wall 26 and is guided thereon in accordance with its bending line.

The laterally recessed length section of the one side wall 25 of the opening 15 extends up to the groove-like recess 16, the depth 19 of which in this case is greater than half the thickness of the shaft part 1. The pressed, widened anchoring section 10 on the end part 9 of the control spring 5 8, as seen from FIG. 8, arranged recessed from both broad sides, its thickness 20 in this case being smaller than the depth 19 of the recess 16. The anchoring section 10 is again fixed in the recess 16 by caulking 23. The control spring 5 is locked in the longitudinal direction of the recess 16 by the shape of the side wall 26, which cooperates with a corresponding curvature of the control spring 5. The anchoring section 10 is also limited laterally parallel flanks. Its contact surface 180 is flat, which also applies to the same extent for the part of the base surface 13 of the depression 16 that is used.

The control spring 5 can be seen in the direction of loading as a profile spring tongue; a corresponding design of the control spring 5 could also be selected in the embodiment according to FIGS. 1 to 6.

In the two described embodiments, the recess 16 is in each case formed by a groove-like cutout in the shaft part 1. As an alternative, embodiments are also conceivable in which the depression is made, for example, circular in the form of a blind hole or with another corresponding outline design. The anchoring section 10 is in any case designed according to the outline shape of the recess 16 so that it can be fitted tightly. It must be ensured that the recess 16 and the anchoring section 10 are at least in some places wider than the opening 15 in such a way that a positive locking in the direction of the longitudinal extent due to the differences in width between. the opening 15 and the recess 16 is ensured. The widened anchoring section 10 generally has an approximately rectangular cross-sectional shape. It could be, for example, pointing towards the bottom of the depression but also crowned or different.

Claims (14)

1. Knitting tool, for example a selector sinker or needle for knitting machines, comprising a flat shank and a narrow elongated control spring projecting in the area of a narrow side of said shank, said control spring being inserted at one end into a slot-like opening on said shank, which opens towards its narrow side and is rigidly anchored therein, characterised in that a recess (16) is formed in said shank (1) to adjoin said opening (15), said recess (16) having a width, measured in transverse direction of the longitudinal extension of said opening (15), which is greater, at least at some locations, than the width of said opening (15); that said control spring (5) has an end section (9) provided with an anchorage section (10), which broadens to correspond to the width of said recess (16), the thickness (20) of said anchorage section (10) being less than or equal to the depth (19) of said recess (16); and that said control spring (5) is laterally guided in said opening (15) on at least one side and is fitted into said recess (16) by its anchorage section (10).
2. Knitting tool according to Claim 1, characterised in that the recess (16) has a substantially plane bottom face (180), which corresponds to a respective contact surface (13) with at least some plane regions on the anchorage section (10).
3. Knitting tool according to Claim 1 or 2,
   characterised in that the groove-like recess (16) and the anchorage section (10) are each provided with parallel side surfaces (12).
4. Knitting tool according to one of the preceding claims, characterised in that the recess (16) is disposed in the extension to the linear opening (15) and arranged symmetrically with respect to the longitudinal axis thereof.
5. Knitting tool according to one of the preceding claims, characterised in that on the end section (9) of the control spring (5), the anchorage section (10) is recessed relative to only one side face (6) of said end section (9).
6. Knitting tool according to Claim 5, characterised in that the anchorage section (10) is formed by pressing the end section (9) of the control spring (5).
7. Knitting tool according to one of the preceding claims, characterised in that the recess (16) adjoins the opening (15) via sloped or rounded lateral shoulders (21).
8. Knitting tool according to one of the preceding claims, characterised in that, beginning at its opening towards the narrow side of the shank (1), the opening (15) is laterally set back relative to the control spring over a predetermined length section at one side surface (25).
9. Knitting tool according to Claim 8, characterised in that the laterally set back length section extends to the recess (16).
10. Knitting tool according to one of the preceding claims, characterised in that the anchorage section (10) is non-releasably fastened to the shank (1).
11. Knitting tool according to Claim 10, characterised in that the anchorage section (10) is welded, soldered or glued to the shank (1).
12. Knitting tool according to Claim 10, characterised in that the anchorage section (10) is fastened to the shank in form-locking manner, e.g. by means or wedging.
13. Knitting tool according to one of the preceding claims, characterised in that the depth (19) of the recess (16) and the thickness (20) of the anchorage section (10) are approximately equal to half the thickness of the shank (1).
14. Knitting tool according to one of the preceding claims, characterised in that the control spring (5) is in the form of a flat spring tongue in the direction of load application.

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