ELECTROMAGNETIC SELECTOR DEVICE IN KNITTING MACHINE

Abstract: An electromagnetic selector device in which a selector is supported by a carriage so that an attractive select face (30) of the selector moves along and in sliding contact with an upper edge of each of thin plate-like select jacks supported rockably by a support jack through a support member, the attractive select face of the selector being provided with a jack posture correcting edge (A) projecting from the attractive select face and extending in the same direction as the select jacks; a jack support edge (B) similar to the jack posture correcting edge is provided projectingly on the attractive select face in a position which approximately quarters the same face together with the jack posture correcting edge (A), the attractive select face (30) being the highest at the jack posture correcting edge (A) and the jack support edge (B) and inclined down­ ward in directions farther from the said edges; poles (6c) of electromagnets (4c) are provided on the jack posture correcting edge and on both sides of the jack support edge, and poles (81c, 82c) of permanent magnets are provided on both outsides in the jack support edge direction of the poles (6c) of the electromagnets (4c).

Description: The present invention relates to an electromagnetic needle selected in a knitting machine, particularly a flat knitting machine. There is known a needle selector for selecting a needle to be operated for knitting in which, using electromagnets, when a select jack, etc. associated with the needle to be selected become opposed to one electromagnet, the electro­ magnet is energized to attract the select jack, etc. to a position for abutment with a cam which displaces them (see Japanse Patent Laid Open No. 12887/80). In the known apparatus, a set of needle selecting electro­ magnets are opposed to each other to constitute a passage therebetween, and the selector is passed through the said passage while one electromagnet is operated to attract the selector to that electromagnet, thereby effecting needle selection. However, the position of the selector passing through the passage is not constant, nor is constant the moving distance of the selector attracted, so the select­ ing operation is apt to be unstable. The present invention has been accomplished in view of the above-mentioned points and it is the object thereof to per­ mit highly accurate selection in a short time while eliminat­ ing drawbacks in electromagnetic needle selection such as lowering of the selection accuracy caused by the selection in an irregular condition of members to be selected such as the selector, etc. arrived at the position opposed to an electromagnet, and prolonging of the time required for the selection. For solving the problems the invention proposes an electro­ magnetic selector device in which a selector is supported by a carriage so that an attractive select face of the selector moves along and in sliding contact with an upper edge of each of thin plate-like select jacks supported rockably by a support jack through a support member, the attractive select face of the selector being provided with a jack posture correcting edge projecting from the attractive select face and extending in the same direction as the select jacks; a jack support edge similar to the jack posture correcting edge is provided projectingly on the attractive select face in a position which approximately quarters the same face together with the jack posture correcting edge, the attractive select face being the highest at the jack posture correcting edge and the jack support edge and inclin­ ed downward in directions farther from the said edges; poles of electromagnets are provided on the jack posture correcting edge and on both sides of the jack support edge, and poles of permanent magnets are provided on both outsides in the jack support edge direction of the poles of the electro­ magnets. The operation of the device is the following. During knitting, the attractive select face of the selector supported by the carriage is brought into sliding contact with an upper edge of each of plural thin plate-like select jacks inserted in needle grooves in a rockably supported state by the support member. All the jacks are made uniform in posture by the jack posture correcting edge perpendicular­ ly intersecting the advancing direction of the carriage and extending projectingly from the attractive select face in the same direction as the select jacks. When a predetermined select jack to be selected has become opposed to the upper surface of the jack posture correcting edge of the attractive select face, a set of electromagnets provided on the jack posture correcting edge are energized, thereby allowing a half of the upper edge of the select jack to be attracted by one electromagnet, and with subsequent movement of the carriage the select jack is tilted along the inclination of the attractive select face in an attracted state of the select jack upper edge to a half of the attractive select face and in a supported state of the select jack on the associated support member, whereby the select jack is separated from the other select jacks. One way of carrying out the invention is described in detail below with reference to drawings which illustrate an embodi­ ment in which: Fig. 1 is a side view, partly in longitudinal section, of a selector device including a needle bed and a selector; Fig. 2 is a plan view of the selector; Fig. 3 is a front view thereof; Fig. 4 is a bottom view of the selector and rake cams, with a selector mounting base removed; Fig. 5 is a sectional view taken on line C-C of Fig. 3; Fig. 6 is a sectional view taken on line D-D of Fig. 3; Fig. 7 is a sectional view taken on line E-E of Fig. 6; Fig. 8 is a sectional view taken on line F-F of Fig. 6; Fig. 9 is a front view showing a relation between the selector and select jacks. The Figures show an electromagnetic needle selector 1 which is mounted to an earth plate 3 of the carriage which reci­ procates above a needle bed 2. It has electromagnets 4a, 4b, 4c, 4d and permanent magnets 5a, 5b, 5c, 5d. Since the electromagnets 4a, 4b, 4c and 4d are of the same shape, the structure of only 4c or 4d (Figures 5 to 8) will now be explained. Numerals 6a - d denote pure iron for magnetic poles, having a thinly projecting base end portion, with non-magnetic liners 71a and 72a being disposed on both sides thereof. Further outside are disposed L-shaped harden­ ed soft iron plates 81a and 82a side by side whose L-shaped fore ends are close to the magnetic pole pure irons 6a - d. Further, a positioning pin 10 is inserted in a slot 9 formed in a straight line through the magnetic pole pure iron, non-­ magnetic liners 71a, 72a and L-shaped hardened soft iron plates 81a, 82a to prevent free movement of those components. The magnetic pole pure irons 6a - d, non-magnetic liners 71a, 72a and L-shaped hardened soft iron plates 81a, 82a thus connected in series are held in a plural number sand­ wichwise with spacers 11, 12, 13 and side plates 14, 15 which are formed of an abrasion-resistant, non-magnetic, hard material, and pins 16 are inserted through these components in three positions and fixed on both sides with nuts 17 to provide an integral construction (Figures 5 and 6). Since the spacers 11, 12 and 13 sandwich base portions of the L-shaped hardened soft iron plates 81 and 82, gaps are formed between upper portions of adjacent L-shaped hardened soft iron plates 81a, 81b, 81c, 81d and also of 82a, 82b, 82c,82d. Permanent magnets 51a, 51b, 52a and 52b are inserted in those gaps, provided they are not inserted between 81b and 81c and between 82b and 82c. These magnets are inserted in the gaps so that N and S poles are positioned outside and inside, re­ spectively, whereby the L-shaped hardened soft iron plates 81a, 81d, 82a and 82d serve as N pole while 81b, 81c, 82b and 82c as S pole. As a result, magnetic fields are created bet­ ween the L-shaped hardened soft iron plates 81a and 81b; 81c and 81d; 82a and 82b; 82c and 82d, and two blocks of attraction surfaces (magnetic circulative circuits) are provided on the right and left sides of the center in Fig. 5. That is, in the electromagnetic selector 1 there are four circulative circuits (attraction surfaces) formed by permanent magnets. The lower edges of the L-shaped hardened soft iron plates are each in the form of beak, smaller in volume at the central part, so that magnetic flux is concentrated there­ on to enhance the attraction. Joint pieces 20 made of pure iron are fitted in the tops of the magnetic pole pure irons 6a, 6b, 6c and 6d of the electromagnets 4a, 4b, 4c and 4d, and the magnetic pole pure irons 6a and 6b as well as 6c and 6d are made integral respectively using bolts 21; at the same time, the electromagnets 4a and 4b as well as 4c and 4d are rendered continuous at their top portions, respectively, thus forming a horseshoe shape. Two blocks of such horseshoe shape are provided. A coil 22 is wound round each of the magnetic pole pure irons 6a, 6b, 6c and 6d, and the lower ends of the aforementioned two sets of the horseshoe-like magnetic pole pure irons can serve as electromagnets upon energization of the coils 22. The coils are wound so that the electromagnets are the same in polarity as the permanent magnets 5a, 5b, 5c and 5d, the outside being N pole and the inside S. Like the L-shaped hardened soft iron plates 81a, 82a, ....., the fore ends of the magnetic pole pure irons 6a, 6b, 6c and 6d are also thin to enhance the magnetic flux density. The fore ends of the magnetic pole pure irons 6a - 6d are adjacent to the fore ends of the L-shaped hardened soft iron plates 81a - 81d and 82a - 82d through non-magnetic liners 71a - 71d and 72a - 72d. The spacing depends on the thickness of the non-magnetic liners 71a - 71d and 72a - 72d, but it is very small. The attractive select face 30 of the selector 1 projects to the greatest extent at its central longitudinal and transverse lines A and B (Fig. 4) (posture correcting edge and support edge, respectively, hereinafter) and is inclined gently in the arrowed directions. This is for ensuring high attraction of the select jacks 41. In Fig. 1, a jack 36, a positioning jack 37 and a support jack 38 are inserted in a needle groove 35 formed in the needle bed 2. Numeral 39 denotes a positioning pin for holding the position of the position­ ing jack 37. Numeral 40 denotes a grooved select plate, with a select jack groove being formed between the grooved plates 40 and with a select jack 41 being inserted in the so-formed groove. The select jack 41 is centrally fitted loosely on a protuberant support member 42 of the support jack 38. The fitting between the support jack 38 and the select jack 41 leaves a gap which permits a slight (0.2 - 0.3 mm) vertical movement. The support jack 38 is pushed up from below by the spring pressure of the positioning jack 37. Numeral 43 denotes a grooved select sensor plate for timing to energize the electromagnets 6a, 6b, 6c and 6d. The selector 1 is disposed on the needle bed 2 so that the center line B in the advancing direction of the attractive select face 30 of the selector 1 is positioned on the center line of the aforementioned fitting portion. The selector 1 is fixed to the earth plate 3 as previously noted. This fixing is done in the following structure (Fig. 2). The selector 1 is fixed with bolts 53 to a selector mounting base 52 which comprises guide bars 51 disposed in parallel crosses. The selector mounting base 52 is fixed to the earth plate 3 with mounting bolts 54. And rake cams 55 and 56 are fixed with fixing bolts 57 to the underside of the earth plate 3 at a side portion of the attractive select face 30 of the selector 1. The selector 1 of the present invention reciprocates on the needle bed 2 with movement of the carriage (not shown). But, when the select jack 41 corresponding to the needle (not shown) to be selected has become opposed to the selector 1, the electromagnets 6a and 6b, or 6c and 6d, are energized to attract the select jack 41 to the attractive select face 30 of the selector 1, allowing the select jack 41 to move through the rake cams 56 and 57, so that the needle also moves following the movement of the select jack and thus there is performed needle selection. More particularly, it is here assumed that in Fig. 9 the selector 1 is moving leftword together with the carriage (not shown). Among the select jacks 41 located on the advancing side of the selector 1, those falling under the range of A are in their raised or lowered positions at their end portions while keeping their state in the previous course knitting. But their end portions are forced down by a slant face 55a of the rake cam 55. In a state of abutment at end portions with an underside 55b of the rake cam 55 or while being attracted at the opposite ends by the permanent magnets 51a and 52a, the select jacks advance through section B in Fig. 9 and arrive at and near the central part C of the selector 1. At the central part C the center line A of the attractive select face 30 of the selector 1 is the highest and that horizontal, so the select jacks 41 attracted by the permanent magnets 51a and 52a assume a horizontal state. Before the select jacks 41 pass the center line A, that is, when the select jacks 41 have advanced to a position 1/2 pitch this side of the center line A in terms of the pitch of the select jacks arranged in parallel, the electromagnets 4a and 4b, or 4c and 4d, are energized in accordance with a detected signal provided from a needle pitch sensor (not shown). The electromagnets 4c and 4d are energized when a needle is to be brought into its operative position. In this case, the corresponding select jack 41 is attracted for rocking clockwise in Fig. 1. On the other hand, it is when a needle is to be retained in its inoperative position that the electromagnets 4a and 4b are energized. In this case, the corresponding select jack 41 is attracted for rocking counterclockwise. The duration of the above energization is from 1/2 pitch this side up to 1/2 pitch on the other side of the center line of the selector 1 in terms of the select jack pitch. The select jack 41 attracted by electromagnets slides along the attractive select face 30 in a state of abutment of its upper edge with the select face. Even after deenergization, it advances while maintaining its attracted state in energization under the action of the permanent magnet 51a. The selected select jack 41 comes into abutment at an end portion thereof with a cam surface 56a of the rake cam 56 and is thereby forced out to push out the corresponding needle (not shown) through the support jack 38, positioning jack 37 and jack 36. In the selector device of the present invention, the selector 1 is supported by the carriage so that the attractive select face 30 of the selector moves along and in sliding contact with an upper edge of each of thin plate-like select jacks 41 supported rockably by the support jack 38 through a support member 42. The attractive select face 30 of the selector 1 is provided with the jack posture correcting edge A projecting from the attractive select face 30 and extending in the same direction as the select jacks. The jack support edge B similar to the jack posture correcting edge A is provided projectingly on the attractive select face 30 in a position which approximately quarters the same face together with the jack posture correcting edge A. The attractive select face 30 is the highest at the jack posture correcting edge A and the jack support edge and is inclined downward in directions farther from the said edges. The poles 6a - 6d of electromagnets 4a - 4d are provided on the jack posture correcting edge A and on both sides of the jack support edge B. Poles 81a - 81d and 82a - 82d of permanent magnets 51a, b and 52a, b are provided on both outsides in the jack support edge direction of the poles of the electromagnets. Under such construction, all the select jacks inserted in the needle bed 2 are once arranged uniform by the posture correcting edge A at the center of the attractive select face 30 of the selector 1 underside as mentioned above. Before and after this, the select jack to be selected can be pivoted and selected in one direction about the support edge B of the attractive select face 30 upon energization of electromagnets also constituting the same face. During this selecting operation the whole or part of the upper edge of the select jack is held in contact with the select face 30 of the selector 1, so the selecting operation is accurate and can be done in an instant.

Claims: An electromagnetic selector device for a knitting machine, particularly a flat knitting machine, in which a selector (1) is supported by a carriage so that an attractive select face (30) of the selector (1) moves along and in sliding contact with an upper edge of each of thin plate-like select jacks (41) supported rockably by a support jack (38) through a support member (42), said attractive select face (30) of the selector being provided with a jack posture correcting edge (A) projecting from the attractive select face (30) and extending in the same direction as the select jacks (41); a jack support edge (B) similar to said jack posture correct­ ing edge (A) is provided projectingly on said attractive select face (30) in a position which approximately quarters the same face together with said jack posture correcting edge (A), said attractive select face (30) being the highest at said jack posture correcting edge (A) and said jack support edge (B) and inclined downward in directions farther from said edges; poles (6a - 6d) of electromagnets (4a - 4d) are provided on said jack posture correcting edge (A) and on both sides of said jack support edge, and poles (81a - 81d, 82a - 82d) of permanent magnets (51a,b, 52 a,b) are pro­ vided on both outsides in the jack support edge direction of said poles (6a - 6d) of the electromagnets (4a - 4d).

Inventors: TOBE, HIDEHARU
Applicants: HEIKO SEISAKUSHO, LTD.
Application year: 1987
Main classification: D04B15
IPC codes: D04B15, D04B27