US3851500A

US3851500A - Circular knitting machine needle selecting apparatus

Info

Publication number: US3851500A
Application number: US00135319A
Authority: US
Inventors: R Wolfshagen
Original assignee: Rockwell International Corp
Current assignee: Boeing North American Inc
Priority date: 1971-04-19
Filing date: 1971-04-19
Publication date: 1974-12-03
Anticipated expiration: 1991-12-03
Also published as: AR195483A1; BE782283A; NL7204087A; ZA721490B; CH534758A; IT957577B; DE2217115A1; ES401920A1; FR2133604B1; BR7202311D0; FR2133604A1

Abstract

Broadly, there is disclosed an improved apparatus and method for selecting controllably certain discrete bodies one from the other as the bodies move past a site of selection. More specifically, there is disclosed method and apparatus for selecting which of the needles carried within the tricks of the needle cylinders of rotary knitting machines are caused to knit or not to knit. In the device described, selection of the needles actually results, in the preferred arrangement, from the operation of magnet means including permanent and electromagnets upon edge portions of patterning or needle jacks located beneath the needles themselves, rather than by direct action upon the needles. The actuating or selecting mechanism generally comprises a first or lower magnet means that includes a pair of poles, one of which is shaped in such a fashion as to provide a cam surface against which one end (in this case, the lower end) of the jacks will be cammed into a preselected position. This preselected position is one in which the other ends of the jacks, here the upper ends, are moved into a select position where they can be magnetically engaged by a second or upper magnet means. The second magnet means includes a plurality of electromagnets, which in operation are sequentially energized, and permanent magnet means that serve to maintain the needle jacks in position for selection to the non-operative position and to maintain the jacks in the nonoperative (non-knitting) position for a length of time sufficient to permit the jacks to clear the knitting cams located circumferentially about the periphery of the needle cylinder.

Description

[ 5] Dec. 3, 1974 1 CIRCULAR KNITTING MACHINE NEEDLE SELECTING APPARATUS [75}- Inventor: Ronald G. Wolfshagen, Fullerton,

Calif.

[73] Assignee: Rockwell International Corporation,

Pittsburgh, Pa.

22 Filed: Apr. 19, 1971 21 Appl. No.: 135,319'

52 US. Cl .Q. 66/50 R [51] Int. Cl D041) 15/78 [58] Field of Search 66/50 R, 25, 75, 154 A, 66/50 A, 50 B [56] References Cited UNITED STATES PATENTS 3,262,285 7/1966 Beguin et a1...'. 66/50 R 3,283,541 11/1966 Cerjat 1. 66/50 R 3,292,393 12/1966 Ribler 66/154 A X 3,449,928 6/1969 Schmidt et al.-. 66/50 R 3,518,845 7/1970 Cerjat 66/50 R 3,710,594 l/l973 Bourgeois 66/50 R FOREIGN PATENTS OR APPLICATIONS 1,116,744 6/1968 Primary Examiner-Wm. Carter Reynolds I Attorney, Agent, or FirmFloyd S. Levison; Dennis OConnor; Richard A. Speer [57] ABSTRACT Broadly, there is disclosed an improved apparatus and Great Britain 66/50 R method for selecting controllably certain discrete bodies one from the other as the bodies move past a site of selection. More specifically, there is disclosed method and apparatus for selecting which of the needles carried within the tricks of the needle cylinders of rotary knitting machines are caused to knit or not to knit. 1n the device described, selection of the needles actually results, in the preferred arrangement, from the operation of magnet means including permanent and electromagnets upon edge portions of patterning or needle jacks located beneath the needles themselves, rather than by direct action upon the needles. The actuating or selecting mechanism generally comprises a first or lower magnet means that includes a pair of poles, one of which is shaped in such a fashion as to provide a' cam surface against which one end (in this case, the lower end) of the, jacks will be cammed into a preselected position. This preselected position is one in which the other ends of the jacks, here the upper ends, are moved into a select position where they can be magnetically engaged by a second or der.

12 Claims, 8 Drawing Figures I III mf Pmmngm m I SHEET 18? Pmmwn 319M SHEET 30F 4 PAIFNIE can 31974 SHEET U 0F 4 FIG. 7.

Indexing Secf/an Depress/0g Ac/uaf/ng Sec/ion Seal/on CIRCULAR KNITTING MACHINE NEEDLE SELEIITING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention v i As briefly noted above, the present invention is concerned with circular knitting machines generally known as the large diameter body type, but is not limited to that type of knitting machine solely. Circular knitting machines basically comprise a cylindrical needle cylinder which is mounted for rotation about a vertical axis. The outer periphery of the needle cylinder is formed with a large number of slots of generally rectangular cross-sectional configuration, commonly referred to as tricks, extending longitudinally generally parallel to the cylinder axis. Within these slots or tricks are disposed a plurality of knitting needles and usually one or more sets of needle jacks to accomplish their various knitting functions. v

. Operation of then eedles or needle jacks, if they are to be the functioning means by which needles are caused to knit or not to knit, is controlled through appropriately located cams that at various times are in contact either with the needles or, in the present description, with the needle jacks. The raise cams, i.e. those that cause the needles to move vertically upwardly into the knit position are normally located just adjacent the outer periphery of the needle cylinder so that buttsor other protrusions on the needle jacks can cooperate therewith. I

By and large, the only way in which knitpatterns heretofore could by changed in existing equipment was to physically disassemble the various carn segments making up thecam rings and then reassemble themachine with an entirely different cam configuration to deliver the desired knit fabric. This procedure is obviously one that is time consuming, as well as one resulting in excessive cost. The present invention eliminates this needless and costly interruption of service by providing a combined permanent and electromagnetic actuator assembly which can be controlled by suitable means'to automatically determine whether or not individual needle jacks will be physically disposed to cause knitting or not. w

2. Description of Prior Art Although it was indicated above that most knitting machines patterning changes have been on a pure disassemble-reassemble basis, some work has been done in the prior art to electromagnetically control patterning jacks for the purpose of simplifying needle selection procedures. For example, Beguin et al. U.S. Pat. No. 3,262,285 discloses an electromagnetic needle selection system which utilizes electromagnets in a variety of ways to move jacks from a non-knitting to a knitting position upon energization of an electromagnet. ln apparatus of this sort, however, the selecting mechanism is one of comparatively slow response time. Addi tionally, due to the circumferential spacing which must exist between successive needle jacks and the fields to operate mechanical transducers. The mechanical transducers in turn cooperate with butts extending out from the lower ends of the patterning jacks. Here again, the fact that mechanical linkage must exist between the element to be operated upon and the operating driver results in comparatively poor time response which in turn necessitates slower operating speeds and decreased production rates. I

The actuating mechanism of the present invention goes beyond those existing in the prior artby virtue of providing for the first time a system utilizing both permanent magnetic fields and electromagnetically generated fields to assure not only extremely quick response time but also to produce surety in operation. It should be mentioned at this point that it would be possible to operate the present actuating mechanism solely through the use of electromagnets but no constructive purpose would be gained since permanent magnets can easily replace the function of certain of the electromagnets and thereby eliminate field controlling devices that would otherwise be necessary. Additionally, the present apparatus, because of its high rate of response can be effectively controlled by electronically programmed apparatus to switch from one desired pattern to another with no down time for the alteration of patterning cams.

It is a principal object of this invention to provide an improved method and apparatus for controllably selecting certain discrete bodies one from the other as the bodies move past a site of selection.

It is a further principal object of this invention to provide an improved apparatus and method for selectively effecting positioning of pattern or needle jacks mounted wiithin the tricks of theneedle cylinder of a circular knitting machine to place the jacks in either a selected or a non-selected position, as desired.

Another object of this invention is to provide an improved jack actuator for knitting machines, which'actuator includesm'eans for positioning the jacks in a normally operative condition unless acted upon by a different part of the actuator. v

Another object of thisinvention is to providean im proved jack actuator for use on a rotary knitting machine, which actuator includes means forsubjecting the jacks to atranslating magnetic field such that any selected jack can be subjected to the field independently of any adjacent or adjoining jack. I

An additional object of this invention is to provide an improved jack actuator for use with rotary knitting machines which includes means for positioning the jacks in a select position from which they can unerringly be caused to move to positions resulting in knitting or nonknitting, as desired.

A further object of this invention is to provide an improved jack actuator for use with rotary knitting machines which includes upper and lower magnet means for controllably effecting positioning and corresponding ends of the jacks.

Other objects and advantages of this invention will be in part obvious and in part apparent by reference to the FIG. 3 is a front elevation of a cam box illustrating the manner in which the jack actuator is located with respect tothe jack raising cams;

FIG. 4 is a front elevation of the improved jack actuator of this invention;

FIG. 5 is a side elevation of the improved jack actuator of this invention;

FIG. 6 is a top plan view of the improved jack actuator with parts removed to show the manner in which the magnets of the upper part of the actuator are disposed; and

FIG. 7 is a bottom view of a fragmentary portion of the structure of FIG. 3 illustrating the manner in which the lower portion of the jack actuator effects positioning of the jacks.

FIG. 8 is a top elevation of the lower portion of the magnetic static force assembly showing the two lower magnetic poles.

Generally, the actuator apparatus of this invention is to be used in conjunction with rotary knitting machines and preferably with large diameter machines having a multiplicity of yarn feeds, for example, 48 or more. Applicability of the principles and structures herein described are, however, relevant also to the small diameter knitting machines of the type now widely used to produce hosiery. It further must be understood, as mentioned earlier, that the method of selection here described might apply as well to a linear system where discrete bodies are caused to travel past a site of selection. The invention will be described specifically in conjunction with a particular type of apparatus, viz., a knitting machine, but it will be appreciated that its use can well extend into other areas of technology and engineering.

The construction and operation of the actuator apparatus can best be understood by referring to the drawings and specifically to FIG. 1 of the drawings in which the actuator apparatus 10 is shown mounted adjacent the external wall of the needle cylinder 11 for cooperation therewith. Mounted between needle cylinder 11 and actuator apparatus 10 is apattern jack 12 which is of the rocking type having a fulcrum located approximately midway between its upper and lower ends. Located immediately above jack 12 is an intermediate jack [3 and finally the actual needle 14 which performs the kntting operation is positioned immediately above intermediate jack 13. Pattern jack 12, intermediate jack l3 and the knitting needle 14 are all mounted within a slot or trick present in the outer periphery of needle cylinder 11. The entire outer periphery of the cylinder is slotted to provide a series of the tricks which extend substantially parallel to the axis of rotation of the knitting cylinder (not shown).

The actuator apparatus 10 is mounted on the machine base that also carries the needle cylinder 1 1. Also shown in FIG. 1, immediately beneath the actuator apparatus and secured to the machine base is a jackraising cam 15 that is also shown in FIGS. 2 and 3 of the drawings. These jack-raising cams are mounted on the machine in segments referred to as cam boxes and are disposed completely around the needle drum circumferentially, so that all jacks 12 during each full cylinder rotation may be acted upon by the raising cam 15 if this is desired.

Also shown in FIG. 1, immediately above the actuator apparatus and secured to machine structure, is a jack lowering cam 16 that is also shown in FIGS. 2 and 3 of the drawing. These jack lowering cams are disposed completely around the needle cylinder circumferentially, so that the butts of all raised intermediate jacks 13 during each full cylinder rotation are acted upon by the jack lowering cam. These intermediate jacks in turn bear upon the corresponding raised pattern jacks 12 to return them to the lowered position for selection or non-selection by the succeeding actuator apparatus. FIG. 1 also shows, adjacent to the needle 14 and secured to machine structure, a needle cam 17. These needle cams are disposed completely around the needle cylinder circumferentially, so that the parts of all raised needles 14 are acted upon by the needle cam to lower them after they take yarn to form a stitch, and to cause them to perform stitch formation action.

Having described the general environment in which the actuator apparatus 10 operates, the construction of the actuator apparatus might best be seen by referring to FIGS. 4 and 5 of the drawings. The apparatus itself is made up of two principal operating subassemblies.

One of these comprises a magnetic static force asembly means 20 which is located adjacent the lower end of the actuator apparatus and which includes permanent magnet means 28 with upper pole 30 and lower poles that exert a magnetic force against the lower ends of the pattern jacks 12 as they travel past these magnetic elements. I

The upper part of the actuator apparatus 10 has been designated as a magnetic force translation assembly means and is indicated by the numeral 21. The magnetic force translation asssembly means includes a plurality of electromagnets 22 each of which is less than the spacing between the leading edges of two adjacent jacks'in width at its pole extreme and arranged in two levels at predetermined intervals to successively overlap each other at the pole extremities. This arrangement enables a very narrow and yet continuously effective sequential magnetic field to be applied to the open end of any pattern jack [2, as it progresses past the actuator apparatus, without adversely effecting its immediate neighboring jacks, and without reliance on friction or other mechanical means to overcome the at- I traction of the static magnetic force assembly means 20. The magnetic force translation assembly2l also includes a jack indexing magnet 23 (FIG. 4) which are in this case shown to be permanent magnets but which may, alternatively, also be in the event it should be desired. The function of this magnet is to so effect the position of the pattern jacks that they are in'readiness to be acted upon by the electromagnets 22 when desired. Further, following the electromagnets 22 is jack latching magnet 24 which will maintain magnetic engagement with any jacks that have been acted upon by the electromagnets and hold them in the selected or nonknitting position for the required length of time to ensure that the lower end of the pattern jack will avoid any contact with one of the raising cams 15.

The exact layout of the permanent jack indexing magnet 23 selecting electromagnets 22 and jack latching magnet 24 is shown clearly in FIG. 6 where the uppermost pole of each of the magnets is shown, the electromagnets 22 having coils 25 mounted on the closed ends thereof. These coils are, of course, connected by means of wires 26 to suitable sources of regulated voltage. In operation these magnets 22 are energized in sequence starting with the first uppermost magnet 22 immediately adjacent the jack indexing magnet 23. After level, has been energized after this second electromagnet 22 has been energized temporarily it is deenergized a predetermined time after the third of the e lectromagnet 22, which is located on the upper level, has been energized. This third electromagnet 22 is deenergized at a predetermined time after the selected jack has progressed to a location where the jack latching magnet 24 can maintain the magnetic engagement of the jack with upper magnet'means 21. By this method of raising and sequenced energization, the fields created by the electromagnets in effect travel as a narrow continuous and non-interrupted energy front across the face ofthe'magnetic force translation assembly. Although the figures do not clearly indicate it, all of the magnets are of the usual U shape configuration so that the upper set of pole faces represent the termi- I hear when drawn toward the pole faces through the indexing action of the jack indexing magnet 23 and subsequently the upper ends of those jacks which are held by theselective action of electromagnets 22 and the holding action of jack latching magnet 24. By contacting guard cam'27 there is not subsequent wear or attrition of the pole surfaces ofthe various magnets or the materialwithin which the magnets are mounted. Also as seen in FIG.'6-, the bearing surface 29 of cam 27 forms an arc which when in proper relationship with the needle cylinder is concentric, with the cylinder. 1 Therefore, those jacks which are held against surface 29 by sequential energization of electromagnets 22 and subsequently held by jack latching magnet 24 are maintained in'a fixed positional orientation within their respe'ctive tricks relative to the actuator apparatus while progressing past the actuator apparatus.

i Returning now to the-lower or first magnet means (magnetic static force assembly 20) this structure is made up of a first and second pole, the first pole being designated by the numeral 30 and the second and lower pole indicated by the numeral 31. The first pole 30 performs no function other than that of providing a magnetic attraction helping to hold the lower end of pattern jacks 12 coming into contact with the magnetic static force assembly. The second pole 31, it will be noted,

however, particularly by reference to FIGS. 3, 7 and 8, I has a cam surface 32 which is configured to cause the lower end of the jacks to move inwardly toward the needle cylinder and a cam surface 37"which is configured to permit the lower end of the jacks to move outwardly from the needle cylinder if this is desired. This first cam surface 32 results in the upper ends of every one of the jacks 12 moving to a position of close proximity with upper magnet means 21 where they can be pulled against cam surface 29 by the attraction of jack indexing magnet 23 and subsequently selected to notknit, if this is desired, through interaction with magnetic fieldsoriginated with electromagnets 22 and subsequently following jack latching magnet 24.

The second cam surface 37 of .pole 31 permits the lower endsof the jacks not selected by upper magnet means 21 and through interaction with the static magnet field of lower magnet means 20, to be displaced outwardly along the cam surface 37 to a position where the notched lower section of the .jacks 12 will engage and be acted upon by the raising-cam 15. This can be'stv be seen in FIG. 1 where the lower end of the jack 12 is shown in the displaced position it assumes when it is not returned against surface 29 of guard cam 27 by en- .ergization of electromagnets 27. As shown, the notched lower end of the jack 12 will contact andsubsequently follow the contour of raising cam 15, which will raise the intermediate jack 13 and the knitting needle 14 finally into position to take yarn for knitting.

By referring to FIGS. 3 and 8 of the drawings, it can be seen that the lower pole 31 of the magnetic static force assembly'is constructed in such a way that'the bottoms of pattern jacks 12 make contact with cam surface 32, depending upon whether or not they have been previously in a knit (raised) or a non-knit (lowered) position. Those jacks that have been in the lowered or non-knit position are designated by numeral 33 and first contact surface 32 about midway of the lower pole 31. Those jacks that have been in the raised or knit position are indicated by numeral 34 and contact surface 32 of pole 31 at an earlier point. As'seen in FIG. 3, these jacks 34 are additionally in the process of being lowered by contact with'intermediate jacks 13 which have butts cooperating with lowering cam 16. This embodiment is preferred to permit. a closer spacing of the jack actuator apparatus 10 circumferentially about the periphery of the needle cylinder as it is clear that the jack lowering action could be accomplished before jack contact with .cam surface 32. The region-from the point of contact of jacks 34 with surface 32 to a location about midway of the lower pole 31 might be called the jack depressing section. This language is functionally descriptive because as the jacks progress from the depressing section towardthe mid section, or jack indexing section, the lower ends of the jacks are depressed inwardly toward the needle cylinder 11 and into the respective tricks in the cylinder. In this orientation the stepped or notched-lower ends of all

jacks

33 and 34 are located outside of a planewhere they can come into contact with jack raising cams15.Such inward movement of the lower end obviously results in outward movement of. the upper ends of jacks 12 to bring them in close proximity with the guard cam 27 of the upper magnetic means 21 (magnetic translation force assembly); When this movement has been achieved and any one jack is located in the jack indexing section, theupper ends of jacks 12 will be acted upon by the indexing magnet 23 of upper magnet means 21 which partially neutralize the effect of the tween any jack 12, located circumferentially within the indexing section jack and the cam surface 29 provided that the jack 12 is an infinitely rigid element. However, any real jack element is'not infinitely rigid and when loaded by forces acting at right angles to the longitudinal dimension at known distances on each side of a center support the jack will deflect in a known manner within its elastic limit and depending upon its cross section geometry. Similarly, any jack 12 located circumferentially within the jack indexing section with its lower end held against cam surface 32 by interaction with the magnetic field of lower magnet means 20, its mid-length located fulcrum point bearing on pivot cam 40, and its upper end interacting with the magnetic field of jack indexing magnet 23 of upper magnet means 21 will elastically and in a predetermined manner deflect outwardly toward the pole ends of jack indexing magnet 23 until contact is made with surface 29 of guard cam 27. Further, the elastic properties of a jack 12 are predetermined such that jack contact with all three

cam surfaces

32, 40 and 29 will occur simultaneously in the jack indexing section of the actuator for each and every jack in a full cylinder revolution irrespective of normal wear, obtainable part tolerances and uneven temperature expansions which would otherwise cause the dimension air gap relationship between the jack and the magnets to be indeterminant. This condition is necessary for error free selection because first, clearance (air gaps) to the magnet means and 21 are now the same for each and every jack at the select position, and second because with the jack bearing on the pivot cam surface 40 there is no possibility that jack impact with this surface, through cooperation with cam surface 37 on pole 31, can occur, such impact causing undesired bounce or recoil of the jack away from the actuator apparatus. Such acondition would result in selection errors at high jack circumferential speeds. This action of positioning the jacks 12 in a select positionthen permits energization of the electromagnets 22 to provide the additional force that determines whether or not the upper end of the jack will be magnetically held against the guard cam 27 in opposition to the magnetic force of lower magnet means 20 acting on the lower endof the jack. v

Those jacks that are selectively held against guard cam 27 and designated bynumeral 35 in FIG. 8. Should the electromagnet 22 be sequentially energized, the upper ends of the jacks 35 will be held to bear against the guard cam 27 as the jack is translated past the actuator apparatus by rotation'of the needle cylinder 11. The lower ends of jacks 35 are thereby maintained in a position where notched portion at the lower end of the jacks will avoid contact with raising cam 15. This can best be seen in FIG. 2 where the lower end of jack 12 is shown in the position it assumes when it is held by electromagnets 22 to clear raise cam 15. The result is then that the pattern jack merely passes behind the raising cam rather than following the contour of the cam which would raise the intermediate jack l3 and the knitting needle 14 finally into position to take yarn for knitting.

If the electromagnets 22 are not energized, then the lower end of any pattern jack 12 will continue to be held by the

lower magnets

30 and 31 so that it will follow the contour of pole cam surface 32 on the pole cam surface 37 into what is called the jack actuation section (see FIG. 8). This is referred to as the jack actuation magnetic attraction of lower magnet means 20 to move awsay from the cylinder and out of its trick to a position where it will engage and be acted upon by the raising cam 15. Jacks so disposed are identified by numeral 36 in FIG. 8. Such outward movement of the lower end obviously results in inward movement of the upper end, the jack 26 pivoting about its fulcrum point which is bearing on pivot cam 40, thereby increasing the displacement between the upper end of jacks 36 and the upper magnet means 21. Conversely, those jacks 35 which are acted upon by electromagnets 22 progress along cam surface 29 into close proximity with the jack latching magnet 24 which ensures that those selected jacks will have their lower ends held out of the plane where they can make any contact with raising cams 15 again as shown in FIG. 8.

In operation, pattern jacks 12 are vertically mounted in the longitudinally extending tricks of the needle cylinder 11 and rotate in a path on the periphery of this cylinder. At each yarn feeding station around the periphery of needle cylinder 11 there is located one of the actuator apparatus 10 so that at that location any needle can be caused to knit or not to knit depending upon whether or not the electromagnets 22 are sequentially energized. The purpose for providing a multiplicity of electromagnets to effect the selection, when desired, of certain of the pattern jacks l2'is because of the desirability of providing as many needles in the needle cylinder as possible and to rotate the needle cylinder at an angular rate which is not limited by the selection v means. Obviously, to do this the lateral dimensions of each needle must be kept to an absolute minimum and when doing this, it then becomes necessary that a very narrow and yet continuously effective magnetic field must be maintained to ensure that any one of the jacks are held long enough to remove them from the infue nc'e of the lower magnetic means 20 into a selected position of non-knitting. Also, it is necessary that the lower magnet means 20 must hold jacks 36 in contact with'cam surface 27 long enough to pivot their lower ends into a position where they will engage and be acted upon by raising cam 15. Because the magnetic force acting on the jack is directly, relatable to the edge or thickness dimension of the 7 jack, a practical force limit exists. Also, because the force required to displace the jack against its inertia becomes increasingly great as the time available to displace the jack becomes less, it follows that, for high angular cylinder speeds,

the amount of. jack displacement which can be practically accomplished within a time period equivalent to one jack spacing may be inadequate to fully displacethe notched lower end of the jack 36 from the position where it will avoid contact with the raising cam 15 to the positionwhere it will engage and cooperate with the raising cam. This condition is accommodated by accomplishing jack displacement, over a time period equivalent to multiplicity of jack spacings, which in turn determines the need for,the plurality of sequentially energized electromagnets 22 to ensure that the individual selected jacks 35 are held long enough to remove their lower ends from the influence of the lower magnet means 20. When the drum is rotated so that the needles turn past each of the various selection stations, the bottom ends of the pattern jacks first come into contact with either the jack depressing or jack indexing section of the lower pole 31 of the magnetic static force assembly. At this time the jacks with the cooperation of jack indexing magnet 23 are is a select position with the notched lower ends of the jacks retracted into their cylinder tricks and located outside of a plane where they can come into contact with jack raising cams 15. Here if the electromagnets 22 remain unenergized, the jack will pivot about its fulcrum point bearing on pivot cam 40 the lower end of the pattern jack in cooperation with lower magnet means 20 will followalong the contour of cam surface 37 of lower pole 31 and move outward from the needle cylinder to the position where it will be acted upon by the next following raise cam 15. This of course vertically shifts all of the associated

elements

12, 13 and 14 upwardly and will cause the needle to take yarn and then to subsequently draw down a new stitch. On the other hand, if the first of the electromagnets 22, and by first is meant the first one that is approached by any given traveling pattern jack, is energized, it will act to hold the upper end of .the selected jack 12 against the guard cam 27. With the upper end of jack 12 held against guard cam 27, the bottom end of the jack is maintained within its cylinder trick corresponding to the position shown in FIG. 20f the drawings where it is located in a plane where it will completely pass the raise cam 15. Therefore no resultant upward movement of jack l2 and effected parts will take place. The permanent magnet jack latching magnet 24 will then take over after all of the electromagnets 22 have been energized in sequence and maintain the grip on the upper end ofjack 12 to assure that the lower end of the jack will pass by the jack raising cam. Thus it can be said in this arrangement that the jack indexing magnet 23 is located rotationally ahead of the permanent electromagnets 22 and that the jack latching magnet 24 is located rotationally behind the elecous that there has been provided an improved and radi- I cally different type of apparatus which is capableof selecting discrete articles of very small lateral dimensions with minimum probability of selecting or adversely effecting any of the other individual articles immediately adjoining or adjacent the article to be selected. In this case when knitting with. a rotary knittingmaChine the selection must be certain and accurate at all times and fr the first time, this mechanism provides a magnetic means formaking accurate selection of pattern jacks at high rotational cylinder speeds.

Although the present invention has been described in connection with preferred embodiments, it is to be understood'that modifications and variations may be resorted to without departing from the spirit and scope of the invention as those skilled in the art will readily understand..Such modifications and variations are considered to be within the purview and scope of the invention and the appended claims.

I claim:

1. Actuator apparatus for selectively effecting positioningof needle jacks mounted within the tricks of the needle cylinder of a circular knitting machine to place the jacks in either a selected or a non-selected position,

as desired, said apparatus comprising a magnetic static magnetic force translation assembly means including a plurality of electromagnets physically arranged in a predetermined mannerto enable them selectively to magnetically engage the other end of each selected jack with sequentially applied magnetic fields overcoming said magnetic means of said static force assembly means to hold the selected jack in the selected position where the associated needle will be caused to knit.

2. An apparatus as defined in claim 1 in which a pivot cam is located between said magnetic static force assembly and said magnetic force translation assembly means to provide a fulcrum about which the jacks will pivot when acted upon by said magnetic static force assembly means. 2

3. An apparatus as defined-in claim 1 wherein said magnetic means comprises a cam pole having a surface adapted to be contacted by said one end of each jack,

said contact surface being configured to cause the jacks to move into a position where they can be selected by said magnetic force translation assembly means when desired. I

4. An apparatus as defined inclaim 1 in which a pivot cam is located between said magnetic static force assembly and said magnetic force translation assembly means to provide a fulcrum about which each jack will pivot when acted upon by said magnetic static force assembly means and in which said magnetic means comprises a pair of poles positioned to magnetically engage said one end of each jack, at least one of said poles being configured to cause each jackto move into a position where it can be selected by said magnetic force magnetically engage said one end of each jack, at least one ofsaid poles being configured to cause the jacks to move into a position where they can be selected by said magnetic force translation assembly means when desired. l

6. An apparatus as defined in claim 1 wherein said plurality of electromagnets are physically arranged in a'manner such that the effective fields thereof overlap fora predetermined length of time when saidelectromagnets are sequentially applied, 'said length of time being such as to enable maintenance of magnetic engagement with any selected jack throughthe amount of arcuatetravel about the axis of rotation of the needle cylinder required to hold the selected jack in the inoperative'position andto enable the jack next following the selected jack to be acted upon by said electromagnets independently.

7. An apparatus as defined in claim 6 wherein at least three electromagnets are present in said magnetic force translating assemblymeans.

8. An apparatus as defined in claim 1 wherein said magnetic force translation assembly includes jack -in dexing magnet means located rotationally ahead of said plurality of electromagnets to cooperate with said magnetic static force assembly means in positioning the jacks in a select position where they can be magnetically engaged by said plurality of electromagnets when they are energized.

9. An apparatus as defined in claim 8 wherein said jack indexing magnet means is a permanent magnet.

10. An apparatus as defined in claim 1 wherein said magnetic force translation assembly means includes jack latching magnet means located rotationally behind said plurality of electromagnets to magnetically engage said other ends of those jacks magnetically engaged by said plurality of electromagnets and hold the jacks in the non-operative position for a predetermined period.

11. An apparatus as defined in claim wherein said jack latching magnet means is a permanent magnet.

12. Apparatus for selectively effecting movement of pattern jacks mounted within the tricks of the needle cylinder of a rotary knitting machine to place the jacks in either an operative or a non-operative position, as desired, and said apparatus comprising:

a. first magnet means for magnetically engaging the lower ends of said jacks to place the jacks in the operative position in which the needles carried in the needle cylinder will becaused to knit, said first magnet means including: i l. a first pole, and

2. a second pole having a cam surface configured to cause the jacks to move to a position of selection;

b. second magnet means for magnetically engaging the upper ends of said jacks to move them into a non-operative position in which the needles carried in the needle cylinder will be caused not toknit,

2. a permanent magnet located rotatably ahead of said plurality of electromagnets to cooperate with said first magnet means in positioning the jacks in a select position where they can be magnetically engaged by said plurality of electromagnets when they are energized, and

3. a permanent magnet located rotatably behind said plurality of electromagnets to magnetically engage the upper ends of those jacks magnetically engaged by said plurality of electromagnets and hold the jacks in a non-operative position for a predetermined period; and

c. a pivot cam located between said upper and lower magnet means to provide a fulcrum about which the jacks will pivot when acted upon by said magnet means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,851,500 DATED December 3, 1974 INVENTOR(S) :Ronald G. Wolfshagen It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, Line 62 "eror" should be --error--.

Column 4, Line 47 following "be" first occurrence insert --an electromagnet--.

Column 9, Line 45 "fr" should. be --for--.

Signed and Scaled this Fourth Day Of January 1977 [SEAL] Attest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner uflarents and Trademarks

Claims

1. Actuator apparatus for selectively effecting positioning of needle jacks mounted within the tricks of the needle cylinder of a circular knitting machine to place the jacks in either a selected or a non-selected position, as desired, said apparatus comprising a magnetic static force assembly including cam means adapted for physical engagement with one end of each of the jacks to place the jack in the selected position in which the each associated needle carried in the needle cylinder will be caused not to knit, magnetic means for holding said one end of each jack in contact with said cam means, and magnetic force translation assembly means including a plurality of electromagnets physically arranged in a predetermined manner to enable them selectively to magnetically engage the other end of each selected jack with sequentially applied magnetic fields overcoming said magnetic means of said static force assembly means to hold the selected jack in the selected position where the associated needle will be caused to knit.

2. An apparatus as defined in claim 1 in which a pivot cam is located between said magnetic static force assembly and said magnetic force translation assembly means to provide a fulcrum about which the jacks will pivot when acted upon by said magnetic static force assembly means.

2. a second pole having a cam surface configured to cause the jacks to move to a position of selection; b. second magnet means for magnetically engaging the upper ends of said jacks to move them into a non-operative position in which the needles carried in the needle cylinder will be caused not to knit, said second magnet means including:

3. a permanent magnet located rotatably behind said plurality of electromagnets to magnetically engage the upper ends of those jacks magnetically engaged by said plurality of electromagnets and hold the jacks in a non-operative position for a predetermined period; and c. a pivot cam located between said upper and lower magnet means to provide a fulcrum about which the jacks will pivot when acted upon by said magnet means.

3. An apparatus as defined in claim 1 wherein said magnetic means comprises a cam pole having a surface adapted to be contacted by said one end of each jack, said contact surface being configured to cause the jacks to move into a position where they can be selected by said magnetic force translation assembly means when desired.

4. An apparatus as defined in claim 1 in which a pivot cam is located between said magnetic static force assembly and said magnetic force translation assembly means to provide a fulcrum about which each jack will pivot when acted upon by said magnetic static force assembly means and in which said magnetic means comprises a pair of poles positioned to magnetically engage said one end of each jack, at least one of said poles being configured to cause each jack to move into a position where it can be selected by said magnetic force translation assembly means when desired.

5. An apparatus as defined in claim 1 wherein said magnetic means comprises a pair of poles positioned to magnetically engage said one end of each jack, at least one of said poles being configured to cause the jacks to move into a position where they can be selected by said magnetic force translation assembly means when desired.

6. An apparatus as defined in claim 1 wherein said plurality of electromagnets are physically arranged in a manner such that the effective fields thereof overlap for a predetermined length of time when said electromagnets are sequentially applied, said length of time being such as to enable maintenance of magnetic engagement with any selected jack through the amount of arcuate travel about the axis of rotation of the needle cylinder required to hold the selected jack in the inoperative position and to enabLe the jack next following the selected jack to be acted upon by said electromagnets independently.

7. An apparatus as defined in claim 6 wherein at least three electromagnets are present in said magnetic force translating assembly means.

8. An apparatus as defined in claim 1 wherein said magnetic force translation assembly includes jack indexing magnet means located rotationally ahead of said plurality of electromagnets to cooperate with said magnetic static force assembly means in positioning the jacks in a select position where they can be magnetically engaged by said plurality of electromagnets when they are energized.

11. An apparatus as defined in claim 10 wherein said jack latching magnet means is a permanent magnet.

12. Apparatus for selectively effecting movement of pattern jacks mounted within the tricks of the needle cylinder of a rotary knitting machine to place the jacks in either an operative or a non-operative position, as desired, and said apparatus comprising: a. first magnet means for magnetically engaging the lower ends of said jacks to place the jacks in the operative position in which the needles carried in the needle cylinder will be caused to knit, said first magnet means including: