US3401539A - Straight bar knitting machines - Google Patents

Description

p 17, 1958 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES Filed Dec. 16, 1965 l4 Sheets-Sheet 1 gmg TCB

' U LL11 scM J82 31 FIG.|(1.

p 1968 w. DUNCAN ETAL STRAIGHT BAR KNITTING MACHINES l4 Sheets-Sheet 2 Filed Dec. 16, 1965 mm 53 S t 2 9 0 Q m F 52 (l z lk om CNN; 8% mm wt 0: Q 3 6 E N N2 mm m uot i S B R cm \wm w a A a h mm -0m L wxv Sept. 17, 1968 Filed Dec. 16, 1965 W. DUNCAN ETAL STRAIGHT BAR KNITTING MACHINES 14 Sheets-Sheet 3 P 7, 1968 w. DUNCAN ETAL STRAIGHT BAR KNITTING MACHINES 14 Sheets-Sheet 4 Filed Dec. 16, 1965 P 1968 w. DUNCAN ETAL STRAIGHT BAR KNITTING MACHINES l4 Sheets-Sheet 5 Filed Dec. 16, 1965 p 17, 1968 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES l4 Sheets-Sheet 6 Filed Dec. 16, 1965 P 17, 1963 w. DUNCAN ETAL STRAIGHT BAR KNITTING MACHINES 14 Sheets-Sheet 7 Filed Dec. 16, 1965 E v 37 .IU a I.

(and- Q 67 66 W FIG.7.

p 17, 1958 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES l4 Sheets-Sheet 8 Filed Dec. 16, 1965 p 1968 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES 14 Sheets-Sheet 9 Filed Dec. 16, 1965 FIGJC).

, P 17, 1958 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES Filed Dec. 16, 1965 14 Sheets-Sheet 1O P 17, 1963 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES 14 Sheets-Sheet 11 Filed Dec. 16, 1965 P 1968 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES 14 Sheets-Sheet 12 Filed Dec. 16, 1965 m m M P 17, 1963 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES l4 Sheets-Sheet 15 Filed Dec. 16, 1965 FIG. l6.

Sept. 17, 1968 w. DUNCAN ETAL 3,401,539

STRAIGHT BAR KNITTING MACHINES Filed Dec. 16, 1965 14 Sheets-Sheet 14 7/ IBI o l o 0 I78 |8O\ I79 177 I76 if O /O United States Patent 3,401,539 STRAIGHT BAR KNITTING MACHINES William Duncan, Alioa, Scotland, and Raymond Blood, Shepshed, England, assignors to Donaidson Brothers (Alloa 1937) Limited and Wiliiam Cotton Limited Filed Dec. 16, 1965, Ser. No. 514,212 Claims priority, application Great Britain, Dec. 24, 1964, 52,516/64 7 Claims. (Cl. 66-148) ABSTRACT OF THE DISCLUSURE A multi-section straight bar knitting machine of rib to plain kind disclosed in British Patent No. 841,471 having plain and rib needles with loop spreader means in each knitting section for transferring rib needle loops of last rib welt courses to the plain needles, whereupon means may be operated for loop doubling, fabric take-off means may automatically hook up and release from the welts, a first transfer means in each knitting section This invention is for improvements in or relating to straight bar knitting machines of multi-section type for producing welts and primarily rib welts.

In this type of machine having two series of needles for producing rib welts in succession, the ribs are usually joined by waste courses, slack courses, and draw threads, and after removing fabric thus produced comprising a plurality of the joined ribs from the rib machine, the ribs are separated and run onto point bars in a separate manual operation. Then the loaded joint bars are fitted in a straight bar plain knitting machine having one series of needles onto which the rib welts are transferred from the points to the needles so that plain fabric blanks can be knitted onto the ribs.

An object of the invention is to avoid the excessive amount of labour and manual operations required in dealing with the ribs from the time they are produced on the two needle bed machine to the time they are applied to the plain one needle bed machine.

The invention provides a multi'section straight bar knitting machine having a plurality of knitting sections each arranged to produce knitted fabric welts in succession, a point bar in each knitting section which is automatically operable in co-operation with the sections needles to automatically transfer a welt at the end of its production from the needles to the associated point bar, a conveyor extending along the machine and adapted to removably receive and carry point bars between the knitting sections and a delivery station, and a transfer mechanism in each knitting section and which is automatically operable at an inner position to automatically receive the associated loaded point bar and at an outer position to co-operate with the conveyor in automatically transferring the loaded point bars to the conveyor for transportation thereby automatically to the delivery station. The machine may be of the rib machine type with two series of needles to produce rib welts, and having loop transfer means automatically operable prior to the transfer of the rib welts to the point bar to automatically transfor the loops from the machine needles to the frame needles. There may be at the delivery station a transferbar-loading machine to which the loaded point bars from the conveyor are transferred at intervals each time operating the machine to transfer a welt from a point bar to a transfer bar until the latter is loaded with a required number of the welts. A plurality of the transfer bars as they become loaded may be transported to the knitting machine for plain fabric to be knitted onto them, or the loaded transfer bars may be stock piled enabling the transportation thereafter to be at any suitable time. Conveniently there may be a delivery transfer mechanism at the delivery station automatically operable to transfer the welts automatically from the conveyor to the transfer bar loading machine.

The welt-producing machine may have displaceable groups of transfer points automatically operable in cooperation with the needles to effect loop doubling automatically before transfer to the point bars. These groups of transfer points may be part of the machines narrowing head, substantially as disclosed in commonly assigned US. patent application No. 512,259.

The welt-producing machine may be of the rib to plain transfer kind disclosed in British Patent No. 841,471 (US. 3,050,967), or in commonly assigned US. patent application No. 480,340.

There may also be hook-up tension means operable automatically for application to the welts during the initial stage of their production and automatically releasable at the end of their production.

Thread carriers may be used for effecting colour changes.

There may be simple means to change the width and/ or the length of the ribs.

When the machine is of the kind according to said Patent No. 841,471 or patent application No. 480,340, it may be at any suitable time employed for knitting plain and rib fabric in continuation.

The fabric produced may be of full or half cardigan type.

The above and other features of the invention set out in the appended claims are incorporated in the constructions which will be hereinafter described as specific embodiments, with reference to the accompanying drawings in which:

FIGURE 1a is a general diagrammatic front view of one part of a straight bar knitting machine according to the invention.

FIGURE 1b is a similar view to FIGURE 1a of the other part of the machine.

FIGURE 2 is a general sectional view of transfer mechanism in the machine.

FIGURE 3 is an enlarged perspective view of needles and rib fabric in the machine.

FIGURE 4 is a similar view to FIGURE 3 showing transfer from rib to plain knitting.

FIGURE 5 is a similar view to FIGURE 3 showing plain fabric being knitted.

FIGURE 6 is a similar view to FIGURE 2 showing the transfer mechanism at a later stage.

FIGURE 7 is a similar view to the upper part of FIG- URE 2 showing the transfer mechanism at a still later stage.

FIGURE 8 is a similar view to FIGURE 7 showing trapper and cutter mechanism operative.

FIGURE 9 is an enlarged front perspective view of the trapper and cutter mechanism.

FIGURE 10 is a detail view of operating means for the trapper and cutter mechanism.

FIGURE 11 is an enlarged detail view of a trapper and cutter device.

FIGURE 12 is a similar view to FIGURE 11 showing the trapper and cutter device at a later stage.

FIGURE 13 is a similar view to FIGURE 11 showing the trapper and cutter device at a still later stage.

FIGURE 14 is a diagrammatic plan view of conveyor mechanism in the machine.

FIGURE 15 is a circuit diagram of electric control means in the machine.

FIGURE 16 is a general sectional view of transfer bar loading means in the machine.

FIGURE 17 is an enlarged detail view of a transfer bar loading operation.

FIGURE 18 is a general sectional view of part transfer operating means of the transfer bar loading means.

Referring to FIGURES la and lb, a multisection straight bar rib knitting machine is provided in this example of the kind disclosed in British Patent No. 841,471 and modified substantially as disclosed in U.S. patent application No. 480,340 to which reference is directed for full details.

Briefly the machine comprises a usual frame F, with drive means DM for the usual main cam shaft 7, usual shogging cam means SCM for shogging the main cam shaft to change between course and fashions operations of the machine, usual coulier mechanism (not shown) for traversing sinker-operating slurcocks (not shown) and thread carrier bars TCB carrying thread carriers TC, usual selvedge stops SS and adjustable lead screw mechanism LSM therefor, and a narrowing head represented by fashioning finger-carrying bars FE, and a usual top disc control shaft TCS. This machine also has in each knitting section, whereof there are four in this example lKS, 2K8, 3KS, 4K5, bearded frame needles 1 in a frame needle bar which is of split needle bar form, comprising a main frame needle bar 2 carrying alternate of the frame needles 1, and an auxiliary needle bar 2a, FIGURE 2, carrying the other alternate frame needles 1. The main needle bar 2 always has usual knitting movements imparted to it by a link connection 3 to a cam follower lever 4 having a cam follower 5 operated by a cam 6 on the machine usual main cam shaft 7. The auxiliary frame needle bar 2a is mounted alongside the main bar 2 for relative vertical movement by controlled operating means associated with said link connection 3 as described in the specification of said patent application. There are also provided associated with the alternate frame needles of the main frame needle bar 2 machine latch and loop spreader needles 9 and operating mechanisms therefor comprising arm connection 10 to a cam follower lever 11 having a cam follower 12 engaging a cam 13 on the shaft 7, and a link connection 14 to a cam follower lever 15 having a cam follower engaging a cam on the shaft 7, as described in said specification. This arrangement is such that at one time, with the machine needles 9 not knitting, all the frame needles 1 are operable to knit plain knitted courses as and when required. In addition rib fabric can be produced as and when required by lowering the auxiliary frame needle bar 2a out of action and introducing the machine needles 9 so that newly fed yarn on the operative frame needles 1 of the main needle bar 2 is also taken by the machine needles 9 which then knit with the operative frame needles 1 to produce the rib fabric RB as represented in FIGURE 3. At any time required, change from rib to plain knitting is accomplished by extra advance of the machine needles 9, FIGURE 4, so that their loop spreader elements 9a spread their loops L, and by re-introducing the auxiliary frame needle bar 2a whereof their needles 1 penetrate the loops L so that all the frame needles 1 can then knit plain fabric with the machine needles rendered inoperative.

The machine is further provided, FIGURES la, 1!), 2 with a point bar conveyor 16 (to be hereinafter fully described) which extends along the machine at an elevated location over the machine needle bar operating mechanism 10, 11 and it has spaced brackets 17 for removably supporting point bars 18, and a first transfer mechanism 19 in each knitting section. This transfer mechanism 19, FIGURE 2, comprises laterally slideway spaced forming arms 20 extending from a rear shaft 21 forwardly between said machine needle operating mechanism 10, 11 and the conveyor 16, operating mechanism (to be described) for pivotally raising and lowering the arms 20 between the conveyor and the needles, pusher arms 22 associated with the arms 20 for raising and lowering and pivoted at a rear end 23 and adapted at a forward end for releasably supporting a point bar 18, and operating mechanism (to be described) for moving the pusher arms 22 relatively to the arms 20 for tilting the point bar 18 about a longitudinal axis thereof.

The operating mechanism for the slideway-forming arms 29 conveniently comprises, FIGURES la, 1b, 6, a short arm 24 on the shaft 21 connected by a link 25 to a bell crank lever 26 on a shaft 27, this lever 26 being connected by a link 28 to a cam follower lever 29 having a cam follower 30 engaging a cam 31 on the cam shaft 7, and the cam follower 30 being shiftable onto and off the cam by a fork 32 and a control rod 33.

The operating mechanism for the pusher arms 22 conveniently comprises bell crank levers 34 on a needle bar shaft 35 and which are connected by links 36 to arms 37 secured on said shaft 27 to which is also secured an arm 38 connected by a link 39 to a cam follower lever 40 having a cam follower 41 engaging a cam 42 on the cam shaft 7, the cam follower 41 being shiftable onto and off the cam by a fork 43 and the control rod 33.

The pusher arms 22, FIGURE 2, each has a forward fork end 22a with which a latch 44 co-operates and which has a peg 45 normally riding on the associated arm 20 to hold the latch 44 clear of the fork end 22a and which is spring biased towards a position closing over the fork end 22a.

The slideway-forming arms 20 each has a slideway 20a into which the peg 45 can ride to close the latch 44, and which has a hook end 20b.

Each point bar 18 has a forward roller 18a for engaging in an associated slideway 20a and a rear peg 18b for engagement by the associated pusher arm 22.

Plain fabric would not normally be made on this machine although this can be done at any time required. Instead the machine would normally knit only rib Welts.

The first transfer mechanism 19 is adapted for picking up the rib welts produced on the machine and carrying them from the needles to the conveyor 16 which automatically receives them.

To enable this to be done and bearing in mind that at the end of each rib welt there would normally be loops on the operative alternate frame needles 1 of the main needle bar 2 and loops on the machine needles 9, loop spreader means comprising the machine needles 9 with their loop spreader elements 9a are advanced as in FIG- URE 4 and according to said specification spread their loops L which are then taken as in FIGURE 5 by the selected frame needles, so that all the loops are then on the frame needles of both frame needle bars.

At this stage, and under a timing control to be hereinafter described, the first transfer mechanism 19 operates in the following manner.

The slideway-forming arms 20, starting from the position shown in FIGURE 2 spaced from the conveyor 16, is raised by the cam 31, FIGURE 6, carrying the pusher arms 22 with them by the pegs 45, until the base of the slideways 20a strike the forward pegs 18a of the point bars 18 whereupon further raising of the arms 20 by the cam 31 raises the front edges of the point bars out of recesses such as 17a in the bracket 17 as shown in FIG- URE 6. This is accompanied by a small rearward movement of the pusher arms 22 by the cam 42 so that the rear pegs 18b of the point bars 18 are engaged in the fork ends 22a of the pusher bars 22. These pusher bars 22 are then given a forward movement by the cam 42 whereby the forward pegs 18a of the point bars 18 are pushed into the hooks b of the bars 20, and further forward movement of pusher bars 22 causes upward pivoting movement thereof and of the point bars 18 about the pegs 18b, with the point bars 18 pivoting also about the pegs 18a, as shown in broken lines in FIGURE 6. Then the cams 31, 42 operate to lower the bars 20, 22 together, with the point bars substantially vertical in crosssection as shown in FIGURE 7 until the points P box with the frame needles 1 so that on further lowering movement of the bars 20, 22 by cams 31, 42 accompanied by lowering of the needles 1 by cam 6 the loops of the last course of the welt W are transferred from the frame needles to the point P. Next the arms 20, 22 are raised by cams 31, 42 carrying the welts W with them as shown in FIGURE 8, so that, in effect the welts W are pressed off from the needles just after FIGURE 7.

Since the welts have conveniently started with a draw thread in the first course, and a second yarn is used for the remainder of the welt, the pressed off welt has extending from its starting and finishing courses separate yarn lengths Y, Y1 from separate thread carriers TCl, TC2. These yarn lengths must be severed and before severing those portions at the thread carrier side must be trapped.

For this purpose, trapper and cutter mechanism 46, FIGURE 1b, is provided in each knitting section. This mechanism, as shown in FIGURE 9, comprises a pair of horizontally spaced trapper and cutter devices 47, 48 mounted on horizontal guide rods 49, 50 which are secured at opposite ends to slide blocks 51, 52 slidably in slideways 53, 54 in end brackets 55, 56 secured to the machine frame. The blocks are operable for raising and lowering the devices 47, 48 into and out of operating position through pegs 57, 58 engaged in fork arms 59, 60 to which are connected links 61, 62 connecting them to opposite ends 63, 65 of a common arm, FIGURE '8, using shaft 64 as a pivot, and connected by a link 66 to lever 67, FIGURE 10, connected by link 68 to cam follower lever 69 having a cam follower 70 engaging a cam 71 on a cam shaft 72, the latter being driven through an electric clutch 73a with brush pick up 7312 and sprocket wheel 73, chain 74, and sprocket wheel 75 by an electric motor 76.

The devices 47, 48, FIGURE 9, are adjustably displaceable along the rods 49, 50 through links 77, 78 connecting them to blocks 79, 80 which are secured to opposite laps 81a, 81b of an endless chain 81, the blocks being guided on rods 82, 83, 83a, 84 and the chain 81 being driven on sprocket wheels 85, 86 through a universal drive connection 87 from bevel gears 88, 89, FIGURE 8, and an electric clutch 90a with brush pick up 90b and a sprocket wheel 90, chain 91, and a sprocket wheel 92 driven by said motor 76.

Each device 47, 48 is constructed as now to be described with reference to the device 48 in FIGURES 11 to 13 except that the devices are of opposite hand. Referring to FIGURE 11, there is a block 93 slidable on said rods 49, 50 and having an upper stationary trapper arm 94. On the block 93 a movable trapper slide 95 is slidable vertically in a slot 96 in the block through a peg 97 engaged in a cam slot 98 of a cam plate 99 which is pivoted at 100 to the block 93 and carries an upper cutter knife 101. This plate is pivotally displaceable through a peg 102 engaged in a slot 103 in an extension 78a of the link 78 which is pivoted to the block at 78b. Upon pivotal movement of the link 78 the cam plate 99 carries the slot 98 riding against the peg 97 to move the movable trapper slide 95 up to the trapper arm 94, FIGURE 12, and upon further pivotal movement of the link 78, the cam plate 99 carries the cutter knife 101 past the closed trapper arm and slide as shown in FIGURE 13.

In general operation of the trapper and cutter mechanism, the trapper and cutter devices 47, 48 are, at the stage of FIGURE 7, in a down position trapping yarn lengths left after a previously made welt. When the stage of FIGURE 8 is reached, the motor 76 operates (through timing means to be described) so that cam 71 operates to raise arms 59, 60 to raise the devices 47, 48 to the level shown in FIGURE 9 but with the devices 47, 48 in their innermost position between the yarn lengths Y, Y1. Then the chain 81 operates to move the devices 47, 48 out wards so that the yarn lengths Y, Y1 become engaged between the open trapper arm and slides such as 94, 95 whereafter the chain stops. Then the cam 71 re-lowers the arms 59, 60 which not only lowers the arms 59, 60 which not only lowers the devices 47, 48 but also, through the consequent pivotal operation of the link extensions such as 78a, as shown in FIGURES 11 to 13, swings the cam plates such as 99 to raise the trapper slide 95 for trapping the yarns, followed by operation of the cutter knife 101 to cut the trapped yarns at the fabric side thereof leaving the yarns at the thread carrier side trapped.

Following the press-off stage just after FIGURE 7 and the trapping and cutting, the arms 20, 22 are operated by the cams 31, 42 in reverse i.e first to be raised from the position just after FIGURE 7 to the position shown in FIGURE 8, then to be further raised to the position of FIGURE 6, in association with the conveyor brackets 17, 17a, followed by retraction of the pusher arms 22 to the position of FIGURE 2 whereat the point bar 18 is returned to the conveyor as shown in FIGURE 2.

Next the conveyor 16 is operated through a gear box 16a, FIGURE lb, a chain 16b, and a motor 16c, to convey the loaded point bars 18 to the end of the machine from where they can be unloaded, conveniently by an automatic unloading machine shown in FIGURES 16 to 18.

Referring to FIGURE 16 there is a second transfer mechanism substantially the same as that hereinbefore described, comprising slideway-forming bars with slideway 120a and hook end 1201;, and pusher arms 122 with fork ends 122a and spring latches 123 with pegs 123a. The arms 120 are operated through arms 12 4 on shaft 125 connected by link 126 to a cam follower lever 127, 129 on shaft 128, with cam follower 130 engaging a cam 131 on a cam shaft 132. The arms 122 are operated through arms 133 on shaft 134 having a cam follower arm 135 with cam follower 136 engaging a cam 137 on the shaft 132.

The cam shaft 132 is operated through a gear 138 thereon, a pinion 139 and sprocket wheel 140, a chain 141, a sprocket wheel 142, a reduction gear box 143, and a clutch 144 connected by pulley 145, belt 146, and 147 to a motor 148.

Also provided is a stationary mounting bracket 149 secured to a machine rail 150 and mounting in removable manner a transfer point bar 151 having points 152 directed towards the conveyor, and a third transfer mechanism comprising a comb of blade elements 153, FIGURE 17, carried by a mounting 154 which is horizontally operated through a link 155 connected to a cam follower lever 156, FIGURE 16, having a cam follower 157 engaging a cam 158 on the cam shaft 132, and is vertically operated through a link 159a connected to a cam follower lever 159 having a cam follower 160 engaging a cam 161 on the cam shaft 132.

In operation of this transfer machine, and each time the conveyor 16 presents a loaded point bar 18 to the transfer machine, first the arms 120, 122 are raised by the cam 131 to the position shown in broken lines whereat the point bar 18 is raised out of the conveyor bracket recess 17a. Then the pusher arm 122 is advanced by cam 137 to hook onto the rear pegs 18b of the point bar and to engage the forward peg 18a in the hook end 12012 of the arm 120, but this time with the point bar remaining substantially horizontal in cross section, as allowed by the hook end 12% being longer than in the bar 20. This also provides for the point bar being so far advanced as to be clear of the brackets 17. The bars 120, 122 are then lowered by cam 131 until the points P of the point bar 18 box with the points 152 of the transfer point bar 151.

Next the comb of blades 153 of the third transfer mechanism is operated by cams 158, 161 for the blades to advance, descend, FIGURE 17, and retract, carrying the fabric welt from the points P onto the points 152, as shown in broken lines, whereupon the arms 120, 122 are returned by the cams 131, 137, this cycle of operations being repeated for the four fabric welts from the four knitting sections of the main machine so that all these welts are transferred onto the points 152.

Evidently there may be any other suitable number of knitting sections, and any suitable number of welts may be loaded onto the points 152, whereupon the transfer point bar 151 is removed from the transfer machine to be taken to a plain knitting machine for plain fabrics to be knitted onto the welts in turn. The conveyor is returned for repeat operation.

For timing of the various operations there is a revolution timer motor TM, FIGURE 15, various electric switches to be hereinafter referred to, and the conveyor motor is of variable speed forward and reverse type.

Certain of the electric switches are shown in FIG- URE 14 and they are disposed in the electric circuit of FIGURE 15.

Referring to FIGURE 14 each conveyor section S1, S2, S3, S4 has an electric switch actuator 162, 163, 164, 165 and the right hand section S4 has a second actuator 166. With this latter actuator is associated an electric stop switch M2, and at the left hand end of the conveyor where the loader or transfer machine is situated are an electric conveyor trip switch M3, a conveyor stop switch MS, a fast/slow switch M6 for operation by actuators 162 to 165, and a conveyor reverse switch M7 for operation by actuator 166.

Referring to FIGURE 15 the electric circuit includes the switches M2, M3, M5, M6 and M7, and also a switch M1 which is operated from the usual top disc control shaft on the machine, a cam shaft stop switch M4 operated from the cam shaft 132, forward and reverse relays FR, RR for the conveyor motor 160, relays AR, BR ER with contacts ARl, BRl ER2, and relays C1 to C3 for the cam shaft clutch 144, a fast speed conveyor clutch, and a slow speed conveyor clutch respectively.

Operation of the electric circuit is as follows:

(1) Operation is started by microswitch M1 being closed by top disc which energises relay AR closing contact ARl.

(2) Conveyor is driven through fast speed clutch relay (3) As soon as conveyor moves, it closes microswitch M2, so that top disc may continue racking.

(4) Conveyor trips microswitch M3 which closes relay BR which is retained by contact BRl. Changeover contact BR2 moves to top position.

(5) Conveyor trips microswitch M6 which closes relay DR which is retained by contact DRl. Contact DR2 opens releasing fast speed clutch relay C2 and contact DR3 closes operating slow speed clutch relay C3.

(6) Conveyor trips stop microswitch M5 energising cam shaft clutch relay C1. Conveyor slow speed clutch relay C3 is de-energised as is relay DR, contacts on this relay being reset.

(7) As soon as ca-m shaft turns it operates microswitch M4 which operates relay CR. Contact CR1 is opened which releases relay BR and changeover contact BR2 returns to bottom position. Also changeover contact CR2 moves to top position.

(8) After completing one revolution, the cam shaft opens microswitch M4 which de-energises relay CR, which closes contact CR1 and brings contact CR2 to bottom position. This stops the cam shaft revolving by deenergising clutch relay C1 and re-starts the conveyor via fast speed clutch C2.

(9) The above is repeated for a total of four cycles or 8 other number according to the number of knitting sections.

(10) After the fourth cycle, the last conveyor carriage closes microswitch M7. Its motion is then reversed by means of relay ER and the forward and reverse contactors.

(11) On reaching final position, microswitch M2 is opened, stopping the conveyor, and resetting relay ER for selection of forward contactor at the beginning of the next sequence.

It is usual in other machines between the times of producing a rib welt and the time of transferring it to the needles of a plain knitting machine, to effect loop doubling. That is to say, since the number of wales in the rib welt is greater than the number of wales in the plain fabric to be knitted onto the rib welt, it is usual to inter-transfer adjacent loops (forming double loops) at spaced intervals across the rib welts thereby to reduce the number of adjacent loops in the last course to the same number as the number of loops required in the first course of the plain fabric. This doubling is usually done by hand and it is a long and tedious process involving high labour costs.

When in the present machine, the loops from the machine needles have been transferred after the last rib course has been formed, to the frame needles, this presents an ideal stage for loop doubling to be effected, and conveniently this is accomplished automatically by the narrowing head mechanism disclosed in US. patent application No. 512,259 to which reference is directed for full details thereby saving labour and costs.

In this event it is necessary when, during a fashioning motion of the machine, the rib welts are being transferred to the point bars 18, for the narrowing head to be propped up out of operation, and also, during the loop doubling, for the arms 20, 22 to be propped out of operation. For this purpose the usual narrowing head cam follower lever 167, FIGURE 6, connected by usual link 167b to the narrowing head, has a notch 167a to be releasably engaged by a pivoted prop 168 connected by a link 169 to a bell crank lever 170 which is connected to a bell crank lever 17% which is connected by link 171 to an arm 172 on a shaft 17211. This shaft also has on it an arm 173a from which a link 173 extends, FIGURE 18, to a lever 174 which is operated, through a link 175 connected to a bell crank lever 176 and an arm 177, by a cam follower lever 178 having a cam follower 179 engaging a cam 180 on the main cam shaft 7. The arm 177 has a releasably hooked connection 177a with the cam follower lever 178, the connection being made when required for cam 180 to insert the prop 168, FIGURE 6, under the cam follower lever 167 for propping the narrowing head out, through a link 181, FIGURE 18, connected to a bell crank lever 182 which is connected by a link 183 to a control lever 184 engaging a control disc 185 on the top disc control shaft TCS.

The shaft 172a, FIGURE 6, also has arms 29a, 40a under props 29b, 40b, for propping behind cam follower levers 29, 40 to prop out the arms 20, 22 under control of the control disc 185, it being understood that the top disc control shaft TCS is racked in usual manner through racking means 186, FIGURE la, connected by link 187 to a cam follower lever 188 having a cam 189 engaging a cam 190 on the main cam shaft 7. The shaft 172a further has arm 191 connected by link 192 to bell crank 170a, and this bell crank together with bell crank 17% operate the control rod 33 for control of the cam followers 30, 41 for the arms 20, 22.

The complete sequence of operations for the machine can be summarized as follows:

(1) Knit a welt of rib fabric. (2) Change from rib to plain for the last course and renderthread carriers inoperative.

(3) Top disc control shaft operates to introduce loop doubling mechanism.

(4) During operations 1 to 3 the conveyor is standing with point bars in a position over the knitting heads but inoperative.

(5) Top disc control shaft operates to select shogging of trucks to introduce the main transfer mechanising during which the narrowing machine is propped out of action by operation of the top disc control shaft.

(6) While in the course cycle (but without knitting) transfer bars lift the point bars out of the conveyor and then they are advanced and pivoted to take up positions normally occupied by fashion transfer points.

(7) The point bars are lowered to box with the needles and, in a normal fashioning motion, the ribs are transferred from the needles to the point bars.

(8) The top disc control shaft operates to introduce a timer motor, which stops the machine.

(9) The timer motor introduces the trapper and cutter motor, and for operating a cam to raise the trapper and cutter.

(10) The timer motor introduces a clutch for the motor to traverse the trapper and cutter and to disengage the clutch to stop the traverse.

(11) The cam then operates to lower the trapper and cutter which automatically operates to trap the yarn to the carrier, and to sever the yarn to the fabric.

(12) The timer motor operates to re-start the machine and for the timer motor to stop.

(13) Course cams operate for the transfer bars to carry the point bars, with ribs thereon, back to the conveyor.

(14) The top disc shaft operates to start the conveyor through clutch means at full speed, it also starts the transfer machine motor while a draw thread is being laid for the next welt to be rib knitted, during which the transfer machine clutch is disengaged.

( 15) Draw off means are hooked up to the new rib Welt.

During the conveyor traverse, the left hand carriage operates a switch to bring in a slow clutch and to switch off the fast clutch, and it also operates a stop switch to stop the conveyor.

( 16) The transfer machine clutch is engaged to start the transfer machine.

( 17) Transfer machine cams operate to transfer rib from point to transfer bar.

(18) Camshaft operates switch to re-start conveyor.

( l9) Cam shaft clutch is disengaged.

(20) After four operations (or an number equal to the particular number of knitting sections in the machine), the last carriage operates conveyor reversing switch for return of conveyor.

The machine may be readily adapted for the fabric to be of full or half cardigan construction.

Although particular reference has been made to rib welts it is possible with this machine for it to make turned welts which may be then received on the point bars for automatic transporting by the conveyor to the delivery station.

What we claim is:

1. A straight bar knitting machine comprising in combination a plurality of knitting sections, a row of needles in each knitting section, cam operated means for operating the needles to produce knitted fabric welts in succession, a point bar in each knitting section, cam operated means for operating the point bar in co-operation with operations of the needles to automatically transfer a welt at the end of its production from the needles to the associ' ated point bar, a conveyor extending along the machine, means adapting the conveyor to removably hold point bars, means for operating the conveyor to traverse between the knitting sections and a delivery station, a transfer mechanism in each knitting section, and means for operating the transfer mechanism at an inner position to automatically receive the associated loaded point bar and at an outer position to co-operate with the conveyor in automatically transferring the loaded point bars to the conveyor for transportation thereby automatically to the delivery station.

2. A machine as claimed in claim 1 being a straight bar rib knitting machine and having machine and frame needles in each knitting section, cam operated means for operating the machine and frame needles to produce rib welts, loop spreader means in each knitting section, means for operating the loop spreader means to transfer loops from the machine needles to the frame needles, and operating means for operating the transfer mechanism to .operate the point bar in co-operation with operations of the frame needles to transfer a welt at the end of its production from the frame needles to the associated point bar.

3. A machine as claimed in claim 1 having at the delivery station a transfer bar loading machine having a magazine point bar, a second transfer mechanism for transferring the loaded point bars from the conveyor t0 the loading machine, and a third transfer means for transferring welts from the loaded point bars successively to the magazine point bar.

4. A multisection straight bar knitting machine having a plurality of knitting sections, frame and machine needles in each section, loop spreader means in each knitting section for transferring loops from the machine needles to the frame needles, first transfer means in each knitting section for transferring the welts from the frame needles to point bars and transferring the loaded point bars to a conveyor extending along the machine, a transfer bar loading machine, a second transfer mechanism for transferring the point bars from the conveyor to the loading machine, a magazine point bar in the loading machine, and a third transfer means for transferring the welts from the loaded point bars to the magazine point bar.

5. A machine as claimed in claim 4 having displaceable groups of transfer points, and means for operating these transfer points in co-operation with operation of the frame needles to effect loop doubling.

6. A machine according to claim 1 having hook up tension means, and means for operating the hook up tension means to engage with the welts during initial stages of their production and released therefrom at the end of their production.

7. A machine as claimed in claim 2 having means for effecting color changes and means for changing the rib dimensions.

References Cited UNITED STATES PATENTS 1,850,736 4/1932 Waechtler 66-90 2,314,742 4/ 1943 Start et al 66-148 FOREIGN PATENTS 1,279,249 11/1961 France. 1,179,258 5/1959 France.

621,934 11/1934 Germany.

940,012 4/ 1956 Germany.

MERVIN STEIN, Primary Examiner.

Images