US2068609A - Means for automatically controlling the driving mechanism of straight knitting machines - Google Patents

Description

Jan. 19, 1937. mc 2,068,609

MEANS FOR AUTOMATICALLY CONTROLLING THE DRIVING MECHANISM OF STRAIGHT KNITTING MACHINES Filed March 9, 1935 6 Sheets-Sheet l FLE- -I- IN YEN TOR.

' A TTORNEY.

Jan. 19, 1937. M. RICHTER 2,068,609 MEANS FOR AUTOMATICALLY CONTROLLING THE DRIVING MECHANISM OF STRAIGHT KNITTING MACHINES File'd March 9, 1955 6 Sheets-Sheet 2 FILE- E.

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Z I! 0 .9 my; 721 I 70 WW I 6.9 f a 75 ATTORN Q Jan. 19, 1937. M. RICHTER 2,068,609

MEANS FOR AUTOMATICALLY CONTROLLING THE DRIVING MECHANISM OF STRAIGHT KNITTING MACHINES Filed March 9, 1955' 6 Sheets Sheet 3 A TTORNEY.

Jan. 19, 1937. M. RICHTER 2,068,609

MEANS FOR AUTOMATICALLY CONTROLLING THE DRIVING MECHANISM OF STRAIGHT KNITTING MACHINES Filed March 9, 1955 6 Sheets$heet 4 PLE- -5- 17 INVENTOR.

' hi5? BY g M i ATTORNE Jan. 19, 1937. RICHTER 2,068,609

MEANS FOR AUTOMATICALLY CONTROLLING THE DRIVING MECHANISM OF STRAIGHT KNITTING MACHINES Filed March 9, 1935 6 Sheets-Sheet 5 I INIfENTOR. 20! 1712106 I} Jan. 19, 1937. M. RICHTER 2,068,609

MEANS FOR AUTOMATICALLY CONTROLLING THE DRIVING I MECHANISM OF STRAIGHT KNITTING MACHINES 6 Sheets-Sheet 6 Filed March 9, 1935 IIYVENTOR: Jlfaasflwhfiir, BY 6 g WATTORN Patented Janus.o lg, 1937 EZEEANS FOR AUTOMATIfiALLY CONTROL- LING THE DRIVING MECHANISM OF STRAIGHT KNKTTING MACHINES lii'ax Richter, West Reading, Pa., assignor to Textile Machine Works, Wyomissing, Pa, a corporation of Pennsylvania Application March 9, 1935, Serial No. 10,171

12 Claims.

My invention relates to means for controlling the rate of operation of knitting machines, and particularly to means for automatically controlling a variable-speed driving mechanism for straight or full-fashioned knitting machines.

A iulhfashioned stocking ordinarily comprises successively knitted areas of different weights and patterns requiring the knitting machine to be operated at diiierent speeds, as in knitting the welt, the main leg portion, and the plated portions of the leg or heel; a variable-speed brush-shifting motor ordinarily being included as standard equipment in which the brushes are shifted manually relative to the commutator to eifect the desired variations in the rate of operation of the machine. However, because such manual operations are not always effected correctly, and depend upon the skill or aptitude of the operator, the value of the variable-speed driving mechanism is considerably diminished.

It is therefore, among the objects of the invention to eliminate the human factor as to the selection of operating speeds of a full-fashioned knitting machine and, so far as such speeds are concerned, to render such machine fully automatic in the production of a stocking unit.

Acomplete cycle oi machineoperation, in producing a stocking blank of a certain type, includes operating the machine at an intermediate speed during the knitting of the welt, at a high speed during the knitting of the leg portion proper and at a slow speed during the knitting of reinforced or plated heel areas, each of which speeds has heretofore been effected by the above-mentioned manual shifting of the drive motor brushes, and a temporary slowing of the motor speed effected, during the narrowing of plain areas in the leg portion proper, by the operation of a motor-circult control switch, without shifting the motor brushes. However, in a reinforced heel area, where the speed is reduced by shifting the brushes and is slow enough to effect narrowing, it is not necessary to operate the above-mentioned motor circuit control switch.

Another object of the invention is therefore not only to automatically vary the speed of operation or the machine in main steps, as by the abovementioned shifting of the brushes for knitting the welt, the leg and the heel, but also to have automatic temporary or auxiliary control over such adjusted main speeds, as by automatically op erating a switch, as above set forth, for operation during the narrowing of plain areas of the leg, and automatically rendering such switch inoperative or ineffective during the narrowing of a reinforced area or other area when the motor speed has already been sufficiently reduced, as by shifting the brushes.

Another object of the invention is to render a device of the above indicated character simple and durable in construction, economical to manufacture and effective in its operation.

In attaining the above-mentioned objects, a main pattern device, and an auxiliary pattern unit operated from the cam shaft, generally similar to mechanism of which I am aware, are preferably included, but, since such mechanism, as heretofore employed, is relatively inflexible and expensive as to the adjustment of the auxiliary unit to different patterns, and causes undue wear of, and has other objections relative to, linkage operating between the cam shaft and the unit, it is accordingly 9. further object to remove such objectionable features whereby the auxiliary pattern unit is rendered considerably more flexible and economical in its pattern adjustment, and

the Wear, and. other adverse features, of the linkage are removed.

With these and other objects in View, which will become apparent from the following descrip- Fig. 2 is a view, similar to a portion of Fig. 1,

showing the mechanism employed to actuate the controlshaft by which the mechanism of the invention is operated;

Fig. 3 is an end view of a variable speed motor, with the invention applied thereto;

Fig. 4 shows a structure in which various rotating shafts of the machine are connected to,

electrical parts and circuits to the apparatus of the invention at one knitting speed;

Figs. 8 to 11, inclusive, are diagrams, each corresponding to a portion of Fig. 7, showing the circuits and relation of parts at successive stages of knitting a full-fashioned stocking; and

Fig. 12 is a diagram of the leg blank of a fullfashioned stocking, together with a pattern chain, as developed or opened out along a straight line in side elevation from its normally looped shape, indicating the areas along the blank in which the speeds of operation are changed, and the corre- .sponding links of the chain by which such changes are effected.

The figures disclose various parts of a Reading full fashioned knitting machine embodying the mechanism and elements of my invention, in which, for clearness, only those parts of the various mechanisms necessary for an understanding of the invention are illustrated; the various other parts and mechanisms, and the manner of operation thereof, being well known in the art, as shown and described in the Reading Full Fashioned Knitting Machine Catalogue, copyright 1929, and published by the Textile Machine Works, Reading, Pennsylvania.

Referring to the drawings, frame members I0, upon which shafts, including a cam shaft I2, are supported, also support front and back rails I3 and I4, front and center beds I3 and I3, and a member I"! which supports an auxiliary-unit control shaft I8, as shown in Fig. 2. The transverse members I3, I4, I3, I3 and I1, with the frames I0, constitute a structure for supporting the operating mechanism proper of a usual full fashioned knitting machine.

Needles I9 are operated in a usual manner by needle and presser levers 20 and 22, respectively, which are actuated by cams fixed to the cam shaft I2. Sinkers 23 and dividers 24 cooperate with the needles I9; the sinkers 23 receiving forward movement from jacks 25, which are slurred forward by slur cams 23 carried by cock boxes 21. The cock boxes are reciprocably mounted on a cock box bar 28. The rearward travel of the sinkers 23, and the forward and rearward movement of the dividers 24, are effected by a catch bar 29, which is operated by a back catch shaft 30, through means of vertical and horizontal shifter arms 32 and 33, respectively, connected to the shaft 30 and to the catch bar 29, as shown. The back catch shaft 30 is actuated by a lever 34, fixed thereto, a cam follower 33 of which engages, and is operated by, a cam carried by the cam shaft I2. The follower 35 is held in yielding engagement with its respective cam member by means of a coil spring 33 that is hooked to the free end of the lever 34, and anchored to the front rail I3, by a hook member 31. A lever 38, secured to the bar 29, operates to move the catch bar 29 into and out of engagement with the sinkers 23. The lever 38 is raised and lowered by a front catch shaft 39 through a linkage including a lifting arm 40 and a lifting lever 42. A roller 43 rotatably mounted on a lever 44, secured to the shaft 33, is operated by a cam on the cam shaft I2.

A front narrowing shaft 43, which carries brackets 48 for supporting narrowing rods 41, to which narrowing fingers 43 are secured, is maintained in parallel relation to a back narrowing shaft 49 by intermediate guide arms 30. Arcuate movement of the shaft 43 relative to bearings 32 is effected by a cam on the cam shaft I2, transmitted to the shaft 43 through a cam follower 33 rotatably mounted on a narrowing lifting lever 34. The lever 34 is pivotally mounted on a pin 33 that is supported by the stationary frame. The lever 34 is also connected to the front narrowing shaft 43 by a link 33.

A motor M, by which the knitting machine is actuated, is supported by a bracket 31 secured to the rail members I3 and I4, as shown in Figs.

l and 4. A sprocket wheel 58, attached to a hand wheel shaft 59, is rotated by a chain 30, which is driven by the motor M. A second sprocket wheel 32, on the hand wheel shaft 39, rotates a drive shaft 33 through a chain 34, and a sprocket 35 on the shaft 33. A pinion II, that is disposed on the shaft 33, drives a gear wheel 83 which is secured to the cam shaft I2.

The auxiliary-unit control shaft I8, see Fig. 2, by which the various auxiliary-pattern-unit control chains, such as a brush-shifting chain 83, are intermittently actuated, receives its motion from a cam 3i, when a supporting lever I is moved from beneath a lever IOI, thereby permitting a roller I02 to follow the contour of a cam BI. The lever I00 is thus moved by buttons on the conventional main pattem-chain unit or device C, as indicated diagrammatically in Fig; 7. This action transmits oscillatory movement to a member I03, freely mounted on the control shaft by means of an intermediate link I04, whereupon a pawl I operates a ratchet wheel I03 secured to the control shaft. A toothed member 31, held in yielding engagement with the ratchet wheel I03 by a spring 38, locks the control shaft II against reverse rotation between the intermittent operations of the pawl I03.

The above-described mechanism, as best seen in Fig. 2, wherein there is a linkage including the member I03, the link I04 and the lever IOI, between'the auxiliary pattern unit, including the chain 83, and the cam shaft I2, is, as heretofore stated, generally similar to a prior mechanism which however, does not have a single-link connection similar to that including the link I04, and does not have a follower-and-cam arrangement similar to that hereof, wherein the follower I02 periodically engages and dlsengages the cam 6|. constantly engaged to and operated by, the cam shaft, the continuous motion of which is transmitted, by onelinkage, to a position at the aux- Instead, the prior device has an eccentric iliary unit for control, by a second linkage from the main pattern device, to periodically operate the unit, thus including unnecessary structure, occupying undue space, being more expensive. causing unnecessary wear and vibration, and having other disadvantages. Applicant's device reduces this two-linkage arrangement to a single linkage, and removes the constant1y-operating linkage, with the advantages manifestly resulting therefrom, which, in combination with the other elements herein set forth, produces an automatic speed-varying mechanism for a straight or full-fashioned knitting machine whereby such machine is substantially improved.

The motor M, preferably of the alternatingcurrent type having shunt characteristics, and which is ordinarily employed to operate a full fashioned knitting machine, has its speed selectively changed by shiftingbrushes 39 of a commutator 10. The brushes are connected, respectively, to independent phase windings of the stator S, see Fig. 7, and heretofore, have been shifted manually.

.Referring to Fig. 3, brush-shifting means operate upon two segmental brush- holder yokes 12 and 13, each of which carries a pair of brushes 39 for contract with the commutator I0. The yokes are .movable toward and from each other peripherally of the commutator, and are pivtill tary discs it and 715, which are carried by, and are freely turnahle on, the motor shaft 56.

To simultaneously move the brushes, an operating member it is provided, which carries a pin it, fixed to its low-er end, and is loosely connected to links it and. to, Figs. 3 and 4, which are pivotally connected to the discs 'M and 15, respectively. The brush operating member 'll has a slot 82, through which extends a pivot bolt 83 secured to the motor casing. A plate 84, for supporting the member ll and which is loolted to the motor casing, has an arcuate cam slot 85, through which the pin 18 extends, and in which the pin moves, when the operating member it is turned in either direction to shift the brushes. The slot 82, in the operating member ll, permits free longitudinal movement of the latter, when the pin 18 moves in the cam slot 35.

To automatically change the setting of the brushes for regulating the speed of the motor, a control chain 36 is operatively disposed between an idler pulley ti and an actuator wheel ht on. the control shaft iii. Supported by the transverse bar [1, is a bracket t9 by which a lever Qt is pivotally carried. The lever is connected to the operating member Tl, by an intermediate link 92, as shown in Figs. 3 and 4. A chain follower V 93, rotatahly mounted on the leverttl, is held in yielding engagement with the control chain, by

means of the tensioning action oi a spring or attached to the hook end of the lever to, and

anchored, at its opposite end, to the back rail l4 byv a hook clamp 95. This structure permits operation of the member il, in accordance with of plating full fashioned hosiery. The motor is operated at high speed, during the fabrication of the main leg portion, when a low link 86?) is moved to position as in Fig. 4, by which action the pin it is moved to the opposite end of the arcuate slot 85, and the brushes are correspondingly repositioned. Uperation or the machine, at medium speed, is eflected by movement of a link 85c, of medium size, to a position beneath the roller til. Medium speed is employed during the knitting of certain areas, as in the welt por tion of a stocking. Any desired number of speeds is obtainable by the employment of chain links of various heights.

During the knitting of an unreinforced portion of a stocking, such as the main leg portion, the machine is normally operated at a high speed. To provide tor the production of narrowing stitches in such unreinforced portion, the speed of rotation of the cam shaft l2, while in its shifted or narrowing position, must be reduced. To produce this result, a speed reducing switch 99, illustrated diagrammatically in Figs. 7 to 11, inclusive, is operated, by inwns associated with a main chain motion mechanism (3, when the cam shaft is axially shifted.

However, during the formation of plated areas, the speed of operation of the machine is appreciably slower than the speed at which it is operated while knitting unreinforced fabric, and consequently, does not require an additional reduction of speed, or to be affected by the speedreducing switch, when narrowing the plated por tions. Therefore, to nullify the efiect of the speed reducing switch, while the machine is already opone e39 crating at a sumciently low speed, a safety switch H, see Figs. 1, 4 and 6, is included the circuit of the speed-reducing switch. The switch It is normally closed when the machine is operating at a high rate of speed, as when the low links etc of the control chain tt are positioned as in Fig. l. However, with the high links the in such position, and the resultant reduction of the motor speed, a stud 96, carried by the brush shifting lever ill, coacts with a spring til to move a rod to. This action opens the safety switch ii to open the circuit of the speed reducing switch 99;, there= by isolating the speed reducing switch, and preventing any eifect thereby on the rate oi speed of the motor.

When the low cam links ttb move to the position indicated in Fig. i, the brush shifting lever "l'i will be retracted, whereupon the switch H will again be closed, and the speed reducing switch reconditioned, relative to the motor cir-= cuit, to afiect the latter when the cam shaft is shifted to its narrowing position in a plain-knit course.

The above-described, operation may be better understood from a consideration of Figs. '3 to 12,

inclusive, in Fig. 7 of which, the motor M is shown as comprising a three phase rotor Roonnected to supply-line conductors 2&2, 2% and 2M, and mounted on a shaft 2%, also carrying an excitation winding E, and the commutator ill connected to the winding E, in conventional manner.

It is to be understood that a master switch may be connected to the supply lines at any suit able position, or in conductors it]? which connect the supply lines to the rotor R through slip rings.

The stator S, supplied from the excitation winding E, through the commutator iii and the brushes 69, comprises separate coils its and its. Resistors H0 and i H are adapted to be thrown into, and shunted from, the stator circuits as by switches IM and lit, respectively, connected to a common actuator ill. The latter is biased, as by a spring H8, to hold the switches M l and H5 in the open positions indicated, in the deenergized condition of a solenoid H9, in which position, the resistors lit and H2 are shunted out of the circuits of the stator coils W8 and Mill.

The solenoid H9 is connected across the supply lines 202 and its by a conductor 92!), in cluding the safety switch and by a conductor 622, including the speed-reducing switch 9t, and a push-button switch (123. The switch H is connected, as above set forth, by the rod 98, to the brush-shifting lever 9t, which is operated by links on the auxiliary control chain lit. The

switch 99 is adapted for operation by buttons on the welt line H?) and, in its open state, before folding over on the edge ltd, as bounded by the course H6 and the welt line 525.

The links of the control chain 86 determine the speed sequence at which the machine is operated during the production of a stocking leg blank. The control chain 8% controls the speed of the machine from a line Mi, in advance oi the first course Wt knitted in the welt, to the last courses I42 of the blank at the ends of the heel tabs I34.

Prior to starting the first course I26, the control chain 86 is operated from a low speed button 86a to an intermediate speed button 860, for a distance corresponding to a distance I43, which extends from the line I4I to the course I26, to shift the brushes 69 from a low speed position to an intermediate speed position. The intermediate-speed position is maintained for a distance corresponding to the distance I45, which extends from the course I25 to a course I46.

During this operation, the parts are as indi cated in Fig. '7, in which the resistors H2 and H are shunted out of the circuits of the stator windings, the switches H and I23 are closed, and the switch 99 is open.

At thecourse I46, the control chain is again operated, a high speed link 86b shifting the brushes 69 of the motor M, as above set forth and as indicated by the relation of the parts in Fig. 8; this action immediately stepping up the speed of the motor, but leaving the switch 'H closed, and the switch 99 open, whereby the switches H4 and H5 remain open, and the resistors H0 and H2 are still shunted out of the stator-coil circuits. This position of the parts is maintained for a distance on the blank corresponding to a distance I41, which extends from the course, I46 to a course I48.

At the course I48, the control chain is again operated, an intermediate speed link 06c shifting the brushes 69, through the lever 90, as indicated in Fig. 7, this action immediately reducing the speed 01 the motor, so as to draw the carriers of the alternating mechanism, (not shown), into the knitting field. This position is maintained 1" or a distance I50. which extends from the course I43 to the course I21.

As stated above, the machine then operates, in general, at its high rate of speed in each course for a distance I5I which ext-ends from the course I21 to the course I33, operating at high speed throughout each course.

In courses where the fashioning points are to be inserted, for forming narrower courses, which occurs after a course is produced, the machine is operated at a reducedspeed. These reductions of the high speed, occurring in a distance I52, which extends from the course I21 to a course I20, and in the distance I53 extending from the line I to the line I32, are accomplished by buttons on the main pattern control chain C, which buttons momentarily close the switch 99.

When the switch 99 is so closed, it completes the circuit of the solenoid H9 from the supplyline conductors 202 and 203, through the switches H and I23, to move the actuator II1 against the action of the spring H8, and to thereby close the switches H4 and H5. This action inserts the resistors I I0 and I I2 into the circuits of the stator windings I08 and I09, respectively, whereby to reduce the speed of the motor, without changing the positions of the brushes 69 from the highspeed positions thereof, as indicated in Fig. 8.

At the course I33, at which plating begins, a

' slow-speed link 86a of the auxiliary control chain 03 moves the lever the positions of the parts indicated in Fig. 1 This action shifts the brushes 69 of the motor M to positions in which the motor operates at a slow, or plating speed, and simultaneously opens the switch H, which up to this time has remained closed throughout the knitting of the welt W and the leg L. This position of the parts is maintained for a distance I52, which extends from the course I33 to the course I42 of the heel tabs I34. The speed corresponding to this position, being suificiently slow for both plating and fashioning, it is not necessary to further change the speed at the narrowing courses, so that, a button on the main control chain 0, which normally is operative to effect both the fashioning action and a slowing of the speed for such action, is operative only to effect the fashioning action, since, when it closes the switch 99, as indicated in Fig. 11, the switch H is open, and the solenoid H9 is not energized. Thus, when during the knitting of the heel tabs I34, it is necessary to effect narrowing operation, for a distance I54 which extends from the course I36 to the course I31, the speed is not changed at the narrowing courses.

Obviously, many other combinations of links, pattern mechanisms and other elements, as well as other variable-speed motor drive means, may

be devised and operated in accordance with the invention, to obtain various combinations of knit-- ting speeds in accordance with any desired pattern, weight of thread or other feature.

The improvements specifically shown and described, by which the above-described results are obtained, may be modified in various ways without departing from the spirit and scope of the invention as herein disclosed and claimed.

I claim:

1. A full-fashioned knitting machine including a variable-speed drive mechanism, control means therefor, a cam shaft for operation by the drive mechanism, means responsive to axial shifting of the cam shaft for affecting the speed of the drive mechanism, means for governing the operation of said speed affecting means, and pat tern means for simultaneously operating said control and said governing means.

2. A knitting machine comprising knitting mechanism, pattern mechanism, means for actuating the knitting mechanism to knit a fabric continuously through a plurality of areas in which the knitting mechanism is operated at different rates, means automatically operative in accordance with operation of the pattern mechanism for varying the rate of operation or the actuating means during the patterning of an area thereby, and means automatically responsive to operation of the machine for varying the rate of operation of the actuating means, and nullifying the effect of said first automatic means, during the patterning of another area by the pattern mechanism.

3. A full-fashioned knitting machine comprising knitting mechanism, narrowing mechanism, means for actuating the knitting mechanism to knit a stocking blank continuously through a plurality of areas in which the knitting mechanism is operated at different rates, means automatically operative in accordance with operation of the narrowing mechanism for varying the rate of operation of the actuating means during narrowing of a plain area, and means automatically operative in accordance with knitting movement of the blank for varying the rate of operation of the actuating means during the knitting of a plated area and nullifying the effect of said first automatic means during the narrowing of a plated area. i

4. In a knitting machine, actuating means including a brush-shifting motor, an auxiliary pattern unit for shifting the brushes of the motor, resistor means, and a main pattern unit for i controlling the insertion of the resistor means into the stator circuit of the motor and the withdrawal oi the resistor means from the stator circult to affect the speed of the motor independently of the brushes.

5. In a knitting machine, loop-forming mechanism, actuating means including a three-phase alternating-current motor embodying a stator, a commutator and shiftable brushes for the commutator, a resistor, a switch for inserting the resistor into, and excluding it from, the stator circuit, pattern mechanism, and means responsive to operation of the actuating means and controlled by the pattern mechanism for controlling both the shifting of the brushes and the operation 01 the switch.

6. A full-fashioned knitting machine including a drive mechanism embodying a variable-speed motor, control means therefor, a cam shaft rotated by the drive mechanism, an auxiliary shaft intermittently rotated by the cam shaft, a speed reducing switch operative by axial shifting of the cam shaft, a safety switch for controlling the operation of the speed reducing switch, and a pattern chain carried by the auxiliary shaft for simultaneously operating the variable-speed motor control means and the safety switch.

'7. In combination, in a full-fashioned knitting machine, a knitting mechanism, actuating means therefor comprising a motor including brushes shiftable tovary the rate of operation thereof, narrowing mechanism. means in the circuit of the motor and operative in accordance with operation of the narrowing mechanism for controlling the rate of operation of the motor, means for determining the rate of operation of the motor embodying means for shifting the brushes and controlling said first control means, a cam shaft, means including a cam on the shaft for actuating the brush-shifting means, and means including a pattern mechanism for controlling the actuation of said rate-determining means by the earn.

8. in a knitting machine, knitting mechanism, means including an electric motor for actuating said knitting mechanism, said motor including a commutator and brushes for the commutator, means for shifting the brushes, means for actuating said brush-shifting means to vary the speed of the motor, means for varying the speed tion winding and a commutator, a stator, means I including brushes cooperating with the commutator for connecting the excitation winding to the stator, means for shifting the brushes to vary the speed of the rotor, an auxiliary pattern unit for controlling the brush-shifting means, resistor means, switch means for throwing the resistor means into and out of the stator circuit, electro-responsive means for actuating said switch means, a switch-controlled by the brush-shifting means for opening and closingthe circuit of said electro-responsive means, a main pattern unit, and a switch controlled by the main pattern unit for opening and closing the circuit oi? said electro-responsive means.

10. In a knitting machine, an alternating-current motor including a rotor carrying an excitation winding and a commutator, a stator, means including brushes cooperating with the commutator for connecting the excitation winding to the stator, means for shifting the brushes to vary the speed of the rotor, means responsive to operation of the machine for controlling the brush-shifting means, impedance means, means for inserting the impedance means into, and

withdrawing it from, cooperative relation to the stator circuit, electro-responsive means for actuating said inserting and withdrawing means, means controlled by the brusl1-shifting means for energizing and deenergizing the circuit of said electro-responsive means, and means responsive to operation of the machine for energizing and deenergizing the circuit of said electro-responsive means.

11. In a machine for knitting a full-fashioned stocking, knitting mechanism, narrowing mechanism, actuating means including an electric motor including a commutator and brushes for the commutator, shifting of the brushes on the commutator causing the motor to operate at different speeds, pattern means, means controlled by the pattern means for shifting the motor brushes to operate the machine at an intermediate speed during the knitting of the welt, at a high speed during the knitting of the leg portion and at a slow speed during the knitting o1 reinforced or plated heel areas, means for affecting the motor circuit to control the speed of the motor independently of the brushes, and a circuit making-and-breaking device for controlling said last named means, the pattern means controlling the circuit making-and-breaking device to temporarily reduce the speed of the motor independently of the position of the brushes durarea.

12. A full-fashioned knitting machine comprising knitting mechanism, means including an electric motor for actuating the knitting mechanism .to knit a stocking blank continuously through the welt, the leg and a heel having reinforced tabs, the motor including a commutator and brushes shiftable thereon to vary the motor speed, means in the motor circuit to vary the motor speed, narrowing mechanism for operation by the actuating means, means for auto-' matically controlling the narrowing mechanisms during the knitting operation to effect successively spaced narrowing operations adjacent to the top and bottom of the leg, respectively, and in the heel, brush-control means automatically responsive to operation of the actuating means for shifting the brushes to operate the motor at an intermediate speed during the knitting of the welt, at a high speed during the knitting of the leg and at a low speed during the knitting of the heel, and means operative in accordance with operation of the narrowing mechanism for controlling said motor' circuit motor-speed varying means to operate the motor at slow speeds dur-

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