Apparatus and method for winding and doffing roll of knitted cloth on a circular knitting machine

Abstract: An automatic winding and doffing apparatus of a circular knitting machine includes a winding unit (4) that revolves synchronously with the cylinder of the circular knitting machine. The apparatus includes opposed winding apparatus frame arms (16,17). A fabric winding roll (21) has one roll end pivotally mounted on one of the arms. A guide mechanism guides the knitted fabric to the winding roll. The fabric roll is stopped after a predetermined amount of fabric has been wound. A doffing apparatus doffs the fabric from the winding roll after a predetermined amount of fabric has been wound on the fabric roll. In preferred embodiment, the other winding roll end is freely supported by a turning lever (28) pivotally mounted on the frame. Upon pivoting movement of the lever arm, the winding roller may be moved from a home, winding position to an unloading, doffing position in which the other end of the winding roller is removed from the support arm. A lock mechanism operatively connects to the turning lever for locking the turning lever in a position in which the turning lever supports the winding roller in the home, winding position and for unlocking the turning lever to allow the turning lever (28) to pivot and disengage from the winding roller (21).

Description: Field of the Invention This invention relates to an apparatus for automatic winding and doffing of knitted cloth on a circular knitting machine. (see FR-A-2 162 918) Background of the Invention In conventional circular knitting machines, knitted cloth is flattened and wound on a winding roller supported by a winding unit. The winding unit revolves synchronously with the knitting machine cylinder and drives fabric delivery rolls through power transmission mechanisms which interconnect to the rotating winding unit. The knitted fabric then is wound into a flat sheet on the winding roll positioned beneath the delivery rolls. Typically, an operator manually unlocks the winding roll from a locked position relative to the frame arms of the machine frame, and removes the winding roll from the machine, together with the knitted fabric wound on the roll. In recent years, technology advances have enabled circular knitting machines to operate at increased speeds, particularly in those knitting machines that knit fabrics in full body size. As a result of these speed increases, the knitted fabric is wound faster and doffed in shorter cycles, creating excess and difficult work for the machine operator. Summary of the Invention It is therefore an object of the present invention to provide an automatic winding and doffing apparatus and method for a circular knitting machine in which the winding and doffing steps are automatic for increasing efficiency and saving labor in delivery of the knitted fabric from the machine. In accordance with the present invention, the claimed apparatus and method provides for more automated winding and doffing of the knitted cloth. The apparatus includes a winding unit revolving synchronously with the cylinder of the circular knitting machine. The winding unit is positioned below the cylinder and drives fabric delivery rolls through a power transmission mechanism interconnecting with the rotating winding unit. A fabric winding roll is positioned between opposed frame arms of the machine and the roll winds the knitted cloth. The winding roll has two opposing ends and includes means for changing the diameter of the roll to allow a fabric wound thereon to be doffed from the roll. A plurality of combs are positioned on the surface of the roll. The combs are movable between a retracted position in which the combs are retacted and positioned below the surface of the roll to an extended position in which the combs project from the surface of the roll to engage the cloth and retain the cloth onto the winding roll. One end of the winding roll is pivotally connected to one of the frame arms. Means guides the knitted fabric onto the winding roll at the start of fabric winding. The combs catch the knitted fabric and secure the knitted fabric to the winding roll. Means stops the winding roll after a predetermined amount of knitted fabric has been wound on the winding roll. Afterward, means cuts the knitted fabric and means doffs the knitted fabric in the direction of the roll axis. In a preferred embodiment, a turning lever, pivotally mounted on the frame, supports the other free end of the winding roll so that the free end of the winding roll may be moved from a home, winding position to an unloading, doffing position in which the free end of the winding roller is moved away a support arm. Locking means is operatively connected to the turning lever for locking the turning lever in a position in which the turning lever supports the winding roller in the home, winding position and for unlocking the turning lever to allow the turning lever to pivot and disengage from the winding roll. A gate is positioned adjacent the winding unit between the frame arms for protecting and substantially covering the winding unit. Means automatically opens and closes the gate when doffing the knitted fabric from the winding roll. The winding roll includes two channel members dividing the surface of the winding roll into two half sections. Means moves the half sections relative to each other for changing the cross sectional size of the winding roll. The winding roll includes guide channel members having holes. The half-section channel members engage the guide channel members and are guided along the holes. In a preferred embodiment, the locking means includes a cam on which the turning lever abuts, and includes motor means operatively connected to the cam for rotating the cam and turning the lever arm. Brief Description of the Drawings The foregoing and other objects, features and advantages of the present invention will become apparent from the following detailed description of the preferred embodiment of the invention, and from the drawings, in which: Figure 1 is a front elevation view of the circular knitting machine in accordance with a preferred embodiment of the present invention; Figure 2 is a plan view of the knitting machine taken along line 2-2 of Figure 1; Figure 3 is a front elevation view of the winding unit of the present invention; Figure 4 is a side elevation view of the winding unit taken along line 4-4 of Figure 3; Figure 5 is a partial sectional view of the winding roll in accordance with the present invention; Figure 6 is a sectional view of the winding roll taken along line 6-6 of Figure 5; Figure 7 is a sectional view of the winding roll taken along line 7-7 of Figure 5; Figure 8 is a diagrammatic, partial sectional view of the turning lever and the locking and unlocking mechanism for locking the free end of the winding roll with the turning lever; Figure 9 is a sectional view of the lever arm taken along line 8-8 of Figure 8; Figure 10 is a sectional view of the fabric guide apparatus taken along line 10-10 of Figure 3; Figure 11 is a plan view of the winding unit taken along line 11-11 of Figure 3; Figure 12 is a partial sectional view of a portion of the fabric doffing mechanism and the fabric cutting mechanism; Figure 13 is a sectional view taken along line 13-13 of Figure 12; Figure 14 is a plan view of a switch used for stopping the winding roll after a predetermined amount of fabric has been wound thereon; Figure 15 is a side sectional view taken along line 15-15 of Figure 14; Figure 16 is a front view of the gate opening mechanism in accordance with the present invention; Figure 17 is a diagrammatic, sectional view taken along line 16-16 of Figure 15; Figure 18 is a block diagram showing the signal transmission for controlling operation of the automatic winding and doffing apparatus of the present invention; and Figures 19 and 20 are block diagrams showing operation of the automatic fabric winding apparatus in accordance with the present invention. Detailed Description of the Preferred Embodiment Referring now to Figure 1, there is illustrated a front elevational view of a circular knitting machine in accordance with the present invention. The circular knitting machine includes a knitting unit 3 mounted on a knitting bed 2 supported by legs 1 . The legs 1 include cross members 11 extending along the bottom. A winding unit 4 (Figure 3) and drive mechanism 5 are positioned below the knitting unit. The drive mechanism 5 includes a motor 6 having a motor converter 8 with a digital panel 7 for displaying operating characteristics of the motor 6 . Below the drive mechanism 5 , an AC invertor motor control panel 9 (hereinafter referred to as "ACI motor control panel") and automatic doffer control panel 10 are positioned. Gates 12 , 13 are secured between the legs 1 . As illustrated, the gates are divided vertically in two sections, forming an upper gate, which can be opened and closed by hand, and a lower gate portion, which forms a window that can be automatically opened and closed for removing the cylindrically wound fabric positioned on the winding unit 4 . A rotatable ring gear 14 is contained in the knitting bed as shown in Figure 3. The knitting machine frame includes winding frame arms 16 , 17 that rotate synchronously with the ring gear 14 through two connecting rods 15 connected at the bottom of the gearing 14 . The winding frame arms 16 , 17 , are formed integral with each other and are fixed on the bottom frame 17' . One of the frame arms 16 is semi-circular in shape to allow the fabric wound into a cylindrical package to be removed in a horizontal direction relative to the machine (Figure 10). During knitting, the knitted fabric 18 is delivered from the knitting unit 4 by at least two lines of delivery rolls 19 , 20 , and then wound on the winding roll 21 . A contactless switch KSI positioned on the bottom of the bed 2 detects the knitting machine speed, i.e., number of revolutions. Referring now to Figures 3 and 4 , the drive mechanism 5 of the winding unit 4 will be described in greater detail. The winding unit 4 rotates and drives the delivery rolls 19 , 20 through a power transmission mechanism connected to the frame arms 16 , 17 . The power transmission mechanism includes a first bevel gear mechanism 22 that rotates as the winding unit 4 rotates. The mechanism includes a first belt 23 , a second variable speed pulley 24 , and a worm 25 that rotates the delivery roll 19 . A spur gear 26 rotates the delivery roll 20 , and a third belt 27 rotates the winding roll 21 . Referring now to Figures 5 through 7, the winding roll 21 is shown in grater detail. The winding roll is rotatably supported at one end by a bearing fitted into the frame arm 17 . The other end of the winding roll is free. During winding of knitted fabric, the free end of the winding roll is in contact with the tip of a turning lever 28 . As will be described later in detail, the turning lever 28 is released from the winding roll 21 when the fabric wound on the winding roll is removed. As shown in Figure 5, the winding roll 21 is shaped in a square configured hollow member, formed from rectangular channel members 21 , which divide the surface of the roll into two half sections. Short stub shafts 29 , 30 are fixed at the ends of the hollow cylinder, and a bearing 31 is mounted on the outer side of the short stub shaft 29 . A spring 33 is positioned between a mounting collar 32 and the periphery of the bearing 31 . A rectangular, elongated shaft 34 is positioned on the inner side opposite the short stub shafts 29 , 30 and formed integral with the body. Guide holes 34a , 34a are positioned in the shaft 34 and are inclined toward the upper right side at two positions along the same direction. Other guide holes 34b , 34b are inclined to the lower right side along the same direction as the asymmetrical, opposing surface. Combs 35 are positioned along the winding roll 21, preferably along four areas of the roll, and extend outward from the winding roll 21 . The combs 35 project from the roll, catch the tip of the fabric suspended from the knitting unit, and cause the fabric to remain secured to the winding roll 21 . When the fabric is to be doffed from the winding roll 21 , the combs 35 are retracted into the winding roll 21 . The guide holes 34a , 34b engage pins 35a secured to each comb 35 . Each comb 35 is guided by a guide plate 21c secured on each of the channel members 21a , 21b . The channel members 21a , 21b include holes 21c into which the combs 35 extend. Small channel members 21e , 21f are secured on the inside of the channel members 21a and 21b . The small channel members 21e , horizontal guide holes 21g and inclining guide holes 21h are bored to incline toward the lower right side along the same direction to each other. Channel members 21f , horizontal guide holes 21j and inclined guide holes 21k are inclined toward the lower right side along the same direction. Pins 34c extend through the elongate shaft 34 and extend into horizontal and inclining holes. When the channel members 21a , 21b are moved in the direction of the illustrated arrow in opposition to the force supplied by the spring 33 , the combs are withdrawn from the surface of the winding roll along the inclining guide holes 34a , 34b , and, as a result, the cross-sectional size of the winding roll decreases. Thus, the knitted fabric is easily removed from the winding roll in the direction of the roll axis. After the fabric wound on the winding roll is removed, the winding roll is restored to the initial position in which the combs 35 project from the roll surface to prepare for subsequent winding of the knitted fabric. Referring now to Figure 8, the turning lever supporting the free end of the winding roll 21 is illustrated in greater detail, together with the lever locking mechanism 37 , which locks and unlocks the turning lever. The turning lever 28 is mounted on the frame by a pin 36 positioned in a recess formed on the frame arm 16 . The forward portion of the turning lever 28 includes a cut-away, concave portion 28a , which supports the free end of the winding roll 21 . The other end of the turning lever 28 includes an inclined portion 28b . A spring 28c is fixed between the winding frame arm 16 and the turning lever 28 to bias the lever arm. The locking mechanism 27 is positioned on the lower end of the lever arm 28 . The locking mechanism 37 includes a cam 38 on which the turning lever 28 abuts. A collar 40 aids in supporting the cam 38 and a geared motor 39 , which is operatively connected to the cam 38 . The cam 38 is positioned at 90 degrees relative to a sensor plate 41 . When the cam 38 is rotated vertically, and turned into a position as shown by the double-dash line, knitted fabric is in position to be doffed. The cam 38 and collar 40 are positioned in a support box 42 . Two contactless switches KS11 and KS12 are positioned in the support box. The support box is mounted to a base plate. Referring now to Figure 10, there is illustrated a side view of the fabric guide mechanism 43 . The fabric guide mechanism is positioned above the frame arms 16 , 17 , and includes a fabric guide plate 44 and spring 45 for pressing the guide plate 44 onto the knitted fabric. The fabric guide plate 44 is rotatably fixed to arms 46 horizontally extending from the frame arms 16 , 17 . The fabric guide plate 44 presses against the forward end of the knitted fabric at the start of the winding, while pressing and stabilizing the wound fabric as the roll of knitted fabric diametrically enlarges. The guide plate 44 accurately moves while touching the knitted fabric in opposition to the biasing force of the spring 45 as the diameter of the wound knitted fabric roll increases. Referring now to Figure 12, the fabric doffing mechanism includes a doffing plate 49 for pressing the side of the knitted wound fabric on the winding roll 21 . A movable block 50 includes a female screw portion fixed to the doffing plate 49 and integral therewith. Screws 51 mesh with the movable block 50 . A motor 52 drives the screw 51 . Two guide bars 53 are in parallel with the screw 51 and are inserted into support frame members 54 . The movable block 50 is displaceable between support frame members 54 . A sprocket wheel 55 is secured onto one end of the screw 51 beyond the outer side of the support frame 54 . The sprocket wheel is driven by a motor 52 secured to another sprocket wheel 56 through a chain mechanism. The motor 52 is connected to a motor support frame 57 positioned on the side of the support frame 54 . A channel configured cover 58 and angle members 59 are fixed onto the sides of the support frame members 54 at upper and lower portions. Both side ends of the cover 58 and angle members 59 are shielded, such as by resilient rubber plates 60 , positioned above and below the entrance to prevent fibers from entering. The arms 50a on both sides of the movable block 50 extend upward beyond the rubber plate 60 . A vertical plate 50b is fixed on the arms 58 . The doffing plate 49 is connected to the vertical plate 50b and the forward end of the doffing plate extends within the vicinity of the winding roll 21 (Figure 4). A sensor plate 50c is connected to the side end portion of the movable block. A contactless switch KS13 detects the positional base point of the movable block 50 . A contactless switch KS14 for detecting the most extended use displacement of the block 50 is fixed opposite to the sensor plates 50c . Referring now to Figure 11, there is illustrated in greater detail the fabric cutting mechanism 48 in accordance with the present invention. The fabric cutting mechanism 48 is positioned outside the fabric doffing mechanism 47 , and includes a circular cutter portion 61 and a cutter displacement and driving mechanism 62 . The circular cutter portion 61 includes a motor 62a on which a circular cutter 62b is fixed (Figures 4 and 11). The circular cutter 62b includes a cover 63 for protecting the cutter and minimizing chance of injury. The cover 63 is supported on a bent, upright stand 64 so that the cutter member 61 is positioned close to the knitted fabric. The stand 64 is supported on the cutter displacement and driving portion 62 , which includes a movable member 65 , transmission wire belt mechanism 66 , rail member 69 and a motor 67 for moving these components. A mounting support block 68 is connected to the upper side of the bottom portion of the movable member 65 and is integral therewith. The block 68 includes pulley rollers 70 positioned at both sides so that the rail member 69 is displaceable. A power supply brush 71 is connected to the cutter portion, and a motor 67 is fixed to the rail member 69 . Wheel 73 , 74 are positioned on the rail member 69 and a pulley belt or wire 75 extends therearound. The pulley wheels 73 , 74 are connected to the motor 67 and the rail member 69 . Rotation of the pulley wheel 73 drives pulley wheel 74 and displaces the mounting support block 68 connected to the pulley wire 75 , as well as the movable block 65 . A sensor plate 65c is connected to the side end of the movable member 65 . A contactless switch KS3 detects the positional base point of the movable member 65 . A contactless switch KS4 detects the terminal point of displacement of the member fixed opposite the sensor plate 65c . Referring now to Figure 14, a plan view showing a contactless switch for stopping the winding roll and detecting the knitted fabric is illustrated. The contactless switch KS2 allows stopping of the winding roll at a fixed position. The contactless switch is connected to the side of the box 82 at a position in close proximity to the winding unit 4 . A sensor plate 83 is connected to the bottom of the winding unit 45 . A micro switch KS17 is contained in a containment box secured to the base plate. Referring now to Figure 16 and 17, details of the gate opening and closing mechanism 76 are illustrated. The gate opening and closing mechanism 76 includes a transmission motor. Below the window portion 80 , pulley wheels 77 are positioned and a pulley wire 78 extends between and around the pulley wheels. A motor 78 is fixed on one of the pulley wheels 77 , a transparent slide 81 is connected to the pulley wire. The slide 81 moves as the pulley wire moves right and left. The slide 81 is larger in size than the window portion 80 and is supported by guide rollers 82 positioned on right and left corners. A dash line drawn in the window portion of Figure 16 indicates a knitting fabric wound on the winding roll 21 . The fabric is doffed to a position shown in Figure 2 across from the window portion 80 when pushed by the doffing mechanism 47 . Afterward, the doffed fabric is conveyed by a cart, belt conveyor or the like to a position for subsequent processing. A sensor plate is integrally fixed to the slide 81 and positioned on the lower end of the slide 81 . On the plate, contactless switches KS7 and KS8 are fixed for detecting the positional base point of the plate 83 and the terminal point of displacement. Referring now to Figure 18, a block diagram illustrating the signal transmission route for controlling the automatic winding and doffing mechanism is illustrated. Referring to the drawing, a console of the digital panel mechanism 7 comprises a 10-key pad into which preset values and motor speed control values for the knitting machine are input. The digital panel includes function keys, monitors and trouble shooting lamps. A central processing unit (hereinafter referred to as "CPU") (not shown) performs processing in accordance with the pre-input sequence control program. The CPU is positioned in the digital panel 7 . The digital panel is connected to the ACI motor control panel 9 and the auto doffer control panel 10 . ACI control panel 9 and auto doffer control panel 10 are connected to each other. The ACI motor control panel 9 is connected to the motor M of the knitting machine for controlling the machine. The auto doffer control panel 10 has the following components connected thereto: 1) contactless switches KS7 (base point) and KS8 (terminal point) for confirming positions of the gate opening and closing; 2) gate opening-closing motor M1 ; 3) contactless switches KS3 (base point) and KS4 (terminal point) for confirming a position of the fabric cutting device 48 ; 4) fabric cutter displacing motor M2 and cutter motor M3 ; 5) contactless switches KS13 (base point) and KS14 (terminal point) for confirming a position of the fabric doffing device; 6) motor M4 for displacing the fabric doffing device; 7) contactless switches KS11 (base point) and KS12 (terminal point) to confirm a locking-unlocking position for locking and unlocking the winding roll; 8) motor 5 for locking and unlocking the winding roll; and 9) contactless switch KS2 for confirming stop of the winding unit at a fixed position. These mechanisms and components transmit signals detected thereby to the auto doffer control panel. When the mechanisms connected to the auto doffer control panel 10 are operational, corresponding signals indicating that the doffer is in operation are transmitted to the digital panel device 7 . When operational trouble occurs in the mechanisms connected to the auto doffer control panel 10 and in the yarn feeding system, signals enabling the doffer to halt (wait) operation are transmitted from the digital panel device 7 to mechanisms connected to the auto doffer control panel 10 . The ACI motor control panel 9 transmits to the auto doffer control panel 10 signals obtained from mechanisms connected to the auto doffer control panel 10 , indicating that the knitting machine is rotating. Signals from the contactless switch KS1 , indicating the speed and number-of-revolutions of the knitting machine, are transmitted to the CPU of the digital panel device 7 . The output side of the CPU is connected to the motor M of the knitting machine through the ACT motor control panel 9 . Signals from the contactless switch KS1 control the speed of the motor M of the knitting machine, for example, three steps as normal, medium, and low modes with the ROM incorporated into the ACI motor control panel 9 and programmed beforehand. The contactless switch KS1 is connected to the auto doffer control panel 1O through the digital panel device 7 . When the number of detected revolutions of the knitting machine reaches a preset value, stop signals are transmitted to the ACI motor control panel 9 through the digital panel device 7 . The stop signals transmitted to the ACI motor control panel 9 are transmitted as retardation signals to the motor M connected to the output side of the ACI motor control panel 9 to stop the knitting machine at a fixed position after driving at low speed. When the knitting machine is stopped, the contactless switch KS2 detects the fixed stop position of the winding unit. Fixed position stop signals are transmitted to the auto doffer control panel 10 . The fixed position stop signals of the winding unit 4 transmitted to the auto doffer control panel 10 are in turn transmitted to a mechanism connected to the output side of the panel 10 and then further transmitted to the mechanism after completion of an operation of one mechanism performed in the order of desired operations. A microswitch KS17 , for confirming that the fabric is wound on the winding roll 21 , is connected to the digital panel 7 . The switch KS17 operates when winding of the fabric on the winding roll 21 fails. At that time stop signals are transmitted to the digital panel 7 to stop the motor M connected through the ACI motor control panel 9 , as well as the other mechanisms connected to the auto doffer control panel 10 . An operation panel 84 enables full automatic operation and allows a series of mechanisms to automatically operate, and operate in semi-automatic operation, as well as to allow each mechanism to operate independently from the others when wrong operation is caused, and manual operation is fixed to the auto doffer control panel 10 . A detailed description of operations of the automatic fabric winding mechanism of this invention on the circular knitting machine will now be made with reference to a flow chart shown in Figure 19. The reference numbers N100 to N200 represent steps in the flow chart. When the knitting machine is started, a preset counter of the digital panel 7 begins counting, and the contactless switch KS1 inputs the signals indicative of the number of revolutions of the knitting machine into the central processing unit ("CPU" hereafter) (not shown) of the digital panel 7 . An accumulated value of the number of revolutions is calculated for comparison with a sequence process algorithm inputted beforehand. (N step 100 ). In the N step 101 , the number of revolutions of the knitting machine is compared with a preset value to determine if the number of revolutions has reached that value. When the number of revolutions reaches the preset value, the motor is retarded according to an instruction of the motor control panel, placing the knitting machine in the low speed driving mode (N step 102 ). When the number of revolutions is under the preset value, the knitting machine continues operating. In the N step 103 , the winding unit has reached the fixed stop position. Contactless switch KS2 determines the fixed stop position. In the N step 104 , if the winding unit reaches the fixed position, the knitting machine is stopped. If the winding unit has not reached the fixed position, the machine is driven at low speed until the unit reaches the fixed position. In the N step 105 , the switch KS18 compares the diameter of the fabric package with a standard value of 200 mm. If the diameter of the fabric package is more than 200 mm, the operation is shifted to the N step 106 in which the contactless switch kS2 determines the fabric package is in the fixed position. When the diameter is less than 200 mm, the operation is checked with the semi-auto mode. If the winding unit in not in the fixed position error is implied, and the operator performs checking. In the N step 107 , when the winding unit is stopped in the fixed position, the geared motor 5 of the lever locking and unlocking mechanism 37 is driven. Thus, the cam 38 fitted onto the shaft of the geared motor 5 turns by 90° in the vertical direction and abuts on the turning lever 28 for turning the lever and releasing the free end of the winding roll 21 . In the N step 108 , the contactless switch KS12 determines the position in which the turning lever 28 turns for locking and unlocking the winding roll 21 . When the turning lever 28 has been turned to the fixed position, the operation is shifted to the N step 109 and the geared motor M5 is stopped. Driving of the geared motor M5 continues if the turning lever 28 has not turned to the fixed position. After the geared motor M5 has stopped, operations in the N steps 110 through 113 for opening the gate 12 , and the N steps 114 through 117 for driving the cutter motor 62 of the fabric cutting device 48 and the cutter displacing motor 52 proceed simultaneously. In the N step 110 , determinations are made as to whether the contactless switch KS2 for stopping the winding unit 4 at the fixed position is operative and the switch KS12 for locking-unlocking the winding roll 21 is operative. When the contactless switch K2 for stopping the winding unit 4 at the fixed position, and, the KS12 switch for locking-unlocking the winding roll 12 are operative, the motor M1 for opening and closing the gate 12 is driven for opening the window of the gate 12 . (N step 111 ) A contrary result implies error and the operator performs checking. In the N step 112 , the contactless switch KS8 determines whether the gate has been opened. If the gate has been opened, the operation is shifted to the N step 113 in which the gate opening-closing motor M1 is stopped. If the gate has not been opened, the gate opening-closing motor M1 continues rotating until the gate is opened. In the N step 114 , the determinations are made whether the contactless switch KS2 for stopping the winding unit 4 at the fixed position is operable, and whether the KS12 for locking-unlocking the winding roll 21 is operable. When the contactless switches KS2 (fixed position stopping of the winding unit 4 ) and the KS12 (for locking-unlocking of the winding roll 21 ) are determined operable, the cutter motor M3 and cutter displacing motor M2 are enabled. If the switched are not operable, error is implied and the operator checks for error. In the N step 116 , a determination as to whether the fabric cutting mechanism 48 has reached the terminal point is made. In the N step 117 , if the fabric cutting mechanism 48 has reached the terminus, the cutter displacing motor M2 stops; otherwise, the cutter displacing motor M2 continues operation. In the N step 118 the cutter displacing motor M2 rotates in the reverse direction to return the cutter to the initial base position (N step 119 ) if the contactless switch KS2 for the fixed position stop of the winding unit 4 , and the KS12 for locking unlocking of the winding roll 21 are determined to be in operation; otherwise, error is implied and the operator performs checking. In the N step 120 , if the cutter has returned to its initial base position, the cutter displacing motor M2 is stopped (N step 121 ); otherwise, the cutter displacing motor M2 continues operation. In the N step 119 , when the contactless switch KS2 for the fixed position stop of the winding unit 4 and the KS12 for opening and closing the gate 12 are in operation, the step is shifted to the N step 123 in which the motor for doffing the fabric is driven to push the fabric on the winding roll 21 outside of the machine so that the fabric may be doffed. In the N step 124 , if the fabric doffing position 47 is at the terminal position, the fabric doffing motor M4 is stopped (N step 125 ); otherwise, the fabric doffing motor M4 is stopped. In the N step 126 , if the winding unit is in the fixed, stop position, and the gate 12 is opened for the fixed position stop of the winding unit 4 , the fabric doffing motor is rotated in the reverse direction and the fabric doffing mechanism 47 returns to the initial base position (N step 127 ); otherwise, error is implied and the operator performs checking. In the N step 128 , if the fabric doffing mechanism 47 has returned to the initial base position as determined by the switch KS13 , the motor for the fabric doffing device 47 is stopped (N step 129 ); otherwise, driving of the motor for the fabric doffing device 47 continues. In the N step 130 , the switch KS 13 determines whether the motor M4 for fabric doffing has terminated. If that motor is off, the motor M1 for opening and closing the gate 12 is rotated in the reverse direction so that the gate 12 is displaced to the initial closure position; otherwise, error is implied and the operator performs checking. In the N step 132 , if the gate has been closed, the motor M1 for opening and closing the gate 12 is stopped. In the N step 134 , if the doffing device 47 and cutter are in fixed stop positions as determined by the switch KS13 (confirming the base point of the mechanism 47 ) and KS3 (confirming the base point of the cutter), the motor M5 for actuating a locking-unlocking cam 38 for the winding roll 21 is rotated in the reverse direction and the winding roll 21 is turned and locked by the turning lever 28 (N step 135 ); otherwise, error is implied and the operator performs checking. In the N step 136 , the fabric retention confirming switch KS11 determines whether the turning lever 28 for locking-unlocking of the winding roll locks the winding roll. In the N step 137, if the turning lever 28 is retaining the winding roll, other mechanisms and components are sensed to determine whether they are stopped: the driving part for displacing the cutter; the closure of the gate 12 ; the locking of the winding roll by the locking-unlocking cam 38 ; and whether the fabric doffing device is stopped or performed in base positions. If the above mechanisms are stopped, the knitting machine is started again; otherwise, error is implied, and the operator performs checking. The invention provides the benefits and advantage of relieving the knitting machine operator of heavy labor normally associated with conveyance of the knitted fabric roll, and enables an increase in knitting machine operation. The foregoing embodiments are to be considered illustrative, rather than restrictive of the invention and those modifications which come within the meaning and range of equivalents of the claims are to be included therein.

Claims: Apparatus for automatic winding and doffing of knitted cloth on a circular knitting machine having a winding unit (4) disposed below the cylinder and revolving synchronously with the cylinder, and which drives fabric delivery rolls (19, 20) through a power transmission mechanism interconnected to the rotating winding unit (4) having a fabric winding roll (21) for winding knitted cloth, said winding roll (21) having two opposed ends; means for guiding (43) fabric to the winding roll (21) at the start of fabric winding; means for stopping the fabric winding roll (21) after a predetermined amount of fabric has been wound on the winding roll (21); means for cutting (48) the fabric after fabric winding; fabric doffing means (47) for doffing the fabric from the winding roll (21) in the direction of the roll axis after a fixed length of fabric has been wound on the fabric roll; and a frame having opposed winding apparatus frame arms (16, 17); being characterized in that said winding roll (21) includes means for changing the diameter of the roll (21) to allow a fabric wound thereto to be doffed therefrom, comb means (35) positioned on the surface of the roll (21) and movable from a retracted position below the surface to an extended position projecting from the surface of the roll (21) for engaging the cloth and retaining the cloth onto the winding roll (21) and means pivotally connecting one end of the winding roll (21) to one of the frame arms (16, 17). Apparatus according to claim 1 wherein the winding roll (21) includes two channel members (21a, 21b) dividing the surface of the winding roll (21) into two half-sections, and including means for moving the half-sections relative to each other for changing the cross sectional size of the winding roll (21). Apparatus according to one of the claims 1 or 2, wherein the channel members (21a, 21b) of the winding roll (21) include guide channel members (21e, 21f) having holes (21g, 21h, 21j, 21k), and wherein the half-section channel members (21a, 21b) engage the guide channel members (21e, 21f) and are guided along the holes (21g, 21h, 21j, 21k) when the cross-sectional size of the winding roll (21) is changed. Apparatus according to one of the claims 1 to 3 wherein a pivotally mounted turning lever (28) is supporting the other end of the winding roll (21) so that the other end of the winding roll (21) may be moved from a home, winding position to an unloading, doffing position and said doffing means (47) including a doffing plate (49) for pressing the side of a wound fabric roll from the winding roll (21). Apparatus according to one of the claims 1 to 4, and further including locking means (37) operatively connected to the turning lever (28) for locking the turning lever (28) in a position in which the turning lever (28) supports the winding roll (21) in the home, winding position and for unlocking the turning lever ((28) to allow the turning lever (28) to pivot and disengage from the winding roller (21), said locking means (37) including motor means (39) operatively connected to the cam (38) for rotating the cam (38) for turning the lever arm (28). Apparatus according to one of the claims 1 to 5 including a gate (12) positioned adjacent the winding unit (4) between the frame arms (16, 17) for protecting and substantially covering the winding unit (4), and including means for automatically opening and closing the gate (12) when doffing the knitted fabric from the winding roll (21). Apparatus according to one of the claims 1 to 6 wherein one of the frame arms (16, 17) is substantially C-shaped and bent in the direction along which the fabric is doffed. Apparatus according to one of the claims 1 to 7 wherein the fabric cutting means (48) is positioned apart from the winding unit (4). A method of automatically winding and doffing knitted fabric on a circular knitting machine including the steps of guiding the knitted fabric to a winding roll (21) positioned between opposed winding apparatus frame arms (16, 17), catching the fabric on the winding roll (21) by engaging the guided fabric onto a plurality of combs (35) that are positioned on the winding roll (21) and that extend beyond the peripheral surface of the winding roll (21), winding the fabric onto the winding roll (21), detecting the length of fabric wound onto the winding roll (21), retracting the combs (35) into the winding roll (21), doffing the fabric from the winding roll (21), and opening a gate (12) which covers and protects the winding roll (21) to allow the knitted fabric to be doffed outside the machine.

Inventors: SWAZAKI MASATOSHI, TSUCHIYA KOJI, SWAZAKI, MASATOSHI, TSUCHIYA, KOJI
Applicants: PRECISION FUKUHARA WORKS LTD, PRECISION FUKUHARA WORKS, LTD
Application year: 1991
Main classification: D04B15
IPC codes: D04B35, D04B15