JPH0141740B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a set-up device for a knitted fabric in a flat knitting machine.

<Prior Art> It is common practice to use a set-up device when starting knitting of a knitted fabric in a flat knitting machine and pulling down the knitted fabric from the knitting position. The knitted fabric knitted at the gap of the needle bed is pulled down to the lower part of the needle bed using a set-up comb having set-up needles, and when the knitted fabric is pulled down to an appropriate length, the knitted fabric is nipped from both sides with take-down rollers. The knitted fabric is pulled down by rotating the rollers. In the above case, unless the pulling down of the knitted fabric by the set-up comb and the pulling down of the knitted fabric by the take-down roller are performed with the same pulling tension, there is a risk that the knitted stitches will become uneven.

〓Problems to be Solved by the Invention〓 After the knitted fabric is pulled down by set-up needles and hung down to an appropriate length below the needle bed, the knitted fabric is pulled down from both sides of the knitted fabric by a unwinding device made of rollers or an endless body. After nipping the knitted fabric, remove the set-up needle, and then
When the roller or endless body is rotated to pull down the knitted fabric, in the present invention, two types of functions are used: when the roller or the endless body is rotated and the knitted fabric is pulled down by the set-up needle, and when the knitted fabric is pulled down by the unwinding device. The purpose of this method is to prevent a difference in the pulling tension from affecting the stitches, and to always pull down the knitted fabric with a constant tension.

〓Means for solving the problem〓 A beam consisting of a plurality of set-up needles is installed in such a way that it can be approached and moved from below to the needle bed opening by means of an elevating member, and when knitting, the beam is In a set-up device that pulls down a knitted fabric by lowering the knitted fabric, the beam is supported by a beam lifting/lowering member via a support member that also serves as a tension sensor, and the tension sensor has a knitted fabric detected when the knitted fabric is pulled down. A circuit is provided to control the rotation of the elevating member drive motor based on a signal depending on the strength of the tension, and the rotation of the motor is controlled so that the set-up tension is maintained at a predetermined tension during set-up.

〓Operation〓 When lowering the beam material with set-up needles planted in parallel, the tension sensor that supports the beam material detects the downward tension, and if the detected value is smaller than the predetermined tension, Increase the rotation of the motor that lowers the beam support member, and when the tension is greater than a predetermined tension, reduce or stop the rotation of the motor to lower the knitted fabric under a constant tension. The stitches of the knitted fabric are kept uniform.

〓Example〓 An example in which the present invention device is implemented in a flat knitting machine having a pair of needle beds facing each other in a chevron-shaped manner will be described below.

Reference numerals 1 and 1 designate a needle bed supported by a frame 3 facing each other in a chevron shape, and a set-up device 5, a lowering device 6, and a removing device 7 are provided at the lower part of the needle bed gap portion 4 at the top.

The set-up device 5 is constructed as follows.

Set-up rails 8, 8 are rotatably supported on both sides of the machine by support arms 2, 2, . The set-up rail 8 has a screw thread formed on its surface, and as the set-up rail 8 rotates, a sensor support 9 is screwed onto the rail 8.
can be moved up and down along the set-up rail 8. A tension sensor 10 is supported on the sensor support 9 . tension sensor 10
consists of an opening-shaped frame 11 and a strain gauge 12 provided on the frame 11, and is screwed to the inverted T-shaped corner of the sensor support 9, and has a connecting plate screwed to the tip. 13 supports a beam 15 on which set-up needles 14 are arranged. A pin 17 is provided on a protrusion 16 provided on the sensor support 9, and is fitted into a long hole 19 of a hanging arm 18 that hangs down from the beam 15 in parallel with the connecting plate 13. Strain gauges 12 are installed at four corners of the inner edge of the frame 11 in the shape of an opening, so that when the frame 11 is strained, the strain is detected as an electrical quantity.

As shown in FIG. 9, the strain gauges 12 are connected to form a bridge circuit. Then, when a stable DC voltage is applied, R1=R2=R3=
If R4, the voltage between +OUT and -OUT is zero volts, and if any of the gauges of 1 or more synergistically changes its resistance value due to external force, the balance of the bridge will be lost and the voltage between +OUT and -OUT will change. Voltage is generated. When the amount of change is small with respect to the gauge resistance value, a proportional relationship is established between the generated unbalanced voltage and the applied external force.

Therefore, the degree of distortion is determined by detecting the unbalanced voltage that has occurred, and as will be described later, the knitted fabric is pulled down a certain amount at a time so that the distortion is within a predetermined range.

A bevel gear 20 is provided at the lower end of the set-up rail 8,
It meshes with a bevel gear 22 provided on the set-up shaft 21. A pulley 23 is provided at the end of the set-up shaft 21, and a belt 26 is spanned between it and a pulley 25 of a servo motor 24. Servo motor 24
is rotated by a signal from the tension sensor 10.

The lowering device 6 is constructed as follows.

Reference numeral 31 denotes a lowering roller supported by a roller shaft 32, and a roller 33 provided parallel to the lowering roller 31.
A belt 34 is placed between the two. A movable roller shaft 36 is provided opposite the roller shaft 32 and supported by a support block 35. The support blocks 35 are supported by sliding shafts 37, 37 on both sides of the knitting machine stand so as to be located outside the needle beds 1, 1. The sliding shafts 37, 37 are each slidably supported by a sliding bearing 38 provided on the frame 3. The support block 35 is connected to the crank arm 40 via a link 39.
0 is connected to a crank arm 42 via a connecting rod 41. A cam follower 43 provided at the tip of one arm of the crank arm 42 is biased by a spring 44 and is in contact with a moving side belt moving cam 45 .

The moving roller shaft 36 has a moving side lowering roller 54.
is supported by a roller 4 supported by appropriate means.
A moving side belt 47 is spanned between the moving side belt 6 and the moving side belt 47.

A joint 48 is provided at the end of the moving roller shaft 36.
is provided, and the moving side roller shaft 36 and shaft 49 are connected via a joint 48. The rotation of a motor 50 is transmitted to the shaft 49 via a power transmission means 51. Rotation is transmitted between the shaft 49 and the shaft 32 by gears 52 and 53.

The eye removal device 7 is constructed as follows.

Reference numeral 60 denotes a blind plate, which is installed in a beam 61 having a width equal to or an integral multiple of the needle pitch and larger than the needle bed width, and a wire 62 is provided at the tip thereof passing through the entire blind plate. beam 61
Both ends of the swing arm 63 are supported by a swing arm 63, and the swing arm 63 is urged clockwise in the drawing by a spring 64, and a cam follower 65 provided on the swing arm 63
is in contact with the eye removal cam 66. The blinding cam 66 is fixed to a cam shaft 67 together with the driven side belt moving cam 45.

Next, the operation of the device of the present invention will be explained.

To start knitting, the set-up needles 14 must be raised to the gap 4 between the needle beds 1, 1, as shown in FIG. For this purpose, by rotating the camshaft 67 and bringing the small diameter portion of the moving side belt moving cam 45 into contact with the cam follower 43, via the crank arm 42, connecting rod 41, crank arm 40, and connecting rod 39, The support block 35 is moved to the left in FIG. 3 by the tightening force of the spring 44 to open the gap between the belts 34 and 47.
Next, the set-up shaft 2 is moved by the servo motor 24.
1, the set-up rail 8 is rotated via the bevel gears 22, 20, and the sensor support 9, which is threadedly engaged with the set-up rail 8, is raised. When the beam 15 supported via the frame 11 and the connecting plate 13 also rises due to the rise of the sensor support, the rise occurs when the positioning switch detection plate 9a of the sensor support 9 comes into contact with the upper limit switch SU. Stop and set up needle 1
4 is located within the mouth part 4 (the third
figure).

Set-up is started from this state, and the knitted fabric F is pulled down by rotating the servo motor 24 in the opposite direction to when the set-up needles 14 are raised. At this time of pulling down, the sensor support 9 first descends due to the rotation of the set-up rail 8, and the frame 11 of the tension sensor 10 tries to descend along with it, but the set-up needle 14 holds the knitted fabric. Since the knitting speed is stopped, the knitting speed cannot be lowered below the knitting speed. Therefore, when the sensor support 9 descends faster than the knitting speed, the frame 11 is strained, and the strain gauges 12 provided at four locations on the frame 11 detect the strain. The strain gauges 12 constitute a circuit as shown in FIG. 9, each strain gauge 12 outputs a signal according to the degree of strain detected, and based on the signal, the rotation of the servo motor 24 is controlled.
The servo motor 24 is rotated while always applying a predetermined constant tension to the knitted fabric.

In this embodiment, tension sensors 10 are provided at both ends of the beam 15 so that the same numerical value can be obtained no matter where tension is applied to the set-up needle. The electrical operating state in this example will be explained with reference to FIG.

The knitted fabric lowering tension voltage detected by the tension sensors 10, 10 is input to the tension detection amplifier 71. Tension detection amplifier 71 is amplifier 7
It consists of 2, 73, and 74. Tension sensor 1
Since the voltage generated at 0 is minute, this amplifier 7
Amplify by 2.73. In addition, in this system, a pair of tension sensors 10 and 10 are used so that the same voltage can be obtained no matter which part of the set-up needle is applied tension.
The beam 15 of the set-up needle 14 is supported by an amplifier 74, and the voltages generated from each tension sensor 10, 10 are added together by an amplifier 74. The example shown in FIG. 10 has a twin bed mechanism and can be used in three types: single bed operation (left or right) and twin bed operation. When twin beds are used, amplifier 7
The voltages from 2 and 73 are added at amplifier 75, and 1/
Average with a gain of 2. When single bed,
Cancel the unused signal and set the gain to 1.
Switch to .

The signal leaving amplifier 75 enters amplifier 77.
Meanwhile, in this system, the feedback loop includes mechanical parts such as gears, and there is a risk that the servo loop may oscillate due to mechanical vibrations.
The low pass filter 76 avoids the resonance point of the loop and prevents oscillation. The amplifier 77 outputs the tension target value (voltage signal) and the tension sensor 1.
A comparison is made with the feedback voltages from 0 and 10, and the difference voltage becomes the command voltage in the tension control mode. Tension feedback is applied so that the comparison value here is balanced with OV. Amplifier 7
At step 9, the speed feedback voltage from the F-V converter 78, which is added to OV, is added to the command voltage from the amplifier 77, and the amplifier 79 stabilizes the rotation of the motor 24 and stabilizes it when the motor 24 is stopped. The output of the amplifier 79 drives the servo motor 24, which drives the set-up shaft 21 of the set-up beam raising/lowering member via the driver part 80, in accordance with the voltage from the driver part 80. Further, an encoder coaxial with the motor 24 generates a feedback pulse proportional to the rotation, and this pulse enters the F-V converter 78 and is converted into a voltage proportional to the pulse frequency, and this feedback voltage is as described above. It enters the amplifier 79 and stabilizes the rotation of the motor 24.

Then, a positioning switch detection plate 9 is provided on the sensor support 9 which is lowered by the rotation of the motor 24.
When a detects the intermediate switch SM, the camshaft 67
, the moving side belt, the moving cam 45 and the eye removal cam 66 rotate, and the moving side belt 47 approaches the belt 34 in the opposite way to the above, and the lower part of the knitted fabric F is covered with both belts 47, 34. The rotation of the motor 50 is transferred to the shaft 49 by a power transmission means 51 such as a chain.
and transmits its rotation to shaft 3 via joint 48.
6, and via the gear 53 meshing with the gear 52 of the shaft 49, the shaft 32 integrated with the gear 53 is rotated, and the belts 47, 34 are rotated in the direction of pulling down the knitted fabric F, respectively. Then, as the eye removal cam 66 rotates, the swing arm 63 pivots counterclockwise as shown in the fourth figure, and the wire 62 provided at the tip of the eye removal plate 60 is latched to the set-up needle 14. Then, by rotation of the cam 66, the stitch removal plate 60 is advanced to the loop, and as shown in FIG. 5, the loop is removed from the set-up needle 14, and the stitch removal work is completed.

Thereafter, the set-up device is lowered by the rotation of the servo motor 24 until the positioning switch detection plate 9a reaches the lower limit switch SL.

〓Effects of the Invention〓 As detailed above, the device of the present invention allows a beam formed by a plurality of set-up needles to be moved toward and away from the needle bed opening from below by means of an elevating member. In a set-up device that lowers a knitted fabric by lowering a beam during knitting, the beam is supported by a beam lifting member via a support member that also serves as a tension sensor, and the tension sensor has a knitted fabric. A circuit is provided to control the rotation of the lifting member drive motor based on a signal indicating the strength of the tension of the knitted fabric detected at the time of pulling down, and the rotation of the motor is controlled so that the set-up tension maintains a predetermined tension during set-up. Therefore, when knitting the knitted fabric, the pulling tension of the knitted fabric by the set-up device can be kept constant, and after knitting a predetermined length of the knitted fabric in this state, the knitted fabric is rolled down by the unwinding device. Therefore, the knitted fabric can be pulled down under a constant tension without causing fluctuations in the knitted fabric pull-down tension at the start of knitting and thereafter, and the knitted fabric has uniform stitches. can do.

[Brief explanation of drawings]

FIG. 1 is a front view, FIG. 2 is a plan view, and FIGS. 3 to 6 are vertical side views of the apparatus of the present invention, showing the process of operation in order. Figure 7 is an enlarged front view of the tension sensor, Figure 8 is a perspective view of the tension sensor, Figure 9 is an electric circuit diagram of the tension sensor,
FIG. 10 is an electrical circuit diagram after driving. 1... Needle bed, 4... Teeth opening, 8...
Set-up rail, 9...Sensor support, 10...
Tension sensor, 24... Drive motor.

Claims (1)

[Scope of Claims] 1. A beam formed by planting a plurality of set-up needles in a row is provided so as to be able to approach and leave the gap of the needle bed from below by means of an elevating member, and the beam is lowered during knitting. In the set-up device that pulls down the knitted fabric, the beam is supported by a beam lifting/lowering member via a support member that also serves as a tension sensor, and the tension sensor receives information about the tension of the knitted fabric detected when the fabric is pulled down. A knitting machine for a flat knitting machine, characterized in that a circuit is provided for controlling the rotation of a lifting member drive motor based on signals depending on strength and weakness, and the rotation of the motor is controlled so that the set-up tension is maintained at a predetermined tension during set-up. Output device. 2. The set-up device for a flat knitting machine according to claim 1, wherein the elevating member is a set-up rail made of a screw shaft to which rotation of a servo motor is transmitted. 3. The set-up device for a flat knitting machine according to claim 1, wherein the beam is supported by lifting members at both ends thereof.