JPS6117971Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a warp tension adjusting device used when supplying warp yarns to a circular knitting machine that uses warp yarns.

In a circular knitting machine, as the warp is fed, the warp of the warp wound around the beam gradually decreases, and as the warp decreases, the tension of the warp changes. Furthermore, when the machine stops due to thread breakage, etc., the tension of the supplied warp threads decreases, causing them to become loose. In such cases, the warp tension has conventionally been controlled by applying a brake band to the cylinder of the warp beam and adjusting the braking force as shown in FIGS. 1, 2 and 3.

That is, the warp threads 1 are sent from the beam 2 around the dancer rollers 3 to the main body of the machine. A first brake band 5 and a second brake band 6 are applied to the cylinder 4 of the beam 2. When the tension of the warp threads 1 increases, the dancer roller 3 rises, operating the upper limit switch 7 and causing the first solenoid 8 to operate. This action turns the brake band adjusting nut 9, adjusting the braking force of the first brake band 5 and reducing the warp tension. Further, when the tension of the warp threads 1 decreases, the dancer roller 3 descends, operating the lower limit switch 10 and causing the second solenoid 11 to operate. This action increases the braking force of the second brake band 6 and stops the warp from being sent out. However, with such conventional brakes, it is difficult to minutely adjust the braking force in response to minute changes in tension.
It was not possible to make stepless adjustments, and the adjustment was made in stages, making it impossible to avoid horizontal stripes on the knitted fabric.

In order to eliminate the above-mentioned drawbacks, this invention intervenes with a continuously variable transmission in the middle of the beam rotation drive mechanism, and by finely controlling this continuously variable transmission, the rotation of the beam is adjusted almost steplessly, and the warp threads are rotated. The tension is adjusted to prevent horizontal stripes from forming on the knitted fabric due to changes in tension.

Embodiments of the present invention will be described below based on the drawings. The electric motor 12 of the first drive unit drives the ring cone transmission 1 through the variable pitch pulley 13.
4 input shaft is rotated. A worm 18 is rotated from the output shaft of the ring cone transmission 14 via a manual clutch 15 and gears 16 and 17. A beam 2 around which the warp threads 1 are wound is fixed to a rotating shaft 20 of a worm wheel 19 that meshes with the worm wheel 18, and the warp threads 1 are sent out by rotation of the worm wheel 19. Warp 1 is beam 2
Two guide rollers 2 fixed in parallel position in front of
1 and a dancer roller 3 which is located in the middle and whose position can be changed up and down, and is supplied to the knitting section (not shown) of the circular knitting machine main body. The dancer roller 3 is rotatably attached to one end of a pair of levers 23 that are parallel to the beam 2 and can pivot about a fixed pivot shaft 22 as a fulcrum. A weight 24 is attached to this lever 23 to determine the tension of the warp threads. Near the other end beyond the fulcrum of the lever 23, there is an upper limit switch 7 for limiting the turning range of the lever 23;
A lower limit switch 10 is installed, and an upper limit sensor 25 and a lower limit sensor 26 are installed at a minute interval between these two limit switches. Further, a pilot motor 27 of a second drive device is provided for moving the shifter of the ring cone transmission 14, and this pilot motor 27 is connected to an upper limit sensor 25 and a lower limit sensor 26.
The pilot motor is actuated via the pilot motor control box 28 by the signal . A manual handle 29 is attached to the shaft end of the worm 18, and by disengaging the manual clutch 15, the beam 2 can be rotated manually.

Next, the effect will be explained. Suppose now that the tension in the warp threads 1 gradually increases, the dancer roller 3 pivots upward, and the lever 23 contacts the upper limit sensor 25.
From the upper limit sensor motor 25, as shown in Fig. 6,
An ON signal is output, and this signal is OR gate 3 in Figure 5.
0 and AND gate 31 for increasing the speed of the pilot motor
sent to. The OR gate 30 receives this signal and sends a signal to the flip-flop timer 32, and the flip-flop timer 32 turns on at fixed time intervals while receiving the signal from the OR gate 30.
send out a signal.

The AND gate 31 receives a continuous signal from the upper limit sensor 25 and an intermittent signal from the flip-flop timer 32, and outputs the signal to the pilot motor 2.
7 speed increase signal is sent. The pilot motor 27 is intermittently rotated by this signal, and the shifter of the ring cone transmission 14 is intermittently moved to the speed increasing side, thereby causing the beam 2 to rotate intermittently at an increased speed. By increasing the speed of beam 2, the warp tension returns to the predetermined level,
When the dancer roller 3 turns downward, the lever 23 and the upper limit sensor 25 are no longer in contact with each other, and the signal from the upper limit sensor 25 is cut off. Therefore, the rotation of the pilot motor 27 is stopped and the shifter of the ring cone transmission 14 is also not moved and stops at that position.
When the warp tension decreases and the dancer roller 3 turns downward, a similar action causes the AND gate 3 to rotate downward.
3 sends out a deceleration signal for the pilot motor 27, and the rotation of the beam 2 is decelerated in the opposite manner to the above. Note that the lever 23 may exceed the upper limit sensor 25 or the lower limit sensor 26 and switch the upper limit switch 7.
Alternatively, when the lower limit switch 10 is activated, the machine is immediately stopped.

As detailed above, according to the present invention, changes in the warp tension are detected by the movement of the dancer roller in a minute range, and the warp tension is adjusted by applying the change in the minute range as a gradual change to the rotation of the beam. As a result, there is no sudden change in tension and the tension is averaged out, making it possible to prevent horizontal stripes from forming on the knitted fabric. In addition, since the tension can be finely adjusted, it is possible to use elastic warp yarns, and a knitted fabric with a good texture can be knitted.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the first brake device of a conventional warp tension adjustment device, FIG. 2 is an illustration of a nut turning mechanism for tension adjustment, FIG. 3 is a schematic diagram of the second brake device, and FIG. 5 is a block diagram showing the operational relationship of the device of the present invention, and FIG. 6 is a diagram showing the temporal relationship of the operation of the device of the present invention. DESCRIPTION OF SYMBOLS 1... Warp, 2... Beam, 3... Dancer roller, 12... First drive device, 14... Ring cone transmission, 25... Upper limit sensor, 26... Lower limit sensor, 27... Pilot motor (Second drive device), 28...Pilot motor control box.

Claims (1)

[Claim for Utility Model Registration] A device that adjusts the tension of the warp threads by rotating the dancer rollers when supplying the warp threads wound around a beam to the knitting section of a circular knitting machine, detects minute positional displacements of the dancer rollers. a continuously variable transmission disposed in the middle of the beam rotation drive mechanism rotated by the first drive device; a second drive device that operates the rotation operation section of the continuously variable transmission; 1. A warp tension adjustment device for a circular knitting machine, comprising: a control means for commanding rotation of a second drive device for operating the operation section in response to a signal from the detection means.