JPS633981B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wefting device for a fluid injection type loom, and particularly to a wefting device for controlling the flow rate of wefting fluid during transient operating conditions to be equal to the flow rate during steady state. Related to equipment.

The injection timing of horizontal injection nozzles is generally controlled by a mechanical cam. The rotation of this cam is driven by the main shaft of the loom in order to synchronize it with the movement of the loom.

By the way, during transient operation of the loom, such as when starting up, the rotational speed of the loom does not reach the steady rotational speed. As a result, the injection period at startup becomes longer than the injection period during steady operation, and in extreme cases, weft yarn breakage accidents occur and instability in weft insertion is unavoidable.

Therefore, the invention of Japanese Patent Publication No. 57-38699 ``Jet Loom'' is designed to control the flow rate of wefting fluid in relation to the rotational speed of the loom. However, in that invention, the weft thread flying state when the loom is started is different from that during steady rotation, so the instability of weft insertion still remains unsolved.

The purpose of the present invention is to stabilize the weft insertion by controlling the transient rotational state of the loom, mainly the injection time of fluid at startup, that is, the flow rate, so that it is the same as the flow rate during steady rotation. .

Based on the above object, the present invention detects the start timing of fluid injection from the rotation angle of the loom during transient rotational operation such as when starting the loom, and after a preset delay time from that point, the fluid is By starting the injection of the fluid, the fluid injection time, that is, the fluid flow rate, is kept constant under transient rotational speed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be specifically described below based on an embodiment shown in the drawings.

First, FIG. 1 shows a weft inserting device 1 for a fluid jet loom according to the present invention. The weft yarn 2 is fed by a yarn supplying body 3
From there, it is fed out by the length measuring device 4 to the length required for weft insertion, stored in a storage device 5, and then guided to a nozzle 8 for weft insertion via clampers 6 and 7. The clamper 6 is operated by a cam 9 that is synchronized with the rotation of the loom. On the other hand, a fluid 10 such as air or water reaches the nozzle 8 through a supply path 15 through, for example, a mechanical injection control valve 11 and an electromagnetic type control valve 12 that closes when energized. The injection control valve 11 is operated by a cam 13,
This cam 13 rotates in synchronization with the movement of the loom,
From injection start timing _tS to end timing _tE , the cam follower 14 is operated to open the injection control valve 11. Therefore, when the fluid 10 can pass through the injection control valve 11 and the control valve 12, it reaches the nozzle 8 via the supply path 15. Further, the control valve 12 is controlled by a control device 16. When the loom is in a transient state, this control device 16 uses the transient rotational speed of the loom as input information, and calculates a necessary delay time ΔT from the fluid injection start timing _tS.
is selected, and the control valve 12 is opened during the period between the delay timing t _D corresponding to this delay time ΔT and the normal end timing t _E , and when the loom is in a steady rotation state, the control valve 12 is opened. is always open, and functions to control the fluid 10 only by the injection control valve 11.

Next, FIG. 2 shows a circuit array of the control device 16. This control device 16 has a cam 1 as a main part.
encoder 17 interlocked with the rotation of No. 3; detectors 18 and 19 for rotation angles θ _S and θ _E corresponding to start timing t _S and end timing t _E ; identification circuit 20; delay time setting circuits 21 and 22; and switching circuit 23.
and a priority circuit 24 as main parts. The above detectors 18 and 19 are connected to one input terminal of AND gates 25 and 26, respectively, and the output terminals of these AND gates 25 and 26 are respectively connected to a counter 2 as an identification circuit 20.
0a and the reset input of flip-flop 20a as priority circuit 24, respectively. The set input of flip-flop 24a is connected to detector 18. Also, "1" and "2" on the counter 20a
The output terminals of are connected to one input terminal of an exclusive-or gate 28 of the switching circuit 23 via delay time setting circuits 21 and 22 such as monostable multivibrators and an OR gate 27, respectively. Further, the output terminal of "2" of the counter 20a is connected to the AND gate 25 through the NOT circuit 29.
26 other input terminals, respectively. The output terminal of the flip-flop 24a is connected to the other input terminal of the exclusive-or gate 28 of the switching circuit 23. On the other hand, the input terminal 30 of the stop signal A is connected to the clear terminals of the counter 20a and the flip-flop 24a, and to one input terminal of the NOR gate 31 of the switching circuit 23. The other input terminal of this NOR gate 31 is
It is connected to the output end of 8, and the output end is
It is connected to the control terminal or base of a switching element, such as a transistor 32. The transistor 32 is connected in series with the control valve 12 and the excitation coils 33 and 34 of the clamper 7 between a power supply terminal 35 and a ground 36.

Next, referring to FIG. 3, the above-mentioned wefting device 1
Explain the operation. Figure 3 shows the number of revolutions N of the loom versus the time t from the start of the loom to the steady state of operation;
Open/close states of injection control valve 11 and control valve 12, stop signal A, angle signals θ _S , θ _E , delay time signal M ₁ ,
M ₂ , output signals Q, B ₁ , B ₂ and the injection status of the fluid 10 are shown, respectively. Loom rotation speed N
As already mentioned, reaches the steady rotational speed N ₀ after a transition time τ from the start-up time t ₀ . FIG. 3 is drawn on the assumption that the weaving is performed twice during this transition time τ. When the rotational speed N is low, the rotational speed of the cam 13 is also low, so the injection control valve 11 maintains an injection period longer than the steady-state injection period T in inverse proportion to the transient low rotational speed N.
It becomes a released state at T ₁ and T ₂ . In other words, the injection period T in a steady state is constant from the injection start timing _tS to the injection end timing _tE , but the transient time τ
The injection periods T ₁ and T ₂ are transient functions of the rotational speed N and are indefinite. These injection periods T ₁ and T ₂ are
It is expressed as follows using delay times ΔT ₁ and ΔT ₂ .

T ₁ = T + ΔT ₁ T ₂ = T + ΔT ₂ Now, when the loom is stopped, “H” is applied to the input terminal 30.
level stop signal A is present, which causes counter 20a and flip-flop 24
a has been returned to its initial state. When the loom starts
When starting at _t0 , the stop signal A changes from the "H" level to the "L" level. At this time, the Nandogade 31 receives input signals of "L" level on both sides, so it outputs an output signal _B2 of "H" level.
The transistor 32 is turned on, and the excitation coils 33 and 34 of the clamper 7 and the control valve 12 are brought into an excitation state. As a result, the clamper 7 and the control valve 12
is closed. When the rotation angle θ signal of the encoder 17 reaches the rotation angle θ _S , the detector 18 applies an “H” level angle signal θ _S corresponding to the start timing t _S to the set input terminal of the flip-flop 24a. and change the output signal Q to "H" level,
At the same time, it is sent to one input terminal of the AND gate 25. Since the AND gate 25 receives the "H" level signal on the other side, it sends the "H" level angle signal θ _S to the clock input terminal of the counter 20a. Here, the counter 20a counts "1" corresponding to the first weft insertion, operates the delay time setting circuit 21 with its output, generates the "H" level delay time signal _M1 , and outputs the OR gate. 27 to the exclusive use save or gate 28 of the switching circuit 23. The pulse width of this delay time signal _M1 corresponds to the delay time _ΔT1 . Excreuse Eve or Gate 28
When receiving "H" level signals at both input terminals, the NOR gate 31 generates an "L" level output signal _B1 , so the NOR gate 31 continues to generate "H" level signals. For this reason, the control valve 12
It remains closed. However, after the delay time ΔT ₁ has elapsed, the delay time signal M ₁ changes from the “H” level to the “L” level, so the output signal B ₁ of the exclude-or-gate 28 becomes
Since the output signal _B2 of the NOR gate 31 changes from the "L" level to the "H" level, and conversely from the "H" level to the "L" level, the switching transistor 32 becomes cut off. At that point, the control valve 12 changes to the open state. Subsequently, when the first end timing _tE arrives, the detector 19 generates an angle signal _θE of "H" level,
AND gate 26 to flip-flop 24a
Its output signal Q
changes from "H" level to "L" level.
For this reason, Excreuse Eve or Gate 2
The output signal B1 of the NOR gate ₃₁ changes from the "H" level to the "L" level, and the output signal _B2 of the NOR gate 31 changes from the "H" level to the "L" level.
Changes from "L" level to "H" level. Therefore, the switching transistor 32 becomes conductive, and the control valve 12 closes at that point. As already mentioned, the injection control valve 11
is already in the open state at the start timing _tS , but since the control valve 12 becomes open only after the delay time _ΔT1 , the injection of the fluid 10 is performed in the same manner as in the steady rotation state. This will be performed only during the regular injection period T.

When the angle signal θ _S is input corresponding to the second start timing t _S , the flip-flop 24
a is set again, and the counter 20a is
2, and the second delay time setting circuit 22
Activate. Therefore, the delay time setting circuit 22
A delay time signal M ₂ of "H" level with a pulse width corresponding to the delay time ΔT ₂ is generated and sent from the OR gate 27 to the exclude-or gate 28 . Here again, like the first time, the control valve 12 becomes open after the delay time _ΔT2 , so the fluid 10
The injection starts substantially at the time of the delay time and continues over the regular injection period T.

If two injections are performed during this transient time τ,
Since the loom enters a steady rotation state, no further control is required. Therefore, the output of "2" from the counter 20a is input as an "L" level signal to the AND gates 25 and 26 via the NOT circuit 29, and the subsequent input of the angle signals θ _S and θ _E is prohibited. Therefore, the output signal Q of the flip-flop 24a remains at the "H" level, and therefore the output signal _B1 of the exclusive-or-gate 28 remains at the "H" level, and the NOR gate 31
The output signal _B2 remains at the "L" level. This causes transistor 32 to be cut off and therefore control valve 12 to remain open thereafter. In this way, under steady operating conditions,
The injection of the fluid 10 is controlled only by opening and closing the injection control valve 11.

Note that in the above embodiment, the maximum count value of the counter 24a is set to "2" on the assumption that there will be two weft operations during the transient time τ from startup to steady operation. Correspondingly, two delay time setting circuits 21 and 22 are provided, and these can be set to one or three depending on the number of horizontal insertions in the transient state.
More than one can be provided as needed. Also, the control device 1
Since the logic circuit No. 6 is just an example, the intended purpose can be achieved with combinations other than this logic.

In the present invention, even when the loom is in a transient rotation state lower than the steady rotation speed, the fluid injection period, that is, the fluid flow rate, is controlled to be the same as the steady flow rate, so weft breakage and unstable wefting can be avoided. In addition, the flight time of the weft yarn is constant regardless of the rotation speed of the loom, and the time when the weft yarn reaches the opposite nozzle side is also stabilized, making it possible to weave high-quality fabrics.
Furthermore, since the control valve and the control device do not substantially function during steady operation, they do not cause the weaving to become unstable during steady operation.

[Brief explanation of the drawing]

FIG. 1 is a diagram of a wefting device for a fluid jet loom according to the present invention, FIG. 2 is a block diagram of a control device, and FIG. 3 is a time chart during operation. 1... Wefting device for fluid jet loom, 2...
Weft, 6, 7... Clamper, 8... Nozzle, 1
0... Fluid, 11... Injection control valve, 12... Control valve, 15... Supply path, 16... Control device, 17...
...Encoder, 18, 19...Detection circuit, 20...
...Identification circuit, 20a...Counter, 21, 22...
...Delay time setting circuit, 23...Switching circuit, 24...Priority circuit, 24a...Flip-flop.

Claims (1)

[Scope of Claims] 1. A weft insertion nozzle that injects fluid to make the weft fly, and an injection control valve that is located in the fluid supply path and controls the injection of fluid in synchronization with the rotation of the loom. , a control valve that is interposed in the supply path and controls the fluid flow rate, and a control valve that detects the start timing of fluid injection during the transient operating state of the loom, and after a preset delay time from the start timing, the control valve A weft inserting device for a fluid jet loom, comprising: a control device for opening the wefting device. 2. A start timing detector, an identification circuit that determines the number of weft insertions during a transient state of the rotational speed of the loom, and a signal with a predetermined delay time generated according to the judgment of this identification circuit. A control device comprising: a delay time setting circuit to open the control valve after the delay time; a switching circuit to open the control valve after the delay time; and a priority circuit to send a signal to the switching circuit to keep the control valve open after the transient operation period has elapsed. A weft inserting device for a fluid jet loom according to claim 1, characterized in that the weft inserting device comprises: