JPS6328947A - Apparatus for indicating warp yarn cutting position - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a dropper device for a loom, and more particularly to a device for quantitatively calculating the position of warp yarn breakage when yarn breaks.

BACKGROUND OF THE INVENTION Dropper devices have conventionally been used to detect warp yarn breakage during weaving. Each dropper pin of the Dronbar device is supported by the warp threads, but when the warp threads break, each dropper pin falls and comes into electrical contact between a pair of electrodes on the dropper bar, generating an electrical signal.

When the loom stops due to such a warp yarn breakage, it is necessary to repair the warp yarn breakage after confirming the location of the yarn breakage. However, when a large number of warp yarn groups are arranged in parallel, it is difficult to confirm the yarn breakage position, and a lot of time is spent on detecting the breakage position.

BACKGROUND OF THE INVENTION In the field of measurement technology, changes in resistance values are used to measure distance. Such an indirect distance measurement technique can also be applied to the field of detecting the warp breakage position I of a loom. However, in order to put it into practical use, in addition to the problem of the linearity of the resistance value, the problem of the contact force M tffi between the dropper bottle and the dropper bottle in a dropped state must be solved.

Originally, an oxide film is easily formed on the surface of a dropper bottle, and an insulating film is also likely to be formed on the surface due to the humidity peculiar to textile factories, fluff in the air, starch scum, etc. For this reason, even though the drumper pin is constructed as a good conductor, it no longer becomes a good conductor as time passes during use. The existence of such contact resistance is the real reason why the warp yarn breakage position cannot be detected by simply measuring the resistance value.

By the way, since the above-mentioned insulating film causes poor contact between the dromper pin and the dropper bar, there remains a problem not only from the viewpoint of resistance measurement but also as a mere warp breakage sensor.

Therefore, the applicant of the patent applied a high voltage to the electrical closed circuit including the dropper pin and the dropper bar, and short-circuited the part where the contact resistance occurred by dielectric breakdown, in the idea of Utility Model Application Publication No. 58-184586. , have already proposed reducing the influence of contact resistance. It has been experimentally confirmed that even with the proposed technique, a contact resistance of about 30 [kΩ] is generated between the dropper bin and the dropper bar.

On the other hand, JP-A No. 61-75848 states that the resistance value of the dropper bar is desirably 10° to 103 [Ω], but for example, for a loom with a width of 150 [Ω], the value is The contact resistance of 30 (kΩ) in this case is not a negligible value, and appears as a position error of 20% or more.

Furthermore, in Japanese Patent Publication No. 59-16018, since only a voltage of about 0.6 (V) is applied between the dropper pin and the dropper bar, malfunctions due to poor contact between them are unavoidable.

Therefore, in the detection process, if there is a contact failure,
Practical measurements are almost impossible.

Furthermore, although it is stated that there is no change in resistance characteristics due to excellent contact performance, it is difficult to imagine improvement in contact performance without taking any measures on the dropper bottle side.

OBJECTS OF THE INVENTION Accordingly, an object of the present invention is to provide a dropper bin and a dropper bin.
To accurately measure the position of a dropper pin in a dropped state from a resistance value without being affected by contact resistance between the dropper pin and the paper.

Solution to the Invention Therefore, the present invention connects detection circuits to both ends of the dropper bar, and establishes an electrical relational expression for each end of the dropper bar, with the position of the dropped dropper bin as the boundary. , the contact resistance between the dropper bin and the dropper bar is eliminated from these two relational expressions, and from the relational expression after the contact resistance has been eliminated, the dropping position of the dropper bin, that is, the warp yarn breakage position, is determined by an arithmetic expression. . Note that such calculations are performed by a dedicated calculation circuit or the like, but in addition to such calculations, other necessary storage functions can also be realized using the functions of a microcomputer.

Structure of the Invention FIGS. 1 and 2 show the structure of the invention in relation to a dropper device 1.
1 shows the configuration of a warp breakage position indicating device 2 of the present invention.

The dropper device 1 is composed of a plurality of dropper bins 3 and a common dropper bar 4, as in the conventional case. This dropper pin 3 is a rectangular conductive plate, and is provided with a hole 6 through which the warp threads 5 pass approximately in the center thereof, and a hole 7 is formed in the receiver that intersects with the dropper bar 4 at its upper portion. Each warp yarn 5 in the warp group is passed from one surface of the romper pin 3 to the other surface, and is held at a constant height by its tension.

Further, the dropper bar 4 includes a pair of electrodes 9a and 9b with a U-shaped insulator 8 interposed therebetween, and the receivers of the dropper pins 3 in the same row pass through the holes 7 in a non-contact manner. In this state, when the warp threads 5 at a certain position break, the dromper pin 3 at that position loses the supporting force of the warp threads 5 and falls, and the receiver contacts the pair of electrodes 9a and 9b at the hole 7, and electrically connected between the two.

The warp breakage position indicating device 2 of the present invention includes a detector 10, a calculator 11, a memory 12, and an output device 13. The detector 10 has one electrode 9a
are connected to points A and B at each end of the
It is also connected to point 0 or point D at each end of the other electrode 9b. Note that this 0 point and D point are both earth 1.
Connected to 4. This detector 10 is connected to an output device 13 via an arithmetic unit 11. Further, the storage device 12 is connected to the arithmetic unit 11 in order to store constants necessary for calculations.

Embodiment 1 (FIG. 3) Next, FIG. 3 shows that when the dropper bottle 3 falls, a contact resistance r is applied between the electric currents i9a and 9b of the dropper bar 4.
A short-circuited state is shown using an electrical equivalent circuit.

The detector 10 includes two amplifier circuits 15 and 16. These are connected to points A and B, respectively, on the input side, and a voltage E is applied to each part via a resistor R0.
is applied. Suppose that the dropping position of the dropper bin 3 is a point, and based on the distance between points A and B, the distance ratio from this point to point A is k, and the distance ratio from this point to point B is k. Assuming that the distance ratio is (1-k) and the resistances between points A and B and points B and Rz are R+ and Rz, respectively, using the currents 1+ and Iz in each circuit, the following can be calculated. The formula holds true.

E= (Re +R+) tt +r (It
+I z)E”” (R6+Rt) It +
r (1+ + I z)-'-(Re +R1)
It = (Ro + Rz) It Now, assuming that the total resistance of the dropper bar 4 is R, the following equation holds true.

R,=kR,R2= (1-k)R (Ro +kR)It = (RO+ (1k)R)
ItRI++RIz Then, assuming that the distance from point A is 11 and the length of the barber 4 is L, the following formula holds true for the distance l from the relationship of -L to j2=.

RI++Iz Here, the resistance R0 is a constant determined at the time of design, and the length and resistance R are constants specific to the dropper bar 4.

Therefore, the distance l is determined by the above constants (L, R, and R,) and the currents r, , I2 flowing through the points A and B, regardless of the contact resistance r. Of course, this current It,
1 g may be detected by converting it into a voltage, for example, by a known method. The above-mentioned length and resistance R are displayed on the dropper bar 4 in advance, for example, and are stored in the storage device 12 in advance by an input operation. Therefore, the computing unit 11 calculates the distance l of the dropping position of the dropper bin 3 based on the above formula.
is determined based on the information (L, R and RO) from the memory 12. And at this time, output! S13 displays the distance l at that position quantitatively as a length or as the number of threads from one of the warp thread groups.

Note that the resistor R can be set by short-circuiting point A to ground 14, for example.
The detection may be performed once when the power is turned on. When turning on the power, if there is a risk that resistance R may be detected incorrectly if warp thread breakage occurs, the operator can use a command switch, etc. to set the resistance R to be measured when warp thread breakage has not occurred. You may also do so.

Further, if the resistivity ρ per unit length of the drone perper 4 is R=ρ·L, then the distance 2 is expressed by the following formula.

Here, the resistivity ρ is a value specific to the material of the dropper bar 4, so if you memorize the resistance R0 and the resistivity ρ in advance, you can find the distance 2 just by initializing the length. It turns out.

Embodiment 2 (FIG. 4) Originally, the dropper device 1 detects the state of warp yarn breakage, and warp yarn breakage detection has priority, and position detection is incidental. However, the detection of warp thread breakage is
It is desirable to be able to detect the vertical cut without changing its sensitivity depending on the position of the cut.

Therefore, in this embodiment 2, warp yarn breakage is first detected using high resistance R0 and high voltage E□, which have a relationship of resistance R0>>resistance R, and then position detection is switched to low voltage E and high resistance R0 is separated and the process is performed using only low abrasive force r0. In this case, in the first stage, a high voltage E is applied. Since the insulating film is destroyed by this, a certain distance 2 is required even in the conventional method.

However, since the contact resistance r is not zero, the influence of the contact resistance r should be removed by calculation.

Now, when warp thread breakage is detected, the changeover switch S1 is connected to the high voltages E and l of the thread breakage detection circuit. At this time, the high voltage EH1 detection voltage ■A is the current 1. It can be expressed by the following formula using .

EM -(R6+R1+r) ・In■EH-R
O.I.

r=When warp thread breakage does not occur) r>
>Rcr, R+ vH”1E) 1r〈When Ro (when warp thread breakage occurs) Ro〉〉r%
In such a warp yarn breakage detection operation, the insulation film is destroyed by the presence of the high voltage E8, and even if there is a contact resistance r, the yarn is always cut in a stable state by the amplifier circuit 17. Cutting conditions can be detected.

Further, due to the presence of the high resistance R0, when warp thread breakage occurs, it is not affected by the resistance R1 and the contact resistance r, and the detected voltage (2) is kept at approximately O(V). That is, the warp yarn breakage detection sensitivity is not affected by the warp yarn breakage position.

After that, the yarn breakage position is detected. In this case, the changeover switch S1 is switched from the high voltage E8 side to the low voltage EL side of the position detection circuit. At the same time, the detection voltage (2) is also input to the amplifier circuit 15 on the arithmetic unit 11 side.

The principle of digit 1 detection is the same as in the first embodiment. However, in this embodiment, since only one amplifier circuit 15 is provided, between the amplifier circuit 15 and the point A and the point B
An interlocking type changeover switch S2 is provided between the point and the point. First, the amount of electricity on the side of point A is input to the amplifier circuit 15. After that, the switch S2 is switched, and the amplifier circuit 15
The amount of electricity on the B point side is input to . In this way, the currents at points A and B are converted into voltages and are input to the input side of the amplifier circuit 15 with a time difference.

After that, the calculator 11 performs the same calculation as in the first embodiment,
Find the distance l.

Embodiment 3 (FIG. 5) Next, this embodiment shows another means for detecting yarn breakage regardless of the position of the warp yarn breakage. In addition, in the above example,
Although one of the pair of electrodes 9a and 9b was made of a resistor and the other was made of a good conductor, in this embodiment, both are made of a resistor. As shown in FIG. 5, a common resistor R0 is connected to points A and B by a switch Sl. Also,
Point 0 and point D are connected to ground 14 via switch S2. When detecting thread breakage, if a current is allowed to flow between points A and D, the following equation holds true for voltage E and detection voltage ■.

E-(RO+R, +r+R,)-I V -E -RO・■ Moreover, since R1+RZ = R, the following formula % Formula % As a result, the detected voltage V becomes a function only of the contact resistance r, The detection sensitivity is independent of the warp yarn breakage position. In this way, after warp thread breakage is detected and a stop signal is issued to the loom, first switch S2 is switched to
Current ■ between point and point C.

flow. At this time, the following formula holds true as above.

E'' (Ro +2R+ +r)' II Next, if the switches S, , and St are switched and current 2 is caused to flow between points B and D, the following equation also holds true.

E= (Re +2Rz +r)-II Now here, R
, - by setting -R%Rz = (1-k)R, the following equation can be obtained from the above equation.

-R1, -2·k-R = -RO-2(1-k) R 1°4RII xz From the above equation, the warp yarn breakage position k can be calculated by calculation without the influence of the contact resistance r.

Modifications of the Invention In the above embodiment, the arithmetic unit 11, the memory unit 12, and the output unit 13 are shown as dedicated circuit elements, but these can be replaced by the arithmetic/memory and display functions of a microcomputer, such as a display. It will be done. Further, the output device 13 is not limited to simply displaying the warp yarn breakage position, but may be combined with a device that automatically repairs warp yarn breakage, for example, and may instruct the device to the warp yarn breakage position.

Effects of the Invention In the present invention, when the dropper bar falls, the contact resistance between the dropper bin and the dropper bar is removed from the simultaneous relationship of equations at each end of the dropper pin, and the stop position of the dropper pin is calculated as an electrical quantity. Therefore, it is possible to accurately indicate the warp yarn breakage position regardless of the presence of contact resistance.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a dropper device and a warp breakage position indicating device of the present invention, FIG. 2 is a cross-sectional view of a portion of the relationship between the dropper pin and the dropper bar, and FIG. 3 is an equivalent circuit in Embodiment 1. 4 are equivalent circuit diagrams of the second embodiment, and FIG. 5 is an equivalent circuit diagram of the third embodiment. 1. Dropper device, 2. Warp thread breakage position indicating device, 3. Dropper pin, 4. Dropper bar, 5.
・Warp, 9a, 9b...Electrode, 10...Detector, 11
...Arithmetic unit, 12..Memory device, 13..Output device, 14.
・Earth, 15.16.17...Amplification circuit. Patent applicant Tsudakoma Kogyo Co., Ltd. Agent Patent attorney Kuni Nakagawa For horses Figure 1 Figure 2 Figure 3 Figure 5

Claims (3)

[Claims] (1) A dropper pin supported in an inserted state for each warp thread is dropped when the warp thread breaks, and the thread breakage state is detected by electrically contacting the dropped dropper pin between the electrodes of the dropper bar made of a resistor. In the dropper device, the detector is connected to at least both ends of the dropper bar and detects the amount of electricity from each end of the dropper bar to the dropping position of the dropper pin when the dropper pin is dropped, and a constant necessary for calculation. a memory device that stores in advance the warp yarn breakage position, a calculation unit that calculates the warp yarn breakage position using an arithmetic formula using a plurality of detected values from the above-mentioned detector, excluding the influence of contact resistance, and a calculation unit that calculates the warp yarn breakage position quantitatively based on the calculation result. A warp yarn breakage position indicating device comprising: an output device for indicating. (2) The warp yarn breakage position indicating device according to claim 1, wherein the detector has means for switching connection between a yarn breakage detection circuit and a position detection circuit. (3) The above memory stores the dropper bar length, resistance value,
The warp breakage position indicating device according to claim 1 or 2, wherein at least one resistance value per unit length is stored.