JPS6190038A - Instrument for measuring hardness of winding roll - Google Patents

Abstract

PURPOSE:To obtain a measuring instrument with high reliability, durability, operability and little room for an individual difference to stand in by detecting an electric variation corresponding to the displacement of a rotating magnetic substance linking with rebounding motion taking place from the falling of weight. CONSTITUTION:The weight 12 is connected with a magnetic substance drum 13 via an arm 11 and constituted rotatably with a point P, separated from its center P2 as a fulcrum and held at the prescribed height. Further, inductance coils 15, 16 are arranged fixedly at both the sides of the drum 13 with it in-between. Then, when a stopper 14 is released, the weight 12 falls freely, inflicts the first impact on the surface of the winding roll 4, rebounds up to a certain height by resiliency corresponding to hardness of the part, and then while again repeating the fall, impact and rebound, its movement attenuates and comes to a standstill finally. The variation of inductance by this drum 13 actuating as an armature is converted into an electrical signal in a phase detection circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hardness measuring device for measuring the hardness of a winding roll. The device according to the present invention is used, for example, to measure the hardness of rolled products such as paper, thread, cloth, plastic film, metal foil, etc.

1 [Prior art and problems] Conventionally, the common methods for measuring and evaluating the winding hardness (hereinafter referred to as hardness) of a take-up roll of plastic film, etc. have been the percussion method using a club and the Test methods include the Schmidt paper roll test and hammer test.

The former is a method in which the hardness of the take-up roll is determined by hitting the take-up roll at some point along its surface length with a club or the like and based on the impact, repulsion, sound, etc. generated at that time. Although this method is praised as a simple method, it is highly dependent on the five human senses, requires skill, is susceptible to individual differences, and expresses the results of the percussion numerically. Therefore, quantitative evaluation is impossible.

The latter method began to be used in the paper manufacturing and related industries more than ten years ago, and is now widely used as a general hardness testing method. The Paper and Pulp Technology Association adopted this method as a method for testing web paper hardness in February 1981 (J,
TAPPI paper pulp test method No. 37-81).

However, the latter Schmidt paper roll test
The hammer is a repurposed model of the Schmidt Concrete Test Hammer, which was developed for testing the hardness of concrete, and is used for lightweight concrete. This is originally a tester for measuring the hardness of solids, so it can be used as a measuring device to measure the hardness of a take-up roll made of laminated sheets. However, there are still some aspects that are unreasonable in terms of work efficiency, individual differences in measured values, etc.

[Means for solving problems]

The present invention is highly reliable, durable, and easy to operate, has very little room for individual differences between measurers, and has high correspondence between measured values and the actual hardness and hardness profile of the object to be measured. An object of the present invention is to provide a winding roll hardness measuring device that enables good measurement of the winding roll, and the means thereof is a winding roll hardness measuring device, the device having one end as a fulcrum. A rotary magnetic drum with a weight of a predetermined weight provided at the other end of the arm and the fulcrum of the arm set at an eccentric position and fixed at a predetermined angle, the weight being attached to the object to be measured. An appropriate air gap is provided between the rotating magnetic drum and the rotating magnetic drum, which performs eccentric movement around the fulcrum in response to the bouncing motion caused by the free fall. A bounce detection means includes a pair of detection means disposed facing each other and detects an electrical change corresponding to the displacement caused by the eccentric movement, and an electrical change occurring in each of the pair of detection means A detection circuit is provided for each detection means in order to detect a change, and the detection output obtained by adding the detection outputs obtained by the detection circuit with mutually opposite polarities is manually added and detected. A phase detection circuit having a differential amplifier circuit for amplifying and outputting a detection output corresponding to a differential electric hand change for each of the pair of detection means, and a balanced voltage set by the phase detection circuit. a reference point detection circuit that detects an electrical reference point at the start of the rebound operation;
A phase detection means including a timer that turns on a switch for a predetermined time from the reference point, and an amplifier circuit that amplifies the output of the phase detection circuit to a voltage that can be recorded, and from the amplifier circuit of the phase detection means. The positive side and negative side peak hold circuits provided to store the absolute values of the peak values for each of the positive side and negative side of the output, and the positive side peak hold circuit and the negative side peak hold circuit are added together. The present invention is characterized by comprising an addition means including an addition circuit that outputs an electrical absolute value of the cough rebound motion.

Embodiment FIG. 1 is a block diagram showing an embodiment of a winding roll hardness measuring device according to the present invention. In FIG. 1, the rebound detection means 1 includes a disc-shaped weight 12 of a predetermined weight provided at one end of an arm 11, and a fulcrum P, which is the other end of the arm. A rotating magnetic drum 13 is provided at a position eccentric from the center P2 and has an arm 11 fixed at a predetermined angle, a stopper 14 supports a position near the middle of the arm 11, and the magnetic drum 13 is connected to a weight 12. In order to perform eccentric movement around the fulcrum P1 in response to the bouncing movement caused by free falling onto the object to be measured, which is a take-up roll, and to detect changes in inductance caused by the eccentric movement. , a pair of coils 15 and 16 arranged opposite to each other with an appropriate gap provided on both sides of the magnetic drum 13.

The phase detection means 2 includes a detection circuit 212 using an ideal diode to detect a change in voltage caused by a change in inductance occurring in each of the pair of coils 15 and 16.
．． 213 (see FIG. 3), an oscillator 211 that oscillates, for example, 5 KHz to superimpose on the voltage, and the detection circuit 2.
A phase detection circuit 21 having a differential amplifier circuit 214 that adds and outputs the outputs of 12 and 213, and the rebound shown in FIG. 4 based on the balanced voltage adjusted by the variable volume VR of the phase detection circuit 21. A reference point detection circuit 22 detects the electrical reference point P at the start of operation, a timer 23 turns on the switch 24 only for a valid period of time for measurement from the reference point P2, and the output of the phase detection circuit 21 is transmitted to, for example, a pen recorder. It is composed of an amplifier circuit 25 that amplifies the voltage to a voltage that can be recorded on a display device (not shown) such as the above.

The addition means 3 includes a positive side (plus) peak hold circuit 31 that holds the absolute value of the peak value for each of the upper positive side and the lower negative side of the output of the amplifier circuit 25 with respect to the electrical reference point as a boundary. and a negative side (minus) peak hold circuit 32, and an adder circuit 33 that adds both.

The output of the adder circuit 33 is used for monitoring as a peak-to-peak output, and the output of the force amplification circuit 25 is recorded on a pen recorder or the like as an output corresponding to the rebound motion, and is recorded as hardness measurement data of the winding roll. Ru.

FIG. 2 (a+, (bl) is a block diagram illustrating the rebound detection means shown in FIG. 1 in more detail. In FIG. 2, the weight 12 is connected to the magnetic drum 13 via the arm 11, and The body drum 13 has a rotatable structure with a point P1 apart from the center P2 as a fulcrum, and is held at a constant height.Furthermore, the magnetic drum I3 is flattened and an inductance coil 15 and an inductance coil 16 are installed on both sides thereof. are fixedly arranged, and appropriate gaps are provided between the magnetic drum I3 and the inductance coil 15 and between the magnetic drum 13 and the inductance coil 16, respectively.

Now, when this mechanism is placed at the planned measurement point on the top surface of the take-up roll 4 which is standing still with its axial direction horizontal, and the stopper 14 is released, the weight 12 installed at the tip of the arm will fall freely and The first blow is given to the surface, and it bounces up to a certain height due to the repulsive force corresponding to the hardness of that spot, and then falls, hits, and bounces again, and the movement attenuates until it finally lands on the take-up roll 4. Stand still. FIG. 4 shows the rebound behavior of the weight 12. As shown in FIG. 4, the behavior of the weight 12 during the first impact will be described in detail.The weight 12 falls freely, reaches the surface of the take-up roll 4, and hits it, and the impact force causes the weight to fall. By giving a deformation to the part according to the hardness of that part, it sinks a little from the surface of the take-up roll 4, and at that time, it is repelled by the repulsive force received from that part according to the hardness of that part, and rises. and reaches the top point, where it begins its free fall again.

If the area is relatively soft, the deformation is large, and therefore energy is absorbed from the weights 1-2, so the weights 12 lose energy and the amount of rebound is relatively small. In a relatively hard location, the deformation is small, the energy lost by the weight 12 is also small, and the amount of rebound is relatively large.

Based on the above phenomenon, when determining the amount of rebound corresponding to the hardness at the measured location of the take-up roll, the reference point for rebound is set as follows.

In other words, in the conventional general hardness test and take-up roll hardness tester, the reference point for measuring the rebound height is the surface of the object, which is unavoidable due to its mechanism, but based on the above explanation, As is clear from the above, the surface of the object to be measured after the weight 12 hits the object is already just a point that the weight 12 passes through before it is repelled and reaches the highest point. The weight 1-12 gains energy from the repulsive force of the object to be measured and starts to rise, and by the time it passes the surface, the weight 12 has already consumed part of its energy, so the amount of rebound is reduced between the surface and the top point. Whether calculated or determined, this can be the true value of the rebound.From the final point of the deformation that the weight 12 gives to the measured location, that is, the lowest point a of the weight 12's sinking, to the highest point of the rebound, a2. The amount of rebound achieved indicates the true rebound value. In the measuring device of the present invention, the lowest point a of the weight 12 sinks due to the first impact, and the highest point a2 of the rebound.
The amount of rebound that results in this is calculated and displayed as a hardness value.

The first important feature of the present invention is the weight 1 as described above.
In order to ensure that the sinking and rebounding behavior of the winding roll 2 is controlled only by the hardness of the winding roll 4, the magnitude of the impact force applied to the winding roll 4 is adjusted so that there are no individual differences and that the strength of the winding roll 4 is controlled at the time of measurement. Its purpose is to keep the hardness constant without changing it.

The impact force in this device is determined by only three factors: the length of the arm 11, the weight of the weight 12, and the distance, or height, between the free fall starting point of the weight 12 and the impact point on the take-up roll 4. Moreover, since these three elements are completely unaffected by changes in characteristics over time or due to repeated fatigue, the values of the three elements can be adjusted in advance according to the condition of the take-up roll 4. If set to a certain value, it is possible to always apply a constant striking force in repeated measurements.

The second feature is the arm 1 to which the weight 12 is attached.
The object of the present invention is to convert the rebound behavior into an electrical signal without affecting the rebound behavior at the time of the rebound behavior. A magnetic drum 13 that operates as an armature with respect to the inductance coil 15 and the inductance coil 16 is attached to the base of the arm 11, and a point P1, which is offset from the center of the magnetic drum 13, is used as the rotation fulcrum of the arm 11. By this, the inductance coil 15 and the inductance coil 16 and the magnetic drum 1
This is a change in the inductance of the inductance coil 15 and the inductance coil 16 that occurs due to the mechanism in which each gap between the inductance coil 15 and the inductance coil 16 changes relatively depending on the rebound behavior of the weight 12 and the rotation angle of the arm 11. The amount of change in inductance is converted into an electrical signal in the phase detection circuit 21.

Furthermore, as a third feature, in the method using this device, the amount of rebound from the lowest point a to the highest point a2 of the first rebound of the weight 12 caused by the first impact shown in FIG. 4 is measured on the winding to be measured. The inductance coil 15 and the inductance coil 16 between the lowest point a1 and the highest point a2 of the first rebound of the weight 12 are treated as corresponding to the hardness at the measured point of the take-up roll. The amount of change in relative inductance that occurs is converted into an electrical signal.As shown in Fig. 5, an arbitrary point within the rebound range is set as an electrical reference point P3, and the electrical signal is From the reference point to the top (+
) electrical signal, the lower part is (-) electrical signal, (+) electrical signal is led to (+) peak hold circuit 31, (-) electrical signal is led to (=) peak hold circuit 32, and the maximum value of both is absolute. By storing the hardness as a value and adding the two in an adding circuit 33, an electric signal corresponding to the hardness is output.

Furthermore, as a means for displaying or recording the output of the electrical signal as the hardness of the winding roll to be measured, a digital display, a printer, a recorder, etc. or a combination thereof may be attached as necessary. The hardness at each measurement point of the winding roll to be measured can be displayed, read or recorded, or recorded as a hardness profile.

FIG. 3 is a circuit diagram illustrating the phase detection circuit 21 shown in FIG. 1 in more detail. In FIG. 3, a common contact point P4 between the coil 15 and the resistor R1 and a common contact P4 between the coil 16 and the resistor R2 are shown.
The change in voltage occurring at the common contact point P with the terminal is detected by the subsequent detection circuits 212 and 213. In this case, the oscillator 211 oscillates a sine wave or square wave of, for example, 5 KHz and superimposes it on the voltage change, and the variable volume VR
The midpoint of impedance including RI and R2 is set by . Detection circuits 212 and 213 are operational amplifiers A.

and A2, and diodes D+, Dz and R.

This is an ideal diode detection circuit composed of D, which solves temperature drift caused by environmental changes. As shown in the figure, the positive output of the detection circuit 212 and the negative output of the detection circuit 213 are added together via their respective resistors, while the positive output of the detection circuit 213 and the negative output of the detection circuit 212 are are added via each resistor.

These are amplified by the differential amplifier circuit 214, and the coil 15
, 16 differentially varying inductances are obtained.

FIG. 6 is a block diagram showing another embodiment of the bounce detection means shown in FIG. 1. In FIG. 6, the magnetic drum 13
Electrodes 61 are placed at opposite positions with appropriate gaps on both sides of the
and 62 are arranged.

It is detected that the capacitance between the magnetic drum and each of the electrodes 61 and 62 changes due to the eccentric movement of the magnetic drum. Changes in capacitance are detected by the aforementioned phase detection circuit in the subsequent stage.

FIG. 7 is a configuration diagram showing still another embodiment of the bounce detection means shown in FIG. 1. In FIG. 7, a light emitting means 71 such as a lamp suitable as a light source is provided on one side of the magnetic drum 13, and the light rays from the lamp 71 are reflected by suitable reflection plates 72 and 73. The light is received by appropriate light receiving means 74 and 75. In this case, the shielding plate 76
, 77 are provided to prevent light from other sources. The change in the amount of light passing through the gap between the magnetic drum 13 and the shielding plates 76, 7'7 caused by the eccentric movement of the magnetic drum 13 is detected by a phase detection circuit in the subsequent stage.

Effects of the Invention As is clear from the above description, the hardness measuring device of the present invention can be used to measure and evaluate the hardness of winding rolls of paper, thread, cloth, plastic film, metal, etc. A means for always applying a constant impact force to the take-up roll when measuring hardness at some point on the surface length of the take-up roll, and the absolute value of the amount of rebound caused by the impact force. By providing a means for converting into an electrical signal and a means for displaying or recording the converted electrical signal as the absolute value of the peak value, the method is easy to manufacture and has more accuracy and sufficient reproducibility than conventional methods. The measured values obtained in this way and their profiles thus correspond well to the evaluation of the hardness of the winding roll. In addition, in this explanation, paper, thread,
A take-up roll made of cloth, plastic film, metal, etc.

Although mainly explained, since the measuring device of the present invention quantitatively measures and displays or records the repulsive force corresponding to the hardness of an object, it can be used not only for laminates including take-up rolls but also for metals. It can be applied to the measurement of the hardness of elastic bodies such as rubber and flooring materials as well as ceramic products.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the winding roll hardness measuring device according to the present invention, and FIGS. 2(a) and lb) are front and side views showing details of the bounce detection means shown in FIG. Figure 3 is a detailed circuit diagram of the phase detection circuit shown in Figure 1. Figure 4 shows the time and amount of rebound when the weight of the bounce detection means shown in Figure 1 falls freely onto the object to be measured. The diagram shown in FIG. 5 is the fourth phase obtained by the phase detection means shown in
6 is a block diagram showing another embodiment of the rebound detection means shown in FIG. 1, and FIG. 7 is a diagram showing still another embodiment of the rebound detection means shown in FIG. 1. FIG. 2 is a configuration diagram showing an example. (Explanation of symbols) 1... Rebound detection means, 2... Phase detection means, 3... Addition means, 4... Measured object, 11... Arm, 12... Weight, 13. ... Rotating magnetic drum, 14... Stopper, 15, 16... Detection means, 17... Fulcrum bearing, 18... National body base, 21... Phase detection circuit, 22... Standard inspection Output circuit, 23...Timer, 24...Switch, 25...Amplification circuit, 31...Plus peak hold circuit, 32...Minus peak hold circuit, 33...Addition circuit, 61, 62 ...electrode, 71...light emitting means, 72, 73...reflecting plate, 74, 75...light receiving means, 76, 77...shielding plate, 211...oscillator, 212, 213...・Detection circuit, 214... Differential amplifier circuit.

Claims (1)

[Claims] 1. A winding roll hardness measuring device, which includes a weight of a predetermined weight provided at the other end of an arm with one end as a fulcrum, and the arm. A rotating magnetic drum with the arm fixed at a predetermined angle with the fulcrum set at an eccentric position, the weight being centered around the fulcrum in response to the bouncing movement caused by free falling onto the object to be measured. and a pair of detection means arranged facing each other with an appropriate gap provided between the rotating magnetic drum and the rotating magnetic drum on both sides of the rotating magnetic drum. a bounce detection means that detects an electrical change in response to a displacement caused by movement, and a detection provided for each detection means to detect an electrical change that occurs in each of the pair of detection means; The detection outputs obtained by adding the detection outputs obtained by the detection circuit and the detection outputs having opposite polarities to each other are inputted to each detection circuit, and the detection outputs obtained by adding together the detection outputs obtained by the detection circuit are inputted, and a differential electrical change is generated for each of the pair of detection means. A phase detection circuit having a differential amplifier circuit that amplifies and outputs a corresponding detection output, and reference point detection that detects an electrical reference point at the start of a rebound operation based on a balanced voltage set by the phase detection circuit. a phase detection means including a circuit, a timer for turning on a switch for a predetermined time from the reference point, and an amplifier circuit for amplifying the output of the phase detection circuit to a voltage that can be recorded; positive side and negative side peak hold circuits provided to store the absolute values of peak values for each of the positive side and negative side of the output from the amplifier circuit;
A take-up roll comprising: an adding circuit that adds both the positive peak hold circuit and the negative peak hold circuit and outputs the result as an electrical absolute value of the rebound operation. hardness measuring device. 2. The device according to claim 1, wherein the detection means comprises a coil for detecting a change in inductance. 3. The device according to claim 1, wherein the sensing means comprises an electrode for detecting a change in capacitance. 4. The detection means includes a light emitting means as a light source, a pair of reflecting plates that reflect the light rays from the light emitting means in a predetermined direction, a light receiving means that receives the light rays from the reflecting plate, and a light receiving means that prevents light from entering from other sources. 2. The device according to claim 1, further comprising a shielding plate for preventing.