JPH01172732A - Hardness detecting apparatus - Google Patents

Abstract

PURPOSE:To make it possible to measure the hardness of a cigarette and the like accurately, by applying a specified strain difference or a specified load difference to a sample body, detecting a stress difference based on the specified strain difference or the strain difference based on the specified load difference, and detecting the hardness of the sample body. CONSTITUTION:Two rotary rollers 11 and 12 are fixed to the different positions so that the rollers are pushed to a sample A such as a cigarette. Specified strains x1 and x2 are applied to the sample A. The shafts of the rotary rollers 11 and 12 are linked to two load cells 21 and 22 as stress sensors. Stresses f1 and f2 for the strains x1 and x2 are detected with the load cells 21 and 22. The stress difference DELTAf(=f2-f1) is obtained with a subtracting device 3. Thus, the hardness of the cigarette and the like can be detected accurately.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a device for detecting the hardness of a test specimen, and is particularly suitable for use in cigarette manufacturing equipment to manufacture cigarettes with uniform hardness. The present invention relates to a hardness detection device.

[Conventional technology]

BACKGROUND ART Conventionally, in order to manufacture cigarettes with uniform hardness in a tobacco manufacturing apparatus, a hardness control technology has been developed that detects the hardness of a shredded tobacco stick and controls the amount of shredded tobacco filled.

Figure 11 shows the conventional tobacco shredding rod (hereinafter referred to as
It's called a cigarette. ) is a diagram illustrating a hardness detection method, where (a) is a diagram showing a hardness detection method based on the stress generated when a certain strain is applied to a cigarette; This shows the case where hardness is detected by the strain that occurs when .

In the same figure (al), a pressure rotating roller 61 that is pressed against a cigarette A is fixed at a fixed position by a pedestal 64 via a stress detection shaft 62 and a stress sensor 63.

Then, the cigarette A is pressed by this pressure rotating roller 61.
A certain strain is applied to the cigarette A, and the stress in the cigarette A is detected by a stress sensor 63, so that a detection signal corresponding to the stress can be obtained.

In addition, in the same figure (bl), a weight 66 is attached to the pressure rotating roller 61 via a magnetic core shaft 65, and a constant load is applied to the cigarette A by the pressure rotating roller 61.

A differential transformer 67, through which the magnetic core shaft 65 is penetrated and fixed at a fixed position by a pedestal 64, detects the displacement of the pressure rotating roller 61 from a predetermined reference point, and responds accordingly to the displacement. The detected signal is obtained as the distortion of the cigarette A with respect to a constant load.

Then, the hardness of the cigarette A is detected based on a detection signal corresponding to the stress for a constant strain or a detection signal corresponding to the strain for a constant load, and the cigarette is chopped and filled according to the fluctuation of the hardness. Amount controlled.

[Problem that the invention seeks to solve]

As mentioned above, in conventional manufacturing methods, when hardness is detected based on stress for a constant strain, a constant strain is applied to the cigarette using a single pressurizing rotating roller with a fixed position. For example, when the winding diameter of a cigarette changes and the position of the top surface of the cigarette changes, the strain imparted to the cigarette changes, making it impossible to accurately detect the hardness.

In addition, when detecting the hardness based on the strain under a certain load, the position of the pressure rotating roller etc. is measured from a predetermined reference position to detect the strain of the cigarette. For example, when the winding diameter of a cigarette changes, there is a problem in that the strain cannot be detected correctly and the hardness cannot be detected accurately.

An object of the present invention is to provide a hardness detection device that can accurately detect the hardness of a cigarette even if the roll diameter of the cigarette varies to some extent, especially in a cigarette manufacturing device.

[Means for solving problems]

The hardness detection device of the present invention, which has been achieved to achieve the above object, generates two detection signals according to the stress from the test object due to strain by applying strains with different displacements or different constant loads to the test object. Alternatively, a pair of detection means outputs two detection signals corresponding to the strain of the specimen due to the load, and a signal corresponding to the difference between the two detection signals corresponding to the stress or strain output by the pair of detection means. The present invention is characterized in that it comprises a subtraction means, and the hardness of the test specimen is detected based on a signal output by the subtraction means.

[Effect]

FIG. 1 is a diagram for explaining the present invention in detail, and FIG.
The figure shows an example of a device that detects hardness by detecting stress when a certain strain difference is applied (bl is an example of a device that detects hardness by detecting strain when a certain load difference is applied. It is a figure which each conceptually shows an example.

The device shown in Figure (a) consists of two rotating rollers 11.1.
2 are fixed at different positions so as to be in pressure contact with a specimen A such as a cigarette, and a constant strain Xl is applied to the specimen A.

x2 is given. The shafts of the rotating rollers 11.12 are respectively connected to two load cells 21 and 22 as stress sensors, and the stresses fi and f2 relative to the strain Xl*X2 are detected by the load cells 21.22,
A stress difference Δf (=f2 ft) is obtained by the subtractor 3.

In addition, in the apparatus shown in FIG. 6(b), different loads f1 and f2 are applied to the specimen A by two rotating rollers 11$12 each connected to a weight 6ss62, and a differential transformer is used as a strain sensor. 41.42, the displacement y1 of each rotating roller 1t*12. y2 is detected, and the subtracter 3 obtains the displacement difference Δy (=y2-y1).

The relationship between strain X and stress r in a specimen such as a cigarette is generally expressed by the curve f = F (
The strain difference ΔX with respect to the load difference Δf is a quantity representing the hardness of the specimen.

Now, suppose that the winding diameter, etc. of specimen A changes and the position of the top surface of specimen A changes by α, then specimen A shown in Figure 1 fa)
The distortions Xl and X2 are respectively x1+α.

x2+α, and the stress f1′ corresponding to the strain.

12' stress difference Δf' is Δf' = F (x2 + α) −F (x
t + α).

Therefore, the error ε for the stress difference Δf representing the hardness of the specimen
, Δf F (X2) F (xt)=1+
ε ・・・・・・・・・(1) If the relationship between strain X and stress f of the specimen is linear, for example, F (x)=kx (k is a constant), then
1, ε−〇.

Note that in the past, hardness was detected using the stress f obtained by a single sensor as an amount representing hardness, so the above formula (1
If we let the error ε′ correspond to 1, then.

Similarly to the above, when the relationship between strain X and stress f of the specimen is linear, ε = □ from the above equation (2).

In addition, the relationship between strain X and stress f of the specimen is nonlinear, for example, F
(x) −kx2 (k is a constant), then the old form (
From 1), X1+X2 From old formula (2), therefore, ε<ε', and the error is smaller than the conventional one.

Incidentally, when the winding diameter, etc. of specimen A changes and the position of its upper surface changes by α, the displacement y1. Since y2 both change by the same amount α, the displacement difference Δy is not affected by the amount of change α.

Moreover, since this displacement difference Δy becomes the strain difference ΔX on the specimen due to different loads f1tf2, the hardness can be accurately detected from this displacement difference Δy.

〔Example〕

FIG. 6 shows the process of manufacturing cigarettes using the hardness detection device according to the embodiment of the present invention, from the tobacco shredded supply section of the tobacco shredded winding machine to the stacking section, the rod-shaped forming section, and the wrapping paper glue. FIG. 7 is a diagram illustrating various steps leading to the next step, a filter mounting portion (not shown), via the attaching portion and the cutting portion.

The shredded tobacco A' is adjusted to a constant supply speed by the shredded tobacco supply drum 41 and transferred to the chimney 42, and then is sucked and accumulated under the porous metal endless tobacco band 43, and then transferred to the garniture tape 44. It moves onto the wrapping paper 45 that is fed out upwards and is gradually compressed with tongs 46 to form a rod-shaped body, and then passes through the wrapping paper gluing section 47 and then to the drying section 48.
The glue is fixed.

The glued stick-shaped cigarette is cut into a predetermined length by the cutting section 49. The cut cigarette A is subsequently transported at high speed on the transport rail 50, and during this time the hardness of the cigarette A is detected by a hardness detection device 10, 20 or 30 fixed to a frame (not shown). The filter 51 sends it to a filter mounting section (not shown) for the next step.

3 to 5 are diagrams showing respective embodiments of the hardness detection device of the present invention, which are used as the hardness detection device 10, 20 or 30 of FIG. 6.

In addition, in FIGS. 3 and 5, figure fa) is a front view,
Figure (bl is a side view.

FIG. 3 is a diagram showing an embodiment in which stress is detected by applying strain to a cigarette. In the figure, 11 is a rotating roller that comes into contact with the cigarette; 12 is a shaft that supports the rotating roller 11; It is designed to be in constant contact in this state.

13 is a load cell that detects stress and outputs a detection signal according to the stress; 14 is a load cell that holds the rotating roller 11 via the shaft 12 and transmits the upward stress applied to the rotating roller 11 to the load cell 13; The load cell 13 is fixed to a pedestal 16 by a connecting portion 15. Note that this pedestal 16 is attached to a frame of a cigarette manufacturing device.

These structures are provided in a pair as shown in FIG.
a allows fine adjustment of the vertical position of the rotating roller 11 and the like.

The pair of rotating rollers 11 are fixed at different heights and apply different strains to a cigarette (not shown), and the load cells 13 each output a detection signal corresponding to the stress caused by the strain. Then, the difference between the detection signals is obtained as an electric signal by a subtracter (not shown), and the hardness of the cigarette is controlled based on this electric signal.

In other words, as shown in the flowchart of the control system in Figure 7, the electric signal is amplified by a DC amplifier and continuously recorded on a DC recorder, and the electric signal is larger than the record of the standard hardness set by passing through the control setting device. (harder than standard), the control signal becomes negative, and the rotational speed of the shredded tobacco supply drum 41 of the winding machine shown in FIG. The amount of shredded tobacco packed in the cigarette is reduced to soften the hardness of the cigarette, thereby controlling the cigarette to a standard hardness.

On the other hand, if the electrical signal is smaller than the record of the standard hardness set (softer than the standard), the control signal becomes positive, and the rotational speed of the chopping supply drum 41 is increased to increase the amount of chopping to be filled into the cigarette. The hardness of the roll is increased and the hardness of the roll is controlled to be a standard hardness cigarette.

FIG. 4 is a diagram showing another embodiment in which the stress is detected by applying strain to a cigarette in the same way as described above, and shows a shaft 22. The stress from the cigarette is transmitted to the strain gauge type converter 2'i25 via the roller holder 23 and the slide block 24, and an output signal corresponding to the stress is obtained by the output of the strain gauge type converter 25. It is.

Also in this case, the strain gauge type transducer 25 is fixed to the pedestal 27 by the connecting portion 26, and the position adjustment screw 26a of the connecting portion 26 finely adjusts the vertical position of the rotating roller 21 and the like.

As described above with reference to FIG. 3, these structures are provided as a pair, and the heights of the rotating rollers 21 are set respectively, and different strains are applied to the cigarette.
A detection signal corresponding to the stress is output from the strain gauge converter 25.

FIG. 5 is a diagram showing an embodiment in which strain differences are detected by applying constant different loads to cigarettes.

In the figure, 31 is a rotating roller that comes into contact with the cigarette, 32 is a shaft that pivotally supports the rotating roller 31, and 3
3 is a roller holder that holds the rotating roller 31 by a shaft 32, 34 is a core shaft connected to the roller holder 33, and 35 is a differential transformer. It is inserted into the transformer 35.

Then, an output signal corresponding to the amount of vertical displacement of the core shaft 34 is output from the differential transformer 35.

A weight 36 is detachably attached to the core shaft 34, and the weight 36 presses the rotating roller 31 against a cigarette (not shown). Note that the differential transformer 35 is attached to a fixing member 38 by a transformer holder 37, and this fixing member 38 is further attached to a pedestal 39.

These structures are provided in a pair as shown in FIG.
a allows fine adjustment of the vertical position of the differential transformer 35 and the like.

Furthermore, in this pair of mechanisms, weights 36 of different weights are used, so that the loads applied to the cigarettes or the like by the rotating rollers 31 are different.

These different loads cause different strains on the cigarette, etc., and a detection signal corresponding to the displacement caused by the mustard is output from the differential transformer 35. The difference between the detection signals is obtained as an electric signal by a subtracter (not shown). The hardness of the cigarette is controlled based on the electrical signal.

In this case, when the hardness of the cigarette becomes softer than the standard hardness, the strain difference increases and the obtained electrical signal increases, and when the cigarette becomes hard, the strain difference becomes smaller and the electrical signal decreases. Contrary to the case in which the hardness is detected by the apparatus described with reference to FIG. 4 and FIG. 4, the increment amount may be controlled by setting a control signal.

Figure 8 is a diagram showing an example of the relationship between the displacement (strain) and stress of a cigarette roll, and as can be seen from the figure, when the displacement is in the range of 0 to 2, the condition is close to a quadratic curve. However, the displacement that occurs in the cigarette manufacturing process as mentioned above is 0.
~1 dragon, and in the range of 0 to 1 dragon, it can be regarded as a substantially straight line.

Therefore, as described above, it can be seen that the hardness detection device of the present invention can detect substantially accurate winding hardness.

FIG. 9 is a diagram showing the relationship between displacement and stress for a dummy made of rubber or the like formed into a roll shape instead of a cigarette roll. In this case and in the case of the cigarette shown in FIG. 8, the stress values for the same amount of displacement are different, but in the case of this FIG. 9 as well, there is a nearly linear relationship.

The dummy is run in the same manner as a cigarette in the cigarette manufacturing process, and the bottom part of the dummy is made to have a thickness of 0.
．． 4■ By arranging 1 and 0.8n liners and setting them in a state that corresponds to changes in the winding diameter, we investigated the relationship between the dummy strain difference ΔX measured by the hardness detection device and its stress difference Δf.
The results shown in FIG. 10 were obtained. In addition, the same figure (a
) shows the case when the car was running at 500 m/min, and (b) shows the case when the car was running at 100 m/min.

As shown in the figure, the strain difference ΔX and the stress difference Δf have a line type relationship, although they differ somewhat depending on the running speed, and
Since the variation in the stress difference corresponding to the change in the winding diameter, that is, the variation in the stress difference Δf for the same strain difference ΔX, is small, it can be seen that substantially accurate hardness can be detected during this traveling as well.

In the above embodiments, the hardness detection of cigarettes has been mainly described, but the hardness of cigarette filters, other rod-shaped bodies, flat plates, etc. can also be measured.

Further, it goes without saying that the hardness detection device of the present invention can be used as an independent device such as a winding hardness measuring device.

〔Effect of the invention〕

As explained above, according to the present invention, a constant strain difference or a constant load difference is applied to a test specimen, and the stress difference due to the constant strain difference or the strain difference due to the constant load difference is detected to determine the hardness of the test specimen. Since it is detected, the hardness of cigarettes, etc. can be accurately measured.

Furthermore, as shown in the examples, if the hardness detection device of the present invention is used, control can be performed to manufacture cigarettes with uniform hardness even when the roll diameter changes in cigarette manufacturing equipment. You can do it like this.

[Brief explanation of the drawing]

Fig. 1 is a diagram explaining the present invention in detail, Fig. 2 is a diagram showing the relationship between strain and stress of a specimen suitable for the hardness detection device of the present invention, and Figs. 3 to 5 are diagrams according to the present invention. Figure 6 is a diagram illustrating the process of manufacturing cigarettes using the hardness detection device of the example, Figure 7 is a diagram showing the control system in the cigarette manufacturing process of Figure 6. Figure 8 is a diagram showing an example of the relationship between the displacement and stress of a cigarette roll, Figure 9 is a diagram showing the relationship between displacement and stress for a cigarette dummy, and Figure 10 is a diagram showing an example of the relationship between displacement and stress for a cigarette dummy. FIG. 11 is a diagram showing the results of one experiment. FIG. 11 is a diagram showing a conventional example of cigarette hardness detection. 1...Rotating roller, 2...Stress sensor, 3...
Subtractor, 4... Strain sensor, A... Specimen.

Claims (1)

[Claims] Applying strains with different displacements or different constant loads to the test specimen, and generating two detection signals corresponding to the stress from the test specimen due to the strain or two detection signals corresponding to the strain of the test specimen due to the load. a pair of detection means for outputting a detection signal; and a subtraction means for outputting a signal corresponding to the difference between the two detection signals corresponding to the stress or strain output by the pair of detection means, the subtraction means outputs 1. A hardness detection device, characterized in that the hardness of a test specimen is detected based on a signal.