JPS58192716A - Method for safe operation by setting allowance of slant cut - Google Patents

Abstract

PURPOSE:To make the operation safe, by detecting, when slant of a band saw has exceeded the allowance, the fact, stopping the operation of cutting, and issuing the notice. CONSTITUTION:A slanted cut detecting mechanism 39 is attached to a saw blade guide apparatus 29 between a material 37 to be cut and a driving wheel 7. If a saw blade 3 slants to the right or left, the displacement of the lower end of the barrel section can be accurately detected. If it slants forward, the size becomes insufficient, while it slants backward, the size becomes excess. If the slant exceeds a certain limit, the cutting is stopped, and notice is given.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safe work method by setting an allowable amount of cutting and bending.

Originally, a band saw blade has a band saw blade guide device that clamps and guides the body of the band saw blade before and after the band saw blade passes through the material to be cut. It is regulated to match the cutting direction.

However, if the band saw blade's cutting performance deteriorates or the material to be cut is abnormally hard or has uneven hardness, the effective cutting action of the band saw blade against the cutting speed of the band saw blade will be reduced, and the band saw blade will As described above, by resisting the applied tension force, the posture of the band saw blade is made to match the direction of the cut, and the band saw blade deviates from a certain state and begins to twist and fall.

For example, when a cylindrical workpiece is repeatedly cut into a fixed length using a so-called fully automatic horizontal band saw, if the above-mentioned adverse conditions are applied, the upper and lower positions of the cylindrical shaft core may be cut when viewed from above. When the band saw blade is cut, a polygonal cutting line can be seen where the tooth tip or back of the band saw blade makes the longest detour, and at that position, the band saw blade twists and moves in a tilted position.

This is the cutting bending phenomenon.As the band saw blade circulates and performs continuous cutting, the setting teeth that fall down and occupy a low position wear out quickly, and the tendency to set one side rapidly progresses, further promoting the cutting bending. be.

In recent years, unmanned work using fully automatic machines has been actively carried out, and cutting work is no exception, but it is necessary to have a system that automatically stops the cutting work and issues an alarm when the cut exceeds a certain tolerance limit. There's no need to explain.

The above is a series of defective products that were supposed to be cut perpendicular to the axis when viewed in the direction of movement of the bandsaw blade, but instead became parallelograms cut at the same angle in the inclination direction one after another. I mentioned the danger of this happening, but when you stand in front of the cutting machine and look at it, the material to be cut is thicker at the bottom, in other words, when the tip of the tooth is located further back than the back of the band saw blade. As the bending progresses, the stored force of the band saw blade, which is an elastic body, causes the cut pieces of the product to be stretched forward at the moment of separation, causing injuries to employees. There was also a danger that this could happen.

Conventionally, in preparation for the above-mentioned dangers, a method was used in which the allowable cutting and bending amount was calculated and set in advance by the worker for each cutting operation, but this required a considerable amount of experience and was not satisfactory. Ta.

The feature of this Komei is that it sets a constant value regardless of the size of the material to be cut, so that all cutting work falls within the allowable cutting and bending limit, and prevents the occurrence of cutting and bending that exceeds the allowable cutting and bending limit. The present invention provides a safe work method that immediately stops cutting and issues an alarm.

First, a mechanism for detecting the amount of cutting and bending will be explained based on FIG. 1.2.3.

The so-called horizontal band saw 5J1 shown in FIG.
The housing plate 13 is rotatably parallel to the housing plate 13, and is driven to swing around a horizontal shaft 17 provided on a part of the base 15 by a swing cylinder 19.

The band saw blade 3 described above is moved and tensioned by moving the driven wheel 7 away from the driving wheel 5 by the handle 21, and is installed at the lower ends of two guide arms 23 and 25 provided at the front. Saw blade guide device 27.2
9 on a cutting plane 31 parallel to the swinging direction of the housing plate 13.

, town.

Therefore, in the case of the illustrated horizontal band fIA1111, the plane occupied by the band saw blade 3 between the two left and right saw blade guide devices 27, 29 coincides with the cutting plane, and the plan view C shown in FIGS. 31, so the same reference numerals are used.

Thus, when the housing plate 13 swings downward, the band saw blade 3 between the left and right saw blade guide devices 27 and 29 picks up the workpiece 37 that is clamped and fixed between the fixed vice jaw 33 and the movable vice jaw 35 on the machine base 15. Cut at right angles to the axis.

2.3 shows an embodiment in which a cut bend amount detection mechanism 39 is attached to the saw blade guide device 29 between the workpiece 37 and the drive wheel 7.

The saw blade guide device 29 is attached to the guide arm 25 so that its position can be adjusted and fixed up and down, and includes a carbide block 41 that clamps and guides the body of the band saw blade 3 on both sides, and a seesaw set backup roller that regulates the back of the band saw blade 3. '13, and the band saw blade 3 held vertically by the saw blade guide device ff129 is driven by the drive wheel 5.
Uneven roller 4 that assists and guides twisting toward
5 is provided.

At the side end of the material to be cut 37 of the saw blade guide device 29, a shaft body 4 parallel to the traveling direction of the band saw blade is installed at a position slightly above the back of the band saw blade 3.
7 is fixedly installed, the shaft 47 is vertically fixed, and a column 51 having a screw portion 49 is fixed vertically, and a magnetizing body 53 such as a permanent magnet is fixed to the top of the column 51.

A thick rectangular cylinder 55 is provided which engages with the above-mentioned shaft body 47 and can freely rotate around it, and a shaft 59 that rotatably holds a roller 57 having a large diameter at the lower end of the outer periphery is fixed to the lower end, Above the thick square tube 55 is a bullet v161 between it and the saw blade guide table @29.
The above-mentioned roller 57 is configured to come into pressure contact with the body of the band saw blade 3 with a It is.

Furthermore, the upper part of the thick rectangular tube 55 is covered with a hollow lid member 63, and a magnetic detector 65 is fixed to the hollow part, and a conductive wire 67 extends through the ceiling of the lid member 63 as shown in the figure. Connected to the omitted measuring device.

The detected value of the amount of magnetic force is maximum when the cores of the magnetizing body 53 and the magnetic detector 65 are aligned, for example, and the magnetic detector 65 attached to the lid member 63 is in contrast to the stationary magnetizing body 53. The structure is such that it is possible to accurately detect the decrease in the absolute value of the detected value when the alignment changes as shown in FIG. 2 by swinging from side to side.

In this way, even if the bandsaw blade 3 shown in FIG. 2 is tilted to the left or right from the vertical position, the displacement of the lower end of the body can be accurately detected.

Next, with reference to FIGS. 4 and 5, the actual state of the allowable limits regarding the amount of cutting and bending in a bandsaw machine and the height of the material to be cut will be described.

Band saws are generally used to cut long materials such as round bars, prismatic columns, and shaped steel into desired dimensions and lengths, and to prepare materials for machining without causing heat effects. Therefore, it must be cut to a size that includes machining allowance, but
The dimensional tolerance is usually that cutting and bending of up to 1.5% of the width is allowed. In addition, when cutting and bending, the band saw blade is guided vertically at a distance in the forward and backward directions of the saw blade across the material to be cut, and while the cutting pressure is applied to the material to be cut, the material to be cut has a reaction force. This is thought to occur because the blade is lifted up and moved around against the tension, causing the blade to fall with the tooth tip forward, or the tooth tip to turn backward and try to fall over. Taking a round bar as an example, it occurs on a vertical line passing through the center.

In consideration of the above-mentioned phenomenon of occurrence of cut bending, as shown in Fig. 4, the material to be cut 37 is made into a round bar, the diameter is d, and the band saw blade is held vertically by the left and right band saw blade guide devices 27 and 29. Let the inner end distance of the carbide block 41 be the span distance m1 (S),
The distance from the inner end of the carbide block 41 of the saw blade guide device 29 between the workpiece 37 and the drive wheel 5 to the foot of the perpendicular line drawn from the central axis of the workpiece to the bistable is defined as X.
, the distance from the inner end of the carbide block 41 to the contact point of the roller 57 that is pressed against the body of the bandsaw blade of the cut bending amount detection device 39 and the inner end of the carbide block 41 is defined as a, and the vertical distance from the central axis of the material to be cut 37 is If the maximum displacement of either the upper or lower end of the bandsaw blade on the line is b, and the amount of displacement detected by the above-mentioned [''-ra 57 is C, then a right triangle with a and C as two sides, and b and X are Since the right triangles having two sides are similar, a/c=x/b,', c=a-b/x.

Now, using an experimental machine where the distance a is actually 16111111, the amount of displacement at the contact roller position for a round bar from 100φ to 250φ is calculated by assuming that the allowable cutting bend amount is 1.5% of the height of the material to be cut. When calculated, Table 1 shows <1) to (5).
).

Table 1 (+>, using the numbers in (3), a=16.
Using c-0,358 to calculate r c=a-b-/X is (6), and calculating what percentage of (1) corresponds to (6) is (7). ).

Accordingly, from Table 1, if you specify 0.358mm, which is the allowable cut/bend detection amount when cutting 100φ, as the safe cutting limit for the control equipment, all materials to be cut with a diameter larger than 100φ will be cut. The displacement 1b' at the axis position where the maximum cutting bend occurs is 1.
It turns out that the enjoyment is less than 50%.

Table 1 (Unit: (IH6) 11111.
(7) %) Figure 5 illustrates the above relationship.
If the detection device is set to stop cutting due to cutting and bending at a displacement of ゜5Qmm, that is, a displacement of 0.358mm at the detection part, 2
In the case of 50φ cutting, the actual displacement amount is 3.177 mm, indicating that the cutting stop due to cutting and bending is activated at 1.27% of the height of the material.

Figure 6 is a block explanatory diagram showing the relationship between the control devices, and although there is no need to specifically explain it, the bending that occurs during cutting when the housing of the band saw machine is lowered is directed toward the front when viewed from the front of the machine. There are cases in which the product is cut and bent (called negative cutting and bending because the product is cut to insufficient dimensions) and cases in which the product is cut and bent in the tangential direction (positive cutting and bending), and when cutting and bending in both directions reaches a certain limit, The cutting is stopped, the housing immediately rises and stops, and an alarm is issued.

In the embodiment of the present invention described in detail above, by setting a control limit for the displacement amount at the displacement detection position of the material to be cut with the smallest cutting height when cutting with the band saw machine, all This allows the cutting operation to be carried out without producing defective products without having to reset the set values each time the material to be cut is cut. In addition, even if you forget to move the saw blade guide device, which is located in the direction of saw blade movement from the material to be cut, each time you change the material to be cut to a smaller material, the method of the present invention detects the occurrence of a bend in the cut and operates. It's also effective.

Note that the method of the present invention is not limited to the so-called horizontal bandsaw machine, and can be performed unmanned. It is clear that this method can also be used for all bandsaw machines that perform cutting operations.

[Brief explanation of the drawing]

Fig. 1 is a front view of a so-called horizontal bandsaw machine as an example of implementing the present invention, Fig. 2 is a view from the ■-■ arrow in Fig. 1, Fig. 3 is a front view of Fig. 2, and Fig. 4 is a An explanatory diagram of the symbols in Table 1, Figure 5 is an explanatory diagram showing the relationship between the displacement amount and the center cutting displacement amount of 250φ cutting when the cutting displacement amount when cutting 100φ is set to the correction limit, and FIG. 6 FIG. 1 is a 10-step diagram explaining the equipment of the control device of the present invention.
(-Explanation of symbols representing main parts in the drawings 1...Horizontal band saw machine 3...Band saw blade 29...Saw blade guide @31...Cutting plane (station line) 37...To be cut Material 39... Cutting and bending amount detection mechanism 47...
Shaft body 53...Magnetic body 55...Thick square tube
61...Munition 65...Magnetic detector patent applicant Amada Co., Ltd. 4τ 11m Figure 4 Figure 5

Claims (1)

[Claims] A safe work method by setting constant the displacement Il (allowable cutting bending amount) of the guided band saw blade from the running position due to the torsion of the body of the band saw blade between the material to be cut of the band saw machine and the band saw blade guide device. .