JP2001143915A - Non-inductive film type fixed resistor and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-inductive film type fixed resistor which can hold high resistance value precision while restraining residual inductance to a minimum, and has a resistance value of high precision and high non-inductive property, and to provide a manufacturing method of the resistor. SOLUTION: A part of a resistance film formed uniformly on the surface of a rod type insulator is cut into a C-shaped ring type having an aperture part in a part of a circular form, or a ring type in which the C-shaped ring is inclined spirally, or a cutting pattern set in longitudinal type combination which is in parallel or inclined to an axial line, and a thin belt of a resistance coating film is formed. In order to obtain an aimed resistance value with high precision while ensuring high non-inductive property, cutting is performed by calculating the length of cut and its direction in the final stage on the basis of data in the course of working for forming the thin belt of a resistance film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbon film type, a metal film type, and a metal glaze type non-inductive film type fixed shaft in the telecommunications field. The present invention relates to a non-inductive coating type fixed shaft with high non-inductivity and a method for manufacturing the same.

[0002]

2. Description of the Related Art Fixed resistors include wire wound type, carbon film type,
A metal film type, a solid type, a chip type and the like have been put to practical use. Commonly used fixed shafts have a residual inductance in addition to the pure resistance component. In electrical and electronic equipment, fixed earthen fittings are used in a frequency range where the influence of the inductance is small, or are used after taking measures to prevent the inductance from having a bad influence. Therefore, a resistor having a small inductance is usually required in a field of a high-frequency device, a field of a device using a pulse, and a field of a device which easily generates a high surge voltage. On the other hand, as the application field of semiconductor parts has expanded in recent years,
Even if the fundamental frequency is relatively low, radiation and induction of AC harmonic components having steep waveforms will be a problem,
In electrical and electronic circuits, a reduction in the inductance of a resistor acting as an antenna for electromagnetic waves is required in part.

[0003] Originally, a conductor having a certain length and thickness has an inductance with respect to an alternating current. Therefore, there is no strictly non-inductive type resistor. If the inductance is sufficiently small, it is called a non-inductive resistor and is used. Therefore, in general, a solid type and a chip type, which do not form a coil-shaped electric path, are non-inductive types. Normally, a wire-wound shaft is molded into a coil, but even with a film-type resistor, the film is spirally cut to obtain a high resistance value, so the resistive film forms a coil and remains. This causes the inductance to increase. A commercially available non-inductive resistor is obtained by winding a resistance winding in a folded manner as shown in FIG. 11 or by shaping a resistance coating on an insulating flat plate in a zigzag manner as shown in FIG. ,
Applications are limited due to shape, resistance value, heat capacity and the like.

[0004]

SUMMARY OF THE INVENTION In order to easily realize non-induction of a generally used film type resistor, the inventor of the present invention first described "non-induction film type fixed resistor". And its manufacturing method ”(Japanese Patent Application No. 11-1).
44329, unpublished). The present invention is a further improvement and development of the present invention. That is, an object of the present invention is to maintain a high resistance value accuracy while minimizing the residual inductance, thereby making it possible to maintain a high accuracy resistance value and a high non-inductive property. And a method of manufacturing the same.

[0005]

According to the present invention, a part of a resistive film uniformly formed on the surface of a rod-shaped insulator is formed into a C-shaped ring having a circular opening. By cutting the C-shaped ring into a spirally inclined ring shape, or into a cutting pattern set in a vertical combination parallel or inclined to the axis, a thin band of the resistive film is formed, and In order to accurately obtain the target resistance value while maintaining high non-induction, the length and direction of the cut in the final stage are calculated based on data during processing to form a thin band of the resistive film. A method for producing a non-inductive coated fixed shaft is provided.

According to a preferred embodiment of the present invention, in a pattern in which the resistance coating formed by cutting has an even number of electrical paths, the resistance value at the end of the last previous ring cut is measured to cut the final ring. Optimum increase in resistance value for one ring in the cutting process. Symmetrical to the center line of the opening from the data, the same number and length of electric circuits required to obtain the desired resistance value. Calculate the cutting length and cut the shape to widen the opening.

Further, in a pattern in which the number of electric paths of the resistive film formed by cutting is odd, the first ring cut is postponed, cutting is started from the second cut, and the last one before the last ring cut is completed. Measure the resistance value and, if the last cutting pattern is the same as the second pattern, cut twice the number of electrical circuits with the same length necessary to obtain the desired resistance value Find the length by calculation, cut the first ring and the final ring in the same direction and expand the opening to the same length,
If the last cutting pattern is different from the second pattern, add one ring cut at the position of the final ring, measure the resistance value, and calculate the desired resistance value. The cutting length of twice the number of electrical circuits with the same length required for the calculation is calculated, and the first ring and the final ring are cut in the same direction in such a manner that the opening is widened to the same length.

Further, the relationship between the cutting length and the increase in the resistance value is measured and recorded, and the folded portion or cut opening of the electric path of the resistive film to be formed and the portion where the electric path of the resistive film have the same width are formed. It is preferable that the calculation is performed after being decomposed into

Further, according to the present invention, a part of the resistive film uniformly formed on the surface of the rod-shaped insulator is formed into a C-shaped ring shape having an opening in a circular part, or a C-shaped ring is formed. It is formed into a spirally inclined ring shape, and further cut into a cutting pattern that is set by combining a vertical cut parallel or inclined to the axis, thereby forming a thin band of a resistance coating, and In order to accurately obtain the desired resistance value while maintaining high non-induction, determine the cutting order and adjust the length of the specific vertical cut to match the resistance value in the final cut. A method for manufacturing a non-inductive coated fixed shaft is provided.

According to a preferred embodiment of the present invention, in a pattern in which the number of electric paths of the resistive film formed by the vertical cutting is an even number, two adjacent to the vertical cut located at the center of the opening of the ring cut. After finishing the vertical cut, and after finishing all other vertical cuts, measure the resistance value and calculate the cutting length of the two later vertical cuts required to obtain the specified resistance value And cut in the same direction with the same length.

In a pattern in which the number of electric paths of the resistive film formed by the vertical cutting is an odd number, a vertical cut connecting a pair of openings of two ring cuts at both ends of the resistor main body. After the vertical cut adjacent to one side is postponed and all other vertical cuts are completed, cutting of the postponed vertical cut is performed while measuring with a resistance meter until a predetermined resistance value is reached.

Further, according to the present invention, in a non-inductive coating type fixed mortar having a cutting pattern mainly composed of a vertical cut, an optimum cutting order is selected and cutting is performed while measuring a resistance value. Accordingly, there is provided a method for manufacturing a non-inductive coating type fixed shaft, wherein a desired resistance value is accurately obtained while maintaining high non-inductivity.

[0013] According to the above-described non-inductive coating type fixed hull of the present invention and the method of manufacturing the same, the resistance coating formed on the surface of the insulating material or the rod-shaped insulator whose surface is insulated is cut into a unique cutting pattern. By processing, it is possible to obtain a non-inductive coating type fixed shaft having excellent high frequency characteristics and pulse resistance characteristics. That is, as described later, by the cutting according to the above-described method, the magnetic field generated by the flow of the current is configured to cancel the current flowing in the adjacent electric circuit in the reverse direction, and the branch point of the even-number electric circuit. At the confluence point, by configuring the currents to be the same and opposite in direction, it is possible to cancel as many magnetic fields generated by the flow of the current as possible. That is, the vector sum of the magnetic field generated by the current can be minimized, and the residual inductance can be greatly reduced.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, any of metal-coated pits, carbon-coated pits, and metal-glazed pits is used for forming a coating in the manufacturing process to which the present invention is applied. Since the cutting process is the same, the description will be made in a manner that includes these in the name of the coating type pit. In the case of a film-type pit, a strong carbon coating or metal coating is generally formed on the surface of an insulator such as a porcelain round bar, and then this resistance coating is cut spirally until the surface of the porcelain appears. We are making a shaft with the desired resistance. For this reason, since the current path is formed in a coil shape, the current path has an inductance with respect to alternating current as in the case of a general winding type.

The general structure of a film type resistor will be described with reference to FIG. 1 means a resistor. Reference numeral 2 denotes a round bar made of porcelain, on the surface of which a strong resistive film 3 is formed. Reference numeral 4 denotes a groove formed by cutting the resistance coating 3 up to the surface of the round bar 2 made of porcelain. Reference numeral 5 denotes a conductor cap for connecting the resistance film 3 and the lead wire 6.

A general method of processing a resistive film of a film type resistor will be described with reference to FIG. Reference numeral 7 denotes a thin disk-shaped cutter. At the time of cutting, the resistor 1 slowly rotates at a constant rotational speed in the direction of the arrow,
It is fed at a constant speed in the axial direction of the resistor. The disk-shaped cutter 7 rotates at high speed in the direction of the arrow. In the cutting process, the resistive film is cut off spirally by bringing the edge of the cutter 7 into contact with the resistor 1.
The pitch and length of the cutting are set after calculation in advance from the resistance value specific to the resistor and the required resistance value, and processing is performed automatically. An apparatus that performs processing by scattering a resistive film with laser light instead of a rotating disk-shaped cutter has also been generalized.

The basic principle of the non-inductive film resistor is as follows. (1) The electric path of the resistor formed by cutting is not a unidirectionally wound coil but has a turning point, and the current flowing through the electric path of the adjacent resistor is the same and the direction is opposite. . (2) Further, a plurality of electric circuits of the resistor are configured so that the magnitude of the current flowing separately from the branch point of the current and the magnitude of the current merging at the merging point of the current are the same but opposite in direction. (3) That is, the magnetic field generated by the flow of the current is configured to cancel each other by making the current flowing in the adjacent electric circuit reverse, and the magnitude of the electric current is determined at the branch points and the merging points of the even-number electric circuits. Are arranged in the same direction but in opposite directions so as to cancel out as much as possible the magnetic field generated by the flow of current. (4) That is, the vector sum of the magnetic field generated by the current is minimized.

FIG. 1 and FIG. 2 are diagrams showing a first embodiment of the present invention. FIGS. 1A to 1C show a configuration in which the magnitudes of currents flowing through the electric paths of adjacent resistors are the same and the directions are opposite to each other. An example of a resistor that is configured so that the current flowing separately from the branch point and the magnitude of the current that merges at the junction of the currents are the same but in opposite directions. The right figure in FIG. 1 (C) is a development view thereof, and the dotted line shows the state of the back surface slightly. A C-shaped cut is formed on the resistor uniformly formed on the surface of the insulating cylinder, and an opening of the C-shaped cut is formed by one.
C-shaped cuts of the same shape shifted by 80 degrees are arranged at equal intervals.

Assuming that a current flows from the left side of the resistor in FIG. 1A (the current flows in one direction even in the case of an alternating current, so that it is described as a direct current for the sake of convenience). Through the opening, and is divided into two first electric paths, each flowing in the opposite direction. When the current reaches the opening of the second C-shaped cut, it merges there, is divided into two by the second C-shaped cut through the opening, and flows in opposite directions. It may be considered that the current returns. Thereafter, similar division and merging are repeated to merge at the final C-shaped opening and flow out to the right. Since the width between the two C-cuts is constant, the distance between the openings is also constant, and the thickness of the resistive film is considered to be almost constant, the resistance value between the openings of the two C-cuts is constant. And look good. Looking at the current of each adjacent circuit, the magnitude is the same and the direction is opposite, the current flowing separately from the branch point and the magnitude of the current joining at the junction of the current are the same and the direction is opposite, so the current The magnetic field generated by the flow of the current flows in opposite directions and cancel each other, so that the residual inductance is reduced.

Here, a problem in maintaining the resistance value accuracy of the non-inductive coating type fixed shaft of FIG. 1 will be described. Before starting the cutting, the base material of the shaft has some variation in the resistance value. In the conventional helical cut pit,
Since there is only one electrical path in the pit, the resistance rises linearly in the cutting process, so cutting is performed while measuring the resistance, and when the resistance reaches the specified resistance, cutting is stopped. Accuracy can be maintained. However, in the case of the non-inductive coating type fixed hull shown in FIG. 1, complicated calculations and high precision processing are required to complete all the ring cuts in the same shape. Without doing this complicated calculation,
As in the conventional helical-cut pit cutting, one-way cutting is performed while measuring the resistance value, and cutting is stopped when the specified resistance value is reached. The length of the cut in both directions from the center of the opening tends to be different, and if the difference occurs, the balance is lost and the residual inductance increases. The magnitude of the imbalance is about one half of the maximum ring cut length of the electric circuit, that is, about half a coil having the same diameter as the outer diameter of the resistor body. Since the current flowing through the electric circuit formed by the final cut shunts in inverse proportion to the resistance value of the formed electric circuit, there is no large difference in the length of the cut x the current value, but there is no difference from the electric circuit before the last one. Loss of balance.

For a two-pattern, non-guided, fixed-type gallery, shown in FIG. 1, the final C-cut is centered at the opening of the immediately preceding C-cut. On the other hand, if the lengths are the same in opposite directions, and the resistance value is made to coincide with the target value, both non-inductivity and accuracy of the resistance value can be achieved.

FIG. 2 is a characteristic diagram in FIG. Hereinafter, a method of calculating the length of the final cut in the first embodiment of FIG. 1 will be described with reference to FIG. In FIG. 2, the horizontal axis represents the expected angle from the cylinder axis of the circumference where the cutting of the cylindrical pit body is performed. The vertical axis represents the resistance value that increases with the progress of the ring cut. Ro is an increase in resistance value due to one ring cut. The lower diagram (B) of FIG. 2 shows the pattern of the C-shaped ring cut shifted by 180 degrees. C1 represents the last two previous cuts, C2 represents the last one previous cut, and C3 represents the last cut.

When the second and subsequent C-shaped ring cuts are started from the end (S mark) of the C-shaped opening, the resistance value hardly increases in the first half of the circumference, and the C-shaped ring of the last cut is cut. When it comes to the front of the opening (mark E), it gradually increases, and when it passes the front of the opening of the C-shaped ring of the previous cut (mark S), it rapidly increases. ) One ring cut is completed. The description will be made on the assumption that the resistance value that rises in one ring cut hardly changes between rings, but is calculated using the data of the immediately preceding cut as the data closest to the final cut.

The upper part (A) of FIG. 2 shows how the cutting angle and the resistance value of the last two rings and the last one ring are increased in comparison with the respective ring cut angles. The reason why the resistance value increases only slightly (Ra) in the first half circumference in the cut C2 of the last immediately preceding ring is that the opening of the last two preceding rings is opened in the unprocessed direction of the resistance coating. It is. The resistance value gradually increases (up to Rb) when cutting progresses to the front of the opening of the last two previous rings because the opening state of the opening is restricted. After passing through the opening of the last two previous rings, the resistance value rises rapidly and the resistance value of one ring cut (R
The reason why the upwardly rising curve is drawn up to the point o) is that the resistance formed in the first half circumference affects the resistance formed in the second half circumference in parallel.

Here, it is assumed that the cutting of the final ring is started from before the center position of the opening (estimated angle ko) of the ring immediately before the final ring, and is simultaneously cut to the opposite side at a constant speed. The resistance value gradually rises up to the resistance value increase (Rb-Ra) only in front of the opening before passing through the opening of the last previous ring, and when passing, the resistance value of one ring cut linearly Min (Ro). The resistance value (Rx) to be increased in the final cut is a value obtained by subtracting the resistance value obtained from the target resistance value to the last previous ring cut. Proportional calculation can be performed using the ascending characteristics. That is, from before the center position of the opening of the ring immediately before the last,
If the final cuts of the same length (expected angle Kx) are made in the opposite directions in the form of widening the openings, a target resistance value can be obtained while maintaining a high non-inductive property. The manner in which the resistance value is increased by the final cut is shown at the top of FIG.

The contents described above can be expressed by the following equation.
become that way.

[0027]

(Equation 1)

In the formula 1, Ra: the amount of increase in resistance value when the ring cut before the last one reaches the opening of the cut before the last two, Rb: the ring cut before the last one before the last two Resistance increase when passing through the opening of the cut
o: increase in resistance value at the end of the last previous ring cut, Rx: resistance value to be increased in final cut, Ko:
The angle of the opening, Kx: the sorting angle of the final cut.

When the first equation is rewritten as a calculation equation for obtaining Kx, the following equation 2 is obtained.

[0030]

(Equation 2)

As described above, for the pattern of the non-inductive coating type fixed hull shown in FIG. 1, the final C-shaped cut is made with respect to the center of the opening of the immediately preceding C-shaped cut. In the opposite direction, the length is the same, and the resistance value is made to coincide with the target value. In other words, if the expected angle Rx is cut, the non-induction and the accuracy of the resistance value can be easily compatible. Can be. Figure 1 shows the appearance of the final cut resistor
FIG. 1B shows a front view and a developed view in FIG. In this figure, a portion indicated by an arrow A is a portion where the length of the final cut is adjusted.

FIGS. 3 and 4 are views showing a second embodiment of the present invention. FIG. 3 shows that at least one vertical cut parallel to the axis of the resistor body corresponding to the number of electric circuits and a cut parallel to the axis as a starting point are shifted into a spiral shape having an opening partly. C
An example of a non-inductive coating type fixed pit having an even number (two) of electric paths constituted by die cutting is shown. In this type of pit, there is a turning point of the electric circuit, and the current flowing through the electric circuit of the adjacent resistor is the same and the direction is opposite,
The branch points and junctions of the plurality of electric paths are limited to points at which the potentials generated by the current flowing into and out of the adjacent openings become equal to the current inflow / outflow portions at both ends of the resistor. Even for the non-inductive coating type fixed shaft of this pattern, the C type cut shifted to the final spiral shape is shifted to the last spiral shape immediately before the branch point or the junction of the electric circuit. When the length is the same in the opposite direction to the center of the opening of the die cut and the resistance value is made to coincide with the target value, both non-inductivity and accuracy of the resistance value can be achieved.

Hereinafter, a method of calculating the length of the final cut will be described with reference to FIG. The manner in which the resistance increases during the cutting process of this pattern of non-inductive coated fixed shafts takes two different forms. One is the same as the state of the increase in the resistance value (FIG. 2) in the cutting process of the non-inductive coated fixed shaft of the pattern of FIG.
The other one is very different. The difference is that the former is the case where the previous cutting pattern has a branch / junction of the electric circuit at the center of the cutting, and the latter is that the previous cutting pattern has the turning point of the electric circuit at both ends. It is a case where it has. In FIG. 4B, I indicates a vertical cut at a position of 0 °.

FIG. 4 shows how the resistance value increases in both cutting processes. As is apparent from the figure, the state of the increase in the resistance value in the latter cutting process shows a sharp increase in the resistance value in a narrow range of the cutting angle, and is therefore difficult to use as calculation data. On the other hand, the state of the increase in the resistance value in the former cutting process can be handled in the same manner as described in the first embodiment, and this is used as calculation data. When the C-shaped cut shifted to the last spiral pattern is the former pattern, the data is used. When the C-cut is the latter pattern, the data is shifted to the last two spiral patterns. The C-shaped cut should be the former pattern.
Use a tar.

The detailed description is the same as that of the first embodiment, and will not be repeated. The calculated cutting angle is applied in a manner that widens the opening of the pattern of the final cut.
FIG. 3B shows the appearance of the final cut resistor, and FIG. 3C shows a front view and a developed view. In this figure, a portion indicated by an arrow A is a portion where the length of the final cut is adjusted.

FIGS. 5 and 6 are views showing a third embodiment of the present invention. FIG. 5 shows an example of a resistor having a turning point, configured so that currents flowing through the electric paths of adjacent resistors have the same magnitude and opposite directions, and an odd number (one) of electric paths of the resistors. Show. A C-shaped cut and a C-shaped cut of the same shape shifted by an angle of an opening of the C-shaped cut are arranged at equal intervals on a resistor uniformly formed on the surface of the insulating cylinder. Further, all C-shaped cuts are cut off by straight cuts parallel to the axis of the resistor body connecting one end of the opening. Now, if current flows from the left side of the resistor,
It passes through the opening of the first C-shaped cut and flows into the first electric circuit formed by the first and second C-shaped cuts. The current strikes the straight cut and flows through the opening of the second C-cut into the second circuit created by the second and third C-cuts. In the same manner, it passes through the third electric circuit, the fourth electric circuit, and so on, and flows out to the right from the final C-shaped opening.

Looking at the currents of the adjacent electric circuits, since the magnitudes are equal and the directions are opposite, the magnetic fields generated by the flow of the currents are in opposite directions and cancel each other, so that the residual inductance is reduced. In FIG. 5, all the C-shaped cuts have the same length, and the first C-shaped cut and the final cut have the same length in the same direction. To get an accurate resistance value,
Requires complicated calculations and high-precision machining. Instead of performing this complicated calculation, in the method of cutting in one direction while measuring the resistance value and cutting off when the resistance value reaches the specified value, as in the cutting of a conventional helical cut pit, the final ring Then, a difference is easily generated in the length from the first ring, and if the difference occurs, the balance is lost and the residual inductance increases. The magnitude of the unbalance corresponds to about one maximum ring cut.

As shown in FIG. 5 (B), for the pattern of the non-inductive coating type fixed earthen fitting shown in FIG. 5, the first C-shaped cut and the final C-shaped cut are made with respect to the opening. If the resistance is equal to the target value in the same direction and the same length, the non-inductive property and the accuracy of the resistance value can be compatible. In this method, the first C-cut is postponed, so that the first C-cut is postponed, and the second C-cut is started, and the cutting angle calculated by the last stage of cutting is calculated. After finishing the final C-shaped cut, return to the position of the first C-shaped cut and
The cut will be made in the same direction at the same angle as the mold cut.

The problem here is that it is necessary to make the first cutting pattern and the last cutting pattern the same pattern, reverse the direction of the inflow current and the outflow current, and balance the entire resistor. That is. Therefore, the resistance value at the end of the last C-type cutting is measured, and at the same time, the last C-type cutting pattern is compared with the second C-type cutting pattern.
The cutting angle required to increase by half the value obtained by subtracting the resistance value at the end of the last C-type cut from the predetermined resistance value is calculated, and the final cut and the first cut are performed. The last C-type cutting pattern is compared with the second C-type cutting pattern, and if they are not the same, one cut is added to the position of the last cut (the first C-type cutting pattern). Is delayed, so there is room for additional resistance)), measure the resistance again, and then increase the cutting angle required to increase by one-half the value obtained by subtracting the resistance from the predetermined resistance. Calculate and do the final cut and the first cut.

Hereinafter, a method of calculating the length of the final cut will be described with reference to FIG. In FIG. 6, the horizontal axis represents the expected angle of the circumference at which the column-shaped pit body is cut. The vertical axis represents a resistance value that increases with the progress of one C-shaped cut. FIG. 6B shows a C-shaped ring cut pattern in which the opening of the ring cut is shifted by an angle. C1 represents the last two previous cuts, C2 represents the last one previous cut, and C3 represents the last cut. At the bottom, # 1 indicates the position of the first cut, and # 2 indicates the second cut. I indicates a vertical cut at a position of 0 °. The upper part (A) of FIG. 6 shows the cutting angles of the last two rings and the last one before the ring and how the resistance value increases in comparison with the respective ring cut angles. As can be seen from this figure, the resistance value in the latter cutting process is gradually increased with respect to the cutting angle in the same manner as in the pattern of FIG. 4 and rapidly increased in a narrow range of the cutting angle. Because there is something that indicates
The former data is used as calculation data. Since this method can be handled in the same manner as described in the first embodiment, detailed description will be omitted.

The calculation of the angle of the final cut is as described above.
Since the adjustment of the resistance value to be increased is divided into two in both the first cut and the last cut, one half of the resistance value to be increased is used for calculating the angle of the final cut. FIG. 6 shows a method of obtaining the final and initial cut angles Kx based on cutting data that gradually rises with respect to the cutting angle, and a state in which the cut angles Kx are applied to the final and initial cuts. Show. After the final cutting is performed at the cut angle Kx, the cutting is returned to the initial cutting position and cut in the same direction at the same cut angle. The detailed description of the calculation is similar to that of the first embodiment, and will not be repeated. FIG. 5B shows the appearance of the final cut resistor, and FIG. 5C shows a front view and a development view. In this figure, a portion indicated by an arrow A is a portion in which the lengths of the last and first cuts are adjusted.

FIG. 7 is a diagram showing a fourth embodiment of the present invention.
In the non-inductive coating type fixed hull of the pattern shown in this figure, the turning point of the electric path of the non-inductive coating type fixed hull of the pattern shown in FIG. 5 is parallel to the axis of the resistor body. It is displaced at the part of the straight line cut, and is formed by the helical cut.
The C-shaped cut shifted to the first helical shape and the C-shaped cut shifted to the final helical shape have the same length in the same direction with respect to the opening, and the resistance value matches the target value. This makes it possible to achieve both non-induction and precision of the resistance value. The processing method for achieving both the non-inductive property and the accuracy of the resistance value of this pattern of the non-inductive coating type fixed shaft is omitted because it is the same as the method described in the third embodiment. FIG. 7B shows the appearance of the final cut resistor which also serves as resistance adjustment, and FIG. 7C shows a front view and a development view.

FIGS. 8 and 9 show a fifth embodiment of the present invention. The cutting pattern shown in FIG. 8 includes two ring-shaped C-shaped rings or C-shaped ring-cuts at both ends of the surface of the insulator round bar, and an even number parallel or slightly inclined to the axis of the insulator round bar. Even number with two vertical cuts (2)
An example of a non-inductive film type resistor having an electric circuit of FIG. The resistor of this pattern has a turning point of the electric circuit, and the current flowing through the electric circuit of the adjacent resistor is the same and the directions are opposite except for the opening. Further, since the two electric paths are symmetrical with respect to the vertical cut located at the center of the opening of the C-shaped cut, if the resistance values of the two electric paths are the same, the currents flowing through the electric paths are equal. Therefore, the residual inductance is reduced. Now, assuming that the current flows in from the left, the first cut formed symmetrically with respect to this vertical cut is a vertical cut that passes through the opening of the C-cut and is located at the center of the C-cut. It divides into two electric lines and flows. The current collides with the C-shaped cut, which is shifted by 180 degrees from the C-shaped cut, and reverses the direction to flow into the second electric circuit. Similarly, the third, fourth,. . . Finally, the two divided currents merge at the opening of the C-shaped cut and flow out to the right.

Looking at the currents of the adjacent electric circuits, the magnitudes are equal and the directions are opposite, so that the magnetic fields generated by the current flowing in the opposite directions cancel each other out, so that the residual inductance is reduced. In FIG. 8, all vertical cuts have the same length, but complicated calculations and high-precision machining are required to obtain high-precision resistance values while maintaining non-inductive properties in this manner. And Without this complicated calculation, like cutting a conventional helical cut resistor,
In a method in which cutting is performed while measuring the resistance value, and the cutting is stopped when the resistance value reaches a predetermined resistance value, the resistance values of the two electric paths are hardly equal to each other, so that the balance is lost and the residual inductance increases.

In the non-inductive film type resistor having the pattern shown in FIG. 8, the vertical position at the center of one C-shaped cut opening is obtained so that a desired resistance value can be obtained with high accuracy while maintaining high non-inductivity. The cutting process of the two vertical cuts on both sides of the die cut is postponed, all other vertical cuts are completed, and the length of the two cuts that were postponed is measured by the cutting process. By calculating from the same length and cutting in the same direction in the same length,
It is possible to achieve both non-inductivity and resistance value accuracy. For this reason, at the end of the cutting process, at the same time as measuring the resistance increase characteristics of one vertical cutting before the vertical cutting with post-cutting, the two cuts with post-cutting are left. Then, the resistance value in a state in which all other vertical cuts are completed is measured, and the difference between the value and a predetermined resistance value is used to determine the cut length of the two later cut-offs in the same manner as in FIG. Find and cut in the same direction.

Hereinafter, a method of calculating the length of the final cut will be described with reference to FIG. In FIG. 9, the horizontal axis represents a range Lcc in which a vertical cut is made between C-cuts.
Is shown. The vertical axis represents the resistance value that increases as the cutting progresses. In the lower diagram (B) of FIG. 9, the vertical cut is performed in such a manner that one end thereof is in contact with the C-shaped cut, and the other end is maintained at a constant interval from the C-shaped cut. One end is in contact with the C-shaped cut, and the other end is formed in such a manner that the C-shaped cut is kept at a fixed interval, and this state is repeated alternately. Assuming that the vertical cut located at the center of the C-shaped cut is the cut of the electric circuit, # 1 indicates the first cut position, # 2 indicates the second cut position above the lower diagram (B), and the lower portion of the lower diagram (B) To C1 is the last two previous cuts, C2 is the last one previous cut, and C3 and # 1 are the two adjacent cuts on both sides of the vertical cut located at the center of the opening of the C-shaped cut that was put on the back. Shows a vertical cut. Co indicates a C-shaped opening.

The upper part (A) of FIG. 9 shows the length of the vertical cuts before the last two and the last one and the state of the increase of the resistance value in comparison with the length of each vertical cut. . As is apparent from this figure, the resistance value in the latter cutting process is increased gradually with respect to the cutting length as in the pattern of FIG. 6 and sharply increased in a narrow range of the cutting length. The former data is used as the calculation data because there is a data indicating an increase in the former. Since this method can be handled in the same manner as described in the first embodiment, detailed description will be omitted.

The calculation of the angle of the final cut is as described above.
Since the adjustment of the resistance value to be increased is divided into two by the two vertical cuts on both sides of the vertical cut located at the center of the opening of the C-shaped cut, half of the resistance value to be increased is finally cut. Used to calculate the length of FIG. 9 shows a method for obtaining the last and first cut lengths Lx based on cutting data that gradually rises with respect to the cutting angle, and the cut length Lx is applied to the final and first cuts. Show the situation. Cutting cuts the final cut length K
After performing x, return to the initial cutting position and cut in the same direction with the same cut length. The detailed description of the calculation is similar to that of the first embodiment, and will not be repeated. FIG. 8B shows the appearance of the final cut resistor, and FIG. 8C shows a front view and a development view. In this figure, a portion indicated by an arrow A is a portion in which the lengths of the last and first cuts are adjusted. In this cutting pattern, a vertical cut located at the center of the C-shaped cut is not necessarily required, but it is significant in that the electric circuit width is made as constant as possible and the heat generation per unit area is made as uniform as possible.

FIG. 10 is a view showing a sixth embodiment of the present invention. FIG. 9 shows a non-inductive coating in which a cutting pattern has two C-shaped ring-shaped cuts at both ends of a surface of an insulating round bar and a vertical cut parallel to the axis of the insulating round bar. An example of a mold fixed shaft is shown. In this pattern, there is a turning point of the electric circuit, and the current flowing through the electric circuit of the adjacent resistor has the same magnitude but the opposite direction. In the non-inductive coating type fixed hull of this pattern, it is formed by vertical cutting in a method of optimizing the order of cutting so that a desired resistance value can be accurately obtained while maintaining high non-inductivity. Two Cs at both ends of the resistive coating
Perform a vertical cut connecting the ends of the opening of the mold cut first, and after finishing all other vertical cuts sequentially, perform the last one cut while measuring the resistance value,
The cutting is ended when the resistance value reaches a predetermined value.
Figure 1 shows the appearance of the final cut resistor that also serves as resistance adjustment
FIG. 10 (C) shows a front view and a developed view at 0 (B).

Further, the cutting pattern has two C-shaped ring-shaped cuts at both ends of the surface of the insulator round bar and an electric circuit having a vertical cut slightly inclined from a line parallel to the axis of the insulator round bar. The resistance value of the induction coating type fixed shaft can be adjusted in the same manner as in the first to third embodiments.

In the above description, two lines are used for an even number of electric circuits,
The odd number of electric circuits has been described by using an example of one electric circuit. From the viewpoint of the application of the actual resistance value, the possibility of using a circuit having as many as three to four electric lines is extremely low. Also in these examples, it is possible to calculate and obtain the length (angle) of the final cut from the data of the cutting process, but the calculation becomes complicated and requires the help of a computer. For this reason, a pattern with a large number of electric paths will not be described, but the point of performing well-balanced cutting by calculation is common.

Although the above description has been made on the assumption that the cutting is always performed in the same state, in actuality, there are effects due to the thickness of the resistor coating, the shape of the cutter edge, the cutting depth, and the like. Modification at the processing site,
Amendments should be actively adopted.

The great advantage of the above method in holding the resistance value is that the resistance value is accurately measured at the final stage of cutting to determine the length (angle) of the final cutting. Since the error can be regarded as sufficiently small (measurement error only), the influence of the error in the final cut on the entire error can be reduced.

Although it has been described that the final cut is performed with the same electric circuit width as the other cuts, it is permissible to slightly increase the electric circuit width and increase the cutting length in order to increase the resistance value accuracy of the final cut.

Although the above-described processing method has been described using an insulating round bar as an example, a non-inductive film type resistor can also be manufactured using a cylindrical, prismatic, rectangular tube, or plate-like insulator. Is included in the present invention. Also, this application shows a basic idea. It is understood that methods which can be easily inferred from the contents of the present application are also included in the scope of the present invention.

[0056]

The non-inductive film type resistor manufactured by the above-described manufacturing method of the present invention satisfies the following conditions. (1) The electric path of the resistor formed by cutting is not a unidirectionally wound coil but has a turning point, and the current flowing through the electric path of the adjacent resistor is the same and the direction is opposite. (2) The current flowing separately from the branch point of the current and the currents merging at the current merging point are the same but opposite in direction with a plurality of electric paths of the resistor. (3) The magnetic field generated by the flow of the current is canceled by making the current flowing in the adjacent electric circuit in the opposite direction. Further, at the branch points and the junctions of the even-numbered electric circuits, the current is the same and the directions are opposite. Therefore, the magnetic fields generated by the flow of the current cancel each other. (4) The vector sum of the magnetic field generated by the current is minimized.

In other words, the non-inductive coating type fixed pit according to the manufacturing method of the present invention is configured so that the magnetic field generated by the flow of the current is canceled by making the current flowing in the adjacent electric circuit in the opposite direction. In addition, at the branch points and the merging points of the even-numbered electric circuits, the currents are configured to have the same magnitude and opposite directions, that is, the vector sum of the magnetic field generated by the current can be minimized, and the current flows. The resulting magnetic field can be canceled as much as possible. Therefore, the non-inductive coating type fixed earthenware of the present invention and the manufacturing method thereof can maintain high resistance value accuracy while minimizing residual inductance, and achieve high accuracy resistance value and high non-inductive property. It has excellent effects such as combining.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a characteristic diagram in FIG.

FIG. 3 is a diagram of a second embodiment of the present invention.

FIG. 4 is a characteristic diagram in FIG. 3;

FIG. 5 is a diagram of a third embodiment of the present invention.

FIG. 6 is a characteristic diagram in FIG. 5;

FIG. 7 is a view of a fourth embodiment of the present invention.

FIG. 8 is a view of a fifth embodiment of the present invention.

FIG. 9 is a characteristic diagram in FIG. 8;

FIG. 10 is a view of a sixth embodiment of the present invention.

FIG. 11 is a configuration diagram of a conventional inverted spiral cut type film resistor.

FIG. 12 is a configuration diagram of a conventional flat film type resistor.

FIG. 13 is a configuration diagram of a conventional film-type resistor.

FIG. 14 is a view showing a general method of processing a resistive film of a conventional film-type resistor.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 resistor 2 porcelain round bar 3 resistive coating 4 groove 5 cap 6 lead wire 7 cutter

Claims (9)

[Claims] 1. A ring in which a part of a resistive film uniformly formed on the surface of a rod-shaped insulator is formed into a C-shaped ring having an opening in a circular part, or a C-shaped ring is spirally inclined. Like
Alternatively, by cutting into a cutting pattern set in a vertical combination parallel or inclined to the axis, a narrow band of the resistive film is formed, and the desired resistance is maintained while maintaining high non-induction. Non-inductive coating type fixing, in which the length and direction of the cut in the final stage are calculated and cut based on the data during processing to form a thin band of the resistive coating so that the values can be obtained accurately. The method of manufacturing the shaft. 2. In a pattern in which the number of electric paths of a resistive film formed by cutting is an even number, the resistance value at the end of the last previous ring cut is measured, and the final ring is cut by an optimal one ring in the cutting process. The cutting length of the same number and the same length as the number of electrical paths required to obtain the desired resistance value is calculated symmetrically with respect to the center line of the opening from the increase data of the resistance value per minute. The method for manufacturing a non-inductive coating type fixed shaft according to claim 1, wherein the opening is widened and cut. 3. In a pattern in which the number of electric paths of the resistive film formed by cutting is an odd number, the first ring cut is postponed, cutting is started from the second cut, and the last one before the last ring cut is completed. Measure the resistance value and, if the last cutting pattern is the same as the second pattern, cut twice the number of electrical circuits with the same length necessary to obtain the desired resistance value Find the length by calculation, cut the first ring and the final ring in the same direction and widen the opening to the same length, and if the cutting pattern immediately before the final is different from the second pattern Cuts one additional ring cut at the position of the final ring, measures the resistance value, and cuts twice the number of electrical circuits with the same length necessary to obtain the desired resistance value length 2. The method of claim 1, wherein the first ring and the final ring are cut in the same direction so as to extend the opening to the same length. Method. 4. The relationship between the cutting length and the increase in the resistance value is measured and recorded, and the folded portion or cut opening of the electric path of the resistive film to be formed and the portion where the electric path of the resistive film have the same width are formed. The method according to any of claims 1 to 3, wherein the calculation is performed after being decomposed into: 5. A ring in which a part of a resistive film uniformly formed on the surface of a rod-shaped insulator is formed into a C-shaped ring having an opening in a circular part, or a C-shaped ring spirally inclined. Into a cutting pattern set by combining vertical cuts parallel or inclined to the axis, forming a thin band of resistive coating, and
The cutting order is determined so that the desired resistance value can be obtained with high accuracy while maintaining high non-induction, and the length of a specific vertical cut is adjusted to match the resistance value in the final cut. A method for manufacturing a non-inductive coated fixed shaft. 6. A pattern adjacent to a vertical cut located at the center of an opening of a ring cut in a pattern in which the resistance coating formed by vertical cutting has an even number of electric paths.
After finishing the vertical cut of one book and finishing all other vertical cuts, measure the resistance value and determine the cutting length of the two later vertical cuts required to obtain the predetermined resistance value. 6. The method for manufacturing a non-inductive coating type fixed shaft according to claim 5, wherein cutting is performed in the same direction at the same length, obtained by calculation. 7. In a pattern in which the number of electric paths of a resistive film formed by vertical cutting is an odd number, a vertical cut connecting a pair of openings of two ring cuts at both ends of a resistor main body. After the vertical cut adjacent to one side is postponed and all other vertical cuts are completed, the cutting of the postponed vertical cut is performed while measuring the resistance value until a predetermined resistance value is reached. The method for producing a non-inductive coated fixed shaft according to claim 5. 8. In a non-inductive coating fixed fixture having a cutting pattern mainly composed of a vertical cut, an optimal cutting sequence is selected, and cutting is performed while measuring a resistance value. A method for producing a non-inductive coating type fixed shaft, wherein a desired resistance value is accurately obtained while maintaining the resistance. 9. A non-inductive coating type fixed shaft produced by the method of claim 1. Description: