JPS5941282B2 - Resistance element, resistance element assembly and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chip-shaped resistive element, a resistive element assembly having a large number of divisible resistive elements, and a manufacturing method suitable for manufacturing these.

Chip-shaped resistance elements are small in size, can be bonded to a planar conductive pattern, meeting the demands for high-density packaging, and have a uniform external shape, making it easy to use automatic equipment and assembly when mounting on printed circuit boards, etc. It has excellent features such as being able to
With the trend toward higher density packaging, the amount used continues to increase.

1A and 1B show a conventional example of a chip-shaped resistance element, in which electrodes 2 and 3 are provided on both sides of the surface of a ceramic substrate 1 made of alumina porcelain, etc., and ruthenium oxide is used to bridge the electrodes 2 and 3. R
A resistor 4 made of uO2 or the like is provided, and end electrodes 5 and 6 which are electrically connected to the electrodes 2 and 3 are adhered to both sides of the ceramic substrate 1, and the surface of the resistor 4 is coated with glass or the like. Insulating by coating a protective layer 4a consisting of
The structure ensured oxidation resistance and chemical resistance.

The aforementioned end electrodes 5 and 6 serve as connection parts with the outside when the resistive element is mounted on a printed circuit board, etc., and silver paste or the like is applied with a brush over one end of the electrodes 2 and 3. It is formed by printing and baking.

However, as shown in FIG. 2, at both ends of the ceramic substrate 1, the surfaces 1a to 1e intersect at right angles, forming a right angle ridge angle P1.
.about.P8 are formed, so when the silver paste is applied with a brush, the coating thickness at the edge angles P1 to P8 tends to be thinner.

In order to compensate for this lack of coating thickness, silver paste is applied repeatedly with a brush to the edge angles P1 to P8 two to three times, but at this time, silver paste is also applied around edge angles P and -P8. , especially at both ends in the width W1 direction, the edge angle (Pl
:P57 P7 ), (P2.P5.P8), (P3
t P6 tP8), (P4 z Pa > P7)
As shown in FIG. 3, the thickness of the silver paste on both ends of the ceramic substrate 1 in the W1 direction is thicker than on the other sides, as shown in FIG.

The thickness tl of this type of chip-type resistance element is at most 1 m.
Since it is very thin, around m, even if the dimensional difference in the thickness of the silver paste coating is small, the ratio to the thickness tl becomes very large.

For this reason, when trying to store the chip-type resistive elements one after another in a cylindrical magazine of an automatic mounting machine, the edge angles P1 to
The error in the coating thickness of P8 becomes an obstacle, making it impossible to smoothly insert the resistance element into the cylindrical magazine, or increasing the apparent stacking thickness, reducing the amount that can be inserted into the automatic mounting machine. However, there was a drawback that the efficiency of assembly was reduced.

A similar problem also occurs when a required number of box-shaped magazines are arranged on a lattice-shaped guide plate and a required number of chip-shaped resistive elements are automatically mounted at predetermined positions on a printed circuit board at the same time.

Furthermore, they are unstable when stacked and tend to cause trouble during automatic insertion.

Furthermore, these chip-shaped resistance elements have been developed to be smaller, larger in capacity, and
In order to have the same dimensions as chip-shaped ceramic capacitors, which were developed in response to demands for high-density packaging, and share an automatic insertion machine, the finished dimensions are required to be extremely small, for example, around 3.2 x 1.6 x 0.6%. Due to the difficulty of handling and the need to form electrodes and resistors within a microscopic area of approximately 3.2 x 1.6%, it is extremely difficult to manufacture a single resistor element from the beginning to the end of the manufacturing process. It is difficult to

Therefore, the present invention eliminates the above-mentioned conventional drawbacks, and provides a chip-shaped resistance element that has a small stacking thickness and is convenient to insert into an automatic placement machine, and an easy-to-handle resistance element that can be easily indexed. It is an object of the present invention to provide an element assembly and a manufacturing method suitable for manufacturing the same.

In order to achieve the above object, the resistance element according to the present invention has end electrodes that are electrically conductively connected to the resistor at both ends in the length direction of a ceramic base coated with an electric resistor on at least one surface. In the resistor element, the ceramic substrate has a cutout portion at each of the four corners of the ceramic substrate, which narrows the width of the ceramic substrate toward the tip in the longitudinal direction. electrodes are formed in the plane of each portion, the resistor is applied so as to bridge the electrodes, and the end electrode is formed from above the electrode to the side end surface in the length direction of the ceramic base. It is characterized by having been given.

Further, the resistance element assembly according to the present invention has a resistance element in a region defined by linear grooves provided in a lattice shape on a ceramic substrate, and the longitudinal grooves and the horizontal grooves of the grooves are connected to each other. In a resistor element assembly having a through hole at an intersection portion, a conductive layer having a width smaller than the width of the through hole is coated on the ceramic substrate from above either the vertical groove or the horizontal groove of the recessed groove. The conductive layer is coated with a resistor so as to bridge the conductive layers.

Furthermore, the manufacturing method according to the present invention for manufacturing the resistance element and the resistance element assembly includes forming grooves in a lattice shape on the surface of the porcelain sheet, and forming through holes at the intersections of the vertical grooves and the horizontal grooves of the grooves. a step of depositing a conductive layer having a width smaller than the width of the through hole on the porcelain substrate from above either the vertical groove or the horizontal groove of the recessed groove, and a step of forming a conductive layer surrounded by the through hole. and depositing a resistor between the adjacent conductive layers in the region.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The content of the present invention will be specifically described below with reference to the accompanying drawings, which are examples.

4A and 4B are a plan view and a cross-sectional view of a chip-shaped resistance element according to the present invention.

In the figures, the same reference numerals as in FIGS. 1A and 1B indicate functionally identical components.

In this embodiment, arc-shaped missing portions 7, 8 are formed at the four corners of both ends of the porcelain substrate 1 formed into a flat plate, such as alumina porcelain. 9 and 10 are provided.

With such a structure, both ends in the width W1 direction, where the thickness of the silver paste tended to increase during brush painting, are cut off, and both ends of the end electrode 56 are cut off in the width W1 direction.
Since it is located inside the extension line L1°L2 of the two sides in the direction, even if an error in coating thickness occurs, it will become an obstacle when inserting the resistor element into the magazine of the automatic mounting machine. Never.

Therefore, the resistance element according to the present invention can be inserted into the magazine of an automatic mounting machine very smoothly and reliably in a predetermined number, and automatic mounting and assembly operations can be carried out efficiently.

The electrodes 2 and 3 are formed within the plane of the portion narrowed by the missing portions 7 to 10 on both ends of the ceramic base 1 in the length direction.

With such a structure, the maximum width of the electrodes 2 and 3 is smaller than the width W1 of the ceramic substrate 1, and when the resistive elements are arranged side by side in the width direction as shown in FIG. Since the end electrodes 5, 6 and the electrodes 2, 3 are not in contact with each other, it is possible to mount them on a circuit board in this arrangement, thereby improving the mounting density.

In addition, it is possible to carry out the trimming work of the resistor 4 for measuring the resistance value and adjusting the resistance value in the lined up state, so that the work of measuring and adjusting the resistance value is facilitated and the workability is improved.

In addition, since the electrodes 2 and 3 are formed on both longitudinal ends of one surface of the porcelain base 1, and the resistor 4 is attached so as to bridge these electrodes 2-3, the resistor 4, the position, width, etc. of the electrodes 2.degree. 3 can be set in advance with high precision by means such as screen printing.

Therefore, it is possible to set the volume of the resistor 4 between the electrodes 2 and 3 to a predetermined value, and to set the resistance value with high accuracy.

Furthermore, since the structure is such that the end electrodes 5 and 6 are provided from above the electrodes 2 and 3 to the side end surfaces in the length direction of the ceramic base 1, the end electrodes 5 and 6 are easily attached when mounted on a printed circuit board. It is possible to reliably solder the conductor pattern on the printed circuit board and improve the reliability of external connections.

Note that the missing portions 7 to 10 may be oblique or angular, and the resistor 4 may have another pattern that is easy to trim.

Next, a resistance element assembly according to the present invention will be explained.

FIG. 6 is a plan view of one embodiment, and FIG. 7 is an enlarged sectional view taken along line C2-02 in FIG.

In the figure, numeral 11 is a ceramic sheet that becomes the ceramic substrate 1 shown in FIGS. 4A and 4B, and is made of alumina porcelain or the like by firing and sintering.

On the surface of the porcelain sheet 11, linear grooves S1. S2 is carved in a grid pattern.

Either one of the grooves Sl and S2, for example, the vertical groove St
is provided with both ends extending to both edges of the porcelain sheet 11, and a conductive pattern 12 is formed on the vertical groove S1 by means such as silver paste printing and baking.

Also, each area Q divided by the vertical groove S1 and the horizontal groove S2
1 to Qn are resistors 13 made of ruthenium oxide or the like.
are formed so as to bridge the conductive battens 12.

Therefore, a resistance element made of the resistor 13 is formed in each region Ql-Qn.

Further, a through hole 14 passing through the porcelain sheet 11 in the thickness direction is provided at the intersection of the vertical groove S1 and the horizontal groove S2 of the concave groove.

The porcelain sheet 11 is a sintered body and is hard, and easily breaks along the grooves S, , S2.

However, the concave groove S1. If S2 is continuous at the intersection, for example, even if you try to fold it along the vertical groove S, the bending force will also be applied in the direction of the horizontal groove S2, and the -light position will bite in the direction of the horizontal groove S2 at the intersection. Therefore, it is difficult to fold accurately along the vertical groove S1.

However, when the through hole 14 as described above is provided, the groove S1. S2 becomes discontinuous, and the connection between the resistance elements at the intersection portion is cut off, so that the concave groove S1. S
It can be accurately folded and divided along two lines.

The width of the through hole 14 is larger than that of the conductor pattern 12, that is, the width of the conductor pattern 12 is larger than the width of the through hole 1.
Form it so that it is divided into 4 parts.

With such a structure, the groove S1. The resistance element shown in FIG. 4 can be obtained by simply dividing along S2 and providing end electrodes.

Moreover, since the resistive elements that are adjacent to each other in the vertical direction, which is the direction in which the conductive pattern 12 is formed, are electrically isolated from each other by the through holes 14, the resistance value of each resistive element can be measured in this assembled state. It becomes possible to perform trimming work of the resistor 13 for value adjustment.

Therefore, resistance value measurement and adjustment work becomes easier, and workability is improved.

Resistance elements adjacent in the horizontal direction share the conductor pattern 12 and are electrically connected to each other, but since they are connected in series, they do not affect the aforementioned resistance measurement and resistance adjustment work. .

In the embodiment, the corner of the through hole 144 is formed into a groove S.
1. Although the shape is square according to S2, it may be circular, oval, or other square shape.

Since the resistance element assembly according to the present invention has the above-described structure, as shown in FIG. 6, after applying force F1 to both sides of the groove S1 and dividing each row along the groove S1, As shown in FIG. 8a, end electrodes 5 and 6 are applied to both side surfaces by means such as brush painting, and as shown in FIG.
By folding and dividing along the groove S1. The resistance element divided by S2 can be taken out as a single unit.

The resistor elements taken out in this way are shown in Fig. 4A and B.
Similarly, the ceramic substrate 1 has a structure having missing parts 7 to 10 at the corners of both ends.

In this case, the porcelain sheet 11 is a hard sintered body, and the groove S1. Since the portion S2 is mechanically weak and has the through hole 14, each resistive element can be easily and accurately divided.

Furthermore, by simply adding the end electrodes 5 and 6, it can be assembled into a circuit board or the like immediately after being divided, which is convenient for use.

In addition, since the shape is many times larger than that of a resistive element alone, there is no fear of losing it, and it is convenient to handle and store.

Furthermore, as is clear from FIG. 8a, when indexed along the groove S1, each resistance element is electrically independent even though it is integrated through the porcelain sheet 11. , the resistance value of each resistor element can be measured in the state shown in FIG.

As a means for trimming the resistor 13, a diamond cutter, sandblasting, a laser beam, an ultrasonic cutter, or the like can be used.

Next, a method for manufacturing the above-described resistive element or resistive element assembly will be explained.

9a to 9d are process diagrams of the manufacturing method according to the present invention.

First, as shown in FIG. 9a, a rectangular porcelain sheet 11 is made from a porcelain sheet before firing by means such as punching.

This porcelain sheet 11 is made of alumina porcelain or the like as described above.

Next, as shown in FIG. 9, linear grooves S1. At the same time as providing S2 in a lattice shape, grooves s
t) At the intersection portion of 82, the corner portion is a concave groove S1. A rectangular through hole 14 is provided to match S2.

The grooves S, , S2 and the through hole 14 can be formed at the same time using a die or the like.

Moreover, the concave groove S1. At least one of the grooves S2, for example, the vertical groove S1, is provided so as to reach two opposing sides of the porcelain sheet 11.

Next, after firing and sintering this porcelain sheet 11, as shown in FIG. Further, as shown in FIG. 9d, a groove S1.
A resistor 13 is printed and formed in each region QI-Qn divided by S2 so as to bridge the conductive patterns 12.

Through the above steps, the resistor element assembly shown in FIG. 6 is obtained, but by printing and baking a glass layer on the conductive pattern 12 and the resistor 13, the conductive pattern 12, The resistor 13 and the glass layer are fixed to obtain a finished product.

FIGS. 10a and 10-a5 are diagrams explaining steps in other embodiments of the manufacturing method according to the present invention, and FIGS. 10b1-b5 are cutting lines X1-X1-X5-X in FIGS. 10 a1-a5.
5 are shown respectively.

First, as shown in FIGS. 10A and 10J, a band-shaped porcelain sheet 15 is formed from an alumina porcelain material or the like.

The porcelain sheet 15 is obtained by preparing a porcelain paste from a predetermined porcelain powder, an appropriate binder, and an appropriate amount of solvent, and forming the paste into a sheet by a doctor blade method, a screen process printing method, or the like.

Next, Figure 10 a2. As shown in b2, porcelain sheet 15
Holes 16 are bored at both ends in the width W2 direction along the length direction at regular intervals d1.

The porcelain sheet 15 is yet to be fired, and the holes 16 can be easily formed using a well-known punching device.

Next, Figure 10 a3. As shown in b3, porcelain sheet 15
Concave grooves consisting of vertical grooves S1 and horizontal grooves S2 are provided in a grid pattern on the surface of the substrate.

The grooves S] and S2 are easily positioned with reference to the hole 16.

That is, for example, a sprocket or the like having a pitch that matches the pitch of the hole 16 is engaged with the hole 16, the porcelain sheet 15 is fed by the sprocket, and the press die is driven once in synchronization with the amount of rotation of the sprocket. By this, the groove S1. This means that S2 is provided at a predetermined position with reference to the hole 16.

Next, Figure 10 25? As shown in b4, a through hole 14 is provided at the intersection of the vertical groove S1 and the horizontal groove S2.

The through hole 14 is also formed using a press die or the like, but the positions of the vertical groove S1, the horizontal groove S2, and their intersections are different from that of the hole 1.
6, the through hole 14 can also be easily positioned with reference to the hole 16.

Note that this through hole 14 can be formed at the same time as the grooves SI and S2, and is not limited to an ellipse, but may be a circular hole or a square hole.

Next, as shown in FIG. 10, b5, grooves S1. of the porcelain sheet 15 are formed. The portion in which S2 is formed is punched out into a rectangular shape to form a ceramic sheet 11 for a resistance element assembly.

Note that this punching process is performed using the groove S1. This can be performed simultaneously with the step of forming S2 and the through hole 14.

Next, through the steps explained in FIGS. 9c and 9d, the conductive pattern 12, the resistor 13, and the glass layer are printed and baked, and the resistor element assembly shown in FIG. 6 is completed.

As described above, the chip-shaped resistor element according to the present invention is a chip-shaped resistor having end electrodes electrically connected to the electrodes of the resistor at both ends of a ceramic substrate on which a resistor is attached. Since the element is characterized in that the ceramic substrate has cutout parts at the corners of both ends, it can be smoothly inserted into the magazine of the shoulder motion mounting machine, and the amount of insertion can be significantly reduced. A resistive element that can be increased can be realized.

Furthermore, since resistance values can be measured and resistance values can be adjusted by trimming when the devices are arranged side by side, measurement and adjustment work becomes easier.

Further, the resistance element assembly according to the present invention has a structure on a ceramic substrate.
A resistive element including a resistor and an electrode is provided in a region defined by linear grooves provided in a grid pattern, and a through hole is provided at the intersection of the horizontal groove and the vertical groove of the groove. Since the resistive element is characterized by having a hole, it is possible to accurately determine the resistive element described above without causing damage, and furthermore, it is possible to provide a resistive element assembly that is convenient for handling, storage, etc.

Furthermore, the manufacturing method according to the present invention includes a step of forming grooves in a lattice pattern on the surface of the porcelain sheet and providing through holes at the intersections of vertical grooves and horizontal grooves of the grooves; A resistor having a large number of chip-shaped resistor elements on the same substrate in a divisible state, since it includes a step of printing and forming a resistor and its electrodes in a portion corresponding to the area surrounded by the horizontal groove. An element assembly can be easily manufactured, and a single resistor element can be easily taken out at a high yield through this resistor element assembly.

[Brief explanation of drawings]

1A and 1B are a plan view and a sectional view of a conventional chip-shaped resistance element, FIGS. 2 and 3 are diagrams explaining the drawbacks thereof, and FIGS. 4A and 4B are diagrams of a chip-shaped resistance element according to the present invention. A plan view and a sectional view of the resistance element, FIG. 5 is a diagram for explaining the effect thereof, FIG. Figures 8a and 8b are diagrams for explaining the handling, Figures 9a to d are diagrams for explaining the steps in an embodiment of the manufacturing method according to the present invention, and Figure 10 is a diagram for explaining the handling.
Figures a1 to a5 are diagrams illustrating the steps in another embodiment, and Figures 10 b1 to b are Figures 10 a l to a5.
FIG. 1... Ceramic substrate, 2, 3... Electrode, 4
...Sheet resistor, 5, 6... End electrode, 7-10
... Missing part, 11 ... Porcelain sheet, 1
2... Conductive pattern, 13... Resistor, 14... Through hole, Sl. S2...Concave groove.

Claims (1)

[Scope of Claims] 1. A ceramic base coated with an electric resistor on at least one surface thereof has end electrodes electrically connected to the resistor at both ends in the length direction, and four corners of the both ends are provided. In a resistor element having a cutout portion that narrows the width of the ceramic base toward the tip in the length direction, in the plane of the portion narrowed by the cutout portion on both ends of the ceramic base in the length direction. Each electrode is formed, the resistor is attached so as to bridge the electrodes, and the end electrode is further provided from above the electrode to the side end surface in the length direction of the ceramic base. Resistance element. 2. A resistance element assembly having resistance elements in a region defined by linear grooves provided in a lattice shape on a porcelain substrate, and having through holes at intersections of vertical grooves and horizontal grooves of the grooves. In the body, a conductive layer having a width smaller than the width of the through hole is deposited on the ceramic substrate from above either the vertical groove or the horizontal groove of the concave groove, and a resistor is formed so as to bridge between the conductive layers. A resistor element assembly characterized by being coated with. 3. forming grooves in a grid pattern on the surface of the porcelain sheet and drilling through holes at the intersections of the vertical and horizontal grooves of the grooves;
a step of depositing a conductive layer having a width narrower than the width of the through hole onto the porcelain substrate from above either the vertical groove or the horizontal groove of the recessed groove; A method for manufacturing a resistive element or a resistive element assembly, comprising the step of depositing a resistor between the conductive layers.