JP2574684B2 - Substrate for brush assembly having integrated spring pedestal in frame and method of manufacturing brush assembly - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a brush assembly widely used as a potentiometer, a trimmer, an encoder, etc. for transmitting an electric signal in combination with a resistor, a slip ring, or the like. And a method for manufacturing a brush assembly.

[Conventional technology]

A brush assembly formed by welding a wire made of a large number of fine wires to a spring pedestal, and in particular, a method of manufacturing the brush assembly by continuously supplying a wire is disclosed in, for example, JP-A-56-41680. JP-A-57-212716, JP-A-5-212716
No. 9-42719 and Japanese Utility Model Publication No. 59-30483. In these methods, first, the wire is once welded to a metal piece called a crosspiece, a support plate, a spacer, a connecting piece, etc. to form a sliding brush material or a single brush, and the metal piece is further supplemented to a spring base or the like. Welding, etc.
Secondary welding) to form a brush assembly. Therefore, the manufacturing process is complicated by these methods, and in particular, secondary welding is difficult to automate, and is often performed by a manual operation, so that the dimensional accuracy is inferior. Therefore, there is a functional defect that the weight of the tip of the spring portion (referred to as a spring head) increases. By the way, the effect of the metal piece on the spring head weight of five commercially available brushes alone was examined, and it was found that the metal piece occupied 0.2 to 2.3 of the brush (wire) 1 in weight ratio.

On the other hand, the present inventors, in order to solve such a conventional drawback, while continuously supplying a wire to a substrate in which an integrated spring pedestal is continuously connected, welding the wire directly to the spring pedestal. A method has already been developed and filed.

[Problems to be solved by the invention]

The present inventors have proposed a method of welding a wire directly to a spring pedestal while continuously supplying the wire to a substrate on which an integrated spring pedestal is continuously connected in order to solve such a conventional disadvantage. Has already been developed and filed (Japanese Patent Application No. 62-196562)
No.), a better method is desired.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a brush assembly substrate for efficiently producing a brush assembly of high quality, which eliminates inferior precision and productivity defects particularly due to secondary welding. Another object of the present invention is to provide a method for efficiently manufacturing a brush assembly using the above substrate.

[Means for solving the problem]

The present invention relates to a method of manufacturing a brush assembly by forming a spring pedestal used as a brush assembly in advance into a shape close to the final use shape, and directly welding a wire to the shape without passing through another metal piece. It has been made based on the finding that the use of a substrate on which a spring pedestal preformed in a frame is mounted enables a high-quality product to be continuously produced with good productivity without deformation of the substrate.

That is, in the present invention, the mount portion and the spring portion are indispensable components, a slit is provided on the rear portion near the welding portion at the tip of the spring portion as necessary, and the integrated type molded into a substantially final use shape is provided. The spring pedestal is connected to the frame constituted by the suspension portion and the connecting piece portion at a constant cycle via a connecting portion, and at least one row of projections for attaching a wire is provided at the tip of the spring portion. The present invention provides a brush assembly substrate preformed with an integrated spring pedestal.

Further, the present invention uses the above-described substrate, transfers the wire and the substrate in synchronization, aligns the wire substantially parallel to the projection provided on the substrate, and welds the wire to the projection. And a method of manufacturing a brush assembly, characterized by separating the connecting portion.

Next, a method for manufacturing a substrate and a brush assembly according to the present invention will be described using an embodiment. FIG. 1 is an enlarged schematic view showing a wire member 12 attached to a preformed brush assembly substrate 1 of an integral spring pedestal used in the present invention. In the frame constituted by 3 and 3 ', an integrated spring pedestal 5 is connected to the suspension band 2 through the connecting portion 4 to form one unit, and a plurality of or continuous units are formed. I have.

Further, two rows of projections 9 and 10 are provided at the tip 8 of the spring portion 7 of the spring pedestal 5. The two rows of projections 9 and 10 are described below (FIG. 2).
It is for welding wire 12 consisting of fine wire 11,
In the case of a single row as in the prior art, as the number of brushes increases and the number of wires increases, the probability of poor welding increases, so that this type of component requiring high reliability has two or more rows. Is good. In other words, if two rows are formed, two wires are naturally welded at one location, so that the probability of welding failure at both locations is one-square of that at one location, contributing to significant improvement in reliability. . Projection 9 or
For the 10 shapes, their ridges may be flat and of uniform height, but the A of the projection section shown in FIG.
As shown in FIG. 2, a projection 9 or 10 is formed to have a height of 30 to 50 μm, as shown in FIG. 2 as a cross-sectional view of FIG. Preferably, the angle of the recess 13 is 120 degrees, the pitch between each pitch is substantially the same as the diameter of the fine wire, and the height of the recess is about 30 μm. In the present invention, as shown in FIG. 2, it is desirable that the recess 13 be provided on the projection surface in such a shape that the recess 13 comes into contact with each of the fine wires 11 at at least two points without application of pressure during welding. That is, in this way, the thin wires can be tightly and uniformly welded without displacement of the thin wires at the time of welding, and stable welding strength can be obtained for each of the thin wires. The concave portion provided on the projection is not limited to the one shown in FIG. 2, and may have various shapes such as a semicircle that matches the shape of the fine line. The formation of the concave portion on the projection can be easily performed by a known method, for example, by pressing.

Also, as shown in FIG. 1, in order to facilitate the positioning of welding and pressing, pilot holes are provided at predetermined intervals in the strap 2.
14 can also be provided. FIG. 1B shows a state in which the wire is continuously attached to the substrate, and FIG.
Indicates a state where the wire is cut to a desired length.

As described above, in the present invention, the spring pedestal 5 formed in advance into a complicated shape is mounted in the frame,
Since the substrate is protected, even if the substrate is formed into a continuous elongated shape and wound into a coil shape, there is little possibility that the substrate is deformed. Here, a plurality of spring pedestals can be provided in the frame, but it is preferable to provide one spring pedestal in the frame.

In addition, in the connection part 4, the dotted line shown at the boundary between the spring pedestal and the suspension part indicates a line separated by pressing after welding. The brush assembly thus separated is
There is an excellent advantage that it can be used as it is as a brush assembly only by adding bending or the like as needed.

In the conventional method, as shown in FIG.
After being welded to the metal piece 15, the brush is separated into a brush unit 16 and attached to the spring pedestals 17 and 19 by spot welding as shown in FIG. I was However, in the present invention, such a need is eliminated, labor for secondary welding can be omitted, and there is no room for intervention in accuracy deviation in secondary welding, and an increase in spring head weight due to extra metal pieces is also avoided. Since there is no,
Both workability and quality characteristics are significantly improved.

In the present invention, as shown in FIG. 4, a brush assembly substrate having an integral spring pedestal disposed in a frame and provided with a slit 20 at the spring tip 8 is more beneficial to the effects of the present invention. It is mentioned as a thing to tighten. FIG. 5 shows a cutting state of the wire when the brush assembly is turned over in the case of the embodiment of FIG. 1. The wire is drawn along the outer edge 8 of the spring tip and not to protrude from the edge. Even if the wire is cut into 12, the extra wires remain unequally long for each thin wire at the rear part of the projection 9 which is a welding portion as shown in the figure, and the appearance is poor. Moreover, if the extra wire 12 'that does not function at all remains attached to the rear end,
Although the weight at the tip of the spring portion, that is, the spring head weight, has been reduced as compared with the conventional type using the auxiliary metal piece, there is still room for reduction. Also, an extra weight increase is not preferable from the viewpoint of the mechanism design, and it is uneconomical particularly when an expensive noble metal contact material is used as the wire. Therefore the fourth
As shown in the figure, if a slit 20 is provided behind the projection 9 at a position crossing the wire 12, a cutting blade is inserted into the slit 50, and the wire 12 can be cut neatly there, so that no extra wire is attached to the product. Therefore, the above problem can be solved, and a more preferable brush assembly is provided.

In the embodiment of FIG. 4, connecting portions 4 and 40 are provided at two places of the spring pedestal 5, and the connecting portions 4 and 40
2 ', and a spring pedestal is arranged in a frame surrounded by the straps 2, 2' and the joint pieces 3, 3 'to form one unit. Even if it is treated as a long metal material or the spring pedestal of complicated shape is preformed because it constitutes a band, these are protected by the frame and the connecting part, so handling The deformation inside can be prevented.

In addition, in the connecting portions 4 and 40, the dotted line indicated at the boundary between the spring pedestal and the suspension band indicates a line separated by pressing after welding, and the separated brush assembly is
There is an excellent advantage that it can be used as it is as a brush assembly only by adding bending or the like as needed.

As for the material of the substrate, unlike the conventional method of manufacturing from a continuous substrate of this type, since the present invention uses an integrated spring pedestal, the substrate itself needs to be a spring material. For example, phosphor bronze, perilium copper, titanium-containing copper and the like for copper-based alloys, nickel-based alloys and the like, and nickel-based alloys for stainless steel, and iron-based alloys for stainless steel are preferable, and those having both weldability and corrosion resistance are preferable. .

FIG. 6 shows that the preform spring pedestal 5 has four connecting parts 4, 41, 42, 43, and the straps 2, 2 'and the joint piece 3,
This is an example of a structure connected to 3 ′, and the preform spring pedestal is more excellent in protection stability.

The shape and position of the connecting portion can be appropriately selected depending on the shape of the spring pedestal.

In the present invention, as described above, the shapes and positions of the frame, the suspension part, the joint piece, and the connecting part are not limited as long as the function can stably protect the preform spring pedestal in a continuous welding process or the like. For example, the frame may be rectangular as shown in FIG. 1, barrel-shaped as shown in FIG. 4, or rhombic or pentagonal as shown in FIG. Anything that does is good.

The brush assembly can be manufactured by various methods using the brush assembly substrate on which the above-mentioned integrated spring pedestal is preformed. As a specific example, FIG. 7 shows a schematic view of a method for manufacturing a brush assembly of the present invention. According to this method, the wire 12 composed of seven fine wires having a diameter of 120 μm is supported by a guide 29 and is transferred to the close contact alignment device 30 in a cycle of constant speed feed and temporary stop. The close contact aligning device 30 includes a mechanism for closely contacting and aligning a plurality of fine wires to form a plane. On the other hand, the long substrate 1 separate from the wire 12 passes through the substrate guide 31 and is sequentially sent out in parallel with the alignment surface of the closely aligned and aligned wire 12 and in conjunction with the cycle motion in which the wire 12 is sent out. . The wire 12 and the substrate 1 sent out in conjunction with each other are superimposed on each other in the middle of the transfer. For example, as shown in FIG. Nine recesses 13 are inserted so as to fit one by one.
Therefore, according to this method, the thin wire can be easily located at a predetermined position, closely attached, and a state in which there is no gap between the thin wires 11 can be achieved. Next, the substrate feed roller 32 is used for welding equipment.
Reaches 33. As shown in FIG. 8, the welding device 33 is installed so that each surface of the upper electrode 34 and the lower electrode 35 is parallel to the alignment surface of the wire. Then, the wire 12 to the substrate 1
When the projections 9 and 10 of the substrate 1 stop below the upper electrode 34, the upper electrode 34 descends and the substrate 1
Is pressed, and the tightly aligned wires 12 on the lower electrode 35 are welded to the projections 9 and 10. At this time, according to the present invention, the thin wires are in close contact with each other, and even when pressed by the lowering of the upper electrode 34, the thin wires are firmly fixed in the concave portions, so that the thin wires do not shift, and welding is performed with extremely high precision. There is an advantage that you can. Thereafter, the substrates 1 to which the wires 12 are welded are sequentially transferred and wound up by a winder 36, but are introduced into a press device 37 on the way. The substrate after welding will be described with reference to the example of FIG. 1. As shown in FIG. 1 (A), the wire 12 is punched out by a press 37 to remove an excess wire except for a portion necessary to function as a sliding contact. The connecting portion 4 is punched out with a dotted line, and a brush assembly is obtained in which the wire 12 is directly welded to the integrated spring pedestal. However, in FIG. 1 (A), after the wire 12 is cut, the terminal remains as shown in FIG. 5, as already described.

Therefore, as shown in FIG. 4, when a substrate provided with a slit 20 at the spring tip 8 is used, a cutting edge is inserted into the slit 20 so that the rear end of the wire 12 is a projection portion, which is a welding portion, in the pressing step. It is even more effective because it can be cut behind the side of the 9.

It should be noted that such a pressing step may be performed as a series of steps subsequent to the welding step, as shown in the example, or only the welding may be performed, and after the substrate is once wound up, pressing may be performed in another step.

In the above embodiment, the long substrate 1 is sent out to the upper side of the close contact parallel alignment wire 12. However, in some cases, the long substrate 1 is sent out below the alignment wire 12, the upper electrode 34 descends, and the alignment wire 12 is projected onto the substrate 1. 9 may be pressed and welded.

In the present invention, as the fine wires constituting the wire rod 12, various diameters, for example, 60 to 150 μm can be used, and the number of aligned wires is not limited to 6 or 7, for example, 10 or 80. Etc. can be used.

In the present invention, the fine wires composed of a large number of fine wires can be welded to the substrate while being aligned substantially horizontally, but the wires composed of the large number of fine wires are aligned substantially in parallel to one plane, and the plane is orthogonal to the feed direction of the wire. Substrate to which the thin wire (whose weight is g) is adhered with an axis having an inclination angle (θ) of 15 to 90 °, preferably 30 to 45 ° with respect to a horizontal plane, and transferred in synchronization with the wire. 8, it is possible to apply an acting force (f = g sin θ) in the alignment direction to each fine wire, thereby further improving the adhesion. However, the effective contact force is obtained by reducing the tension, frictional resistance, and the like acting on the fine wire than f, but this f can be used quite effectively by releasing the tension immediately before welding. If θ approaches 90 °, f can be increased to a maximum value. However, it is preferable to select an appropriate inclination angle in consideration of the alignment device and the welding jig.

〔The invention's effect〕

According to the present invention, unlike a conventional method in which a brush is manufactured by first welding a wire to a metal piece and then secondary welding it to a spring base, a single welding is performed on the spring pedestal by a continuous process. Since the wire is directly welded in the process, there is an advantage that the time for the secondary welding can be reduced as well as the weight of the spring head. Further, since the substrate formed in a state very close to the shape of the final spring to be used in advance is used, it is not necessary to cut the spring portions at portions near both side surfaces of the wire welding portion. Therefore, when cutting is performed at a portion near both sides of the related art, a secondary force is applied to a welded portion, and the conventional disadvantages such as deteriorating welding strength and causing loose hairs are eliminated. This leads to the advantage that the variation in accuracy accompanying the above is also eliminated. In particular, since the preformed spring pedestal is formed in the frame, a high quality product can be continuously manufactured with high productivity without deformation of the substrate.

Further, when a slit is formed in the spring portion at the rear portion near the welded portion, the excess wire can be effectively cut, and the disadvantage that the excess wire remains can be eliminated.

In addition, if the alignment plane is inclined by 15 to 90 ° with respect to the horizontal in order to increase the effect of tightly aligning the wire, and a projection having a concave portion is adopted, the wire can be used without using a special pressing device or the like. Since the constituent details easily adhere to each other, the thin wires can be easily welded to the substrate without any gap, and the thin wires do not deviate from a predetermined position on the projection during welding,
Fine wires can be accurately welded on the projection.

Therefore, according to the present invention, the brush assembly can be continuously produced simply and efficiently, which has remarkable advantages in productivity and quality.

[Brief description of the drawings]

FIG. 1 is an enlarged schematic view of a brush assembly substrate obtained by preforming an integral spring pedestal used in the present invention to which a thin wire constituting a wire is welded, and FIG. 2 is an AA cross section of the projection part of FIG. FIGS. 3 (A) and 3 (B) are schematic views showing a conventional brush assembly, and FIGS. 4 and 6 are diagrams showing another example of a brush assembly substrate preformed with an integral spring pedestal used in the present invention. FIG. 5 is a schematic view of the back surface of FIG. 1 (A), FIG. 7 is a view showing a manufacturing process of the brush assembly of the present invention, and FIG. 8 is a manufacturing of the brush assembly of the present invention. It is a partial enlarged sectional schematic diagram of the welding device used in a process. In the figure, 1 is a substrate, 2 'is a suspension band, 3' is a joint portion,
4, 40, 41, 42, 43 are connecting parts, 5 is a spring pedestal, 6 is a mounting part, 7 is a spring part, 9, 10 is a projection, 12 is a wire, 13 is a concave part, 15 is a metal piece, and 16 is a brush. Single unit, 20 is a slit, 30 is a close alignment device, 33 is a welding device, 34 is an upper electrode, 35 is a lower electrode, and 37 is a press device.

Claims (4)

(57) [Claims] 1. A plurality of frames are formed by connecting side portions of two parallel suspension portions at substantially equal intervals by a plurality of joint pieces,
One integrated spring pedestal preformed in each frame
A brush assembly which is connected to the suspension band and / or the connecting piece via one or a plurality of connecting portions, and wherein at least one row of wire mounting projections is provided at the tip of the spring portion of the spring pedestal. Substrate for Lee. 2. The substrate according to claim 1, wherein a slit for cutting an extra wire rod welded to the projection is formed in a spring portion behind the projection. 3. A method of manufacturing a brush assembly, comprising welding a wire made of a large number of fine wires to a substrate, wherein a spring pedestal of the brush assembly comprises a mount portion and a spring portion as a substrate, and is preformed. An integrated spring pedestal is provided in the frame at a fixed cycle via a connecting portion, and at least one row of projections for attaching a wire is provided at the tip of the spring portion, and the wire and the substrate are synchronized. A method of manufacturing a brush assembly, comprising: transferring a wire to a projection provided on a substrate, aligning the wire substantially parallel to a plane, welding the wire to the projection, and separating the wire and the connecting portion. 4. The wire is transported such that a plane formed by parallel arrangement of the wires has an inclination angle of 15 to 90 ° from a horizontal plane with respect to the feed direction of the wire, and the substrate to be tuned and transported with the same inclination angle is transferred to the substrate. The method according to claim 3, wherein the wire is welded.