JPS641887B2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement in a method for manufacturing a switch.

In the conventional manufacturing method for switches such as electromagnetic relays, contacts are attached to both sides of a lead frame, and the lead frame is sequentially fed to the next process, so the contacts on the pedestal surface side rub against the pedestal, causing contact failure. It is inevitable that the surface will become rough. If this contact with a rough surface is used as it is in a switch,
This may cause problems such as poor contact and welding. Further, since the contacts must be fixed to both sides of the lead frame, it is necessary to turn the lead frame over and perform the work of fixing the contacts. Therefore, a device or the like for turning the front and back sides of the lead frame is required, which poses a problem of positioning when turning the lead frame, and has the drawback of poor productivity.

In addition, some conventional manufacturing methods involve bending the lead frame itself, shrinking it, and drawing the contacts together so that they face each other. If the lead frame is sequentially sent to the next process while being connected to the processed part, the lead frame cannot be bent until it is separated before the lead frame bending process. This is because if the lead frame itself is bent and shrunk in a later process, the lead frame in the previous process will be distorted by the amount of shrinkage. In this way, conventionally, when the lead frame bending process is reached, the lead frame must be cut and separated before the bending process is performed, which requires an extra lead frame cutting process and requires a long time between the cutting process and the bending process. The machine that transports the lead frame is
This method has the disadvantage of poor productivity, as it is required separately from the machine that feeds the lead frame sequentially.

An object of the present invention is to provide a method for manufacturing a switch that does not damage the contact surface, facilitates lead frame positioning, etc., and can manufacture a highly productive and highly reliable switch. .

Hereinafter, an embodiment in which the manufacturing method of the present invention is applied to manufacturing an electromagnetic relay will be described with reference to the drawings. 1 to 5 show a first embodiment. First, a good conductor metal plate is punched out using a pressing process or the like, and the terminal pieces 11, 12, 14 are shaped as shown in FIG. A lead frame 1 is formed which integrally includes a fixed piece 12b, a coil connecting piece 14a connected to a terminal piece 14, and a bridge portion (including an outer frame portion) that bridges all of these terminal pieces 11, 12, and 14. In addition,
In this embodiment, in this pressing process, when forming the terminal pieces 11, 12, 14, etc. by punching,
At the same time, continuous protrusions 15 for reinforcement are formed on the terminal pieces 11, 12, and 14 (these protrusions 15 protrude toward the back side of the paper in FIG. 1), and their tips are A punched portion (hole) 16 is formed around the periphery. This hole 1
6, the shapes of the tip portions of the terminal pieces 11, 12, and 14 are created. And like this, the protrusion 15
The reason why the thin tip portion is formed at the same time as the thin tip portion is to ensure that the central protrusion 15 of the thin tip portion is positioned correctly. That is, if the protrusion 15 and the hole 16 around the tip of the protrusion 15 are formed at the same time during this pressing, the positional accuracy of the tip shape relative to the protrusion 15 can be easily obtained (such holes 16 are formed around the protrusion 15). If they are not provided at the same time, the shape of the tip of the terminal will be determined in the final step of cutting the bridge portion, but in this case it is difficult to improve the positional accuracy with respect to the protrusion 15). Since the movable piece 13 is a spring piece (see FIG. 5), it is preferable to form the movable piece 13 thinly by pressing or the like during punching to form a deformed member in order to increase its elasticity.

Next, on the back side of this lead frame 1 (the front side of the paper in FIG. 1), as shown in FIG.
Contacts 12a and 13a are fixed to the tip of fixed piece 12b and the tip of movable piece 13, respectively. These contacts 12a and 13a are made of, for example, a composite material with noble metal exposed on the surface, and are fixed by welding, caulking, or the like.

Furthermore, the base of the movable piece 13 (near the area continuous with the terminal piece 11) is bent at 180 degrees, and the movable piece 1
3 should face the back side of the paper in Figure 1. By doing this, it will become as shown in Fig. 2, and the contact point 1 of the movable piece 13
3a faces the back side of the paper and faces the contact 12a of the fixed piece 12b facing the front side of the paper, and both of these contacts 12a and 13a come into contact with each other (see also FIG. 5). In addition, the shapes of the fixed piece 12b and the movable piece 13 are determined during the punching process, and the shapes of both the contacts 12a and 13a are determined during the contact fixing process so that the contacts 12a and 13a face and contact each other when bent.
determine the position of During this bending process, the coil connecting piece 14a connected to the terminal piece 14 is bent at right angles to the back side of the paper in FIG.

Thereafter, the lead frame 1 formed as shown in FIG. 2 is inserted into a mold, and the terminal pieces 11, 1
A frame-shaped base 2 made of insulating synthetic resin is insert-molded so that the bases 2 and 14 are included, and the crosslinked part is not included (on the outside of the base 2). (see figure). The base 2 has a rectangular frame shape as a whole and is open upwardly and downwardly, and a barrier section 21 located between a large number of movable pieces 13 is formed integrally with the base 2. This barrier portion 21 is formed parallel to the movable piece 13 so as to connect the left and right side walls in FIGS. 3 and 4. As shown in FIG. 5, this barrier part 21 is formed mainly in the lower part of the frame-shaped base 2, and is interposed between each of the many contact structures made up of the contacts 12a and 13a. It functions to prevent short circuits caused by arcs. Furthermore, since the barrier portion 21 is formed to connect both side walls of the frame-shaped base 2, it serves to improve the mechanical strength of the base 2.
In addition, the coil connecting piece 14 of the terminal piece 14 for the coil
As shown in FIG. 5, a extends from the top of the side wall located above and below in FIG. It's getting old.

The lead frame 1 integrally having the base 2 in this manner is transported using the lead frame 1 as a carrier, and is transferred to the next step of assembling the contact drive unit and the like. Although the contact drive section is not shown, it consists of a movable section that pushes down the movable piece 13 and an electromagnet device for driving this movable section.
It is housed in the upper open space of the base 2.

After the assembly is completed in this way, in the final step, the bridge portions of the terminal pieces 11, 12, 14 that protrude outside the base 2 are cut as shown by dotted lines in FIGS. 3 and 4. As a result, the outer frame portion of the lead frame 1 is removed, and the terminals held by the base 2 and protruding outward from the base 2 are completely formed. In this way, multiple mutually independent contact configurations are created at once.

In this embodiment, all the movable pieces 13 are connected to the terminal piece 11 located on the right side, but if the movable piece 13 is configured to be connected to the terminal piece 11 on the right side and the terminal piece 12 on the left side in an alternating manner, it will always be possible to A closed contact and a normally open contact will be formed. It is also possible to form a switching contact structure by connecting one side of adjacent terminal pieces forming a normally closed contact and a normally open contact within the base 2 to short-circuit them.

Next, while referring to Figures 6 to 9,
An example will be described. In this embodiment as well, a lead frame 3 as shown in FIG.
However, the shapes of the movable pieces 34 and 35 are different from those of the first embodiment. That is, these movable pieces 34 and 35 are continuous from the terminal piece 31 in a T-shape. The shapes of the other terminal pieces 32, 33, 36, the fixed pieces 32b, 33b, and the coil connection piece 36a that follow these, the terminal pieces 31, 32, 33,
The shape of the crosslinking portion that crosslinks all 36 is almost the same as in the first embodiment.

Thereafter, on the back side of the lead frame 3 (the front side of the paper in FIG. 6), as shown in FIG. and the tip of each.

Next, by bending the movable pieces 34, 35
By bending the base connected to the terminal piece 31 at 180 degrees, as shown in FIG.
a overlap and face each other so that they are in contact with each other.

Then, as shown in FIGS. 8 and 9, a frame-shaped base 4 is molded from an insulating synthetic resin so as not to include a bridge portion. In this case, a barrier section 41 (see FIG. 9) is vertically formed integrally with the base 4 at the center of the frame-shaped base 4 in FIG. 8, and the two contact configurations are separated by this barrier section 41. Ru.

The lead frame 3 with the base 4 molded in this manner is transported using the lead frame 3 as a carrier, and is transferred to the next step of assembling a contact drive section (not shown). The contact drive section is housed in the upper open space of the base 4 (see FIG. 9), and its movable section moves in seesaw motion to push either one of the movable pieces 34, 35.

When the assembly process of this contact drive unit is completed,
The final step, the step of cutting the bridge, is performed. That is, the bridge portions connected to the terminal pieces 31, 32, 33, and 36 are cut along dotted lines and removed, and the lead frame 3 is dismantled. By cutting such a bridge portion, the terminal pieces 31, 32,
33 and 36 are formed into perfect shapes. In the electromagnetic relay of this embodiment, the terminal piece 31 serves as a common terminal, the terminal pieces 32 and 33 serve as a normally closed terminal and a normally open terminal, and the terminal piece 36 serves as a coil terminal.

In the above two embodiments, a case where a large number of contact structures are formed simultaneously is described, but the present invention can also be applied to a case where there is only one contact structure (a case where there is one pair of a movable piece and a fixed piece). Of course, it can also be applied to cases where the number of contact points is larger than in the above embodiment, but in that case, the amount of materials will increase and the material cost will increase accordingly, but the manufacturing cost will be reduced because the processes and operations are exactly the same. There is almost no increase.

As described above with respect to the embodiments, according to the method for manufacturing a switch of the present invention, the contacts are fixed to the same side of the lead frame, so when the lead frame is moved to the next process, the contact fixed surface is moved upward. If the contact points are oriented in the opposite direction, it is possible to manufacture a switch having a contact point that does not damage the contact surface and does not impair the contact reliability of the contact point. In addition, the base of the fixed piece or movable piece of the lead frame is bent approximately 180 degrees so that each contact point faces each other, so that only the base of the fixed piece or movable piece is bent.
This means that the lead frame itself does not have to be bent. Therefore, the lead frame is press-formed simultaneously using multiple molds, the multiple pressed parts are sequentially sent to the next process, the contacts are fixed to the multiple parts at the same time in the next process, and then the next process If the contacts are made to face each other, the lead frame does not need to be bent, and the lead frame in the previous process will not be adversely affected. As a result, according to the manufacturing method of the present invention, a switch can be manufactured using an extremely highly productive process in which processing is performed sequentially while feeding, and finally cutting is performed to separate each piece. can.

[Brief explanation of drawings]

1 to 5 show a first embodiment of the present invention, in which FIG. 1 is a plan view showing the back side of the lead frame after contact fixation and before bending, and FIG. 2 shows the lead after bending. A plan view showing the front surface of the frame, FIGS. 3, 4, and 5 show the lead frame after resin molding. FIG. 3 is a plan view showing the front surface, and FIG. 4 is a plan view showing the back surface. , FIG. 5 is a sectional view taken along the line A-A in FIG. 3, FIGS. 6 to 9 show the second embodiment, and FIG. 6 shows the back side of the lead frame before bending after the contacts are fixed. 7 is a plan view showing the surface of the lead frame after bending, FIGS. 8 and 9 show the lead frame after resin molding, and FIG. 8 is a plan view showing the surface. FIG. 9 is a sectional view taken along the line B--B in FIG. 8. 1, 3...Lead frame, 11, 12, 1
4, 31, 32, 33, 36...Terminal piece, 12
b, 32b, 33b... fixed piece, 13, 34, 3
5... Movable piece, 12a, 32a, 33a... Fixed side contact, 13a, 34a, 35a... Movable side contact, 2, 4... Base, 21, 41... Barrier part.

Claims (1)

[Claims] 1. A bridging part that bridges the whole, a terminal piece, a fixed piece, a movable piece, and a coil connecting piece that are connected to the bridging part are connected by holes around the tips of the terminal pieces and holes around the fixed piece, movable piece, and coil connecting piece. forming a lead frame by punching out a single good conductor metal plate, fixing contacts to the fixed piece and the movable piece on the same side of the lead frame, and fixing the fixed piece or Abbreviation for the base of the movable piece
a step of arranging the contacts of the fixed piece and the movable piece so as to face each other by bending them at 180 degrees; A method for manufacturing a switch, comprising the steps of: integrally attaching the lead frame to a base by resin molding; and after attaching to the base, cutting the bridge portion to remove the lead frame.