JPH0451514Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is designed to connect the circuit board and the mounting board when inserting the circuit board, which has a large number of external lead pins fixed by soldering, into the mounting board. The present invention relates to a spacer for a circuit board that forms a constant interval between the spacers.

(Prior art and its problems) Conventionally, this type of spacer 1 has the structure shown in FIG. Spacers 1 are inserted into predetermined positions, for example, lead pins 21 at the four corners, to form a gap between the circuit board 2 and the mounting board 3 for a certain period of time, thereby maintaining a stable conductive state.

The spacer 1 is a ring body made of a desired material and having a desired thickness, and is bored through an insertion hole 11 for insertion into the lead pin 21 from the upper surface to the lower surface, and is opened from the upper surface opening edge 13 of the insertion hole 11 to the lower surface. It is formed in a straight line up to the edge 14.

On the other hand, lead pins 21 fixed to the circuit board 2
A solder layer 23 is formed around it, and a fillet 24 is formed at the upper end of the leg rod 22 protruding from the lower surface of the substrate 2.
is formed.

The spacer 1 is attached to such a lead pin 21.
is inserted, the upper opening edge 13 of the spacer 1
The spacer 1 collides with the fillet 24 and cannot bring the top surface of the spacer 1 into close contact with the bottom surface of the circuit board 2. Therefore, the spacer 1 is inserted into the lead pin 21 in a very unstable state, and as a result, the circuit mounted on the mounting board 3 The mounting accuracy of the board 2 was low, and there was a risk of causing poor conduction.

(Technical problem to be solved by the invention) The technical problem of the present invention, which attempts to solve the above problems, is to form a fillet relief part at the opening edge of the upper surface of the spacer so that the upper surface of the spacer is brought into close contact with the lower surface of the substrate. This is to ensure a predetermined distance between both substrates.

(Means for Achieving the Technical Problem) The means of the present invention for achieving the above-mentioned technical problem is to form the spacer main body into a ring shape using an insulating material, and to form the upper opening edge into a curved surface. A plurality of protrusions are provided on the lower opening edge at equal intervals on the circumference, and the protrusions are made to protrude inward from the lower opening edge by a desired amount.

(Function) According to the above structure, the upper opening edge of the spacer fits into the fillet to tightly fix the spacer to the lower surface of the substrate, and the protrusion on the lower opening edge presses against the outer periphery of the lead pin, preventing the spacer from falling off. prevent.

(Effects) The present invention has the following effects by having the above configuration.

Since the upper opening edge of the spacer is formed into a curved surface, the spacer is stably fixed on the bottom surface of the board, which greatly improves the mounting accuracy of the circuit board mounted on the mounting board, eliminating the risk of conduction failure. Eliminate.

Furthermore, the curved shape of the upper opening edge of the spacer allows the lower end of the lead pin to be easily inserted into the opening when the spacer is inserted into the lead pin.

Since the protrusion on the lower opening edge prevents the spacer inserted into the lead pin from falling off, the process of inserting the spacer into the lead pin can be performed easily and reliably.

(Example) An example of a spacer for a circuit board according to the present invention will be described below based on FIGS. 1 to 3.

In the figure, 1 is a spacer, 2 is a circuit board mounted on the mounting board 3, and 21 is a lead pin fixed to the circuit board.

The spacer 1 is a donut-shaped ring body made of an insulating material such as rubber or synthetic resin.
1 and a ring portion 12.

The insertion hole 11 penetrates from the upper surface to the lower surface of the spacer 1 and is opened so that its inner diameter can be fitted into the leg rod portion 22 of the lead pin 21 protruding from the lower surface of the circuit board 2 .
A lower opening edge 14 is formed on the lower surface.

The ring portion 12 is a contour portion forming the insertion hole 11, and has an upper surface and a lower surface formed into an arcuate curved surface.
The upper opening edge 13 and the lower opening edge 14 are formed into curved surfaces with a substantially elliptical or circular cross section;
Further, a plurality of protrusions 15 are provided on the lower surface.

The protrusions 15 are bowl-shaped protrusions with a circular plan view, and are provided on the lower opening edge 14 of the spacer 1 at equal intervals on the circumference, and the outer periphery of the protrusions 15 protrudes a desired amount to the inner periphery of the opening edge 14. The leg portion 22 of the lead pin 21 whose tip fits into the insertion hole 11
Press to the outer periphery of the

When the spacer 1 is fixed at the upper end of the leg portion 22 of the lead pin 21 protruding from the lower surface of the circuit board 2, the upper opening edge 13 of the spacer 1 is brought into close contact with the lower surface of the fillet 24, and the upper surface of the spacer 1 is attached to the circuit board. 2, and the protrusions 15 are pressed against the outer periphery of the lead pin 21 and the leg rod portion 22, so that the leg rod portion 2
Hold 2.

In this embodiment, both the upper and lower surfaces of the spacer 1 are curved to increase productivity.

[Brief explanation of drawings]

The drawings show an embodiment of the spacer for a circuit board according to the present invention, and FIG. 1 shows a central vertical cross-sectional view of the spacer when it is inserted into a circuit board, FIG. 2 shows a bottom view of the spacer, and FIG. This figure is a bottom view of the conventional spacer for a circuit board, and FIG. 4 is a vertical cross-sectional view of the conventional circuit board spacer, showing the spacer installed on the circuit board. In the figure, the spacer body...1, the upper opening edge...13, the lower opening edge...14, and the protrusion...15.

Claims (1)

[Scope of utility model registration request] The spacer body is made of an insulating material and formed into a ring shape, the upper opening edge thereof is formed into a curved surface, and the lower opening edge is provided with a plurality of protrusions at equal intervals on the circumference,
A spacer for a circuit board, which has the protrusion projecting a desired amount inward from the opening edge of the lower surface.