JP2794391B2 - Ground pattern grounding device for printed circuit board with pin jack - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground pattern grounding device for a printed circuit board having a pin jack, and the grounding device discharges static electricity from the pin jack to the printed circuit board. .

[0002]

2. Description of the Related Art Generally, in a VTR (video tape recorder), a chassis made of resin is used as a chassis. For the purpose of electromagnetic shielding, the chassis is covered with a conductive member called a cover bottom over the bottom surface and a part of the side surface, the front surface, and the back surface from the bottom surface. A printed circuit board called an operation board on which operation switches and pin jacks of the VTR are provided is attached to the chassis via the cover bottom on the front side thereof. Incidentally, since the pin jack can be exposed from the VTR, the operator may touch the pin jack. Then, due to the contact, static electricity of the operator reaches the operation board, and there is a possibility that an integrated circuit on the board or another integrated circuit connected to the board may be destroyed.

For this reason, conventionally, a grounding metal plate, a lug shield wire, or the like, which is to be electrically connected to a ground pattern of the operation board to the cover bottom to be grounded, has been used. Incidentally, apart from the above-mentioned grounding, the ground pattern is electrically connected to a mechanical chassis made of metal and grounded. However, if the ground position on the ground pattern is not between the pin jack and the integrated circuit, the integrated circuit will be destroyed, and in order to release the static electricity, there may be some electrical resistance. For this reason, the grounding means for releasing the static electricity is usually provided independently.

[0004]

The sheet metal spring for grounding and the shield wire with lug, which have been conventionally used as the grounding means, are sufficient for the function of grounding static electricity. Disadvantageously expensive. SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned disadvantages and to provide a relatively inexpensive printed circuit board ground pattern grounding device which has a sufficient function of grounding static electricity and is relatively inexpensive.

[0005]

A ground pattern grounding device for a printed circuit board according to the present invention for solving the above problems and achieving the above object is a printed circuit board mounted so as to overlap a plate-shaped conductive member. A ground pattern of a printed circuit board having a pin jack connected to the conductive member to discharge static electricity from the pin jack to the printed circuit board to the conductive member; The board has a through portion, a jumper wire disposed so as to straddle the through portion, and connected to the ground pattern, and a thickness of the printed board, which is provided in the through portion and is in contact with the jumper wire. A coil spring having a diameter larger than that of the printed circuit board. Roots and is characterized in that it has to be in contact with the conductive member.

[0006]

In the printed circuit board ground pattern grounding apparatus constructed as described above, even if an operator's finger touches the pin jack and static electricity flows to the printed circuit board ground pattern, the static electricity flows from the jumper wire to the ground pattern. Through the coil spring. For this reason, the destruction of the integrated circuit on this printed board or another printed board connected to this board is prevented.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view of a side surface of a main part near the operation board of the VTR, FIG. 2 is a front view thereof, and FIG. 3 is an enlarged view of a main part of FIG. The operation board 1 is provided with a pattern (not shown) including a known ground pattern,
Other components such as a pin jack 2, an operation switch, and an integrated circuit (not shown) are attached. Further, a hole 3 is formed in the operation board 1 and the hole 3 is formed.
, Two jumper wires 4a and 4b are provided in parallel. At least one of these jumper wires 4a and 4b is connected to the ground pattern. The ends of the coil spring 5 are hooked on these jumper wires 4a and 4b. The diameter of the coil spring 5 is slightly larger than the thickness of the operation board 1.

The operation board 1 is mounted on a resin-made chassis 7 via a cover bottom 6 made of a conductive member, as is well known. Then, by this mounting, the coil spring 5 comes into contact with the cover bottom 6. As described above, when the coil spring 5 is in contact with the cover bottom 6, the operator's finger 8 touches the pin jack 2, and static electricity is generated on the operation board 1.
This static electricity reaches the cover bottom 6 via the coil spring 5 and does not destroy the integrated circuit as described above.

In the first embodiment, the penetrating portion for arranging the coil spring 5 is constituted by the hole 3.
Alternatively, a notch (not shown) may be formed. In the first embodiment, two jumper wires 4a and 4b are provided. However, as shown in FIG. 4, one jumper wire 4 is provided, and this jumper wire 4 is connected to the ground pattern and a coil spring 5 is provided. May be hooked, and the other end of the coil spring 5 may be hooked on the small hole 9 of the operation board 1. In the first embodiment, the end of the coil spring 5 is hooked on the jumper wires 4a and 4b. However, as shown in FIG.
Projections 11a and 11b are left at both ends of the
The coil spring 5 may be fitted to the jumper wires 4a and 4b in this state. Further, in the first embodiment, the case where the conductive member is the cover bottom 6 has been described. However, the present invention can be implemented even when the conductive member is a conductive chassis.

[0010]

As described above, in the printed circuit board ground pattern grounding apparatus having the pin jack according to the present invention, the printed circuit board such as the operation board 1 mounted so as to overlap with the plate-shaped conductive member such as the cover bottom 6 is used. A ground pattern of a printed circuit board having a pin jack 2 connected to the conductive member to discharge static electricity from the pin jack to the printed circuit board to the conductive member; On the printed board, there are penetrating portions such as holes 3 and jumper wires 4, 4a, 4b arranged so as to straddle the penetrating portions and connected to the ground pattern.
A coil spring 5 installed in the penetrating portion and having a diameter larger than the thickness of the printed circuit board and in contact with the jumper wire;
Since the coil spring 5 is brought into contact with the conductive member in a state where the printed circuit board is mounted as described above, static electricity generated when an operator touches the pin jack 2 is advantageously released. Inexpensive grounding device can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a first embodiment of the present invention.

FIG. 2 is a front view showing the first embodiment of the present invention.

FIG. 3 is an enlarged front view of a main part showing the first embodiment of the present invention.

FIG. 4 is an enlarged front view of a main part showing a second embodiment of the present invention.

FIG. 5 is an enlarged front view of a main part showing a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Operation board 2 Pin jack 3, 10 hole 4, 4a, 4b Jumper wire 5 Coil spring 6 Cover bottom 7 Housing chassis 8 Operator's finger 9 Small hole 11a, 11b Projection

Claims (1)

(57) [Claims] 1. A printed circuit board which is mounted so as to overlap a plate-shaped conductive member, wherein a ground pattern of a printed circuit board having a pin jack is connected to the conductive member, and static electricity from the pin jack to the printed circuit board is formed. A ground pattern grounding device for a printed circuit board, wherein the printed circuit board has a penetrating portion, a jumper wire disposed so as to straddle the penetrating portion and connected to the ground pattern, and the penetrating portion. And a coil spring having a diameter larger than the thickness of the printed circuit board, which is in contact with the jumper wire, and the coil spring is attached to the conductive member with the printed circuit board attached as described above. A ground pattern grounding device for a printed circuit board, wherein the ground pattern is grounded.