JPH0518826Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a connection structure between an electronic circuit housed in an electronic device and a connection cord drawn out from the electronic device.

[Prior art]

The extraction cords of this type of electronic equipment are often directly connected to terminal patterns of printed wiring boards that are housed inside cases. and,
To assemble the printed wiring board into the case, first connect the cord to the terminal pattern of the printed wiring board by soldering, then pass the cord into the case and pull out the cord from the outlet provided in the case while inserting the printed wiring board into the case. Generally, this is done in the order in which they are stored inside.

[Problem that the invention attempts to solve]

With this method of connecting the cord to the printed wiring board in advance and pulling it out from inside the case, if the cord is long, it takes a lot of time to pass it through the outlet of the case, and when testing electronic equipment. There were drawbacks such as the long cord getting in the way and making testing difficult.

In view of the above, the purpose of this invention is to provide a small electronic device that requires a short time to insert the cord into the case regardless of the length of the cord, and that allows testing without connecting the cord. be.

[Means for solving problems]

In order to achieve the above-mentioned object, this invention provides a small electronic device in which a connection cord connected to a printed wiring board mounted with electronic components housed in a case is led out from a cord outlet of the case. A board seat is provided near the cord outlet and has a guide groove for guiding the core wire of the connection cord to the connection point of the printed wiring board.

[Effect]

Because the case is equipped with a re-plate receiver with a guide groove for guiding the core wire of the connection cord to the connection point on the printed wiring board near the cord outlet, the connection cord can be connected to the printed wiring board in advance. Later, there was no need to store the printed wiring board in a case,
First, the printed wiring board is assembled into the case, and then the cord is inserted from the outside of the case.The core wire of the connection cord is guided to the connection point of the printed wiring board along the guide groove of the board seat, so the connection cord is inserted into the case. The trouble of pulling out the cord through the cord outlet of the case can be omitted.

〔Example〕

Figures 1 to 3 are diagrams showing a photoelectric switch adopted as an example of a small electronic device according to this invention. , FIG. 3 is a perspective view of the main part. In the figure, the inner wall surfaces of case 1 and cover 2 are covered with conductive coating 3 made of conductive paint, aluminum vapor deposition, etc.
covered with. A lens block 5 is attached to the opening 4 on the front side of the case 1 and the cover 2, and a holder is fitted behind the lens block 5, the outer periphery of which is covered with a conductive coating made of conductive paint, aluminum vapor deposition, etc. A light emitting element 7 and a light receiving element 8 are fitted and fixed into installation grooves 6c and 6d having holes 6a and 6b provided on the front side of the holder 6, respectively. A printed wiring board 9 is arranged behind the holder 6 in the case 1.
The two are integrated by press-fitting a protrusion (not shown) of the holder 6 into a through hole (not shown) provided in the holder 6 . The leads of the light emitting element 7 and the light receiving element 8 are directly connected to the printed wiring board 9 by soldering. On the other hand, the holder 6 is provided with a rectangular through hole 6e, and both ends of the through hole 6e protrude from the conductive rubber which electrically connects the conductive coatings 3 on the inner walls of the case 1 and the cover 2 when they are joined. A conductor with elasticity such as An electronic circuit including electronic components 11 for processing signals from photoelectric conversion elements such as the light emitting element 7 and the light receiving element 8 is mounted on the printed wiring board 9 . The joint surface between the case 1 and the cover 2 and the lens block 5 are fixed by ultrasonic bonding or the like. The case 1 is further covered with a transparent cover 16 from the outside in which a light emitting diode 12 for operation display and a photoelectric switch sensitivity adjuster 13 are incorporated together with waterproof gaskets 14 and 15. The transparent cover 16 is caulked by a protrusion 1a provided on the case 1. On the other hand, a cord 20 connected to the terminal pattern of the printed wiring board 9 by soldering passes through a cord outlet 1b penetrating the rear wall of the case 1, and is tightened with a nut 22 via a rubber bush 21. In the case 1, a board receiving seat 1c is provided protruding from the bottom plate near the cord outlet 1b.
The core wires 20a, 2 of the cord 20 are mounted on the board seat 1c.
Guide grooves 1d and 1e are provided to guide the terminal pattern 0b to the land hole of the terminal pattern of the printed wiring board 9.

In the above structure, the photoelectric switch is assembled by incorporating into the case 1 the holder 6 to which the light emitting element 7 and the light receiving element 8 are attached, the light emitting diode 12 for operation display, and the photoelectric switch sensitivity adjuster 13. Thereafter, the printed wiring board 9 is set and the light emitting element 7, light receiving element 8, light emitting diode 12 and sensitivity adjuster 13 are connected by soldering. In this state, the core wire 20 of the cord 20 of the printed wiring board 9
Testing is possible by inserting and contacting the test terminals into the connection land holes of a and 20b.Furthermore, after the test is complete, if the cord 20 with the terminal treated is inserted from the outside into the cord outlet 1b of the case 1, the core wire 20
a, 20b are guided by guide grooves 1d, 1e and reach a predetermined position, allowing soldering connection. Therefore, the cord 20 does not interfere with the test, and the connection work time does not change depending on the length of the cord 20.

[Effect of idea]

According to this invention, by providing an interior accessory seat with grooves to guide each core wire on the inside near the cord outlet of the case, it becomes possible to connect the cord at the final stage of assembly, making testing easier and providing a small electronic device with a consistent assembly time regardless of the length of the cord.

[Brief explanation of drawings]

Figures 1 to 3 are diagrams showing a photoelectric switch adopted as an example of a small electronic device based on this invention. Figure 1 is a plan view showing the entire cross section, and Figure 2 is a vertical cross sectional view of the main part. , FIG. 3 is a perspective view of the main part. 1... Case, 1b... Cord outlet, 1c...
... Board seat, 1d, 1e... Guide groove, 9... Printed wiring board, 20... Cord, 20a, 20b
...heart line.

Claims (1)

[Scope of utility model registration request] In a small electronic device in which a connection cord connected to a printed wiring board housed in a case and mounted with electronic components is led out from a cord outlet of the case, a connection point of the printed wiring board is located near the cord outlet in the case. A small electronic device characterized in that a substrate receiving seat having a guide groove for guiding the core wire of the connection cord is provided in the device.