JP2570536Y2 - PCB mounting structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable mounting structure for a printed circuit board, and more particularly to a cable mounting structure for a printed circuit board when a cable having fixed terminals is automatically soldered to the printed circuit board.

[0002]

2. Description of the Related Art FIGS. 4 to 7 are views for explaining a conventional mounting structure of this kind. In FIG.
A coaxial cable 1 includes a core wire 11 as a signal line and a mesh wire (not shown) as a ground line. 2 is a fixed terminal provided on the tip of the cable 1, the cable
(1) An annular grip that grips the wire at the tip and connected to it
And a substantially Ω-shaped fixed foot 21 which also serves as a ground terminal.
You. Reference numeral 3 denotes a printed board, and reference numeral 4 denotes a mounting land provided on the surface of the board 3, in which a through hole 5a for the fixed foot 21 is formed. Reference numeral 6 denotes a thermal land for heat transfer provided around the through hole 5b for the core wire 11, and a hatched portion of 7 denotes a resist layer covering the surface of the substrate 3. FIG.
(B) shows a state in which the cable 1 is soldered to the printed circuit board 3 and completed. FIG. 4 shows a conventional mounting structure of this type. In soldering, the fixing feet 21 are fitted into the respective through holes 5a, and the core wires 11 are fitted into the through holes 5b so as to be mounted on the board 3. The cable 1 is temporarily attached. Then, as shown in FIG. 5, the solder is moved from the lower surface of the substrate 3 to the through holes 5a, 5b
The core wire 11 and the fixed foot 21 are soldered in the through holes 5a and 5b. FIG. 6 is a cross-sectional view showing a state where the through holes 5a and 5b are filled with solder. FIG.
FIG. 6B shows a cross section in a direction along the cable 1.

[0003]

In the conventional printed circuit board cable mounting structure as described above, the mechanical fixing strength is weak and causes a failure of the device. That is, in the conventional structure, mechanical fixing strength is secured mainly by soldering the fixing foot 21. However, the fixing foot 21 has a bent shape so as to be difficult to come off when fitted and mounted in the through hole 5a. Therefore, the solder is hardly lifted up in the through hole 5a, and stable mounting of this portion cannot be performed by automatic soldering. As a method of improving the solder drip, there is a method of performing soldering at a high temperature. However, performing the soldering at a high temperature adversely affects other mounted electronic components due to heat. Further, even if the solder is successfully lifted up and stable mounting is performed, the device is assembled mainly as shown by arrows in FIG. Sometimes, when stress is applied, it is easily deformed, and the mounting strength is further reduced. Therefore, there is a problem that it cannot be used for a device to which strong vibration is constantly applied, such as an in-vehicle GPS receiver.

The present invention has been made to solve such a problem, and a printed circuit board cable capable of sufficiently securing mechanical fixing strength even by automatic soldering by making a minimum change to a conventional structure. It is intended to provide a mounting structure.

[0005]

According to the present invention, there is provided a cable mounting structure for a printed circuit board, wherein a thermal land for heat transfer is newly provided below the resist layer also around the mounting land formed on the printed circuit board. In addition, one or more through holes for solder rising are newly provided near the fixed terminal contact portion of the mounting land.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. 1 to 3 are views for explaining an embodiment of the present invention. The same reference numerals as those in FIGS. 4 to 6 denote the same or corresponding parts. In FIG. A through hole for solder newly provided near the contact portion of the fixed terminal 2 and a thermal land 6a for heat transfer provided around the through hole 5b for the core wire 11 correspond to the thermal land 6 of the conventional structure. Reference numeral 6b denotes a thermal land for heat transfer provided around the mounting land 4. FIG. 1B shows a state in which the cable 1 is completed by soldering the printed circuit board 3. The structure of this embodiment is shown in FIG.
At the time of soldering, each fixing foot 21 is connected to each through hole 5a in the same manner as in the conventional structure.
The cable 1 is temporarily mounted on the substrate 3 by fitting the core wire 11 into the through hole 5b. Then, as shown in FIG. 2, the solder is blown up from the lower surface of the substrate 3 into the through holes 5 a, 5 b, 5 c by moving on the automatic solder spout layer 9 in the direction of the drawing arrow, and fixed to the core wire 11. At the same time as the legs 21 are soldered in the through holes 5a and 5b, the solder blown up into the through holes 5c overflows to the surface of the substrate 3 and solders and fixes the contact portion with the fixed terminal 2. FIG. 3 is a view showing the state of attachment of the solder 8 in the present embodiment, and is a view corresponding to FIG. 6 in the conventional structure. As is clear from FIG. Since the entire contact portion with the cable 3 is fixed by the solder 8, the fixing strength of the cable 1 is dramatically increased. Further, since the through hole 5c is a hole even after the cable 1 is temporarily mounted, the solder is well lifted.
Since the thermal land 6b for heat transfer is provided on the entire periphery, stable mounting can be performed even by automatic soldering.

[0007]

[Effects of the Invention] As described above, the present invention can secure sufficient mechanical fixing strength even by automatic soldering by making a minimum change to the conventional structure. For example, as in an in-vehicle GPS receiver, There is an effect that sufficient seismic strength can be ensured even in a device that is constantly subjected to severe vibration.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing an automatic soldering process in the embodiment.

FIG. 3 is a diagram showing a state of solder adhesion in the embodiment.

FIG. 4 is a diagram showing a conventional structure.

FIG. 5 is a view showing an automatic soldering process in a conventional structure.

FIG. 6 is a view showing a state of adhesion of solder in a conventional structure.

FIG. 7 is a view showing a defect of a conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cable 2 Fixed terminal 3 Printed circuit board 4 Mounting land 5a, 5b, 5c Through hole 6a, 6b Thermal land 7 Resist layer 11 Core wire 21 Fixed foot

Claims (1)

(57) [Scope of request for utility model registration] (1)Connect to the annular grip that grips the wire
Substantially Ω-shapedFixed terminals with fixed feetFor coaxial cable
e,Mounting land formed on printed circuit boardofSulhoe
Insert the fixed foot into the, The lower part of the gripTothe aboveMounting la
Contact with the
And solder the above fixed feet.Above coaxialKe
Cable mounting structure of printed circuit board
For heat transfer around the mounting landThermalLandSetting
KeAbove mounting landWith the lower part of the gripNear the contact
For one or more solder liftsNoLe HallProvided,  When solderingFor solder aboveTo Sur Hall
Pour the solder above the fixed terminalThe grip section of the aboveAlso soldering
Cable mounting structure of printed circuit board characterized by its structure
Build.