JPH05145224A - Printed circuit board - Google Patents

Abstract

PURPOSE:To provide a printed circuit board that is so designed that its electrode parts can easily receive deviated leads of a circuit component to be mounted. CONSTITUTION:Electrodes 3 and lead-positioning protrusions 2 are alternately disposed on a substrate 1. The protrusions have side walls sloping down toward the adjacent electrodes on which solder 4 is applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board, and more specifically, a lead position regulating protrusion is formed between electrode portions of a circuit pattern on the substrate, and a wall surface of the protrusion on the electrode portion side is formed on the electrode portion. The present invention relates to a structure in which a lead of an electronic component can be reliably landed on the solder portion by forming an inclined surface having a downward slope toward the formed solder portion.

[0002]

2. Description of the Related Art As a means for forming a solder portion on an electrode portion on a substrate, there are a solder leveler method and a cream solder printing method. When the solder portion is formed by these construction methods, the upper surface of the solder portion is curved in a semi-circular shape. Therefore, when an electronic component is attracted to the nozzle of the transfer head of the chip mounter and the lead of this electronic component is landed on the upper surface of this solder portion, the lead slides on this curved upper surface and shifts from the solder portion. There was a problem that it was easy to fall.

Therefore, as shown in FIG. 5, a lead position regulating projection 102 is formed between the electrode portions 103 on the substrate 101. In this way, when the lead L lands on the solder portion 104 on the electrode portion 103 and the lead L is likely to slip off from the solder portion 104 (see FIG. 5).
(See the solid line), the lead L is the lead position control projection 102.
It abuts against the side surface 102a of the above and cannot be further displaced, and is prevented from falling.

[0004]

However, the above-mentioned conventional lead position regulating projection 102 is formed in a prismatic shape and has the following problems. That is, as shown by the chain line in FIG. 5, when the lead L is landed on the solder portion 104 in a state where the lead L is slightly displaced from the solder portion 104, the lead position regulating protrusion 102 There is a problem in that the tip of the lead L abuts on the edge of the upper surface 102b of the above, and the lead L cannot land on the solder portion 104.

Therefore, an object of the present invention is to provide a printed circuit board which can correctly land the lead on the electrode portion even if the lead is slightly displaced from the electrode portion.

[0006]

To this end, according to the present invention, a lead position regulating protrusion is formed between an electrode portion formed on a substrate and the electrode of the lead position regulating protrusion. The wall surface on the side of the portion is an inclined surface that slopes downward toward the solder portion formed on the electrode portion.

[0007]

In the above structure, when an electronic component is sucked by the nozzle of the transfer head and mounted on the substrate, if the lead is slightly misaligned with respect to the electrode portion, the lead lands on the inclined surface, and this inclined surface By being guided down to the solder portion side while sliding down, the positional deviation is corrected and the land is landed on the solder portion.

[0008]

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a state in which an electronic component is landed on a printed circuit board according to an embodiment of the present invention. A printed circuit board 1 has a circuit pattern 5 formed on its upper surface. Reference numeral 3 denotes an electrode portion of the circuit pattern 5, on the upper surface of which a solder portion 4 is formed by a solder leveler method, a cream solder printing method, or the like. Between the electrode part 3 and the electrode part 3,
The lead position regulating projection 2 is formed. As shown in FIG. 2, the wall surface 2 a of the protrusion 2 on the solder portion 4 side is an inclined surface having a downward slope toward the solder portion 4.

In the above structure, the electronic component P is sucked by the nozzle 11 provided at the tip of the transfer head 10 of the chip mounter, and the transfer head 10 is relatively moved with respect to the substrate 1 in the XY directions (arrows in FIG. 1). (Refer to FIG. 3), the lead L is joined to the solder portion 4, and the lead L of the electronic component P is landed on the solder portion 4. Here, as shown by the chain line in FIG. 2, when the lead L is slightly displaced from the solder portion 4 on the electrode portion 3, the side end portion L1 on the side where the lead L is displaced is located.
Lands on the inclined surface 2a of the lead position regulating protrusion 2, but the lead L is slid down along the inclined surface 2a and guided to the solder portion 4 side to correct the positional deviation, and Correctly land on the part 4 (see the solid line in FIG. 2).

FIG. 3 shows a manufacturing process of the printed circuit board 1. In FIG. 3A, reference numeral 1'denotes a substrate main material, and a copper foil 3'is formed on the upper surface thereof. Next, the circuit pattern 5 and the electrode portion 3 are formed by etching (FIG. 3).
(B)). Next, a photocurable solder resist 2'is formed on the entire surface of the substrate main material 1 '(FIG. 3C). Next, the upper surface of the resist 2'is covered with the exposure film 20. The exposure film 20 has a light-shielding portion 21 and a light-transmitting portion 22 formed therein. The light-shielding portion 21 wider than the electrode portion 3 is provided above the electrode portion 13, and the light-transmitting portion 22 is provided as the electrode portion 3. It is located above the electrode part 3 respectively. And the light source 23
When the light is emitted, the light emitted from the light source 23 passes through the scattering means 24 such as frosted glass to become scattered light, and the scattered light reaching the light transmitting portion 22 reaches the resist 2 ′ below the exposure film 20. The scattered light reaching the light blocking portion 21 is blocked by the light blocking portion 21 and does not reach the resist 2 ′.

Here, as shown by a chained arrow in FIG. 4A, which is an enlarged view of the portion A (inside the broken line) in FIG.
The scattered light that has passed through is diffracted at the lower end edge of the translucent portion 22 and advances in the resist 2 ′ while being inclined with respect to the thickness direction of the substrate main material 1 ′. Therefore, in the resist 2 ′, the resist 2′a in a region surrounded by the left and right chain line arrows in FIG. 4A and the upper and lower surfaces of the resist 2 ′ is solidified by the exposure, and the remaining resist 2'b remains unsolidified.
Then, the exposed film 20 is removed, and the resist 2 ′ is washed with a developing solution. As shown in FIGS. 4B and 3E, the unsolidified resist 2′b is removed,
The protrusion 2 for controlling the lead position by the solidified resist 2'a
Is formed. As described above, the diffracted scattered light inclines with respect to the thickness direction of the substrate main material 1'and exposes the resist 2 ', so that the lead position regulating projection 2 is formed in a chevron cross section, and the solder portion is formed. It is possible to form the inclined surface 2a that has a downward slope toward 4.

[0012]

As described above, according to the present invention, the lead position regulating projection is formed between the electrode portion formed on the substrate and the electrode portion, and the electrode portion of the lead position regulating projection is formed. Since the wall surface on the side is an inclined surface that slopes downward toward the solder portion having a semi-cylindrical cross section formed on this electrode portion, even if the lead is slightly misaligned with respect to the electrode portion, the lead will form an inclined surface. The positional deviation is corrected by being guided along the solder portion side, and the lead can be reliably landed on the solder portion formed on the electrode portion.

[Brief description of drawings]

FIG. 1 is a perspective view showing a state in which an electronic component is landed on a printed circuit board according to the present invention.

FIG. 2 is an enlarged front view of the same.

FIG. 3 is a manufacturing process diagram of the same printed circuit board.

FIG. 4 is a partially enlarged view of FIG.

FIG. 5 is a front view of conventional means.

[Explanation of symbols]

 1 substrate 2 lead position regulating protrusion 2a inclined surface 3 electrode portion 4 solder portion

Claims (1)

[Claims] 1. A lead position regulating protrusion is formed between electrode portions formed on a substrate, and a wall surface of the lead position regulating protrusion on the electrode portion side is formed on the electrode portion. A printed circuit board, characterized in that it has an inclined surface that is downwardly sloped toward the solder portion formed on.