JPH04282900A - Lead lifting detector of flat package-type electronic component - Google Patents

Abstract

PURPOSE:To detect a lead lifting of FP-type electronic components accurately in a short time by a simple structure. CONSTITUTION:Laser light from a light emitting device is reflected at right angles on the plural number of reflectors 61, 62, 63 in succession and is allowed to reach a photo-detecting device 5. At that time, a PF-type electronic component P is put in a loop of the laser light and the laser light is allowed to skim just above or below a lead line of each side of the electronic component P. When the laser light which is supposed to reach the photo detecting device is cut off on the way to the device, a longitudinal bend of the lead is detected. Meanwhile, a silimar loop is formed with band laser light of a certain width. The FP-type electronic component is put in a loop of the band laser light and the band laser light is allowed to cross the lead line of each side of the electronic component. By comparing a detected quantity of the band laser light supposed to reach the photo detecting device, a part of which is cut off by the lead lines, with a reference detected quantity of light, a longitudinal bend of the lead is detected.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to a device for detecting lead bending of flat package type IC devices, and particularly,
The present invention relates to a device for detecting longitudinal bending of a lead.

0002

[Prior Art] Conventionally, when a flat package (hereinafter abbreviated as FP) type IC is surface-mounted on a printed circuit board, if the leads of the FP-type IC are mounted with bends, poor contact or short circuit may occur after solder reflow. It was occurring. As a method to deal with this, various methods have been proposed in which lead bending is detected before surface mounting and only normal products are supplied.

For example, in Japanese Patent Application Laid-Open No. 64-21372, a television camera is scanned across the lead rows of an FP type IC, and the video output current of a normal lead row is compared with the video output current of an article to be inspected. I'm trying to check and detect lead bends.

[0004] Also, in Japanese Patent Application Laid-Open No. 1-260349,
A laser beam emitter and a light receiver facing each other are arranged diagonally across the lead row of the FP IC, and the lead row is irradiated with laser light from an oblique direction. This laser beam is strip-shaped, covers the entire lead array within its irradiation range, and transmits the laser beam uninterrupted between the leads to the receiver. Then, the light receiver attempts to detect lead bending by comparing the amount of light received by the normal lead array and the amount of light received by the lead array of the article to be inspected.

[0005]

[Problem to be Solved by the Invention] In the former method, the television camera is scanned along the lead rows on each side, or
Alternatively, a mechanism is required to sequentially move the lead rows on each side of the FP IC to the imaging center of the television camera. Furthermore, the video output current changes depending on the surface condition of the lead, which may lead to incorrect determination.

In the latter method, although the inspection time is short, the lead rows on each side are sequentially moved within the laser beam irradiation range and positioned with high precision, or the pair of emitter and receiver is moved between the leads. It is necessary to provide a number corresponding to each side of the protruding column.

[0007]

[Means for Solving the Problems] In the device for detecting floating leads of a flat package type electronic component of the present invention, a laser beam irradiated from a light emitting means is bent in a right angle direction one after another by a plurality of reflectors. At the same time, an FP type electronic component is placed in this laser beam loop, and the laser beam is grazed directly above or directly below the lead rows on each side of the component.
The vertical bending of the lead is detected when the laser beam that should reach the light receiving means is interrupted midway. Also,
A similar loop is formed with a belt-shaped laser beam of a constant width, and an FP type electronic component is inserted into this belt-shaped laser beam loop, and is passed across the lead rows on each side to reach the light-receiving means. The amount of received light of the band-shaped laser beam that is blocked is compared with a reference amount of received light to detect vertical bending of the lead.

[0008]

[Operation] In this way, by forming a laser beam loop with a plurality of reflectors and a pair of laser emitting/receiving means,
without moving FP type electronic components on the same plane.
The vertical bending of the lead rows on each side can be detected with high accuracy all at once.

[0009]

[Embodiment] An embodiment of the present invention will be explained based on the drawings.

FIG. 1 is a perspective view showing an embodiment of the "lead floating detection device for flat package type electronic components" of the present invention.
2 and 3 are a plan view and a side view of the main part,
The lead floating detection device 1 for FP type electronic components includes a base 2,
Holding means 3, light emitting means 4, light receiving means 5, reflectors 61, 6
2, 63, and a control section 7. P is a four-direction FP type IC that is the object to be detected.

The holding means 3 consists of a holding table 31 and a driving means 32, and is provided on the base 2. The driving means 32 is a linear motion mechanism driven by a pulse motor, and reciprocates the holding table 31 in the vertical direction at a constant pitch. The holding table 31 holds the object P to be detected.
Only the bottom surface of the package part is supported horizontally, and the package part is suctioned and held by the vacuum suction hole 311 provided on the top surface of itself. The vacuum suction hole 311 is connected to a vacuum source (not shown).

The light emitting means 4 is provided on the base 2, and extends from one end of the first lead row a protruding from one side of the object P to the other in parallel with the lead row a. A linear laser beam is irradiated so as to graze the upper surface of the tip of lead row a. Reflectors 61, 62, and 63 each bend the laser light emitted by the light emitting means 4 at right angles, and are provided around the holding table 31 on the base 2. The first reflector 61 bends at right angles the laser beam that the light emitting means 4 irradiates so as to graze the upper surface of the tip end of the lead row a, and the second lead row protrudes from one side surface adjacent to the aforementioned one side surface. Let it graze the top surface of the tip of b. The second reflector 62 is the first reflector 6
The laser beam received from 1 is further bent at a right angle to graze the upper surface of the tip of the third lead row c protruding from the side opposite to the one side. Similarly, the third reflector 63
bends the laser beam received from the second reflector 62 at a right angle, causes it to graze the upper surface of the tip of the lead row d protruding from the other side adjacent to the one side, and transmits the laser beam to the light receiving means 5. . That is, the reflectors 61, 62, and 63 form a laser beam loop that completely surrounds the top surface of the lead array in four directions of the object to be detected P with the laser beam irradiated by the light emitting means, and the laser beam is transmitted to the light receiving means 5. will be conveyed. The light receiving means 5 is provided on the base 2 so as to be located on the extension line of the optical axis of the laser beam transmitted by the third reflector 63,
It outputs to the control section 7 whether or not the laser beam has been received.

The control section 7 controls a handling means (not shown) to place the object P to be detected on the holding table 31 so as to be located in the center of the laser beam loop, and then connects the vacuum source, the light emitting means 4, and the drive. controlling means 32; Then, the vertical bending of the lead is determined based on the output signal of the light receiving means 5.

The operation of this embodiment having such a configuration will be explained based on FIGS. 3 and 4.

First, by a handling means (not shown), the object P to be detected, which is a four-way FP type IC, is placed on the holding table 31 so as to be located in the center of the laser beam loop described above. At this time, the control unit 7 causes the vacuum suction hole 311 to communicate with a vacuum source (not shown), and causes the detection object P to be suctioned and held on the holding table 31. Then, the light emitting means 4 is caused to irradiate a laser beam, and as shown in FIG.
2 and 63, respectively, to form a rectangular laser beam loop and reach the light receiving means 5. Initially, the holding table 31 is at the origin position, and at this position, the upper surface of the lead array tip of the object to be detected P on the holding table is close enough to graze the laser beam loop. Next, the control unit 7 drives the driving means 32 to lower the holding table at a predetermined pitch,
During this period, if the light receiving means 5 does not detect interruption of the laser beam, it is determined that there is no vertical bending of the lead row. However, as shown in FIG. 4, if some of the leads are bent upward, the laser beam will be emitted between the time when the light emitting means 4 emits the laser beam and the holding table is lowered at a predetermined pitch. There is a period when the light does not reach the light receiving means because it is blocked by the bent lead. The light receiving means that detects the interruption of the laser beam outputs an interruption detection signal to the control section 7, and the control section 7 determines from this signal that the lead has been bent in the vertical direction. Then, based on the result of this determination, the control section 7 sends only those leads with no vertical bends to the next process such as component mounting, and discharges those with vertical bends to the outside of the process.

[0016]Also, while we have described the case of detecting the upward bend of the lead in the vertical direction,
If a downward bend is also to be detected, the above-mentioned holding table 31
A second light emitting/receiving means is provided on the base 2 to form a second laser beam loop that grazes the bottom surface of the leading end of the lead row at the position where it descends at a predetermined pitch and stops, and detection can be performed in the same manner. .

Furthermore, as shown in FIG. 5, if the holding table 31 is constructed in the same manner using a light emitting means for emitting a band-shaped laser beam having a constant width and thickness and a light receiving means for receiving the light, the holding table 31 can be There is no need to move the package part of the object to be detected vertically, just by holding it horizontally. That is, a belt-shaped laser beam is irradiated so that the lead row crosses approximately the center thereof, and a belt-shaped laser beam loop is formed by each of the reflectors. When the lead row is normal, the amount of received band-shaped laser light transmitted to the light receiving means 5 is reduced by the amount blocked by the side surface of the lead row, as shown in FIG. If the lead row is bent in the vertical direction as shown in FIG. 6, the upward or downward bent leads will block additional laser light, and the amount of band-shaped laser light transmitted to the light receiving means 5 will be lower than normal. It becomes less. The light receiving means 5 then photoelectrically converts the received laser light and outputs it to the control section 7. The control unit 7 electrically compares a preset reference light amount with the amount of light received from the object to be detected obtained from the light receiving means 5, and determines whether or not the lead is bent in the vertical direction.

Although the FP type electronic component shown in this embodiment is of a type having lead rows on four sides, the present invention can also be applied to a type in which lead rows protrude only from two opposite sides. Application of the device is possible. In this case, it is not necessary to make the laser beam draw a perfect loop, but rather an incomplete U-shaped loop.
There is no problem. In addition, this embodiment uses a surface-mounted FP.
Although the detection of vertical bending of the lead of a type electronic component has been described, it can also be easily applied to an FP type electronic component for insertion by changing the position of the laser beam loop or changing the posture of the band-shaped laser beam loop.

[0019]

As described above, according to the present invention, lead floating detection of FP type electronic components can be performed accurately in a very short time with a simple structure. This makes it possible to reduce the time required to install parts.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a lead floating detection device for an FP type electronic component according to the present invention.

FIG. 2 is a plan view of essential parts showing an embodiment of a lead floating detection device for an FP type electronic component according to the present invention.

FIG. 3 is a partially cutaway or cutaway side view showing an embodiment of a floating lead detection device for an FP type electronic component according to the present invention.

FIG. 4 is a side view illustrating a lead floating detection operation in the embodiment.

FIG. 5 is a side view illustrating another embodiment of the example.

FIG. 6 is a side view illustrating a lead floating detection operation in another embodiment.

[Explanation of symbols]

1 Lead floating detection device 2 Base 3 Holding means 4. Light emitting means 5 Light receiving means 61, 62, 63 Reflector 7 Control section

Claims (2)

[Claims] 1. A device for detecting vertical bending of a lead of a flat package type electronic component using a laser beam, the device comprising: a light emitting device that irradiates a laser beam directly above or directly below a lead row from the side direction of the lead. a plurality of reflectors that successively bend the laser light at right angles to form a laser light loop that goes around all the lead rows; and a light receiving means that receives the laser light transmitted by the plurality of reflectors; The flat package type electronic component is held at the center of the laser beam loop, and the lead array is controlled by a holding means that brings the lead array closer to or away from the laser beam, and whether or not the laser light grazing directly above or directly below the lead array is blocked. 1. A lead floating detection device for a flat package type electronic component, comprising: determining means for determining vertical bending of a flat package type electronic component. 2. A device for detecting vertical bending of leads of flat packaged electronic components using laser light, the device comprising: emitting a band-shaped laser light having a constant width and thickness onto a lead row from the side direction of the leads; a light emitting means for irradiating; a plurality of reflectors that bend the band-shaped laser beam one after another at right angles to form a band-shaped laser beam loop that goes around all the lead rows; and a band-shaped laser beam transmitted by the plurality of reflectors. holding means for holding the flat package type electronic component at the center of the belt-shaped laser beam loop; and reception of the belt-shaped laser beam that reaches the light-receiving unit and is partially blocked by the lead row. What is claimed is: 1. A lead floating detection device for a flat package type electronic component, comprising a determining means for comparing the amount of received light with a reference amount of received light to determine whether it is good or bad.