KR19980016951A - Surface Mount Parts - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount component (SMD) mounter. In the related art, a vacuum level when a component is correctly adsorbed to a pressure sensor of a digital output method is manually set in advance. It was a form of outputting a low potential below, such a digital pressure sensor has a problem in that it is difficult to uniformly tune and the load on the main controller due to the large number of electrical lines.

Therefore, the present invention uses an analog pressure sensor to determine whether or not the component adsorption is determined by manually converting the analog output value corresponding to the degree of vacuum into a digital value through an analog / digital converter without using manual setting. Not only can there be a lot of clearance and mis-adsorption, but also the level of supplied pressure can be sensed, so that when the pressure drops, the measured value can be relatively compensated.

In addition, the vacuum sensing control unit located in the head is responsible for all the input and output related to the head, which can dramatically reduce the length of the electric line to the existing head, which facilitates the electric field work, reduces the risk of disconnection of the electric line and reduces the duct. Being able to design has the effect of reducing the overall weight of the head.

Description

Surface Mount Parts

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount component (SMD) mounter. In particular, an analog output value corresponding to a vacuum degree is converted into a digital value through an analog / digital converter without manually setting whether to adsorb the component using an analog pressure sensor. By converting and using it, there is a lot of room for judging whether the part is adsorbed, and it is possible not only to determine whether it is misadsorbed, but also to sense the level of the supplied source pressure so that it is suitable for relatively compensating the measured value when the source pressure drops. A surface mount component (SMD) mounter.

In general, a printed circuit board (PCB) adopts a method of inserting a board into a component, but in recent years, a surface mount is mounted on a PCB instead of inserting a component in accordance with a demand for compact and lightweight products. Is changing.

Surface Mounting Technology improves mounting density by miniaturizing components, miniaturization of printed circuit boards, cost savings due to miniaturization of products, improvement of electrical characteristics due to reduction of component lead length and wiring, and easy introduction of automation lines. Productivity can be increased, which is very advantageous for small quantity production of various kinds.

A machine that mounts such Surface Mounting Devices (hereinafter referred to as SMD) on a PCB with high precision is called an SMD mounter.

In general, the SMD mounter uses a nozzle in the head to suck the parts supplied through the feeder, absorbs them using a vacuum, and moves the head to a predetermined position to mount the parts.

At this time, the pressure sensor is used to determine whether the component is correctly adsorbed on the nozzle.

In other words, it is determined whether the inside of the nozzle is vacuumed.

Then, the prior art will be described with reference to FIG.

Conventional SMD mounters include a head 21 for adsorbing a component from a feeder using a nozzle and then mounting on a PCB, a pneumatic cylinder 22 for driving the head 21, and a pneumatic cylinder ( 22, the solenoid valve SV1 for applying the drive signal to the nozzle, the solenoid valve SV2 for the nozzle SV3, and the vacuum degree when the head 21 adsorbs the components correctly are set manually in advance. A head portion 20 constituted by a pressure sensor 23 outputting a low potential when the value is higher than or equal to a preset value; It is composed of a main controller 10 for overall control of the mounter by reading the output value of the head unit 20 pressure sensor (VS) (23) to proceed to the next sequence, the operation of such a conventional SMD mounter will be described. I would like to.

First, when a driving signal is applied to the pneumatic cylinder 22 by turning on the solenoid valve SV1, the pneumatic cylinder 22 drives the head 21, and the head 21 feeds the parts to be mounted using the nozzles (feeder). Absorb from the feeder and mount it on the PCB.

Subsequently, when the suction solenoid valve (SV2) connected to the output port of the main controller 10 is turned on and sucks the air from the nozzle, if the component is adsorbed correctly, a vacuum is generated inside the nozzle. It is the basis for judging adsorption

The digital output pressure sensor VS sets the vacuum degree when the component is correctly adsorbed in advance and determines that the component is not adsorbed correctly when the measured vacuum degree is less than that.

In other words, if the degree of vacuum is above a certain value, “1” is outputted, and if it is below, “0” is outputted. The digital vacuum pressure sensor (VS) 23 of the digital type has a high potential lower than or equal to a preset value. , Outputs a low potential output.

This output value is read from the input port of the main controller 10 to proceed to the next sequence.

Blow solenoid valve VS3 blows the air pressure inside the nozzle to quickly break the vacuum and shorten the time the parts fall.

In addition, the reed switch (S1) (S2) attached to the pneumatic cylinder 22 is linked to the pneumatic cylinder 22 to check the up / down of the head 21 moving up and down.

However, with the conventional digital pressure sensor 23 as described above, it is difficult to maintain the preset value even with wear of the nozzle or slight deformation of the part, and the setting value when the nozzle is changed even though the parts are correctly adsorbed. Because of this slight difference, there is a problem that it is difficult to set with a uniform manual.

In particular, there is no way to compensate for this when the level of supplied air pressure drops.

In addition, the electrical lines required for solenoid valve drive and head up-down sensing must rise from the bottom of the mounter to the head. Therefore, as the number of heads increases, the number of lines increases proportionally, which increases the size of the duct, which hinders movement and increases the risk of disconnection. In addition, since it is necessary to secure as many input and output ports as necessary, there is a problem in that the main controller.

The present invention was devised to solve the above-mentioned conventional problems, and the analog output value corresponding to the degree of vacuum is digitally set through the analog / digital converter without manually setting whether to determine the adsorption of components using an analog pressure sensor. By converting the value into a value, there is a lot of room for determining whether it is adsorbed, and it is possible to determine whether it is misadsorbed.In addition, by sensing the level of the supplied source pressure, an SMD mounter can be relatively compensated for when the source pressure drops. The purpose is to provide.

1 is a block diagram of a conventional surface mount component (SMD) mounter.

Figure 2 is a block diagram of a surface mount component (SMD) mounter of the present invention.

* Description of the symbols for the main parts of the drawings *

100: main controller 200: head portion

210: vacuum sensing control unit 211: microprocessor

212: analog to digital converter 213: input circuit

214: output circuit 220: pressure sensor

230: head 240: pneumatic cylinder

VS1, VS2: Pressure sensor SV1 to SV3: Solenoid valve

As shown in FIG. 2, the SMD mounter of the present invention for achieving the above object includes a head unit for absorbing a surface mount component (SMD) to be mounted on a printed circuit board (PCB), and an output value of the pressure sensor in the head unit. In the SMD mounter consisting of a main controller for controlling the mounter, such as by determining the adsorption and misadsorption by proceeding to the next sequence, the head portion is composed of two pressure sensors to measure the degree of vacuum in the nozzle during the component adsorption Pressure sensor unit to measure the pressure, and converts the analog value measured by the pressure sensor unit to a digital value and then control the vacuum level to determine whether or not to adsorb the components and comprises a vacuum sensing control unit responsible for all the thrust in the head portion do.

In addition, the vacuum sensing control unit is synchronized with the control unit at the time of initial operation based on a database in which the vacuum level is stored for each nozzle, and adjusts the vacuum level value according to whether or not the actual component adsorption to determine whether the component is adsorbed and supplied pressure A microprocessor that senses the level of the sensor and compensates the measured value relatively when the source pressure drops, an analog / digital converter that converts the analog value measured by the pressure sensor into a digital value, and an input circuit part that performs input / output related to the head / It consists of an output circuit part.

The SMD mounter of the present invention configured as described above will be described in more detail with reference to FIG. 2 as follows.

The present invention intends to introduce an analog pressure sensor and a controller for processing thereof, in order to overcome the problems of the conventional digital type vacuum sensor and difficult to tune many electrical lines, the main control unit located at the bottom of the main body of the mounter In (100), the RS-232C serial communication line and the power line are connected to the head unit 200 through the XY duct, which is referred to as a vacuum sensing controller (VSC) located in the head unit 200. (210) and the main controller 100 is synchronized with each other during the initial operation of the system and performs the operation as the main controller 100 in accordance with a predetermined protocol, the operation of measuring the vacuum degree of the nozzle during the adsorption of components Is the same as

First, some initial data conditions for using the analog sensor VS1 and VS2 are determined as follows.

1. Store the vacuum level values when nozzles are inserted or not.

2. The vacuum level value when only the nozzle is inserted is stored for each nozzle.

3. Determine the vacuum level when the components are adsorbed correctly.

For more accurate data, the vacuum level must be stored in a database with a combination of nozzles and components, but the amount of data becomes so large that it is practically impossible. Therefore, the present invention is limited to storing the vacuum level for each nozzle, and at the beginning of the system, the vacuum level is transferred from the main controller 100 to the VSC 210 in the head 200.

The value when such a vacuum level value is actually used as a basis for judging whether or not components are adsorbed is adjusted with a slight margin. In other words, if it is determined that there is a part, adjust it slightly lower than the actual value.

In addition, the supply pressure is always monitored to correct the set vacuum level when the external pressure or the three axes simultaneously adsorb components and the supply pressure is lowered.

As such, when the original pressure drops, the measured value can be relatively compensated, thereby increasing the reliability of the judgment.

Next, an operation of the SMD mounter including the analog sensor VS1 and the VSC 210 for controlling the same will be described.

First, when a driving signal is applied to the pneumatic cylinder 240 by turning on the solenoid valve SV1, the pneumatic cylinder 240 drives the head 230, and the head 230 feeds a part to be mounted using a nozzle. It is adsorbed from the feeder and then mounted on the PCB.

Subsequently, when the suction solenoid valve SV2 connected to the output port of the vacuum level controller 210 is turned on to suck in the air of the nozzle, a vacuum is generated inside the nozzle when the components are correctly adsorbed.

At this time, the analog pressure sensor 220 measures the vacuum degree of the nozzle. Since the analog pressure sensor VS1 (VS2) is used, it corresponds to the vacuum degree without setting a manual determination of adsorption of components as in the prior art. The analog output value is converted into a 10-bit digital value through the analog-to-digital converter 212 of the VSC 210, and the average value is taken in consideration of noise and the like.

By margining this conversion value, there is a relatively large amount of margin in determining whether or not to adsorb parts, and it is possible to determine not only the presence or absence of parts but also misadsorption.

In addition, by sensing the level of the source pressure supplied, the measured value can be compensated relatively when the source pressure drops, thereby increasing the reliability of the judgment. Also, whether the nozzle is correctly inserted into the desired head due to the difference in the inner diameter of the nozzle can be used as the output value. You can check it.

As described above, the present invention does not use the analog pressure sensor to manually determine whether or not the adsorption of the component by using the analog output value corresponding to the degree of vacuum by converting the digital value through an analog / digital converter to use the component adsorption There is a lot of room to determine whether or not to determine whether the mis-adsorption, as well as sensing the level of the supplied source pressure has the effect of relatively compensating the measured value when the source pressure drops.

In addition, the vacuum sensing control unit located in the head is responsible for all the input and output related to the head, which can dramatically reduce the length of the electric line to the existing head, which facilitates the electric field work, reduces the risk of disconnection of the electric line and reduces the duct. Being able to design has the effect of reducing the overall weight of the head.

Claims (2)

Total control of the mounter by adsorbing the surface mount component (SMD) and mounting it on the printed circuit board (PCB), and reading the output value of the head pressure sensor and determining whether or not the adsorption and misadsorption proceed to the next sequence. In the surface mount component (SMD) mounter consisting of a main controller, the head portion is composed of two pressure sensors, the pressure sensor for measuring the vacuum degree in the nozzle in the analog method when the component is adsorbed, and the analog value measured by the pressure sensor unit To a digital value, and then control the vacuum level to determine whether or not the component is adsorbed, and the surface mount component (SMD) mounter, characterized in that composed of a vacuum sensing control unit responsible for all the input and output in the head portion. The vacuum sensing controller of claim 1, wherein the vacuum sensing controller is synchronized with the controller during an initial operation to determine whether the component is absorbed by adjusting a vacuum level value according to whether the component is actually absorbed based on a database in which the vacuum level is stored for each nozzle. It is responsible for the microprocessor that senses the level of the source pressure supplied and compensates the measured value relatively when the source pressure drops, the analog / digital converter for converting the analog value measured by the pressure sensor into a digital value, and the input / output related to the head. Surface mount component (SMD) mounter characterized in that the input circuit portion / output circuit portion configured.