KR20150040730A - Tape feeder - Google Patents

Abstract

A tape feeder comprises a light sensor including a light emitting part arranged to face a component supported by tape, and a light receiving part; and a control part generating light receiving amount data by converting light receiving information of the light receiving part of a light sensor, wherein the control part performs a teaching step of calculating representative value (R) and standard deviation (σ) from light receiving amount data; and a judgment step of judging as no component when the light receiving amount data is out of the range of R±kσ (k: a constant), judging that a component end part of tape reaches when the judgment of no component is continued for preset times.

Description

Tape feeder

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape feeder, and more particularly, to a tape feeder that feeds a component to a pick-up position of a component mounting apparatus by moving a tape supporting a component at a constant interval (pitch)

In a component mounting apparatus, a method of using a tape feeder as a method for supplying a component to a pick-up position of a nozzle of a moving placement head is known. In this method, a tape for supporting the components at a predetermined interval (pitch) is taken out from the supply reel, and the tape is moved by a predetermined distance in synchronism with the mounting timing of the component to supply it to the pickup position of the nozzle.

In such a method of supplying a component using a tape feeder, it is necessary to supply a new tape to the tape feeder when all the tapes in use are used. To efficiently replace the tape, the component end of the tape in use is detected . In other words, the part is supported by the tape at regular intervals (pitch) along the longitudinal direction of the tape. In the rear part of the tape, there is a so-called trail part in which the part is not supported. After the part terminating part reaches the pickup position of the nozzle, It is preferable for the trailer portion of the trailing end to be quickly discharged from the tape feeder in order to improve the productivity.

Japanese Patent Application Laid-Open No. 2008-277509 discloses a technique of a tape feeder having a component termination detecting portion for detecting a component termination. Japanese Patent Application Laid-Open No. 2008-277509 discloses a component termination detecting portion of a tape feeder which is provided with a transmissive optical sensor. Specifically, the transmission type optical sensor includes a light emitting portion disposed on the upper surface side of the tape, and a light receiving portion disposed on the lower surface side of the tape opposite to the light emitting portion. The spot light from the light emitting portion is blocked by the component, If it is smaller than the light amount, it is judged that the part exists. When the number of times that the part termination detecting unit fails to detect the part (the number of times that the part is not judged to exist) reaches the predetermined number of times during the tape conveying operation, it is determined that the tape is to be replaced.

However, since the component termination detecting unit of Japanese Patent Laid-Open No. 2008-277509 judges the presence or absence of components only by increasing or decreasing the amount of received light, the accuracy of component presence determination is not sufficient. In other words, there is a variation in the amount of received light itself, and there is a variation in the degree of increase or decrease in the amount of received light due to the presence or absence of the component depending on the type of tape (light transmittance) and the shape of the component. Therefore, .

Japanese Patent Laid-Open No. 2008-277509 (November 13, 2008)

It is an object of the embodiments to provide a tape feeder capable of highly accurately detecting that a part terminal of a tape has been reached.

A tape feeder according to an embodiment is a tape feeder that supplies a component to a pick-up position of a component mounting apparatus by moving a tape supporting components at a constant interval (pitch) by a predetermined distance, An optical sensor having a light emitting portion and a light receiving portion disposed so as to face the component; and a control portion for converting received light amount information of the light receiving portion of the optical sensor to generate light receiving amount data,

The control unit includes an initial set step of calculating a representative value R and a standard deviation sigma from the light receiving amount data when the tape is moved at a predetermined distance from the head portion of the tape supporting the part, When the light receiving amount data is out of the range of R 占 σ (k: constant) every time it is moved, it is judged that there is no part and a judgment step of judging that the part terminal end of the tape is reached when the judgment of no part is continued for the predetermined number of times is executed .

The control unit can calculate the representative value R and the standard deviation sigma by selecting the integration method or the peak method at the initial setting step. When the integration method is selected, the control unit integrates the received light amount data The standard deviation sigma is calculated as the representative value R from the value and the control unit calculates the standard deviation sigma from the peak value of the received light amount data every time the tape is shifted by a predetermined interval, The median (median) M can be calculated as the value R and the standard deviation sigma can be calculated.

The control unit can select the integration method when there is at least one maximum value of the A / D conversion in the light-reception amount data acquired in the initial setting step, and if the maximum value of the A / D conversion does not exist in the light- If not, you can choose the peak method.

The control unit can select the peak method and can acquire the light reception amount data by changing the light emission amount of the light emitting portion of the optical sensor to a plurality of levels in the initial setting step and acquire the maximum light emission amount in which the maximum value of the A / (Median) M and the standard deviation (?) From the peak value of the light reception amount data at the level of the light sensor. In the determination step, the light emission amount of the light emitting portion of the photosensor can be set to the maximum light emission amount level.

The control unit can increase the driving speed of the motor that moves the tape constantly when the part terminal of the tape reaches the pickup position.

According to the tape feeder according to the above-described embodiments, the representative value R and the standard deviation? Are calculated from the light reception amount data when the parts are actually present on the tape actually used in the initial setting step, The presence or absence of the component can be judged with high precision, and it is possible to precisely detect that the part end of the tape has arrived.

1 is a side view schematically showing a configuration of a tape feeder according to an embodiment.
Fig. 2 is an enlarged view showing an enlarged view of the tape end sensor portion of the tape feeder according to the embodiment shown in Fig. 1. Fig.
Fig. 3 is an enlarged enlarged view of the tape end sensor portion of the tape feeder according to the embodiment shown in Fig. 1. Fig.
4 is a graph showing an integrated value of the amount of light received by the tape feeder according to the embodiment shown in Fig.
FIG. 5 is a graph showing the peak value of the light reception amount data of the tape feeder according to the embodiment shown in FIG.
Fig. 6 is a graph showing the principle of component presence / absence determination based on the light receiving amount data of the tape feeder according to the embodiment shown in Fig.

Hereinafter, the structure and operation of the tape feeder according to the embodiments will be described in detail with reference to the accompanying drawings. The expression " and / or " used in the description refers to one of the elements or a combination of elements.

1 is a side view schematically showing a configuration of a tape feeder according to an embodiment.

The tape feeder according to the embodiment shown in Fig. 1 includes an elongated box-shaped tape feeder main body 1 and various components described below installed inside the tape feeder main body 1. Fig.

A tape conveying path 2 is provided on the upper portion of the tape feeder main body 1. The tape T is introduced from the tape introduction portion 2a of the tape transport path 2 and guided along the tape transport path 2. [ Although the illustration is omitted, the tape T is supported at a constant interval (pitch) along its longitudinal direction.

A first sprocket (3) is disposed on the downstream end side of the tape transport path (2). The teeth of the first sprocket 3 are engaged with the tape feeding holes provided at regular intervals on the tape T and the first sprocket 3 is rotated by a predetermined angle to move the tape at regular intervals.

The rotary shaft of the first motor 5 is connected to the first sprocket 3 via a plurality of intermediate gears 4 and the first sprocket 3 is rotated by the rotation of the first motor 5. The downstream position of the first sprocket 3 is the pick-up position P of the component.

A second sprocket 6 is disposed on the upstream side of the first sprocket 3 and a third sprocket 7 is disposed on the upstream side of the second sprocket 6. Each of the second sprocket 6 and the third sprocket 7 is engaged with a tape feeding hole provided at a predetermined interval on the tape T and the second sprocket 6 and the third sprocket 7 are rotated So that the tape T is transported along the tape transport path 2.

The second sprocket 6 and the third sprocket 7 are rotated by the rotation of the second motor 8 and the third motor 9 via a plurality of intermediate gears 4, respectively. The rotation of the first motor 5, the second motor 8 and the third motor 9 is controlled by the control unit 10. The types of the first motor 5, the second motor 8 and the third motor 9 are not particularly limited, but a servomotor with an encoder is used in this embodiment.

As a part detection sensor for detecting a part supported on the tape T in the tape conveying path 2 near the second sprocket 6 side between the second sprocket 6 and the third sprocket 7, (11). On the upstream side of the optical sensor 11, a tape end detection sensor 12 for detecting the end portion of the tape T is disposed.

Fig. 2 is an enlarged view showing an enlarged view of the tape end sensor portion of the tape feeder according to the embodiment shown in Fig. 1. Fig.

The optical sensor 11 is a transmissive optical sensor which includes a light emitting portion 11a disposed on the lower surface side of the tape T passing through the tape conveying path 2 as shown in Fig. 2, And a light receiving portion 11b disposed on the upper surface side so as to face the light emitting portion 11a. Therefore, when a component (not shown) supported by the tape T comes to the optical axis position of the optical sensor 11, the spot light from the light emitting portion 11a is blocked by the component, so that the light receiving amount of the light receiving portion 11b is reduced. The light-receiving amount information from the light-receiving unit 11b is transmitted to the control unit 10. [

Fig. 3 is an enlarged enlarged view of the tape end sensor portion of the tape feeder according to the embodiment shown in Fig. 1. Fig.

The tape end detection sensor 12 is a mechanical sensor using a lever 12a as shown in Fig. 3 and has a lever 12a and an optical sensor element 12b. One end of the lever 12a is transported by a tape Is located within the path (2).

When the tip of the tape T reaches one end of the lever 12a, one end of the lever 12a is lifted by the tip of the tape T and rotates around the point 12a-1. Thereby, the sensor element 12b is turned ON, and the tip of the tape T is detected. While the tape T passes, one end of the lever 12a is lifted and the sensor element 12b is also kept ON. Thus, the presence of the tape T is detected. When the rear end of the tape T passes, one end of the lever 12a descends. As a result, the sensor element 11b turns from ON to OFF, and the rear end of the tape T is detected. The tape end detection information by the tape end detection sensor 12 is transmitted to the control unit 10. [

In the above configuration, the control unit 10 detects the presence or absence of a component supported on the tape based on the received light amount information from the optical sensor 11, and detects the arrival of the component end of the tape.

(Example 1)

The process of detecting the arrival of the part terminal end of the tape by the control unit 10 consists of an initial setting step and a judgment step as follows.

(1) Initial setting step

When the loading (mounting) of the tape on the tape feeder is completed, that is, when the leading end of the tape reaches the pickup position P (see Fig. 1), the control unit 10 starts the initial setting step. In this example, it is the initial setting step until the 32 parts are moved by a predetermined distance and supplied from the end of loading of the tape. Thus, the initial setting step is performed at the head portion of the tape on which the part is reliably supported. The end of loading of the tape can be judged by the encoder information of the first motor 5, the second motor 8 and the third motor 9 shown in Fig.

In the initial setting step, the control unit 10 A / D-converts the received light amount information from the light receiving unit 11b of the optical sensor 11 to generate received light amount data. Whenever the tape is moved by a predetermined distance, that is, The representative value R and the standard deviation? Are calculated from the data.

In this example, an " integral method " or " peak method " is used as an algorithm for calculating the representative value R and the standard deviation sigma. Specifically, in this example, the following processing is performed for each component while 32 components pass through the optical sensor 11.

(a) The received light amount information of each part is A / D converted into 12 bits 128 times at regular intervals. Thus, the received light amount information is converted into 128 pieces of received light amount data having values of 0 to 4095, respectively.

(b) 128 pieces of received light amount data are summed up to obtain an integral value of the received light amount data of each part.

(c) The peak values of the 128 received light amount data are obtained. In this example, the peak value is obtained by the moving average. That is, ten moving average values of 128 pieces of received light amount data are obtained, and the maximum value of the moving average is set as a peak value.

At the end of the initial setting step, the control unit 10 selects either "integral method" or "peak method" as an algorithm for calculating the representative value R and standard deviation sigma. Specifically, when there is at least one maximum value (4095) of the A / D conversion in the light-receiving-amount data obtained in the process of (a), the "integration method" is selected, and in the other cases, the "peak method" is selected .

4 is a graph showing an integrated value of the amount of light received by the tape feeder according to the embodiment shown in Fig.

When the " integral method " is selected, the control unit 10 calculates an average value (mu) as a representative value R from the integral value of each component obtained in the process of (b) . An image of the integral value of each component used in this " integral method " is as shown in Fig. 4, and an average value [mu] is calculated from the integral value of each component and a standard deviation [sigma] is calculated. In Fig. 4 and later-described Fig. 5, reference character P denotes a part supported by the tape T. Fig.

FIG. 5 is a graph showing the peak value of the light reception amount data of the tape feeder according to the embodiment shown in FIG.

When the " peak method " is selected, the control unit 10 calculates the median (median) M as the representative value R from the peak values of the respective components obtained in the process (c) ). An image of the peak value of each component used in this " peak method " is as shown in FIG. 5, and a median (median) M is calculated from the peak value of each component, .

When the tape material is transparent (light transmissive), the " integral method " is selected, and in other cases, the " peak method " Therefore, when the tape material is determined, the algorithm may be fixed to "integral method" or "peak method".

(2) Judgment step

When the initial setting step is finished, the judgment step is executed. In this example, the judgment step is executed from the 33rd and following parts, and the following processing is executed for each part.

(d) The received light amount information of each component is A / D converted 128 bits at regular intervals in 12 bits. Thus, the received light amount information is converted into 128 pieces of received light amount data having values of 0 to 4095, respectively.

(e) The integrated values of the received light amount data of each component are summed up to 128 pieces of the received light amount data.

(f) The peak value of the 128 received light amount data is obtained. In this example, the peak value is obtained by the moving average. That is, ten moving average values of 128 pieces of received light amount data are obtained, and the maximum value of the moving average is set as a peak value.

When the " integral method " is selected in the initial setting step, the control unit 10 determines that the part exists when the integrated value of the light-receiving amount data obtained in the process (e) is within the range of 占 k (k: , It is judged that there is no part when the integral value of the light-receiving-amount data is out of the range of 占 k (k: constant).

On the other hand, when the " peak method " is selected in the initial setting step, when the peak value of the light-receiving amount data obtained in the process (f) is within the range of M 占 σ (k: And it is determined that there is no part when the peak value of the light-receiving amount data is out of the range of M 占 σ (k: constant).

The control unit 10 stores the result of the determination of the presence or absence of these components in the 256 ring buffers and determines that the part end of the tape (start position of the trapezoidal part) has reached . Thereafter, the control unit 10 quickly discharges the trail portion of the tape from the tape feeder by increasing the driving speed of the first motor 5 when the part terminal end of the tape reaches the pickup position P (see Fig. 1).

Further, in this example, since the tape end sensor 12 can detect the rear end of the tape, the controller 10 stores the rear end position of the tape detected by the tape end end sensor 12, When the position P is reached, the first motor 5 is quickly driven by a length corresponding to a part of the tape from the component end to the rear end of the tape.

Fig. 6 is a graph showing the principle of component presence / absence determination based on the light reception amount data of the tape feeder according to the embodiment shown in Fig.

Here, k, which is a coefficient of the standard deviation (?) Used for determining the presence or absence of the above-described components, can be set by the following method. First, the integral value (peak value) obtained from the light-receiving amount data of each component is irregular for each component, but if it is assumed that the component has a normal distribution characteristic, the distribution of the integral value (peak value) 6. Theoretically, it is theoretically most error-free to judge the presence or absence of a component with k0 (k0 = (mu n-mu) / (sigma n + sigma e)) obtained by solving the equation of e + Kσe = mu n- However, in actuality, it is a great risk to discard a part by judging that "the part exists" is "no part", so the presence or absence of the part is judged by using a value k slightly larger than k0.

The graph of Fig. 6 needs to be ensured for each tape in advance, and k0 also varies from tape to tape. In this example, k0 obtained in advance from various tapes is taken into consideration comprehensively, and k is a predetermined constant.

(Example 2)

In the above example 1, "algorithm" and "peak method" are selected as algorithms for calculating the representative value R and the standard deviation sigma in the initial setting step. In this example, Quot ;, and the light emission amount of the light emitting portion 11a of the optical sensor 11 is adjusted so that it can correspond to various tapes including the transparent tape in this " peak method ".

(1) Initial setting step

In this example as well, as in the case of the above-described example 1, from the end of the loading of the tape, until the 32 parts are moved by a predetermined distance and fed (feed) is the initial setting step. Then, while 32 components pass through the optical sensor 11, the following processing is performed for each component.

(g) A / D conversion is performed on each of eight components as 25%, 50%, 75%, and 100% of the light emission level of the light emitting portion 11a of the optical sensor 11, respectively. As in the case of the above-described example 1, the A / D conversion is performed on the light receiving amount information of each part at 128 intervals of 12 bits at regular intervals.

(h) The peak values of the 128 received light amount data are obtained. Specifically, as in the case of Example 1, the peak value is obtained by the moving average. That is, ten moving average values of 128 pieces of received light amount data are obtained, and the maximum value of the moving average is set as a peak value.

Next, the control unit 10 confirms whether the maximum value (4095) of the A / D conversion is present in the light receiving amount data for eight of the respective light emission amount levels obtained in the process of (g), and the highest light emission amount level In a later decision step.

At the end of the initial setting step, the controller 10 calculates a representative value R from the peak values of the eight components at the light emission level used in the determination step among the peak values obtained in the process (h) ) (M) and calculates the standard deviation (?).

(2) Judgment step

In this example, similarly to the above-described example 1, the judgment step is executed from the 33rd and following parts, and the following processing is executed for each part.

(i) The received light amount information of each component is A / D converted to 128 bits at regular intervals of 12 bits. Thus, the received light amount information is converted into 128 pieces of received light amount data having values of 0 to 4095, respectively.

(j) Find the peak value of the 128 received light amount data. Specifically, as in the case of Example 1, the peak value is obtained by the moving average. That is, ten moving average values of 128 pieces of received light amount data are obtained, and the maximum value of the moving average is set as a peak value.

Next, when the peak value of the light-receiving-amount data obtained in the process of (j) is within the range of M 占 σ (k: constant), the control section 10 judges that the component exists and if the peak value of the light- (k: constant), it is judged that there is no part.

The subsequent processing is the same as in Example 1, and when the judgment of absence of parts is made three times in succession, it is judged that the part end of the tape (start position of the part of the train) When the pick-up position P (see FIG. 1) is reached, the trailing portion of the tape is quickly ejected from the tape feeder by increasing the driving speed of the first motor 5.

In addition, in the above-described examples 1 and 2, when it is judged that the part end of the tape has been reached immediately after the judgment of absence of parts is made three times in succession, in addition to the condition that the determination of absence of parts is continued three times (predetermined number of times) It is possible to add that the rear end of the tape has been detected by the detection unit 12 and can determine that the part end of the tape has reached when the two conditions are satisfied. Thereby, the probability of occurrence of a five-sensed part of the component terminal end can be reduced.

In this embodiment, the optical sensor 11 as the component detection sensor is a transmissive optical sensor, but it may be a reflective optical sensor. In this case, the light emitting portion and the light receiving portion are disposed so as to face the component on the upper surface side or the lower surface side of the tape. In the case of the reflection type optical sensor, when the part supported by the tape comes to the position of the optical axis of the sensor, the spot light from the light emitting portion 11a is reflected by the component so that the light receiving amount of the light receiving portion increases. Can be detected.

The construction and effect of the above-described embodiments are merely illustrative, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Accordingly, the true scope of protection of the invention should be determined by the appended claims.

1: tape feeder main body 9: third motor
2 tape transport path 10:
2a: tape introduction part 11: light sensor (part detection sensor)
3: First sprocket 11a:
4: Middle gear 11b:
5: first motor 12: tape end detection sensor
6: Second sprocket 12a: Lever
7: Third sprocket 12a-1: Point
8: second motor 12b: sensor element

Claims (5)

A tape feeder for feeding a component to a pick-up position of a component mounting apparatus by moving a tape for holding the component at a predetermined interval (pitch) by a predetermined distance, the tape feeder comprising:
An optical sensor having a light emitting portion and a light receiving portion disposed so as to face the component supported by the tape in the movement path of the tape; And
And a control unit for converting received light amount information of the light receiving unit of the optical sensor to generate received light amount data,
The control unit includes an initial step of calculating a representative value R and a standard deviation sigma from the light reception amount data when the tape is moved at a predetermined distance from the head portion of the tape supporting the part, When the light receiving amount data is out of the range of R 占 σ (k: constant) every time the tape is moved by a predetermined distance, it is judged that there is no part, and when the determination of no part is continued for a predetermined number of times, And judges that the tape feeder has been operated. The method according to claim 1,
The control unit calculates the representative value R and the standard deviation sigma by selecting the integration method or the peak method in the initial setting step,
When the integration method is selected, the control unit calculates the average value (μ) as the representative value (R) from the integrated value of the light reception amount data each time the tape is moved by a predetermined interval, and calculates the standard deviation In addition,
When the peak method is selected, the controller calculates the median (M) as the representative value (R) from the peak value of the light-receiving amount data each time the tape is moved by a predetermined distance, lt; / RTI > 3. The method of claim 2,
Wherein the control unit selects the integration method when at least one maximum value of the A / D conversion is present in the light reception amount data acquired in the initial setting step, and adds the maximum value of the A / D conversion to the light reception amount data acquired in the initial setting step The peak method is selected. 3. The method of claim 2,
Wherein the control unit selects the peak method and acquires the received light amount data by changing the amount of light emitted from the light emitting unit of the photosensor to a plurality of levels in the initial setting step and determines whether the maximum value of the A / (Median) M and standard deviation (?) From the peak value of the light reception amount data at the level of the maximum light emission amount, and in the determination step, the light emission amount of the light emitting portion of the photosensor is set to the level of the maximum light emission amount , Tape feeder. 5. The method according to any one of claims 1 to 4,
Wherein the control section increases the drive speed of the motor that moves the tape at a constant distance when the part terminal of the tape reaches the pickup position.

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