JP6788687B2 - Board detector - Google Patents

Description

The present invention relates to a substrate detection device provided in a substrate production machine that conveys a substrate along an in-machine transport path.

As a board production machine that produces a board on which a large number of electronic components are mounted, there are a solder printing machine, an electronic component mounting machine, a reflow machine, a board inspection machine, and the like. It has become common to connect these board production machines to construct a board production line. Each substrate production machine is equipped with a substrate detection device to check the transfer status of the substrate in the transfer path. As a substrate detection device, a method using detection light is often used. That is, the substrate detection device projects the detection light toward a specific position on the transport path, and determines the presence of the substrate from the fact that the detection light is blocked or reflected by the substrate. A technical example of this type of substrate detection device is disclosed in Patent Document 1.

The substrate crack detection device of Patent Document 1 includes an irradiation means for irradiating a conveyed substrate with light, a light receiving means, a signal output means for outputting a signal based on the light receiving state, and the presence of the substrate based on the signal. In addition, it has a means for detecting cracks in the substrate, and the signal output means outputs a signal having a time width larger than that corresponding to the cracks in the substrate. According to this, when the substrate is cracked, the light receiving state changes from the state with the substrate to the state without the substrate, and a signal with a large time width is output, so that the crack is reliably detected. ing.

JP-A-2007-225323

By the way, the temperature of the light projecting unit exemplified by the irradiation means of Patent Document 1 fluctuates up and down immediately after the power is turned on or due to a temporary interruption of operation, and the light projecting amount fluctuates with time. Therefore, if the substrate production machine continues to produce the substrate, the amount of received light depending on the amount of projected light may fluctuate with respect to a certain amount of threshold light for determining the existence of the substrate, which may cause an erroneous determination. As a result, it is determined that the transfer of the substrate is abnormal, and the production of the substrate is stopped.

In order to prevent a transport abnormality, in the prior art, a state in which the substrate does not exist in the transport path is ensured at regular time intervals, and the light receiving amount of the light receiving portion at that time is obtained and the threshold light amount is reset. However, this resetting requires an operation interruption to temporarily stop the loading of the substrate. Further, in the prior art, even if the substrate production machine continues to operate and the temperature and the amount of the light projecting are stable, the operation is interrupted unnecessarily and the amount of the threshold light is reset. Due to such an operation interruption, the production efficiency of the substrate production machine is lowered.

The present invention has been made in view of the above-mentioned problems of the background technology, and has solved the problem of providing a substrate detection device that does not reduce the production efficiency by setting the threshold light amount without interfering with the operation of the substrate production machine. It is an issue to be done.

The substrate detection device disclosed in the present specification is a transport path for transporting a substrate, and is arranged so as to face a specific position of the transport path provided in a substrate production machine that works on the substrate. A light projecting unit that projects detection light toward the substrate, a light receiving unit that is arranged facing the specific position and receives the detected light to obtain the amount of light received, and an operating time zone during which the substrate production machine is operating. A time zone grasping unit for grasping an absent time zone in which the substrate cannot exist at the specific position, a determination time zone excluding the absent time zone from the operating time zone, and the absent time zone. A setting unit that sets a threshold light amount for determining whether or not the substrate exists at the specific position based on the received light amount obtained in the determination time zone and does not set the threshold light amount in the determination time zone, and the determination time. The amount of received light obtained in the band is compared with the amount of threshold light to determine whether or not the substrate exists at the specific position, and it is determined not to determine whether or not the substrate exists in the absence time zone. The specific position is the entrance of the transport path, and the determination result of the determination unit changes from "the substrate exists" to "the substrate does not exist" during the absence time zone. from the carry end of the first of said substrate, the time zone to a known working time predetermined length of required for the work to the first of said substrate has passed, or from the carry-end, when the work industry It is a time zone until a certain period of time, which is shorter than the interval, elapses.
Further, the substrate detection device is a transport path for transporting the substrate, and is arranged so as to face a specific position of the transport path provided in the substrate production machine that works on the substrate, and detects toward the specific position. A light projecting unit that emits light, a light receiving unit that is arranged facing the specific position and receives the detected light to obtain the amount of light received, and a part of an operating time zone in which the substrate production machine is operating. The time zone grasping unit for grasping the absence time zone in which the substrate cannot exist at the specific position and the determination time zone excluding the absence time zone from the operation time zone, and the absence time zone were obtained. Based on the received light amount, the threshold light amount for determining whether or not the substrate is present at the specific position is set, and the setting unit for not setting the threshold light amount in the determination time zone and the determination time zone are obtained. A determination unit that compares the amount of received light with the amount of threshold light, determines whether or not the substrate exists at the specific position, and does not determine whether or not the substrate exists during the absence time zone. The specific position is the exit of the transport path, and the third said in the absence time zone, the determination result of the determination unit changes from "the substrate exists" to "the substrate does not exist". short from the carry-out end of the substrate, the time zone to a known working time predetermined length of required for the working of the fourth of the substrate has passed, or, from the unloading end, than during the time of the operation industry It may be a time zone until a certain time elapses.

According to the substrate detection device disclosed in the present specification, the light receiving portion of the light receiving unit receives light during the absence time zone in which the substrate cannot exist at a specific position of the transport path, which is a part of the operating time zone in which the substrate production machine is operating. The amount can be calculated. Since the obtained light receiving amount is the light receiving amount when it is known that the substrate does not exist, the threshold light amount can be appropriately set based on the light receiving amount to compensate for the fluctuation of the light emitting amount of the light emitting unit. As a result, it is possible to correctly determine whether or not the substrate exists at a specific position in the determination time zone excluding the absence time zone. Moreover, since the light receiving amount is obtained by using the absent time zone of the operating time zone without interrupting the operation of the substrate producing machine, the operation of the substrate producing machine is not hindered and the production efficiency is not lowered.

It is a front sectional view of the substrate transfer apparatus of the substrate production machine provided with the substrate detection apparatus of embodiment. It is a side sectional view of the substrate transfer apparatus. It is a block diagram which shows the control structure of the substrate detection apparatus of embodiment. It is a figure of the time chart explaining the operation of the time zone grasping part and setting part. It is an operation flow diagram of the board detection apparatus which includes the arithmetic processing and setting operation of a setting part. It is a figure of a bar graph which shows an example which the light-receiving amount this time changed within the permissible range as compared with the light-receiving amount when the latest threshold light amount was set. It is a figure of a bar graph which shows an example which the received light amount of this time changed beyond the permissible range as compared with the received light amount when the latest threshold light amount was set. It is a figure of the bar graph which shows the new threshold light amount obtained in FIG. 7.

Configuration and Operation of the Substrate Transfer Device 9 The substrate detection device 1 of the embodiment will be described with reference to FIGS. 1 to 8. First, the substrate transfer device 9 of the substrate production machine provided with the substrate detection device 1 will be described. FIG. 1 is a front sectional view of a substrate transfer device 9 of a substrate production machine provided with the substrate detection device 1 of the embodiment. Further, FIG. 2 is a side sectional view of the substrate transfer device 9. The transport direction of the substrate K is from the front side to the back side of the paper surface in FIG. 1 and from the left side to the right side in FIG. The board transfer device 9 is arranged on the upper surface of the machine base 99 of the electronic component mounting machine, which is a typical example of the board producing machine, and may be arranged on another type of board producing machine. Further, FIG. 3 is a block diagram showing a control configuration of the substrate detection device 1 of the embodiment. FIG. 3 also shows a control unit 2 of the substrate transfer device 9 which is a part of the substrate detection device 1.

The substrate transfer device 9 includes a pair of left and right guide rails 92, a conveyor belt 93, a drive motor 94, a clamp device 95, a control unit 2, and the like. As shown in FIG. 1, a pair of guide rails 92 are arranged above the pair of left and right support plates 91 that are erected. The distance between the pair of guide rails 92 is set according to the width of the substrate K. This separation distance may be adjusted variably. A belt guide 921 extending in the transport direction is provided inside the pair of guide rails 92 so as to face each other. An endless annular conveyor belt 93 is arranged so as to be guided to the upper surface of the belt guide 921 along each guide rail 92. The upper surface of the conveyor belt 93 serves as a transport path 3 for transporting the substrate K.

As shown in FIG. 2, the conveyor belt 93 is wound around a pair of front and rear transfer guide pulleys 922, a pair of front and rear return pulleys 923, a direction changing pulley 924, a drive pulley 925, and a tension applying pulley 926. The drive pulley 925 is supported so as to be integrally rotated with the spline shaft 927. The spline shaft 927 is rotationally driven by the drive motor 94. The tension applying pulley 926 applies tension to the conveyor belt 93 to prevent it from loosening. As a result, the conveyor belt 93 is rotary-driven, and the substrate K is placed on the upper surface of the conveyor belt 93 and conveyed.

The clamp device 95 is composed of a plurality of support pins 951, a pedestal 952, a fluid pressure cylinder 96, and the like. The number and arrangement of the plurality of support pins 951 are appropriately adjusted according to the type of the substrate K to be conveyed. The plurality of support pins 951 are erected on the upper surface of the rectangular plate-shaped pedestal 952. The pedestal 952 is supported and guided up and down by a plurality of pilot bars 953. The pedestal 952 is driven up and down by the fluid pressure cylinder 96.

As shown in FIG. 3, the control unit 2 has the functions of the transport control unit 21 and the positioning control unit 22. The transport control unit 21 controls the operation of the drive motor 94. The positioning control unit 22 controls the operation of the fluid pressure cylinder 96. As will be described later, the control unit 2 also serves as a part of the functions of the substrate detection device 1.

Next, the operation of the substrate transfer device 9 will be described. When the substrate K arrives at the inlet 31 of the transport path 3, the transport control unit 21 operates the drive motor 94. As a result, the conveyor belt 93 is rotated, and the substrate K is carried into the mounting execution position 32 at the substantially center of the transport path 3. Next, the positioning control unit 22 raises the fluid pressure cylinder 96. As a result, the pedestal 952 rises, and the support pin 951 pushes up the substrate K upward. The substrate K is positioned at a height KK between the presser portion 928 extending inward from the upper part of the guide rail 92 and the support pin 951.

Next, the electronic component mounting work is performed on the substrate K positioned at the height KK of the mounting execution position 32. When the mounting work is completed, the positioning control unit 22 lowers the fluid pressure cylinder 96. As a result, the pedestal 952 is lowered, and the substrate K is returned to the upper surface of the conveyor belt 93. Next, the transport control unit 21 operates the drive motor 94. As a result, the substrate K is carried out of the machine from the mounting implementation position 32 via the outlet 33 of the transport path 3. The substrate transfer device 9 can also carry out the substrate K and carry in another substrate K at the same time.

Configuration of the Substrate Detection Device 1 of the Embodiment The description of the substrate detection device 1 of the embodiment moves to the description. As shown in FIG. 3, the substrate detection device 1 of the embodiment includes a light projecting unit 4, a light receiving unit 5, a time zone grasping unit 23 and a setting unit 24 realized by the control function of the control unit 2. Has been done. The substrate detection device 1 detects the presence of the substrate K at a specific position on the transfer path 3 and reflects the detection result in the transfer control of the substrate K. In the present embodiment, the specific positions of the transport path 3 are set at the inlet 31 and the outlet 33, and are not limited thereto.

As shown in FIGS. 1 and 2, two sets of the light emitting unit 4 and the light receiving unit 5 are provided facing the inlet 31 and the outlet 33 of the transport path 3. The two light projecting units 4 are arranged on the guide rail 92 on the left side of FIG. The lighting and extinguishing of the light projecting unit 4 is controlled by the control unit 2. The light projecting unit 4 has a temperature dependence that the temperature fluctuates up and down immediately after the power is turned on or due to a temporary interruption of operation, and the amount of light projected fluctuates with time. The first light projecting unit 4 projects the detection light Ld toward the inlet 31. The second light projecting unit 4 projects the detection light Ld toward the outlet 33.

The two light receiving units 5 are arranged on the opposite side of the light emitting unit 4, that is, the guide rail 92 on the right side of FIG. 1 with the inlet 31 and the outlet 33 of the transport path 3 interposed therebetween. The first light receiving unit 5 receives the detection light Ld arriving from the first light projecting unit 4 through the inlet 31, and obtains the light receiving amount R. The second light receiving unit 5 receives the detection light Ld arriving from the second light projecting unit 4 through the outlet 33 and obtains the light receiving amount R. The detection light Ld is not limited to visible light, and may be invisible light such as infrared light.

The detected light Ld from the first light emitting unit 4 reaches the first light receiving unit 5 when the substrate K does not exist at the inlet 31. When the substrate K is present at the inlet 31, the detection light Ld from the first light projecting unit 4 is blocked at least partially by the substrate K and does not reach the first light receiving unit 5. That is, the light receiving amount R of the first light receiving unit 5 is reduced or eliminated. Similarly, the detected light Ld from the second light emitting unit 4 reaches the second light receiving unit 5 when the substrate K does not exist at the outlet 33. When the substrate K is present at the outlet 33, at least a part of the detected light Ld from the second light projecting unit 4 is blocked by the substrate K and does not reach the second light receiving unit 5. That is, the light receiving amount R of the second light receiving unit 5 is reduced or eliminated.

As shown in FIG. 3, the light receiving unit 5 includes a photoelectric conversion unit 51, a threshold light amount storage unit 52, a determination unit 53, and an output unit 54. The photoelectric conversion unit 51 photoelectrically converts the incident detection light Ld to obtain an electric signal representing the received light amount R. The threshold light amount storage unit 52 stores the threshold light amount S set by the setting unit 24. The determination unit 53 compares the amount of received light R with the amount of threshold light S, and sends the determination result J to the output unit 54. When the light receiving amount R is less than the threshold light amount S, the determination result J is set to "1" which means "the substrate K exists". Further, when the light receiving amount R is equal to or more than the threshold light amount S, the determination result J is set to "0" which means "the substrate K does not exist". The output unit 54 outputs the received light amount R and the determination result J to the control unit 2. The information of the received light amount R and the determination result J is shared inside the control unit 2.

Next, the functions of the time zone grasping unit 23 and the setting unit 24 in the control unit 2 will be described. The time zone grasping unit 23 and the setting unit 24 separately and independently control the two sets of the light emitting unit 4 and the light receiving unit 5. In the following, the description will be made mainly for the light emitting unit 4 and the light receiving unit 5 arranged on the inlet 31 side of the transport path 3. The time zone grasping unit 23 grasps the operating time zone in which the substrate production machine is operating by dividing it into an absent time zone Tn and a determination time zone Tj. The absence time zone Tn is a time zone in which the substrate K cannot exist at the inlet 31 of the transport path 3. Further, the determination time zone Tj is a time zone in which the absence time zone Tn is excluded from the operation time zone.

FIG. 4 is a diagram of a time chart illustrating the operations of the time zone grasping unit 23 and the setting unit 24. In FIG. 4, the horizontal axis represents the passage of time. The upper graph shows the determination result J of the determination unit 53, the middle graph shows the time zone of the arithmetic processing of the setting unit 24, and the lower graph shows the time zone of the setting operation of the setting unit 24. At time t1 in FIG. 4, the determination result J of the determination unit 53 changes from “1” to “0”. This means that the rear end of the first substrate K has passed through the inlet 31, that is, the time t1 is the time point at which the first substrate K is brought in. The time zone grasping unit 23 sets the time t1 as the start point of the absence time zone Tn.

After the time t1, the mounting operation on the first substrate K is performed at the mounting implementation position 32. The control unit 2 starts carrying in the second substrate K at time t4 after the mounting work is completed. Therefore, the substrate K cannot exist at the inlet 31 from the time t1 to the time t4. Therefore, the time zone grasping unit 23 sets the time t4 as the end point of the absence time zone Tn.

The end point of the absence time zone Tn can also be determined by another method. More specifically, the mounting work on the first substrate K requires a certain amount of mounting time. Therefore, the time zone grasping unit 23 can set a fixed time shorter than the mounting time, and set the end point of the absence time zone Tn when a fixed time has elapsed from the end of carrying in the first substrate K.

When the absence time zone Tn is grasped as described above, the determination time zone Tj is set after the time t4. At time t5 after the determination time zone Tj, the determination result J of the determination unit 53 changes from "0" to "1". This means that the tip of the second substrate K has been carried into the inlet 31. Therefore, the time t5 is the time when the second substrate K is started to be carried in. The transfer control unit 21 can accurately advance the transfer control of the second substrate K based on the carry-in start time.

As shown in the middle graph, the setting unit 24 starts the arithmetic processing at the time t2 after the absence time zone Tn. In the arithmetic processing of the setting unit 24, the determination of the necessity of resetting the threshold light amount S and the calculation of the threshold light amount S when the resetting is necessary are executed (details will be described later). The arithmetic processing of the setting unit 24 ends at time t3 before the end point (time t4) of the absence time zone Tn. At time t3, it is determined that the resetting of the threshold light amount S is unnecessary. Therefore, as shown in the lower graph, the setting unit 24 does not execute the setting operation.

The setting unit 24 repeatedly operates at time intervals of Td or more for a predetermined time. That is, the setting unit 24 starts the next calculation process at the time t7 after the predetermined time Td has elapsed from the time t2 when the current calculation process is started and after the absence time zone Tn. The absence time zone Tn at this time has the time t6 as the start point and the time t11 as the end point. 10 minutes can be exemplified as the predetermined time Td, and the present invention is not limited to this. It should be noted that the mounting work on the plurality of substrates K is performed between the time t2 and the time t6, and the absence time zone Tn and the determination time zone Tj occur alternately a plurality of times.

The next arithmetic processing of the setting unit 24 ends at time t8 before the end point (time t11) of the absence time zone Tn. At time t8, it is determined that the threshold light amount S needs to be reset. Therefore, as shown in the lower graph, the setting unit 24 executes the setting operation from the time t9. The setting operation of the setting unit 24 ends at time t10 before the end point (time t11) of the absence time zone Tn.

Operation and operation of the substrate detection device 1 of the embodiment Next, the operation and operation of the substrate detection device 1 of the embodiment will be described. FIG. 5 is an operation flow diagram of the substrate detection device 1 including the arithmetic processing and the setting operation of the setting unit 24. This operation flow diagram is executed in parallel with the production operation during the operation time zone in which the board production machine is operating. Initial setting is performed in step S1 of FIG. More specifically, the light receiving amount R is manually measured between the end of the setup change corresponding to the type of the substrate K to be produced next and the time when the substrate K is carried in. Then, the initial values of the received light amount R and the threshold light amount S are set based on the result of the manual measurement. Further, the allowable range D and the coefficient A, which will be described later, are automatically set based on the information on the width dimension and the thickness of the substrate K to be produced next.

In the next step S2, the light receiving unit 5 obtains the light receiving amount R, and outputs the light receiving amount R and the determination result J to the control unit 2. In the next step S3, the control unit 2 refers to the grasping result of the time zone grasping unit 23, advances the execution of the operation flow to step S4 in the case of the absence time zone Tn, and proceeds to the operation flow in the case of the determination time zone Tj. To step S11.

In step S4, the setting unit 24 determines whether or not a predetermined time Td has elapsed since the previous operation. If the substrate detection device 1 has just started and there is no previous operation, the setting unit 24 determines whether or not Td has elapsed for a predetermined time from the start. The setting unit 24 returns the execution of the operation flow to step S2 when the predetermined time Td has not elapsed, and proceeds to the execution of the operation flow in step S5 when the predetermined time Td has elapsed.

In step S5, the setting unit 24 investigates whether or not it is an abnormal time. In this embodiment, two types of abnormalities are considered. The first abnormality is a case where the current light receiving amount R changes beyond the abnormality determination range as compared with the previous light receiving amount R. In this case, for example, it is assumed that a foreign substance accidentally enters the inlet 31 of the transport path 3 to block the detection light Ld. The second abnormality is a case where the transfer of the substrate K is hindered in the transfer path 3. At the time of two kinds of abnormalities, there is doubt about the reliability of the obtained light receiving amount R. Therefore, the setting unit 24 returns the execution of the operation flow to step S2 if it is abnormal, and proceeds to the execution of the operation flow to step S6 if it is not abnormal.

In step S6, the setting unit 24 determines whether or not the current light receiving amount R has changed beyond the permissible range D as compared with the past received light amount Rpst when the newest threshold light amount S is set. The light receiving amount R this time is the amount obtained in the absence time zone Tn, in other words, the amount obtained in the state where the substrate K does not exist at the inlet 31 of the transport path 3. The latest threshold light amount S is the one set in the threshold light amount storage unit 52 in step S8 before the previous time. In the initial stage when the substrate detection device 1 is started, the newest threshold light amount S and the past received light amount R are the initial values initially set in step S1. The permissible range D can be set to, for example, ± 10% of the past received light amount Rpst, and is not limited to this. The setting unit 24 returns the execution of the operation flow to step S2 when the received light amount R changes within the allowable range D, that is, does not reset the threshold light amount S. Further, when the light receiving amount R this time changes beyond the permissible range D, the setting unit 24 advances the execution of the operation flow to step S7.

In step S7, the setting unit 24 multiplies the light receiving amount R this time by a coefficient A less than 1, and obtains a new threshold light amount Snew. The coefficient A is appropriately set based on the width dimension and thickness of the substrate K that blocks the detection light Ld. 50% can be exemplified as the coefficient A, and the coefficient A is not limited to this. Instead of multiplying by the coefficient A, a certain amount may be subtracted from the received light amount R this time to obtain a new threshold light amount Snew. In the next step S8, the setting unit 24 sets a new threshold light amount Snew in the threshold light amount storage unit 52. The threshold light amount storage unit 52 stores a new threshold light amount Snew in the memory in addition to the original threshold light amount S, and leaves a change history. After that, the setting unit 24 returns the execution of the operation flow to step S2.

Here, the operation flow of step S6 and step S7 will be described with reference to specific examples. FIG. 6 is a bar graph showing an example in which the light receiving amount R this time is changed within the allowable range D as compared with the light receiving amount Rpst when the newest threshold light amount S is set. Further, FIG. 7 is a bar graph showing an example in which the received light amount Rnow changed beyond the permissible range D as compared with the received light amount Rpst when the newest threshold light amount S was set. Further, FIG. 8 is a bar graph showing the new threshold light amount Snew obtained in FIG. 7.

As illustrated in FIG. 6, the threshold light amount S is set by multiplying the past received light amount Rpst by a coefficient A less than 1. When the operating state of the light projecting unit 4 is stable and the temperature change is small, the light receiving amount R this time does not deviate from the allowable range D even if it fluctuates slightly statistically. Therefore, in this case, it is not necessary to reset the threshold light amount S.

However, immediately after the power of the light projecting unit 4 is turned on or when the operation is temporarily interrupted, the temperature change becomes large and the light projecting amount changes. Along with this, as illustrated in FIG. 7, the received light amount Rnow may change beyond the permissible range D. In this case, if the threshold light amount S is not reset, there is a risk of an erroneous determination result J. Therefore, in step S7, the setting unit 24 obtains a new threshold light amount Snew by multiplying the received light amount Rnow this time by the coefficient A. The new threshold light amount Snew has a difference ΔS with respect to the original threshold light amount S.

As a result, as shown in FIG. 8, the newest threshold light amount Snew is obtained, and this is set by the received light amount Rnow this time. Then, in the next step S6, the setting unit 24 determines whether or not the light receiving amount Rnext obtained next time is within the allowable range D of the light receiving amount Rnow this time. In addition, the determination unit 53 determines the presence of the substrate K by comparing the magnitude of the light receiving amount Rnext obtained next time with the new threshold light amount Snew. In this way, the temperature dependence of the light projecting unit 4 can be compensated.

Returning to the operation flow of FIG. 5, in the case of the determination time zone Tj and after step S11, the control unit 2 shares a part of the functions of the determination unit 53. That is, the control unit 2 determines whether or not the substrate K exists at the inlet 31 of the transport path 3 according to the determination result J during the determination time zone Tj. More specifically, in step S11, the control unit 2 investigates the content of the determination result J. In step S12 when the determination result J = "1", the control unit 2 determines that the substrate K exists at the inlet 31. Further, in step S13 when the determination result J = "0", the control unit 2 determines that the substrate K does not exist at the inlet 31. The control unit 2 determines that the substrate K does not exist at the inlet 31 during the absence time zone Tn regardless of the determination result J.

After step S12 and step S13, the control unit 2 returns the execution of the operation flow to step S2. This completes one cycle of the operation flow. After that, steps S2 and subsequent steps are repeatedly executed at predetermined control cycle intervals. By sequentially determining the presence of the substrate K in steps S12 and S13, the timing at which the front end and the rear end of the substrate K pass through the inlet 31 of the transport path 3 becomes clear. The transfer control unit 21 can accurately advance the transfer control of the substrate K based on these timings.

The operation of the substrate detection device 1 described with reference to FIGS. 5 to 8 is the same for the light projecting unit 4 and the light receiving unit 5 arranged on the outlet 33 side of the transport path 3. However, the time zone grasping unit 23 sets the start point of the absence time zone Tn at the end point of carrying out the third substrate K in which the determination result J of the light receiving unit 5 on the outlet 33 side changes from “1” to “0”. Then, the time zone grasping unit 23 sets the time when the fourth substrate K is started to be carried out after the mounting work is completed as the end point of the absence time zone Tn. Alternatively, the time zone grasping unit 23 may set a fixed time shorter than the mounting time, and set the end point of the absence time zone Tn when a fixed time has elapsed from the end of carrying out the third substrate K.

Aspects and Effects of the Substrate Detection Device 1 of the Embodiment The substrate detection device 1 of the embodiment is arranged so as to face a specific position (inlet 31, outlet 33) of a transport path 3 provided in the substrate production machine for transporting the substrate K. The substrate production machine operates: a light projecting unit 4 that projects the detection light Ld toward a specific position, a light receiving unit 5 that is arranged facing the specific position and receives the detected light Ld to obtain the light receiving amount R. A time zone grasping unit that grasps the absent time zone Tn that is a part of the operating time zone and the substrate K cannot exist at a specific position, and the determination time zone Tj excluding the absence time zone Tn from the operating time zone. 23, the setting unit 24 for setting the threshold light amount S for determining whether or not the substrate K exists at a specific position based on the light receiving amount R obtained in the absence time zone Tn, and the determination time zone Tj. The light receiving amount R is compared with the threshold light amount S, and a determination unit 53 and a control unit 2 for determining whether or not the substrate K exists at a specific position are provided.

According to the substrate detection device 1 of the embodiment, the light receiving unit 5 is in the absence time zone Tn, which is a part of the operating time zone in which the substrate production machine is operating and the substrate K cannot exist at a specific position of the transport path 3. The amount of light received R can be obtained. Since the obtained light receiving amount R is the light receiving amount R when it is known that the substrate K does not exist, the threshold light amount S is appropriately set based on the light receiving amount R, and the light emitting amount of the light projecting unit 4 is set. Fluctuations can be compensated. As a result, it is possible to correctly determine whether or not the substrate K exists at a specific position in the determination time zone Tj excluding the absence time zone Tn. Moreover, since the light receiving amount R is obtained by using the absence time zone Tn in the operating time zone without interrupting the operation of the substrate producing machine, the operation of the substrate producing machine is not hindered and the production efficiency is not lowered. ..

Further, the light receiving unit 5 is arranged on the opposite side of the light projecting unit 4 with the specific positions (inlet 31, outlet 33) interposed therebetween, and the detection light Ld is transmitted to the light receiving unit 5 when the substrate K does not exist at the specific position. When it reaches and the substrate K is present at a specific position, at least a part of the substrate K is blocked by the substrate K and the light receiving portion 5 is not reached. According to this, in the substrate detection device 1 of the type in which the detection light Ld is shielded by the substrate K, the effect of not lowering the production efficiency can be obtained.

Further, the setting unit 24 obtains the threshold light amount Snew by multiplying the light receiving amount Rnow obtained in the absence time zone Tn by a coefficient A less than 1, and the determination unit 53 obtains the light receiving amount Rnext obtained in the judgment time zone Tj. When is less than the threshold light amount Snew, it is determined that the substrate K exists, and when the light receiving amount Rnext obtained in the determination time zone Tj is equal to or more than the threshold light amount Snew, it is determined that the substrate K does not exist. According to this, the coefficient A can be appropriately set to obtain an appropriate threshold light amount Snew, and the existence of the substrate K can be determined with high accuracy.

Further, the setting unit 24 repeatedly operates at time intervals of Td or more for a predetermined time, and the light receiving amount Rnow this time exceeds the allowable range D as compared with the light receiving amount Rpst when the newest threshold light amount S is set. When the amount of light changes, the threshold light amount Snew is reset, and when the amount of received light R this time changes within the allowable range D, the threshold light amount S is not reset.

According to this, when the light projecting amount changes due to the temperature dependence of the light projecting unit 4 and the light receiving amount R of the light receiving unit 5 in the absence time zone Tn changes significantly, the threshold light amount Snew can be reset. Therefore, the threshold light amount Snew is variably adjusted so as to compensate for the temperature dependence of the light projecting unit 4, and the presence of the substrate K can be determined with extremely high accuracy. Further, when the change in the light receiving amount R of the light receiving unit 5 in the absence time zone Tn is small, unnecessary resetting operation is not performed. Therefore, control redundancy can be avoided, and the memory capacity of the threshold light amount storage unit 52 can be saved.

Further, the specific position is the inlet 31 of the transport path 3, and in the absence time zone Tn, the determination result of the determination unit 53 changes from "the substrate exists" to "the substrate does not exist" of the first substrate K. It is a time zone from the end of carry-in (time t1) to the time t4 when the carry-in of the second substrate K is started, or a time zone from the end of carry-in until a certain time elapses. According to this, the presence of the substrate K can be determined with high accuracy at the inlet 31 of the transport path 3. Therefore, it is possible to detect the carry-in of the tip of the second substrate K and accurately proceed with the subsequent transport control.

Further, the specific position is the outlet 33 of the transport path 3, and in the absence time zone Tn, the determination result of the determination unit 53 changes from "the substrate exists" to "the substrate does not exist" of the third substrate K. It is a time zone from the end of unloading to the start of unloading of the fourth substrate K, or a time zone from the end of unloading until a certain time elapses. According to this, the existence of the substrate K can be determined with high accuracy at the outlet 33 of the transport path 3.

Further, the setting unit 24 repeatedly operates at time intervals of Td or more for a predetermined time, and resets the threshold light amount S when the light receiving amount of this time changes beyond the abnormality determination range as compared with the previous light receiving amount. Do not do. According to this, when there is doubt about the reliability of the obtained light receiving amount R, the threshold light amount S is not reset, so that the operation reliability is high.

Further, the setting unit 24 repeatedly operates at time intervals of Td or more for a predetermined time, and does not reset the threshold light amount S when an abnormality occurs in the transfer of the substrate K on the transfer path 3. According to this, when there is doubt about the reliability of the obtained light receiving amount R, the threshold light amount S is not reset, so that the operation reliability is high.

Application and Modification of the Embodiment The light projecting unit 4 and the light receiving unit 5 may be arranged only at one of the inlet 31 and the outlet 33 of the transport path 3, or a set around the mounting implementation position 32. May be disposed. Further, the threshold light amount storage unit 52 and the determination unit 53 may be provided on the side of the control unit 2, and the output unit 54 may be configured to output only the received light amount R. Further, in the present embodiment, the detection light Ld is projected in the width direction of the substrate K, but the detection light Ld may be projected in the thickness direction of the substrate K.

Further, in the present embodiment, the detection light Ld is shielded by the substrate K, but the detection light Ld may be reflected by the substrate K. That is, a light projecting unit that faces a specific position of a transport path provided in the board production apparatus for transporting the substrate and projects detection light toward the specific position and a light projecting unit that faces the specific position. A light receiving unit that receives the detected light to obtain the amount of received light, a part of the operating time zone in which the substrate production apparatus is operating, an absent time zone in which the substrate cannot be present at the specific position, and the operation. A time zone grasping unit that grasps a determination time zone excluding the absence time zone from the time zone, and a threshold light amount that determines the presence or absence of the substrate at the specific position based on the received light amount obtained during the absence time zone. The light receiving unit includes a setting unit for setting the above and a determination unit for determining the presence or absence of the substrate at the specific position by comparing the light receiving amount obtained in the determination time zone with the threshold light amount. Arranged side by side with the light projecting portion, the detected light does not reach the light receiving portion when the substrate is not present at the specific position, and at least a part thereof is reflected by the substrate when the substrate is present at the specific position. You may adopt the aspect that the light receiving part is reached. The present invention has various other applications and modifications.

1: Board detection device 2: Control unit 23: Time zone grasping unit 24: Setting unit 3: Transport path 31: Inlet 32: Mounting implementation position 33: Exit 4: Light emitting unit 5: Light receiving unit 51: Photoelectric conversion unit 52: Threshold light storage unit 53: Judgment unit 54: Output unit 9: Substrate carrier K: Substrate Ld: Detection light R: Received amount Rpst: Past received light amount Rnow: Current received light amount S: Threshold light amount Snew: New threshold light amount J : Judgment result Tn: Absence time zone Tj: Judgment time zone Td: Predetermined time D: Allowable range A: Coefficient

Claims (7)

A transfer path for transporting a substrate, which is arranged facing a specific position of the transfer path provided in a substrate production machine that works on the substrate, and emits detection light toward the specific position. Department and
A light receiving unit that is arranged facing the specific position and receives the detected light to obtain the amount of received light.
A part of the operating time zone in which the substrate production machine is operating, an absent time zone in which the substrate cannot exist at the specific position, and a determination time zone in which the absent time zone is excluded from the operating time zone. Time zone grasping part to grasp and
A setting unit that sets a threshold light amount for determining whether or not the substrate exists at the specific position based on the received light amount obtained in the absence time zone, and does not set the threshold light amount in the determination time zone. ,
The amount of received light obtained in the determination time zone is compared with the threshold light amount to determine whether or not the substrate exists at the specific position, and whether or not the substrate exists in the absence time zone. Equipped with a judgment unit that does not judge
The specific position is the entrance of the transport path.
The absent time zone is
The predetermined length required for the work to the first substrate from the time when the determination result of the determination unit changes from "the substrate exists" to "the substrate does not exist" from the end of carrying in the first substrate. Time zone until the known work time elapses , or
From the carry-in at the end, which is the time period until the end of the short for a certain period of time than during the time of the operation industry,
Board detector. A transfer path for transporting a substrate, which is arranged facing a specific position of the transfer path provided in a substrate production machine that works on the substrate, and emits detection light toward the specific position. Department and
A light receiving unit that is arranged facing the specific position and receives the detected light to obtain the amount of received light.
A part of the operating time zone in which the substrate production machine is operating, an absent time zone in which the substrate cannot exist at the specific position, and a determination time zone in which the absent time zone is excluded from the operating time zone. Time zone grasping part to grasp and
A setting unit that sets a threshold light amount for determining whether or not the substrate exists at the specific position based on the received light amount obtained in the absence time zone, and does not set the threshold light amount in the determination time zone. ,
The amount of received light obtained in the determination time zone is compared with the threshold light amount to determine whether or not the substrate exists at the specific position, and whether or not the substrate exists in the absence time zone. Equipped with a judgment unit that does not judge
The specific position is the exit of the transport path.
The absent time zone is
A predetermined length required for the work on the fourth substrate from the time when the determination result of the determination unit changes from "the substrate exists" to "the substrate does not exist" from the end of carrying out the third substrate. Time zone until the known work time elapses , or
From the carry-out at the end, which is the time period until the end of the short for a certain period of time than during the time of the operation industry,
Board detector. The light receiving unit is arranged on the opposite side of the light projecting unit with the specific position in between.
The detection light is
When the substrate does not exist at the specific position, the light receiving portion is reached and the substrate is reached.
When the substrate is present at the specific position, at least a part of the substrate is blocked by the substrate and does not reach the light receiving portion.
The substrate detection device according to claim 1 or 2. The setting unit obtains the threshold light amount by multiplying the received light amount obtained during the absence time zone by a coefficient of less than 1.
The determination unit determines that the substrate exists when the received light amount obtained during the determination time zone is less than the threshold light amount, and when the received light amount obtained during the determination time zone is equal to or greater than the threshold light amount. Judges that the substrate does not exist in
The substrate detection device according to claim 3. The setting unit
It operates repeatedly at time intervals of a predetermined time or longer,
Compared with the received light amount when the latest threshold light amount is set, the threshold light amount is reset when the received light amount changes beyond the allowable range, and the received light amount this time is the allowable range. Do not reset the threshold light intensity when it changes within the range of
The substrate detection device according to any one of claims 1 to 4. The setting unit repeatedly operates at time intervals of a predetermined time or longer, and resets the threshold light amount when the light receiving amount of this time changes beyond the abnormality determination range as compared with the previous light receiving amount. The substrate detection device according to any one of claims 1 to 5. Any one of claims 1 to 6, wherein the setting unit repeatedly operates at time intervals of a predetermined time or longer, and does not reset the threshold light amount when an abnormality occurs in the transfer of the substrate in the transfer path. The substrate detection device according to one item.

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