WO2022185428A1

WO2022185428A1 - Substrate transfer apparatus and substrate transfer method

Info

Publication number: WO2022185428A1
Application number: PCT/JP2021/008069
Authority: WO
Inventors: 太郎伊藤
Original assignee: 株式会社Fuji
Priority date: 2021-03-03
Filing date: 2021-03-03
Publication date: 2022-09-09
Also published as: CN116762485A; JP7432058B2; DE112021007189T5; JPWO2022185428A1

Abstract

This substrate transfer apparatus is provided with a transfer unit that transfers a substrate from an inlet end of a transfer path to a predetermined stopping position, a substrate passing sensor that projects a detection light toward the substrate passing through a prescribed position closer to the inlet end side of the transfer path than the stopping position and detects the presence of the substrate at the prescribed position on the basis of a passing amount or a reflected amount of the detection light, a setting unit that, when the transfer unit transfers the substrate, sets a future transfer distance for transferring the substrate to the stopping position at a time when the detection result of the substrate passing sensor goes from "no substrate", to "substrate detected", and then to "no substrate", a monitoring unit that monitors whether or not the detection result once again changes to "substrate detected" until the substrate reaches the stopping position, and a resetting unit that, when the detection result once again changes to "substrate detected", at the time when the detection result then changes to "no substrate", resets the previously set transfer distance and sets the future transfer distance again.

Description

Substrate transfer device and substrate transfer method

The present specification relates to a substrate transport apparatus for transporting a substrate to a predetermined stop position on a transport path, and a substrate transport method.

The technology of mass-producing board products by performing board-to-board work on boards with printed wiring is widespread. Furthermore, it is common to configure a work line for board by arranging a plurality of work machines for work on board. Generally, a board-oriented work machine includes a board transfer device. The substrate transport device transports the substrate loaded from the upstream side of the line to a predetermined stop position on the transport path, and transports the substrate after the substrate work is performed at the stop position to the downstream side of the line. Many substrate transfer apparatuses are equipped with a substrate passage sensor that detects the position of the substrate to be transferred. A technical example related to this type of substrate transfer apparatus is disclosed in Japanese Unexamined Patent Application Publication No. 2002-200013.

The substrate detection sensor disclosed in Patent Document 1 compares the level of the received light signal with a first threshold value when determining "no substrate", and determines "with substrate" when the level is equal to or lower than the first threshold. Further, the board detection sensor compares the level of the received light signal with a second threshold larger than the first threshold when determining that "there is a board", and determines that the level is equal to or higher than the second threshold as "there is no board". According to this, even if the board moves from a predetermined position due to vertical vibration after the determination of "board present", the determination of "board present" can be maintained, and erroneous determinations with respect to positional fluctuations of the board can be reduced. It is

JP 2017-183630 A

By the way, in conventional technologies including the substrate detection sensor of Patent Document 1, detection light is projected toward the substrate, and the presence or absence of the substrate is detected based on changes in the amount of passage or reflection of the detection light. However, in a cracked substrate having a gap, the passing amount of detection light temporarily increases or the amount of reflection decreases in the gap, making it difficult to accurately detect the presence or absence of the substrate. In addition, a substrate having deformation such as warpage may cause an erroneous determination of the presence or absence of the substrate because the area that blocks the detection light may change as the substrate is transported.

As a countermeasure for the above problem, conventionally, a timer was set to avoid the effects of temporary fluctuations in the amount of detected light passing through or reflected. In other words, by ignoring the temporary variation if the duration of the variation is less than the timer time, an erroneous determination due to the void portion of the cracked substrate, the warped portion of the substrate, or the like is avoided. Also, depending on the setting of the timer, the detection of the trailing edge of the substrate is delayed by the distance obtained by multiplying the timer time by the transport speed of the substrate. distance adjustment).

Even with such timer settings and transport distance adjustments, it was difficult to eliminate errors in board-to-board work machine stoppages due to transport abnormalities and reduced board stop position accuracy. In addition, setting the timer and adjusting the transport distance are different for each type of board and must be done individually for each of the multiple work machines that make up the work line for the board, thus requiring a great deal of time and effort on the part of the operator. was bothering me.

Therefore, the present specification aims to provide a board transfer apparatus and a board transfer method that can reduce the error stoppage of a work machine for a board due to a transfer abnormality and the decrease in accuracy of the stop position of the board. It should be an issue to be addressed.

The present specification includes a transport unit that transports a substrate from a loading end of a transport path to a predetermined stop position, and a detection light directed toward the substrate passing through a specified position on the loading end side of the transport path relative to the stop position. and a substrate passage sensor that detects the presence or absence of the substrate at the specified position based on the amount of passage or reflection of the detection light; a setting unit for setting a future transport distance for transporting the substrate to the stop position when the detection result changes from "no substrate" through "substrate present" to "no substrate"; a monitoring unit for monitoring whether or not the detection result changes to "substrate present" again until reaching , and if the detection result changes to "substrate present" again, then the detection result changes to "substrate absent" and a resetting unit that resets the set transport distance and resets the future transport distance when the transport distance changes to .

Further, in the present specification, a transport unit that transports a substrate from the loading end of a transport path to a predetermined stop position, and a substrate that passes through a specified position on the loading end side of the transport path from the stop position. A substrate passage sensor that projects detection light and detects the presence or absence of the substrate at the specified position based on the amount of passage or reflection of the detection light, and controls the transport unit based on the detection result of the substrate passage sensor. and a control unit for transporting the substrate, the control unit changes the detection result from “no substrate” to “no substrate” via “substrate present” when the transport unit transports the substrate. At that point, a future transport distance for transporting the substrate to the stop position is set, and it is monitored whether the detection result changes to "substrate presence" again until the substrate reaches the stop position. , when the detection result changes to "substrate present" again, and when the detection result subsequently changes to "substrate absent", the set transport distance is reset and the future transport distance is set again. discloses a substrate transfer method.

In the substrate transfer apparatus and the substrate transfer method disclosed in this specification, when the detection result of the substrate passing sensor changes from "no substrate" to "no substrate" via "substrate present", it is determined that the substrate is at the rear end. to set the future transport distance. Then, when the detection result changes to "with board" again, when the detection result changes to "without board" after that, it is determined to be the trailing edge of the board, and the set transport distance is reset and future Reset the transport distance. According to this, even if the trailing edge is erroneously determined due to the presence of a gap in the cracked substrate or the warped portion of the substrate, when the true trailing edge of the substrate is determined to be corrected after that, the transport distance from now on will be restarted. set. Therefore, it is possible to improve the detection accuracy of the trailing edge of the board more than before, and as a result, it is possible to reduce the error stop of the work machine for the board due to the transfer abnormality and the decrease of the precision of the stop position of the board more than before. .

It is a top view which shows the whole structure of the components mounting machine to which the board|substrate conveying apparatus of 1st Embodiment is applied. 1 is a plan view schematically showing a substrate transfer device according to a first embodiment; FIG. 1 is a side view schematically showing a substrate transfer device according to a first embodiment; FIG. 3 is a block diagram showing a control configuration of the substrate transfer device; FIG. It is a figure of the operation|movement flow explaining operation|movement of a board|substrate conveying apparatus. FIG. 10 is a plan view showing a state in which the rear end of a normal substrate reaches a specified position (carry-in end) of the transport path; FIG. 11 is a plan view showing a state in which a normal substrate reaches a stop position on the transport path and stops; FIG. 4 is a plan view showing a state before starting a transport operation of a broken substrate; FIG. 10 is a plan view showing a state in which the trailing edge of the small substrate piece on the front side of the broken substrate has reached a specified position (carry-in end) of the transport path; FIG. 10 is a plan view showing a state in which the front edge of the small piece substrate on the rear side of the broken substrate has reached a specified position (carry-in end) of the transport path; FIG. 10 is a plan view showing a state in which the rear end of the cracked substrate has reached a specified position (carry-in end) of the transport path; FIG. 4 is a plan view showing a state in which a broken substrate has reached a stop position on the transport path and stopped. It is a top view which shows typically the board|substrate conveying apparatus of 2nd Embodiment. FIG. 11 is a side view schematically showing a state in the middle of transporting a warped substrate in the second embodiment. It is a front view which shows typically the board|substrate conveying apparatus of 3rd Embodiment.

1. Overall Configuration of Component Mounting Machine 1 First, the overall configuration of a component mounting machine 1 to which the board transfer device 2 of the first embodiment is applied will be described with reference to FIG. The component mounting machine 1 performs a mounting operation of mounting components on the substrate K. FIG. A solder printing machine or the like is arranged on the upstream side of the component mounting machine 1, and a substrate inspection machine or the like is arranged on the downstream side to constitute a work line for substrates. The direction from the left side to the right side of FIG. 1 is the X-axis direction for transporting the substrate K, and the direction from the bottom side (front side) to the top side (rear side) of the page is the Y-axis direction. The component mounting machine 1 is configured by assembling a board conveying device 2 , a component supply device 3 , a component transfer device 4 , a component recognition camera 49 , a control device 5 (see FIG. 4 ), and the like on a base 10 .

The board transfer device 2 has a pair of guide rails 21 . The pair of guide rails 21 extend in the X-axis direction on the base 10 and are arranged parallel to each other and spaced apart in the Y-axis direction. The separation distance between the pair of guide rails 21 can be adjusted according to the width of the substrate K. As shown in FIG. A pair of guide rails 21 and a space therebetween constitute a transport path for the substrate K. As shown in FIG. The substrate conveying device 2 conveys the horizontally positioned substrate K from the carry-in end 22 of the guide rail 21 (conveyance path) to a predetermined stop position PS (see FIG. 2). A positioning mechanism (not shown) provided below the stop position PS positions and releases the substrate K. As shown in FIG. The details of the substrate transfer device 2 will be described later.

The component supply device 3 is composed of a plurality of feeders 31 arranged side by side in the X-axis direction. Each feeder 31 sends out a carrier tape in which a large number of components are stored in a line toward a supply position 32 on the leading end side. A carrier tape provides a pickable supply of parts at a supply position 32 .

The component transfer device 4 is composed of a Y-axis moving body 41, an X-axis moving body 42, a mounting head 43, an automatic tool 44, a suction nozzle 45, a board recognition camera 46, a side view camera 47, and the like. The Y-axis moving body 41 is driven by a linear motion mechanism to move in the Y-axis direction. The X-axis moving body 42 is mounted on the Y-axis moving body 41 and driven by the linear motion mechanism to move in the X-axis direction. The mounting head 43 is attached to a clamping mechanism (not shown) provided on the front surface of the X-axis moving body 42 and moves in two horizontal directions together with the X-axis moving body 42 .

An automatic tool 44 is rotatably provided below the mounting head 43 . A plurality (12 in the example of FIG. 1) of suction nozzles 45 are exchangeably held below the automatic tool 44 . The suction nozzle 45 is driven by an elevation drive mechanism (not shown) to ascend and descend, and is selectively supplied with negative or positive pressure air from an air supply mechanism (not shown). The suction nozzle 45 sucks and holds the component from the supply position 32 of the component supply device 3 and mounts it on the substrate K. FIG. The mounting head 43, the automatic tool 44, and the suction nozzle 45 may be replaced by an operator or automatically. In the case of automatic replacement, a replacement station is provided on the upper surface of the base 10, and replacement equipment is prepared.

The board recognition camera 46 is provided on the X-axis moving body 42 along with the mounting head 43 . The board recognition camera 46 is arranged with its optical axis directed downward, and images the position reference mark attached to the board K from above. The acquired image data is image-processed, and the stop position of the substrate K is obtained accurately. A side-view camera 47 is provided on the front side of the autotool 44 below the mounting head 43 . The side-view camera 47 captures and recognizes the component held by the suction nozzle 45 together with the lower part of the suction nozzle 45 from the side. As the board recognition camera 46 and the side view camera 47, a digital imaging device having an imaging device such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) can be exemplified.

The component recognition camera 49 is provided on the base 10 between the substrate transport device 2 and the component supply device 3. The component recognition camera 49 is arranged so that the optical axis faces upward. The component recognition camera 49 captures and recognizes the component held by the suction nozzle 45 from below while the mounting head 43 is moving from the component supply device 3 to the board K. As the component recognition camera 49, a digital imaging device having an imaging element such as a CCD or CMOS can be exemplified.

The control device 5 is assembled to the base 10, and the position at which it is arranged is not particularly limited. The control device 5 is configured using a computer device having a CPU and operated by software. Note that the control device 5 may be configured by distributing a plurality of CPUs inside the machine and connecting them for communication. Based on the job data for each type of board K, the control device 5 controls the board conveying device 2, the component supply device 3, the component transfer device 4, and the component recognition camera 49 to proceed with the component mounting work. . The job data is data describing detailed procedures and implementation methods of the mounting work.

2. Configuration of Substrate Transfer Apparatus 2 of First Embodiment Description will be made on the substrate transfer apparatus 2 of the first embodiment. The board transfer device 2 includes a transfer section 6, a board passage sensor 7, and a transfer control section 8 in addition to the pair of guide rails 21 described above. As shown in FIG. 2, a predetermined stop position PS for stopping the substrate K is set at the center of the pair of guide rails 21 (transport path) in the transport direction (X-axis direction). As shown in FIG. 3, the transport section 6 has a conveyor belt 61, two support pulleys (62, 63), a tension pulley 64 and a drive pulley 65 which are individually provided for each of the guide rails 21. . Further, the transport section 6 has a drive motor 66 that is commonly provided for the two drive pulleys 65 .

The conveyor belt 61 is formed in an endless loop using a flexible strip-shaped member. The conveyor belt 61 is fitted into grooves formed in the guide rails 21 and held rotatably (see FIG. 15). The substrate K is placed horizontally across the top surfaces of the two conveyor belts 61 . The support pulley 62 is rotatably provided at the carry-in end 22 of the guide rail 21 . The support pulley 63 is rotatably provided at the unloading end 23 of the guide rail 21 . Two support pulleys (62, 63) support the conveyor belt 61 for rotation.

The tension pulley 64 is rotatably provided below the support pulley 62 on the carry-in end 22 side. The tension pulley 64 is urged by an unillustrated urging mechanism to apply tension to the conveyor belt 61 to prevent slackening. A drive pulley 65 is provided below the support pulley 63 on the delivery end 23 side and engages the conveyor belt 61 . The conveyor belt 61 is supported by the four pulleys described above and rotates clockwise in FIG. The drive motor 66 rotates the two drive pulleys 65 at a constant speed via a transmission mechanism (not shown).

Thereby, each of the two drive pulleys 65 rotates the conveyor belt 61 respectively. The two conveyor belts 61 transport the placed substrate K. As shown in FIG. As the drive motor 66, a pulse motor, a stepping motor, or the like with good controllability is used. Therefore, the transport speed and transport distance of the substrate K can be freely adjusted, and the accurate transport distance of the substrate K can be obtained.

The substrate passing sensor 7 detects the presence or absence of the substrate K at the specified position. In the first embodiment, the specified position is set to coincide with the carry-in end 22 of the guide rail 21 (conveyance path). The specified position is not limited to this, and may be a position further toward the stop position PS than the carry-in end 22, and should be a position closer to the carry-in end 22 than the stop position PS. In the first embodiment, the substrate passage sensor 7 employs a vertical passage type that projects the detection light DL in the vertical direction and detects the presence or absence of the substrate K based on the amount of passage of the detection light DL.

The board passage sensor 7 is composed of a light projecting section 71, a light receiving section 72, and a determination section 73 (see FIG. 4). As shown in FIG. 3 , the light projecting section 71 is arranged above the carry-in end 22 . The light projecting unit 71 projects vertically downward detection light DL toward the horizontal substrate K passing through the carry-in end 22 . The light projecting part 71 is maintained in a lighting state throughout the operating time period of the component mounting machine 1 .

On the other hand, the light receiving section 72 is arranged on the opposite side of the light projecting section 71 with the substrate K therebetween, in other words, below the carry-in end 22 . The light receiving section 72 detects the passing amount of the detection light DL. The passing amount of the detection light DL is large when there is no substrate K at the carry-in end 22, and decreases or disappears when the substrate K is present. Note that the light projecting unit 71 and the light receiving unit 72 may be arranged upside down, and the light projecting unit 71 may project the vertically upward detection light DL.

The determination unit 73 receives information on the amount of passage of the detection light DL from the light receiving unit 72 . The determination unit 73 determines that there is no substrate when the passing amount is equal to or greater than a predetermined threshold, and determines that there is a substrate when the passing amount is less than the threshold. The predetermined threshold is determined in advance in consideration of various conditions. These conditions include the performance of the light projecting section 71 and the light receiving section 72, changes in performance over time, tolerance of arrangement, light transmittance depending on the material and thickness of the substrate K, and the like. The determination section 73 outputs the determination result to the transport control section 8 . The determination result of the determination unit 73 corresponds to the detection result of the substrate passing sensor 7 . Note that the determination section 73 may be provided integrally with the light receiving section 72 or may be provided within the transport control section 8 .

3. Configuration of Control of Substrate Transfer Apparatus 2 Next, the configuration of control of the substrate transfer apparatus 2 will be described with reference to FIG. The transport control unit 8 is configured using a computer device. The transport control unit 8 controls the transport of the substrate K based on a command from the higher-level control device 5 connected for communication, and reports the control status to the control device 5 . The transport control unit 8 executes the substrate transport method of the embodiment as described in detail below.

The transport control unit 8 receives the determination result from the determination unit 73 of the substrate passage sensor 7, and controls the drive motor 66 of the transport unit 6 based on the determination result. Note that the transport control unit 8 may have a function of controlling the light projecting unit 71, for example, a function of adjusting the brightness of the detection light DL. The transport control unit 8 can obtain the transport distance of the substrate K based on the operation history of the drive motor 66 . Further, the transport control unit 8 recognizes the arrival of the substrate K at the stop position PS based on the determination result of the determination unit 73 and the transport distance obtained from the operation history of the drive motor 66 . Various known methods can be applied as a control method for the drive motor 66, for example, a smooth deceleration control method for preventing the substrate K from suddenly stopping at the stop position PS.

The transport control unit 8 has four control function units configured using software, that is, a setting unit 81, a monitoring unit 82, a resetting unit 83, and an abnormality determination unit 84. The four control function units operate in parallel with the transport operation of the transport unit 6 .

When the transport unit 6 transports the substrate K, the setting unit 81 changes the determination result of the determination unit 73 of the substrate passage sensor 7 from "no substrate" to "no substrate" via "substrate present". A future transport distance D1 for transporting the substrate K to the stop position PS is set. The fact that the determination result has changed from “no substrate” to “with substrate” means that the front end of the substrate K has reached the carry-in end 22 . Further, the time when the determination result changes from "substrate present" to "substrate absent" after that corresponds to the time when the rear end of the normal substrate K passes the carry-in end 22. FIG. Here, the ordinary substrate K means a general rectangular substrate K having no voids. Therefore, the transport distance D1 represents the distance to be transported after the moment when the trailing edge of the substrate K passes the loading end 22 (see FIGS. 6 and 7).

The monitoring unit 82 operates immediately after the setting unit 81 sets the conveying distance D1 at the latest. The monitoring unit 82 monitors whether or not the determination result of the determination unit 73 changes again to "substrate present" until the substrate K reaches the stop position PS. The monitoring unit 82 stores that the determination result has changed again to "substrate present" by the reset flag setting operation. The change of the judgment result of the judging unit 73 to "substrate present" cannot occur with a normal substrate K, but with a cracked substrate KB (see FIG. 8), which will be described later. In the first embodiment, the monitoring unit 82 operates without being constrained by the setting unit 81 and continuously monitors changes in the determination result of the determination unit 73 .

The resetting unit 83 operates when the monitoring unit 82 finds that the determination result of the determination unit 73 has changed to "substrate present" again. In other words, the resetting unit 83 operates with the resetting flag set when the broken substrate KB is transported. The resetting unit 83 resets the set transport distance when the determination result of the determining unit 73 changes again to "substrate present" and then to "substrate absent". Further, the resetting unit 83 resets the future transport distance D1. "Reset" means that the initially set transport distance D1 is gradually corrected to be smaller as the transport of the substrate K progresses after the setting operation of the setting unit 81, but the reduced transport distance is reset. This means that the same conveying distance D1 as at the beginning is set again at this time.

The abnormality determination unit 84 determines whether or not there is an abnormality related to the transport of the board K. The abnormality determination unit 84 obtains the estimated length of the substrate K in the transport direction based on the operation history of the drive motor 66 of the transport unit 6 and the determination result of the determination unit 73 of the substrate passage sensor 7 . More specifically, the abnormality determining unit 84 determines the first time when the determination result of the determining unit 73 changes from "no board" to "with board" and the moment when "with board" changes to "no board". Find the second time. In other words, the abnormality determination unit 84 obtains the first time when the front end of the substrate K passes the loading end 22 and the second time when the rear end of the substrate K passes the loading end 22 .

Furthermore, the abnormality determination unit 84 obtains the transport distance that the drive motor 66 transported the board K from the first time to the second time, and uses it as the estimated length of the board K. The abnormality determination unit 84 compares this estimated length with a previously stored known length LK of the substrate K in the transport direction, and determines that there is an abnormality when the length error exceeds a predetermined allowable value. According to this, an abnormality in which two substrates K are transported while being in contact with each other in the transportation direction, and an abnormality in which a component protruding backward from the substrate K is erroneously detected as the rear end of the substrate K is detected.

The functions and operations of the setting unit 81, the monitoring unit 82, and the resetting unit 83 will be additionally described later in the description of the operation of the substrate transport device 2. On the other hand, the abnormality determination unit 84 is not an essential component and may be omitted. The abnormality determination unit 84 can determine whether or not there is an abnormality when the substrate passage sensor 7 detects the rear end of the substrate K during the operation of the substrate transfer device 2 .

4. Conveyance distance D1 (D2, D3)
Next, the conveying distance D1 described above will be described with reference to FIGS. 2 and 7. FIG. As described above, the stop position PS indicated by the dashed line is set at the center of the guide rail 21 (conveyance path) in the X-axis direction. A distance between the stop position PS and the carry-in end 22 (prescribed position) is D0. On the other hand, the length of the substrate K in the transport direction is LK. Further, an intermediate position PK in the transport direction of the substrate K is indicated by a dashed line. The separation distance D0 and the length LK of the substrate K are known, and the transport distance D1 is obtained in advance before starting the transport operation.

In the first embodiment, the substrate K is controlled to stop so that its intermediate position PK overlaps the stop position PS (see FIG. 7). In this case, the conveying distance D1 is obtained by the following equation (1).
Conveyance distance D1=D0-(LK/2) (1)
That is, the transport distance D1 is a distance obtained by subtracting half the length LK of the substrate K in the transport direction from the separation distance D0 between the stop position PS and the specified position (carry-in end 22).

In addition, when stop control is performed so that the rear end of the substrate K overlaps the stop position PS, the conveying distance D2 is obtained by the following equation (2).
Conveyance distance D2=D0 (2)
That is, the conveying distance D2 matches the separation distance D0 between the stop position PS and the specified position (carrying-in end 22).

Further, when stop control is performed so that the front end of the substrate K overlaps the stop position PS, the conveying distance D3 is obtained by the following equation (3).
Conveyance distance D3=D0-LK (3)
That is, the conveying distance D3 is a distance obtained by subtracting the length LK of the substrate K in the conveying direction from the separation distance D0 between the stop position PS and the specified position (carrying-in end 22).

5. Cracked substrate KB
Next, a configuration example of the cracked substrate KB will be described with reference to FIG. The cracked substrate KB consists of a picture-frame-shaped frame portion KF and two small piece substrates (K1, K2). Each of the small substrates (K1, K2) is coupled to the inside of the frame KF at three points. After the production of the broken substrate KB is completed, each of the small substrates (K1, K2) is separated from the frame KF and used separately.

The length of the broken substrate KB in the transport direction is LB. For the cracked substrate KB as well, the future transport distances (D1, D2, D3) can be obtained by applying the length LB to the equations (1), (2), and (3). A gap portion KG is formed between the small piece substrate K1 on the front side in the transport direction of the broken substrate KB and the small piece substrate K2 on the rear side. Note that the cracked substrate KB may have three or more small piece substrates and a plurality of gaps KG. In the prior art, there is a possibility that the trailing edge of the front small board K1 may be erroneously detected as the trailing edge of the cracked board KB. The first embodiment eliminates the possibility of this false detection.

6. Operation of Substrate Transfer Apparatus 2 Next, the operation of the substrate transfer apparatus 2 will be described with reference to FIGS. 5 to 12. FIG. 5 shows an operation flow of the substrate transfer apparatus 2, FIGS. 6 and 7 show an operation example of transferring a normal substrate K, and FIGS. 8 to 12 show an operation example of transferring a cracked substrate KB. . In the initial state before the transport operation is started, the reset flag used by the monitoring unit 82 is in the reset state.

First, the operation for transporting a normal substrate K will be described. At step S1 in FIG. 5, the transport control unit 8 causes the transport unit 6 to start the transport operation. After that, the transport unit 6 automatically continues the transport operation of the substrate K. FIG. On the other hand, the transport control unit 8 repeats a series of operations after step S2 for each control cycle. In step S<b>2 , the transport control unit 8 acquires the determination result of the determination unit 73 (hereinafter simply referred to as “determination result”), in other words, the detection result of the substrate passing sensor 7 .

In the next step S3, the monitoring unit 82 checks whether or not the previous determination result was "no substrate" and the current determination result changed to "with substrate". The monitoring unit 82 advances the execution of the operation flow to step S4 when the change is made as described above, and otherwise advances the execution of the operation flow to step S11. In step S11, the monitoring unit 82 checks whether or not the previous determination result was "substrate present" and the current determination result changed to "substrate absent". The monitoring unit 82 advances the execution of the operation flow to step S12 when the change is made as described above, and otherwise advances the execution of the operation flow to step S15.

At step S15, the monitoring unit 82 checks whether the substrate K has reached the stop position PS. If not, the monitoring unit 82 returns execution of the operation flow to step S2. The front end of the substrate K has not reached the carry-in end 22 at the initial stage when the transportation of the substrate K is started. Therefore, the transport control unit 8 acquires the determination result of "no substrate" each time step S2 is executed. As a result, an operation loop composed of steps S2, S3, S11, and S15 is repeatedly executed.

When the front end of the substrate K reaches the carry-in end 22, in step S2, the transport control unit 8 acquires the determination result of "substrate present". As a result, execution of the operation flow exits the operation loop from step S3 and proceeds to step S4. In step S4, the monitoring unit 82 determines whether or not it is the first operation (whether or not step S4 has been performed for the first time). If it is the first operation, the monitoring unit 82 returns execution of the operation flow to step S2. When the front end of the substrate K reaches the carry-in end 22, the operation is performed for the first time, so execution of the operation flow is returned to step S2.

After that, while the substrate K is passing through the carry-in end 22, the transport control unit 8 acquires the determination result of "substrate present" each time step S2 is executed. As a result, the operation loop described above is repeatedly executed. As shown in FIG. 6, when the rear end of the substrate K reaches the carry-in end 22, in step S2, the transport control unit 8 acquires the determination result of "no substrate". As a result, execution of the operation flow exits the operation loop from step S11 and proceeds to step S12.

In step S12, the monitoring unit 82 determines the branch destination of the operation flow depending on whether the reset flag is set. When the rear end of the substrate K reaches the carry-in end 22, the reset flag is in the initial reset state, so execution of the operation flow proceeds to step S13. In step S13, the setting unit 81 determines the trailing edge of the substrate K, and performs the operation of setting the transport distance D1 from now on. Thereafter, execution of the operation flow returns to step S2 via step S15.

After the trailing edge of the substrate K has passed the carry-in edge 22, the transport control unit 8 acquires the determination result of "no substrate" each time step S2 is executed. As a result, the operation loop described above is repeatedly executed. During the repetition, the transport control unit 8 gradually corrects the future transport distance D1 to be smaller as the transport of the substrate K progresses. Then, when the substrate K approaches the stop position PS, the transport control unit 8 appropriately decelerates the transport unit 6 .

When the substrate K reaches and stops at the stop position PS as shown in FIG. 7, execution of the operation flow exits the operation loop from step S15 and ends. When transporting a normal substrate K, steps S5 and S14 of the operation flow are not executed, and the reset flag is not used. In addition, resetting unit 83 does not operate.

Second, the operation for transporting the cracked substrate KB will be described. At step S1 in FIG. 5, the transport control unit 8 causes the transport unit 6 to start the transport operation. In the next step S<b>2 , the transport control section 8 acquires the determination result of the determination section 73 . At the initial stage when the transportation of the broken substrate KB is started, the transportation control unit 8 acquires the determination result of “no substrate” each time step S2 is executed. As a result, an operation loop composed of steps S2, S3, S11, and S15 is repeatedly executed.

When the front end of the cracked substrate KB reaches the carry-in end 22, in step S2, the transport control unit 8 acquires the determination result of "substrate present". As a result, execution of the operation flow exits the operation loop from step S3 and proceeds to step S4. In step S4, the monitoring unit 82 returns the execution of the operation flow to step S2 because it is the first operation. Thereafter, while the front portion of the frame KF and the front small-piece substrate K1 are passing through the carry-in end 22, the transport control unit 8 acquires the determination result of "substrate present" each time step S2 is executed. As a result, the operation loop described above is repeatedly executed.

As shown in FIG. 9, when the trailing edge of the small board K1 reaches the carry-in end 22, in step S2, the transport control unit 8 acquires the determination result of "no board". As a result, execution of the operation flow exits the operation loop from step S11 and proceeds to step S12. In step S12, since the reset flag is set in the monitoring unit 82, the execution of the operation flow proceeds to step S13. In step S13, the setting unit 81 determines the trailing edge of the cracked substrate KB, and performs the operation of setting the transport distance D1 from now on. However, this determination and setting operation is not for the trailing edge of the cracked substrate KB and is erroneous. Thereafter, execution of the operation flow returns to step S2 via step S15.

While the gap KG of the cracked substrate KB is passing through the carry-in end 22, the transport control unit 8 acquires the determination result of "no substrate" each time step S2 is executed. As a result, the operation loop described above is repeatedly executed. During the repetition, the transport control unit 8 gradually corrects the future transport distance D1 to be smaller as the transport of the substrate K progresses.

As shown in FIG. 10, when the front edge of the rear small piece substrate K2 reaches the carry-in end 22, in step S2, the transport control unit 8 acquires the determination result of "substrate present". Therefore, the monitoring unit 82 recognizes that the determination result has changed to "substrate present" again. As a result, execution of the operation flow exits the operation loop from step S3 and proceeds to step S4. In step S4, the monitoring unit 82 advances the execution of the operation flow to step S5 because it is the second operation.

After setting the reset flag in step S5, the monitoring unit 82 returns the operation flow to step S2. After that, while the small substrate K2 and the rear portion of the frame KF are passing through the carry-in end 22, the transport control unit 8 acquires the determination result of "substrate present" each time step S2 is executed. As a result, the operation loop described above is repeatedly executed. During the repetition, the transport control unit 8 gradually corrects the future transport distance to be smaller.

As shown in FIG. 11, when the rear end of the broken substrate KB reaches the carry-in end 22, in step S2, the transport control unit 8 acquires the determination result of "no substrate". As a result, execution of the operation flow exits the operation loop from step S11 and proceeds to step S12. In step S12, since the reset flag is set (already set in step S5), the monitoring unit 82 advances the operation flow to step S14.

In step S14, the resetting unit 83 determines the correction of the rear end of the cracked substrate KB, and resets the transport distance D1 from now on. As a result, the conveying distance set in step S13 and gradually corrected to be smaller is reset, and the same conveying distance D1 as the initial one is set again at this time. In other words, the erroneous setting in step S13 is reset and the correct setting is made in step S14. The resetting unit 83 resets the resetting flag after normally completing the resetting operation. Thereafter, execution of the operation flow returns to step S2 via step S15.

After the rear end of the cracked substrate KB has passed the carry-in end 22, the transport control unit 8 acquires the determination result of "no substrate" each time step S2 is executed. As a result, the operation loop described above is repeatedly executed. During the repetition, the transport control unit 8 appropriately controls the transport unit 6 based on the transport distance D1 reset in step S14.

Finally, the cracked substrate KB reaches the stop position PS and stops, as shown in FIG. Then, execution of the operation flow exits the operation loop from step S15 and ends. When transporting a cracked substrate KB in which a plurality of gaps KG are spaced apart in the transport direction, steps S5 and S14 are executed the number of times corresponding to the number of gaps KG. Therefore, the resetting unit 83 operates the number of times corresponding to the number of the gaps KG. On the other hand, step S13 is executed only once regardless of the presence or absence of the gaps KG and the number thereof. Therefore, the setting unit 81 operates only once regardless of the type of substrate (K, KB).

In the substrate conveying apparatus 2 of the first embodiment, when the detection result of the substrate passage sensor 7 changes from "no substrate" to "no substrate" via "substrate present", the trailing edge of the substrate (K, KB) is detected. Then, the transport distance D1 from now on is set. Then, when the detection result changes to "substrate present" again, when the detection result subsequently changes to "substrate absent", it is determined to be the rear end of the cracked substrate KB, and the set transport distance is reset. The future transport distance D1 is set again. According to this, even if the trailing edge is erroneously determined due to the presence of the gap KG of the cracked substrate KB, the transport distance D1 from now on is restarted when the true trailing edge of the cracked substrate KB is determined to be corrected. set. Therefore, the detection accuracy of the rear end of the board (K, KB) can be improved more than before, and as a result, the board-to-board work machine (component mounting machine 1) can be stopped due to an error in transportation, or the board (K, KB) can be detected. ) of the stop position can be reduced more than before.

In addition, the control method of the transport control unit 8 based on the detection result of the substrate passing sensor 7 is common to all types of substrates (K, KB). Therefore, in the first embodiment, the operator's labor is greatly reduced compared to the conventional technique in which the timer is set and the transport distance is adjusted for each of a plurality of board-to-board work machines for each type of board.

7. 2A of board|substrate conveying apparatuses of 2nd Embodiment
Next, with reference to FIGS. 13 and 14, the substrate transfer apparatus 2A of the second embodiment will be described mainly with respect to the differences from the first embodiment. In the second embodiment, the configurations of the transport section 6 and the transport control section 8 are the same as in the first embodiment. On the other hand, the substrate passage sensor 7A of the second embodiment employs a horizontal passage type that projects the detection light DL in the horizontal direction and detects the presence or absence of the substrate K based on the amount of passage of the detection light DL. The board passage sensor 7A is composed of a light projecting section 74, a light receiving section 75, and a determining section 73 which is the same as in the first embodiment.

As shown in FIG. 13, the light projecting part 74 is arranged outside the carry-in end 22 (prescribed position) of one of the guide rails 21 in the Y-axis direction. The light projecting part 74 projects the detection light DL in the horizontal direction orthogonal to the transport direction toward the substrate K in the horizontal posture passing through the carry-in end 22 . The light receiving portion 75 is arranged at a position on the opposite side of the light projecting portion 74 with the substrate K therebetween, in other words, outside the carry-in end 22 (prescribed position) of the other guide rail 21 in the Y-axis direction. The light receiving section 75 detects the passing amount of the detection light DL.

In the substrate transfer apparatus 2A of the second embodiment, when transferring the warped substrate KS, the detection accuracy of the trailing edge can be improved more than in the past. More specifically, in FIG. 14, the warped substrate KS is warped such that the intermediate portion in the transport direction protrudes upward, and the degree of warping is exaggerated. In the transport operation of the warped substrate KS, when the front portion and the rear portion of the warped substrate KS pass through the carry-in end 22, the passing amount of the detection light DL decreases. Meanwhile, when the intermediate portion of the warped substrate KS passes through the carry-in end 22, the detection light DL passes under the warp as shown in the drawing, and the passing amount increases temporarily.

That is, the warped intermediate portion of the warped substrate KS has the same effect as the gap KG of the cracked substrate KB. As a result, when the warped substrate KS is transported, the determination result of the determination unit 73 of the substrate passage sensor 7A follows the same transition as in the case of transporting the cracked substrate KB in the first embodiment. Therefore, even if the trailing edge is erroneously determined due to the presence of the warped portion of the warped substrate KS, the future transport distance D1 is reset when the true trailing edge of the warped substrate KS is determined to be corrected. According to this, it is possible to improve the detection accuracy of the rear end of the warped board KS as compared with the conventional one. A decrease in positional accuracy can be reduced more than before.

8. Substrate transfer device 2B of the third embodiment
Next, the substrate transfer apparatus 2B of the third embodiment will be described with reference to FIG. 15, mainly on the points different from those of the first and second embodiments. In the third embodiment, the board passing sensor 7B employs a vertical reflection type that projects the detection light DL in the vertical direction and detects the presence or absence of the board K based on the amount of reflection of the detection light DL. The board passage sensor 7B is composed of a light projecting section 76, a light receiving section 77, and a determination section (not shown).

As shown in FIG. 15, the light projecting part 76 is arranged at a position above the carry-in end 22 in a posture slightly inclined from the vertical direction. The light projecting unit 76 projects obliquely downward detection light DL toward the horizontal substrate K passing through the carry-in end 22 . On the other hand, the light-receiving part 77 is arranged in a position aligned with the light-projecting part 76 and corresponding to the path of the detection light DL reflected by the substrate K in a posture slightly inclined from the vertical direction. The light receiving section 77 detects the amount of reflection of the detection light DL.

The determination unit receives information on the amount of reflection of the detection light DL from the light receiving unit 77. The determining unit determines that there is no substrate when the amount of reflection is less than a predetermined threshold, and determines that there is a substrate when the amount of reflection is equal to or greater than the threshold. The board transfer device 2B of the third embodiment differs from the first embodiment in the detection method of the board passing sensor 7B, but its operation, function and effect are substantially the same as those of the first embodiment.

9. Applications and Modifications of the Embodiments The board transfer devices (2, 2A, 2B) can also be applied to work machines other than the component mounting machine 1, such as a solder printing machine and a board inspection machine. Further, the substrate passage sensor may be of a horizontal reflection type that projects detection light in the horizontal direction and detects the presence or absence of the substrate K based on the amount of reflection of the detection light. Furthermore, even if the length LK of the substrate K in the transport direction is unknown, the substrate transport devices (2, 2A, 2B) use the estimated length obtained by the abnormality determination unit 84 to calculate the future transport distance D1. and the substrate K can be stopped at a predetermined stop position PS. However, the abnormality determination by the abnormality determination unit 84 cannot be performed. Various other applications and modifications are possible for the first to third embodiments.

1:

Component mounting machine

2, 2A, 2B: Substrate transfer device 21: Guide rail 22: Carry-in end 3: Component supply device 4: Component transfer device 6: Transfer section 61: Conveyor belt 65: Drive pulley 66: Drive

motor

7 , 7A, 7B: Substrate passing sensor 71: Light emitting part 72: Light receiving part 73: Judging part 74: Light emitting part 75: Light receiving part 76: Light emitting part 77: Light receiving part 8: Conveyance control part 81: Setting part 82: Monitoring unit 83: Reset unit 84: Abnormal judgment unit DL: Detection light PS: Stop position D0: Spacing distance D1: Transfer distance K: Substrate PK: Intermediate position LK: Length KB: Cracked substrate KF: Frame K1, K2 : Small board KG: Gap part LB: Length KS: Warped board

Claims

a transport unit that transports the substrate from the carry-in end of the transport path to a predetermined stop position;
A detection light is projected toward the substrate passing through a specified position on the carry-in end side of the transport path relative to the stop position, and the substrate at the specified position is detected based on the amount of passage or reflection of the detection light. a substrate passage sensor that detects the presence or absence of
When the transport unit transports the substrate, the substrate is transported to the stop position when the detection result of the substrate passage sensor changes from "substrate present" to "substrate absent". a setting unit for setting a future conveying distance;
a monitoring unit for monitoring whether or not the detection result changes to "substrate present" again until the substrate reaches the stop position;
When the detection result changes to "substrate present" again, when the detection result subsequently changes to "substrate absent", the already set transport distance is reset and the future transport distance is set again. a setting unit;
A substrate transport device comprising:
2. The substrate transport apparatus according to claim 1, wherein said substrate passage sensor projects said detection light in a vertical direction toward said substrate transported in a horizontal posture.
2. The substrate transport apparatus according to claim 1, wherein said substrate passage sensor projects said detection light in a horizontal direction intersecting the transport direction toward said substrate transported in a horizontal posture.
The substrate passing sensor is
a light projecting unit that projects the detection light toward the substrate;
a light-receiving unit disposed on the opposite side of the light-projecting unit with the substrate interposed therebetween, and detecting the amount of the detection light passing through that decreases when the substrate is present compared to when the substrate is not present;
a determination unit that determines that there is no substrate when the passing amount is equal to or greater than a predetermined threshold, and determines that there is a substrate when the passing amount is less than the threshold;
A substrate transfer apparatus according to any one of claims 1 to 3.
The substrate passing sensor is
a light projecting unit that projects the detection light toward the substrate;
a light receiving unit arranged side by side with the light projecting unit for detecting the amount of reflection of the detection light that increases when the substrate is present compared to when the substrate is not present;
a determination unit that determines that there is no substrate when the amount of reflection is less than a predetermined threshold, and determines that there is a substrate when the amount of reflection is equal to or greater than the threshold;
A substrate transfer apparatus according to any one of claims 1 to 3.
The transport distance is the separation distance between the stop position and the specified position, the distance obtained by subtracting half the length of the substrate in the transport direction from the separation distance, and the length of the substrate in the transport direction from the separation distance. 6. The substrate transfer apparatus according to any one of claims 1 to 5, wherein the distance is any one of the distances obtained by subtracting .
An estimated length of the substrate in the transport direction is obtained based on the operation history of the transport unit and the detection result of the substrate passage sensor, and the estimated length and the known length of the substrate in the transport direction are compared to detect an abnormality. The substrate transfer apparatus according to any one of claims 1 to 6, comprising an abnormality determination unit that determines the presence or absence of a
a transport unit that transports the substrate from the carry-in end of the transport path to a predetermined stop position;
A detection light is projected toward the substrate passing through a specified position on the carry-in end side of the transport path relative to the stop position, and the substrate at the specified position is detected based on the amount of passage or reflection of the detection light. a substrate passage sensor that detects the presence or absence of
A substrate transport apparatus comprising a control unit that controls the transport unit based on a detection result of the substrate passage sensor,
The control unit
When the transport unit transports the substrate, when the detection result changes from "no substrate" to "no substrate" via "substrate present", a future transport distance for transporting the substrate to the stop position and set
until the substrate reaches the stop position, monitoring whether the detection result changes again to "substrate present";
When the detection result changes again to "substrate present", when the detection result subsequently changes to "substrate absent", resetting the set transport distance and resetting the future transport distance;
Substrate transfer method.