JP5203079B2 - Substrate fixing device - Google Patents

Description

  The present invention relates to a substrate fixing mechanism for fixing a substrate in a substrate inspection apparatus and a substrate moving apparatus, and a substrate fixing apparatus including the mechanism.

  In a board inspection apparatus for inspecting a printed wiring board or a board mounted with components, it is necessary to fix the position of the board in advance. A substrate fixing mechanism for fixing the position of such a substrate is described in Patent Document 1, for example. In the position fixing mechanism of the substrate to be inspected described in Patent Document 1, the one side chuck part and the other side chuck part are arranged on the base so as to be biased toward each other. This is fixed by sandwiching the board to be inspected at the part.

  In an inspection apparatus that automatically inspects a large number of substrates, a substrate placement device places a substrate on a substrate fixation mechanism (substrate fixation device) as described in Patent Document 1 on a substrate set stage. When the substrate is placed, the substrate is fixed and the base moves to the substrate inspection stage. When the substrate inspection is completed, the base moves to the substrate take-out stage, and the substrate is taken out.

  In such an inspection apparatus, the substrate may not be placed or the substrate may be dropped due to, for example, malfunction of the substrate placing apparatus. In addition, the substrate may fall while the substrate fixing mechanism is moving. Therefore, it is necessary to detect whether or not the substrate is fixed to the substrate fixing device.

  Patent Document 2 describes a substrate carry-out device that includes an optical sensor and detects a positional shift of a substrate holder.

  For example, by disposing an optical sensor as described in Patent Document 2 at a position below the base of the substrate set stage, it detects the displacement of the chuck portion of the position fixing mechanism and detects whether the substrate is fixed. can do.

JP 2006-30049 A JP 2004-241484 A

  However, even if an optical sensor as described in Patent Document 2 is installed, the presence or absence of the substrate can be detected only at the place where the optical sensor is installed. For this reason, in the apparatus in which the substrate fixing mechanism moves sequentially, there is a problem that when the substrate falls after the place where the optical sensor is installed, the fall cannot be detected. Moreover, there is a problem that the structure becomes complicated by providing the optical sensor.

  The present invention has been made to solve these problems, and an object of the present invention is to provide a substrate fixing mechanism and a substrate fixing device that can always detect whether or not the substrate is fixed while having a simple structure. .

The substrate fixing device according to claim 1, which has been made to achieve the above object, is provided in an inner space of a pneumatic cylinder in which a piston with a piston ring is fitted in the cylinder portion. Provided with a moving chuck that is driven by the piston and that presses and fixes the substrate when supplied with compressed air, an air hole that communicates the inside and outside of the cylinder portion is formed, and the air hole includes the moving chuck. When the inner ring is kept confidential by the piston ring when the substrate is fixed, and the movable chuck is moved further than the position where the substrate is fixed. a board securing mechanism internal empty confidentiality is formed at a position that is released the piston rings past at least a portion of the air pores, the leakage of the compressed air from the air hole A sensor for detecting a feature in that it comprises a substrate detection unit the substrate is determined to not fixed upon detecting the leakage of compressed air from the air pores based on the detected value of the sensor To do.

A substrate fixing device according to a second aspect is the substrate fixing device according to the first aspect , wherein the sensor detects a pressure of the compressed air supplied to the pneumatic cylinder, or of the compressed air. It is a flow rate sensor that detects a flow rate.

  In the substrate fixing mechanism according to the present invention, from the position where the confidentiality of the inner space of the cylinder portion is maintained by the piston ring when the moving chuck fixes the substrate, and the position where the moving chuck fixes the substrate. When the piston ring is further driven and moved, the air hole is formed at a position where the confidentiality of the inner space is released through the air hole. Thereby, when the substrate is fixed, the compressed air does not leak, and when the substrate is not fixed, the compressed air leaks and flows out from the air hole. Therefore, the substrate fixing mechanism can always detect whether or not the substrate is fixed by detecting whether or not the compressed air leaks. This mechanism is a simple structure in which air holes are simply formed.

  A substrate fixing device according to the present invention includes a substrate fixing mechanism, a sensor for detecting leakage of compressed air from an air hole, and a substrate detection unit. The substrate detection unit is configured to perform air detection based on a detection value of the sensor. When a leak of compressed air from the hole is detected, it is determined that the substrate is not fixed. Thereby, it can be reliably detected that the substrate is not fixed.

  In the substrate fixing device according to the present invention, the sensor is a pressure sensor that detects the pressure of the compressed air supplied to the pneumatic cylinder, or a flow rate sensor that detects the flow rate of the compressed air. Since it is only necessary to arrange the sensor, it is not necessary to arrange the sensor on the substrate fixing mechanism itself, and the degree of freedom in arranging the sensor increases. In addition, the substrate fixing device may require a pressure sensor or a flow rate sensor for other functions. In this case, the sensor can be shared, so that the device cost does not increase.

Preferred form for carrying out the invention

  Examples of the present invention will be described in detail below, but the scope of the present invention is not limited to these examples.

  FIG. 1 shows a schematic view observed from the upper surface of the substrate fixing mechanism of the present invention. FIG. 1 shows the state of operation of the substrate fixing mechanism in use in FIGS. 1 (a) to 1 (c). In the figure, the pneumatic cylinder 4 is shown in cross section, and the dimensions of each part of the pneumatic cylinder 4 are shown exaggerated from the actual ones for easy understanding of the present invention.

  As shown in FIG. 1A, a fixed chuck 2, a moving chuck 3, and a pneumatic cylinder 4 are arranged on a base 5 in the substrate fixing mechanism 1. The position of the fixed chuck 2 is fixed on the base 5 and is formed in a shape that comes into contact with two adjacent sides of the substrate 50 to be fixed as shown in FIG. Further, the fixed chuck 2 has an L-shaped support claw for supporting the substrate 50 from the lower side along the two adjacent sides in contact with the fixed chuck 2. A hole 19 is formed in the base 5 below the position where the substrate 50 is fixed. The hole 19 is for raising the placement auxiliary base from below when placing the substrate 50.

  The moving chuck 3 is formed in a shape that contacts the remaining two adjacent sides of the substrate 50. The movable chuck 3 has an L-shaped support claw that supports the substrate 50 from below along the two adjacent sides. The moving chuck 3 is mounted on a rail (not shown) on the base 5 in a direction facing the fixed chuck 2 so as to be movable forward and backward in the direction of the fixed chuck 2. In addition, a tension spring 18 is spanned between the movable chuck 3 and the base 5.

  The pneumatic cylinder 4 is configured such that a piston 12 with a piston ring 13 is fitted into a cylinder portion 11, and the piston 12 can be operated by supplying compressed air to an air chamber 14 inside the cylinder portion 11. It is configured. The position of the pneumatic cylinder 4 is fixed on the base 5.

  As an example, the piston 12 is formed in a stepped columnar shape having a large-diameter body portion and a small-diameter rod portion. An annular groove is formed on the side surface of the body portion, and an annular piston ring 13 made of rubber is fitted into the groove.

  The cylinder part 11 forms the outer wall of the pneumatic cylinder 4, and the inner space is formed in a cylindrical shape with a substantially larger diameter than the body part of the piston 12. Further, a compressed air inlet having a smaller diameter than the inner air diameter is formed at the left end (left side in the drawing) of the cylinder portion 11. Further, a hole is formed at a right end (right side in the figure) of the cylinder portion 11 with a diameter substantially larger than that of the rod portion of the piston.

  A piston 12 is inserted into the cylinder portion 11, and a rod portion of the piston 12 protrudes from a hole at the right end of the cylinder portion 11 and is fixed to the moving chuck 3. The piston ring 13 closes a gap between the body portion of the piston 12 and the inner wall of the cylinder portion 11. The space inside the cylinder portion 11 from the compressed air inlet to the piston ring 13 becomes an air chamber 14.

  Furthermore, the cylinder part 11 is formed with an air hole 15 that communicates the inner space with the outside. The air holes 15 are in a state before the substrate 50 is fixed as shown in FIG. 1A or when the movable chuck 3 places the substrate 50 in a fixed state as shown in FIG. The piston ring 13 is formed at a position where the confidentiality of the air chamber 14 is maintained. In addition, as shown in FIG. 1C, the air hole 15 has at least one of the piston hole 13 and the air hole 15 when the moving chuck 3 is moved further than the position where the substrate 50 is fixed. The air chamber 14 is formed at a position where the confidentiality of the air chamber 14 is released.

  FIG. 2A shows a control system block diagram of the substrate fixing apparatus of the present invention.

  The substrate fixing device includes the substrate fixing mechanism 1 described above, a pressure sensor 20 which is an example of a sensor for detecting leakage of compressed air from the air holes 15, and a substrate detection unit 21. The substrate detection unit 21 determines that the substrate 50 is not fixed when leakage of compressed air from the air hole 15 is detected based on the detection value of the pressure sensor 20. Details will be described below.

  As shown in the figure, a pressure sensor 20 that detects the pressure of compressed air is disposed in the compressed air flow path to the pneumatic cylinder 4 of the substrate fixing mechanism 1. Since this position should just be on a compressed air flow path, the freedom degree of arrangement | positioning is large. The pressure sensor 20 is connected to the substrate detection unit 21 and outputs a detected pressure value (detected value).

  The substrate detection unit 21 includes a central processing unit and a memory, and is also used as a control unit that controls the operation of the entire substrate fixing device. The substrate detection unit 21 detects the presence or absence of the substrate 50 based on the detected pressure value detected by the pressure sensor 20.

  Specifically, the substrate detection unit 21 includes a minimum pressure (hereinafter referred to as a pressure value) that can be detected by the pressure sensor 20 in a state where the movable chuck 3 fixes the substrate 50 as shown in FIG. , Referred to as “pressure threshold”). When the compressed air is supplied to the pneumatic cylinder 4, the substrate detection unit 21 performs the substrate detection process A according to the flowchart shown in FIG. In this substrate detection processing A, the substrate detection unit 21 compares the detected pressure value detected by the pressure sensor 20 with the pressure threshold value (step 40). It is determined that it is present, that is, normally fixed (step 41). In step 40, if the detected pressure value is smaller than the pressure threshold value, the substrate detection unit 21 determines that the substrate 50 is not present, that is, is not fixed (step 42). The process (step 43) is executed. The substrate detection unit 21 repeats the processing of steps 40 and 41 to perform loop processing.

  First, the operation of the substrate fixing device when the substrate 50 is normally fixed to the substrate fixing mechanism 1 will be described.

  First, the substrate fixing mechanism 1 is moved to the substrate set stage. At this time, compressed air is not supplied to the pneumatic cylinder 4, and the moving chuck 3 and the piston 12 move away from the fixed chuck 2 by the urging force of the tension spring 18, as shown in FIG. doing. Thereby, a large opening is formed between the fixed chuck 2 and the movable chuck 3.

  In this state, the substrate 50 is automatically placed between the fixed chuck 2 and the movable chuck 3. At this time, a mounting auxiliary table (not shown) that supports the substrate 50 from below is raised.

  When the substrate 50 is placed, compressed air is supplied to the pneumatic cylinder 4. As a result, as indicated by a two-dot chain line Air in FIG. 1B, the compressed air is supplied to the air chamber 14 so that the piston 12 can resist the urging of the tension spring 18 by the pressure of the compressed air. Operates and moves to the right in the figure. Accordingly, the movable chuck 3 is driven in the direction of the fixed chuck 2 and comes into contact with the substrate 50 to press and fix the substrate 50. At a predetermined timing after the compressed air is supplied, the placement auxiliary table is lowered.

  The board detection unit 21 starts the board detection process A described above when compressed air is supplied to the pneumatic cylinder 4. The board | substrate detection part 21 compares the detected pressure value from the pressure sensor 20, and the pressure threshold value recorded beforehand by step 40 shown by Fig.3 (a).

  In the case shown in FIG. 1 (b), even if the piston 12 is actuated, the moving chuck 3 comes into contact with the substrate 50 and stops, so that the piston ring 13 is positioned on the inlet side of the air hole 15. Stop at. For this reason, the confidentiality of the air chamber 14 is maintained. Therefore, the compressed air supplied to the pneumatic cylinder 4 does not leak and maintains its pressure. Thereby, since the detected pressure value is equal to or higher than the pressure threshold value, the substrate detection unit 21 determines that the substrate 50 is present (step 41).

  The substrate fixing mechanism 1 sequentially moves from the substrate set stage to the inspection stage and the substrate take-out stage. During this time, the substrate detection unit 21 continues the substrate detection process A. When the supply of compressed air is stopped at the substrate take-out stage, the substrate detection unit 21 ends the process.

  Next, the operation of the substrate fixing device when the substrate 50 is not fixed to the substrate fixing mechanism 1 will be described.

  In this case, the substrate 50 is not fixed because the substrate 50 falls or moves upward from the fixed chuck 2 and the moving chuck 3. Moreover, even if the board | substrate 50 is once fixed, the case where it falls from the board | substrate fixing mechanism 1 during the movement of the board | substrate fixing mechanism 1 is also assumed.

  In this case, unlike the above, the moving chuck 3 does not come into contact with the substrate 50 and does not stop as shown in FIG. 1B, so that the piston 12 further moves to the right in the drawing. Thereby, as shown in FIG. 1C, the piston ring 13 passes through the air hole 15.

  Thereby, the confidentiality of the air chamber 14 is released, and the supplied compressed air flows out through the air holes 15 as indicated by a two-dot chain line Air in FIG. For this reason, the pressure in the compressed air flow path decreases, and the detected pressure value becomes smaller than the minimum pressure value. Therefore, the substrate detection unit 21 determines that there is no substrate in the substrate detection processing A (steps 40 and 42). Note that the piston 12 stops when its body part hits the right end of the cylinder part 11.

  When the substrate detection unit 21 determines that there is no substrate in step 42, for example, the substrate detection unit 21 is allowed to pass through the substrate fixing device without performing inspection on the substrate inspection stage, or the entire inspection device including the substrate fixing device. The processing when the substrate is dropped or the substrate is dropped (step 43) is performed.

  Since the substrate detection unit 21 always performs the substrate detection process A while the compressed air is supplied, even if the substrate 50 is dropped after being fixed to the substrate fixing mechanism 1, it can be detected.

  As described above, according to the substrate fixing mechanism 1 and the substrate fixing device of the present invention, unlike the conventional device in which the optical sensor is arranged at a specific location, the presence or absence of the substrate 50 can always be detected. The mechanism is a simple structure that simply forms the air hole 15 in the cylinder portion 11 of the pneumatic cylinder 4.

  In the above description, the example in which the pressure sensor 20 is arranged in the compressed air supply path to the pneumatic cylinder 4 has been described. However, as shown in FIG. 2B, this is an example of the sensor of the present invention. A flow rate sensor 20a that detects the flow rate of the compressed air can also be arranged. The flow rate sensor 20a is connected to the substrate detection unit 21a and outputs a detected flow rate value (detection value). This board | substrate detection part 21a implements the board | substrate detection process B which detects the presence or absence of the board | substrate 50 based on the detected flow volume value detected by the flow sensor 20a.

  As shown in FIG. 1B, when the moving chuck 3 is fixing the substrate 50, the compressed air hardly flows because it does not leak from the air holes 15. On the other hand, as shown in FIG. 1C, when the substrate 50 is not fixed, the compressed air leaks from the air holes 15 and flows. In order to detect this flow rate difference, the maximum detected flow rate value (hereinafter referred to as “flow rate threshold value”) that can be measured in the state of FIG.

  The substrate detection unit 21a performs the substrate detection process B shown in the flowchart of FIG. In addition, the same code | symbol is attached | subjected to the process similar to the above-mentioned board | substrate detection process A. FIG. When the compressed air is being supplied to the pneumatic cylinder 4, the substrate detection unit 21a compares the detected flow rate value detected by the flow rate sensor 20a with a flow rate threshold value (step 40a). If the detected flow rate value is less than or equal to the flow rate threshold value, it is determined that the substrate 50 is present (step 41). Moreover, the board | substrate detection part 21a discriminate | determines that there is no board | substrate 50, when a detected flow volume value is larger than a flow volume threshold value (step 42), and performs the process at the time of board | substrate absence and a board | substrate fall (step 43). The substrate detection unit 21a loops the steps 40a and 41.

  The flow rate threshold value and the pressure threshold value can be appropriately changed and used as long as they can detect that compressed air flows out of the air hole 15.

  In the above description, an example in which the fixed chuck 2 does not move but only the movable chuck 3 moves has been described. However, a movable chuck is disposed on both sides of the substrate 50, and the pair of movable chucks are linked by a link mechanism or the like. Then, the substrate 50 may be fixed by movably connecting the pair of moving chucks with one pneumatic cylinder 4. Even in this case, whether or not the substrate is fixed can be detected by detecting leakage from the air hole 15 of the pneumatic cylinder 4.

  A plurality of air holes 15 in the pneumatic cylinder 4 may be formed.

It is a schematic diagram of the board | substrate fixing mechanism to which this invention is applied. It is a control system block diagram of the board | substrate fixing apparatus to which this invention is applied. It is a flowchart which shows operation | movement of the board | substrate detection part to which this invention is applied.

Explanation of symbols

  1 is a substrate fixing mechanism, 2 is a fixed chuck, 3 is a moving chuck, 4 is a pneumatic cylinder, 5 is a base, 11 is a cylinder part, 12 is a piston rod, 13 is a piston ring, 14 is an air chamber, and 15 is an air hole , 18 is a tension spring, 19 is a hole, 20 is a pressure sensor, 20a is a flow sensor, 21 and 21a are substrate detectors, 40 to 43 and 40a are steps in the flowchart, 50 is a substrate, A and B are substrate detection processes, Air is the flow direction of compressed air.

Claims (2)

A movable chuck that is driven by the piston and presses and fixes the substrate by supplying compressed air to the inside of the cylinder portion of a pneumatic cylinder in which a piston with a piston ring is fitted in the cylinder portion;
An air hole is formed to communicate the inner space of the cylinder portion with the outside, and the air hole maintains confidentiality of the inner space by the piston ring when the moving chuck fixes the substrate. And the piston ring passes through at least a part of the air hole when the moving chuck is moved further than the position where the moving chuck is fixed to the substrate. a board fixing mechanism formed at a position that,
A sensor for detecting leakage of the compressed air from the air hole;
A substrate fixing apparatus, comprising: a substrate detection unit that determines that the substrate is not fixed when leakage of compressed air from the air hole is detected based on a detection value of the sensor . Wherein the sensor, the pressure sensor detects the pressure of the compressed air supplied to the pneumatic cylinder, or a substrate fixing device according to claim 1, characterized in that a flow sensor for detecting the flow rate of the compressed air .

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