Drying device

Abstract

To provide a drying device which improves the reliability of the device by stacking and holding carriers on which workpieces are placed without providing a driving source or a sensor in a drying chamber, thereby preventing breakdowns and malfunctions due to heat damage. [Solution] The first lifting mechanism 7a and the second lifting mechanism 7b have first holding claws 9a and second holding claws 9b that hold a predetermined number of carriers K stacked inside the drying chamber 2a by supporting the carrier stack at both side edges, and each holding a predetermined number of carriers K. The first holding claws 9a and second holding claws 9b are suspended and supported around a pivot axis by a claw support member 8 laid vertically inside the drying chamber 2a, and the first holding claws 9a and second holding claws 9b are opened and closed by power transmitted from an air cylinder 10 located outside the drying chamber 2a and thermally insulated from the bottom of the drying chamber 2a.

Description

[Technical Field]

[0001] The present invention relates to a drying device used in a heating and drying process for workpieces such as plate-shaped precision parts, resins covering precision electronic parts such as substrates, and coated protective layers. [Background technology]

[0002] The present applicant has previously proposed a drying apparatus for transporting workpieces in a work drying chamber during the manufacturing process of electronic precision components such as circuit boards, without the need for chains or conveyor belts, which can cause dust generation and thermal degradation. This drying apparatus includes a sealed work drying chamber for transporting and drying workpieces housed in the chamber; a hanging rod inserted into the chamber through a partition plate that closes the work drying chamber and reciprocates along a guide hole formed in the partition plate while supporting the workpiece; a slide plate that overlaps the guide hole and through which the hanging rod passes, sliding together with the hanging rod; and driven plates on both sides of the slide plate that cover the openings of the guide holes that open as the slide plate slides (see Patent Document 1: JP 2009-19820 A). This prevents hot air from escaping through the guide holes in the partition plate of the drying chamber, improving thermal efficiency and preventing thermal damage to the drive mechanism.

[0003] The applicant has also proposed a drying device that includes a first lifting mechanism that stacks the workpieces on a carrier while lifting them from the bottom of the drying chamber toward the top plate, and a second lifting mechanism that sequentially transfers the topmost workpiece from the first lifting mechanism using a work transfer mechanism and lowers it while stacking it. When the lowest carrier in the first lifting mechanism comes into close contact with the carrier located one level above it, the hook-shaped first holding claw hooked onto the bottom of the carrier is rotated in a direction away from the carrier to release support for the carrier stack. When the carrier stack has been raised by the first lifting mechanism by the height of one carrier, the first holding claw is rotated in a direction approaching the lowest carrier, so that the carrier stack stacked above is once again supported.

[0004] The top carrier stacked and supported by the first lifting mechanism is held by the workpiece holding portion of the workpiece transfer mechanism and handed over to second holding claws provided on the adjacent second lifting mechanism. The second holding claws are arranged on both sides of the carrier, supported so as to be movable in the vertical direction, and can be opened and closed at any height (see Patent Document 2: JP 2021-89130 A). This allows the first lifting mechanism to continuously load undried workpieces into the drying chamber, and the second lifting mechanism to continuously remove dried workpieces from the drying chamber, thereby improving the efficiency of the workpiece drying process. The opening and closing operations of the first and second holding claws are performed by a drive source such as an air cylinder provided in the drying chamber. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-19820 [Patent Document 2] Patent Publication No. 2021-89130 Summary of the Invention [Problem to be solved by the invention]

[0006] However, as the size of the workpieces increases, the movement distance of the transfer mechanism increases when the workpieces stored in a drying chamber are circulated and transferred within the drying chamber.In this case, the elongated guide hole through which the hanging rod that connects the transfer mechanism provided outside the drying chamber to the workpiece holder provided inside the drying chamber moves cannot be blocked by the driven plate shown in Patent Document 1 alone.

[0007] In addition, in the drying device of Patent Document 2, a driving source such as an air cylinder that opens and closes the first holding claw and the second holding claw that hold the carrier laminate in the drying chamber is arranged according to the position of the claw. An air tube is connected to the air cylinder, and reed switches are provided on the rod side and the head side of the cylinder body. Therefore, there is a risk that the heat inside the drying chamber will damage the air tube or cause the reed switch to malfunction, resulting in malfunction. Furthermore, the top plate of the drying chamber is provided with guide holes in the range where the hanging rod reciprocates. An endless heat-resistant shielding belt is movably installed along the inner and outer longitudinal surfaces of the top plate. This heat-resistant shielding belt is made of monomer-cast nylon resin for its heat resistance and ease of processing. However, gaps tend to form between the resin belt and the metal top plate. Furthermore, if the resin belt is configured with a combination of block patterns, gaps tend to form between the block patterns due to the curved posture or flexural deformation of the belt, which can easily cause hot air inside the drying chamber to leak outside. [Means for solving the problem]

[0008] The present invention has been made to solve these problems, and its purpose is to provide a drying device that improves the reliability of the device by stacking and holding carriers on which workpieces are placed without installing a drive source or sensor inside the drying chamber, thereby preventing breakdowns and malfunctions due to heat damage.

[0009] In order to achieve the above object, the present invention has the following configuration. A drying apparatus in which workpieces are sequentially dried in a predetermined temperature profile while being transported within a drying chamber while held on a carrier, the drying apparatus comprising: a plurality of lifting mechanisms for raising and lowering the carrier on which the workpieces are placed within the drying chamber; and a work transfer mechanism in which a work holding section for holding and transporting the workpieces between the lifting mechanisms is suspended and supported by a hanging rod on a top plate section of the drying chamber; the plurality of lifting mechanisms include a first lifting mechanism for stacking the carrier on which the workpieces are placed while lifting it from the bottom of the drying chamber toward the top plate section; and a second lifting mechanism for stacking the workpieces by the work transfer mechanism. The drying chamber is provided with at least one pair of second lifting mechanisms which are sequentially transferred from one lifting mechanism and lowered to stack the carriers, and the first lifting mechanism and the second lifting mechanism have first holding claws or second holding claws which hold a predetermined number of carriers by supporting the carrier stack, in which a predetermined number of carriers are stacked, at both side edges within the drying chamber, and are supported by hanging them around a pivot axis on a claw support member laid vertically within the drying chamber, and the first holding claws or second holding claws are each opened and closed by a drive transmitted from a drive source located outside the drying chamber and thermally isolated from the bottom of the drying chamber.

[0010] The first lifting mechanism lifts the carrier carrying the workpieces from the bottom of the drying chamber toward the top plate while stacking them, and the second lifting mechanism lowers the topmost workpiece transferred from the first lifting mechanism by the work transfer mechanism while stacking them, and the first holding claw or the second holding claw is opened and closed by a drive source located outside the drying chamber and thermally insulated from the bottom of the drying chamber. This prevents the drive source from breaking down or malfunctioning due to heat damage in the drying chamber, improving the reliability of the device.

[0011] a lifting rod connected to the drive source and extending vertically within the drying chamber, the lifting rod being arranged parallel to the claw support member within the drying chamber; and a claw opening / closing mechanism in which the first holding claw or the second holding claw and the lifting rod are connected by a link, The aforementioned nail Opening and closingThe mechanism may be configured such that when the first holding claw or the second holding claw is closed, it holds the carrier stack, and when it is opened it allows carriers to be stacked on the carrier stack. This allows the first holding claw or the second holding claw to be opened and closed simultaneously using the claw opening and closing mechanisms provided on the first lifting mechanism and the second lifting mechanism, respectively, to carry out drying work while stacking carriers sequentially on the carrier stack, thereby improving workability.

[0012] The drying chamber includes the first lifting mechanism and the second lifting mechanism. of The claw opening / closing mechanism is provided on each side of the carrier stack to be lifted and lowered, and includes a pair of the claw support member and the lifting rod connected to the drive source. Record number The first holding claw and the second holding claw may be arranged at a predetermined interval with respect to the claw support member so as to support an equal number of stacked carriers. This allows the number of carriers in the carrier stack to be raised and lowered by the first lifting mechanism and the second lifting mechanism to be adjusted as desired, and by holding an equal number of carrier stacks in each of the first and second holding claws, weight balance can be easily achieved.

[0013] The drying chamber may include a carrier loading mechanism that loads a carrier carrying a workpiece from a work supply position outside the drying chamber to a first position below a first lifting mechanism inside the drying chamber and hands it over to the lowest layer of the carrier stack, a carrier unloading mechanism that receives the carrier carrying a workpiece from the lowest layer of the carrier stack at a second position below a second lifting mechanism inside the drying chamber and loads it to a work removal position outside the drying chamber, and a carrier circulation mechanism that returns the carrier from which the workpiece has been removed from the work removal position to the work supply position for reuse. In this way, the carrier carry-in mechanism carries the carrier K carrying the undried workpieces into the drying chamber and hands it over to the first lifting mechanism, and the carrier carry-out mechanism receives the carrier carrying the dried workpieces from the second lifting mechanism and carries it out of the drying chamber. This repeating the operation improves work efficiency. In addition, the carrier return mechanism returns the empty carrier from the work removal position to the work supply position for reuse, thereby shortening the takt time and improving work efficiency.

[0014] The carrier loading mechanism and the carrier unloading mechanism are Note At the second position, lifters may be provided that support the respective carrier stacks and are capable of moving up and down. As a result, when the first holding claw opens, the carrier loading mechanism supports the carrier stack using the lifter at the first position, and when the second holding claw opens, the carrier unloading mechanism supports the carrier stack at the second position, allowing for smooth transfer of a new carrier or removal of a carrier after drying.

[0015] A guide hole is provided in the top plate portion within the range in which the hanging rod of the work transfer mechanism reciprocates, and an endless heat-resistant shielding belt is arranged on the outer surface of the top plate portion overlapping the guide hole and movable along the longitudinal direction, the hanging rod is inserted into the belt portion of the heat-resistant shielding belt that overlaps the guide hole, and when the work transfer mechanism is operated and the hanging rod moves from one end side to the other end side of the guide hole, it is preferable that the heat-resistant shielding belt rotates in response to the movement, thereby constantly blocking the guide hole. As a result, even when the hanging rod of the work transfer mechanism moves along the guide hole to transfer the work between the lifting mechanisms, the heat-resistant shielding belt rotates while remaining overlapped on the outer surface of the top plate portion, constantly blocking the guide hole, thereby preventing hot air from leaking out of the drying chamber through the guide hole and improving thermal efficiency.

[0016] The top plate DepartmentThe resin plates may be overlapped along the long holes provided in the longitudinal direction of the resin plate, and the metal heat-resistant shielding belt may slide on the resin plates while overlapping so as to close the long holes. This allows the metal top plate Department Since the metal heat-resistant shielding belt is not directly placed on top of the resin plate, the heat-resistant shielding belt slides on the resin plate, so there is no risk of dust generation and hot air is less likely to leak. [Effects of the Invention]

[0017] By using the drying device described above, the carriers carrying the workpieces can be stacked and held without installing a drive source or sensor inside the drying chamber, thereby preventing breakdowns and malfunctions caused by heat damage to the drive source and improving the reliability of the device. Furthermore, it is possible to provide a drying device that can prevent hot air from leaking out of the drying chamber and maintain a stable indoor temperature. [Brief explanation of the drawings]

[0018] [Figure 1] 1A and 1B are a front view, a right side view, a front perspective view, a right side perspective view, a plan perspective view, and a front view of the control panel of the drying device and the hot air generating device, respectively. [Figure 2] FIG. 1E is an enlarged perspective view of the right side of the drying device of FIG. 1D. [Figure 3] FIG. 2 is a front perspective view of the drying device body. [Figure 4] 4 is an explanatory diagram of a first lifting mechanism and a second lifting mechanism disposed in a drying chamber of the drying device main body of FIG. 3. FIG. [Figure 5] 5A and 5B are a front view and a right side view of the pawl opening / closing mechanism alone in FIG. 4. [Figure 6] 4 is a plan view showing the bottom of a drying chamber indicated by an arrow AA in the drying device of FIG. 3. FIG. [Figure 7] 3 is a front explanatory perspective view of the internal configuration of a workpiece transfer mechanism provided on the top plate of the drying chamber in FIG. 2. FIG. [Figure 8] 8A and 8B are a plan view and a front view of the work transfer mechanism of FIG. 7. [Figure 9]1A is a plan view, a front perspective view, and a right side perspective view of a carrier. [Figure 10] FIG. 10 is a rear view of the carrier of FIG. 9. [Figure 11] FIG. 10 is a perspective view of the carrier plates stacked on top of each other. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, an embodiment of a drying device according to the present invention will be described with reference to the accompanying drawings. In this embodiment, a drying device used in a manufacturing process of semiconductor parts to which, for example, resin is supplied as a workpiece W will be described as an example.

[0020] The schematic configuration of the drying device 1 will be described with reference to FIG. First, the overall configuration of the drying apparatus 1 will be described with reference to FIGS. 1A to 1F. As shown in FIG. 1A, a workpiece W transported on a transport line (not shown) is transferred by a supply hand 1a onto a carrier K at a workpiece supply position P (see FIG. 1E) (see FIGS. 1C and 1E). The drying apparatus main body 2 is equipped with a drying chamber 2a (drying furnace). The carrier K with the workpiece W loaded at the workpiece supply position P is carried into the drying chamber 2a, where the workpiece W is dried according to a predetermined temperature profile while being transported within the drying chamber 2a. After drying, the carrier K with the workpiece W loaded thereon is carried to a workpiece removal position Q (see FIG. 1E) and removed from the carrier K by the removal hand 1c (see FIGS. 1C and 1E). A hot air generator 3 is connected to the drying apparatus main body 2. The hot air generator 3 has a heater as a heat source, a blower as an air blower, a HEPA filter, etc., and generates hot air at a predetermined temperature and circulates it between the drying chamber 2a and the drying chamber 2a.

[0021] As shown in Figure 1D, the hot air generator 3 and the dryer main body 2 are connected by a blower duct 3a and an inlet duct 3b. Hot air generated by the hot air generator 3 is sent to the top of the drying chamber 2a through the blower duct 3a, and then circulated from the bottom of the drying chamber 2a through the inlet duct 3b (see Figure 1E) to the hot air generator 3. The bottom of the drying chamber 2a is open, but a horizontal air curtain provides thermal insulation from the space below, where the drive source for the pawl opening / closing mechanism (described later) is located. Also, as shown in Figures 1E and 1F, a separate control panel 4 is provided to control the heating operation of the hot air generator 3. As shown in Figures 1A and 1C, a control panel 2b equipped with various operation keys, function keys, a display monitor, and the like is located on the front of the dryer main body 2.

[0022] The configuration of each part of the drying device 1 will be described with reference to FIG. At the work supply position P, a supply hand 1a for gripping a workpiece W is provided so as to be able to open and close. The supply hand 1a grips a resin-coated workpiece W transported from a transport line (not shown) and transfers it to a carrier K located at the supply position. The supply hand 1a is capable of scanning by drive mechanisms provided in the X-, Y-, and Z-axis directions, respectively. In FIG. 2, once the workpiece W is transferred from the supply hand 1a to the carrier K set at the work supply position P, the carrier K is transported into the first lifting mechanism 7a in the drying chamber 2a by a carrier carry-in mechanism 14a (described later). Furthermore, the carriers K stacked by the second lifting mechanism 7b in the drying chamber 2a are transported to the work removal position Q by a carrier removal mechanism 14b (described later), and the dried workpiece W placed on the carrier K is removed by the removal hand 1b. Like the supply hand 1a, the removal hand 1b is also capable of scanning by drive mechanisms provided in the X-, Y-, and Z-axis directions, respectively.

[0023] As shown in Fig. 1C, the drying apparatus main body 2 is provided with a plurality of lifting mechanisms (first lifting mechanism 7a and second lifting mechanism 7b) that raise and lower the carrier K on which the workpiece W is placed within the drying chamber 2a, and the top plate 5 of the drying chamber 2a is provided with a work transfer mechanism 6 in which a carrier holding part 6a that holds and transfers the carrier K between the lifting mechanisms is suspended and supported by a hanging rod 6b. As shown in Fig. 3, the lifting mechanism includes at least one pair of first lifting mechanism 7a that stacks the carrier K on which the workpiece W is placed while lifting it from the bottom of the drying chamber 2a toward the top plate 5, and second lifting mechanism 7b that stacks the topmost workpiece W by the work transfer mechanism 6 while lowering it.

[0024] 4, a total of eight claw support members 8 are installed vertically in the drying chamber 2a, one pair (four on each side) on the left and right sides of the carrier K that is raised and lowered by the first lifting mechanism 7a and the second lifting mechanism 7b. Each claw support member 8 of the first lifting mechanism 7a has a plurality of first holding claws 9a suspended about a rotation shaft using an L-shaped angle bar, and each claw support member 8 of the second lifting mechanism 7b has a plurality of second holding claws 9b suspended about a rotation shaft using an L-shaped angle bar.

[0025] As shown in Figures 5A and 5B, the claw opening / closing mechanisms 12a and 12b open and close the first holding claws 9a and the second holding claws 9b provided corresponding to the first lifting mechanism 7a and the second lifting mechanism 7b, respectively. Four air cylinders 10 (drive sources) are provided below (outside) the bottom of the drying chamber 2a, corresponding to the first lifting mechanism 7a and the second lifting mechanism 7b, respectively. As shown in Figure 4, four lifting rods 11a and 11b are connected to the air cylinders 10 and extend vertically movably within the drying chamber 2a, and are each disposed parallel to the claw support member 8 within the drying chamber 2a. The claw ends of the first holding claws 9a or the second holding claws 9b are connected to the lifting rods 11a and 11b by bendable links 13a and 13b, respectively. In addition, in Figure 5A, the lowest first holding claw 9a and second holding claw 9b are in an open state, and the first holding claw 9a and second holding claw 9b above them are in a closed state, but this is for the purpose of explaining the opening and closing operation, and the first holding claw 9a and second holding claw 9b are opened and closed simultaneously in accordance with the lifting and lowering operation of the lifting rods 11a and 11b. The claw opening / closing mechanisms 12a, 12b open and close the first holding claw 9a and the second holding claw 9b provided on both sides of the carrier K by an air cylinder 10 provided outside the drying chamber 2a. As a result, as shown in Fig. 3, the first lifting mechanism 7a and the second lifting mechanism 7b each support a carrier stack in which a predetermined number of carriers K are stacked.

[0026] In the drying device 1, the workpieces W to which the resin has been applied are sequentially dried according to a predetermined temperature profile while the workpieces W are transported within the drying chamber 2a (drying furnace) while being held on the carrier K. Specifically, as shown in Fig. 3, in the drying chamber 2a, the carrier K on which the workpieces W are placed is stacked while being raised from the bottom of the drying chamber 2a toward the top plate 5 by the first lifting mechanism 7a, and the topmost workpiece W together with the carrier K is sequentially transferred from the first lifting mechanism 7a to the second lifting mechanism 7b by the work transfer mechanism 6, and is then lowered while the bottommost workpiece W is removed from the drying chamber 2a, where it is dried.

[0027] 3, the carrier carry-in mechanism 14a carries the carrier K on which the workpiece W is placed from the workpiece supply position P outside the drying chamber 2a to a first position below the first lifting mechanism 7a inside the drying chamber 2a and delivers it to the bottom layer of the carrier stack. Also, the carrier carry-out mechanism 14b receives the carrier K on which the workpiece W is placed from the bottom layer of the carrier stack at a second position below the second lifting mechanism 7b inside the drying chamber 2a and carries it out to the workpiece removal position Q outside the drying chamber 2a.

[0028] As shown in Fig. 2, the carrier carry-in mechanism 14a and the carrier carry-out mechanism 14b each raise and lower a lifter 14d supporting the carrier K using an electric actuator 14c (such as a servo motor). The carrier carry-in mechanism 14a can reciprocate between a work supply position P and a first position within the drying chamber 2a using, for example, a single-shaft electric slider. Similarly, the carrier carry-out mechanism 14b can reciprocate between a work removal position Q and a second position within the drying chamber 2a using a single-shaft electric slider.

[0029] 2, the carrier carry-in mechanism 14a carries the carrier K carrying the workpiece W on the lifter 14d into the drying chamber 2a from the work supply position P, and then, at a first position below the first lifting mechanism 7a, the electric actuator 14c raises the lifter 14d to transfer the workpiece W to the lowest layer of the carrier stack. The carrier carry-out mechanism 14b receives the carrier K carrying the workpiece W on the lowest layer of the carrier stack on the lifter 14d at a second position below the second lifting mechanism 7b in the drying chamber 2a, and removes it to the work removal position Q outside the drying furnace 2a. This allows the carrier carry-in mechanism 14a to repeatedly transfer the carrier K carrying the workpiece W to the first lifting mechanism 7a and then receive the carrier K carrying the dried workpiece W from the second lifting mechanism 7b to the carrier carry-out mechanism 14b, thereby improving work efficiency. The carrier K is taken out to the workpiece take-out position Q outside the drying chamber 2a, and the dried workpiece W is taken out by the take-out hand 1b and transported to the next process. In addition, the empty carrier K from which the workpiece W has been taken out is handed over from the lifter 14d of the second carrier carry-out mechanism 14b to the carrier return mechanism 15 (described later) and transported to the workpiece supply position P.

[0030] As shown in Fig. 2, a carrier return mechanism 15 is provided below the work supply position P and the work unloading position Q outside the drying chamber 2a, which returns the carrier K from the work unloading position Q to the work supply position P for reuse. The carrier return mechanism 15 returns the empty carrier K received at the work unloading position Q to the work supply position P by a conveyor transport device. Then, the lifter 14d of the carrier carry-in mechanism 14a is raised to receive the empty carrier K (see Fig. 2), and a new work W is supplied by the supply hand 1a (see Fig. 1C).

[0031] As a result, the carrier carry-in mechanism 14a carries the carrier K with the workpiece W before drying placed thereon from the workpiece supply position P into the drying chamber 2a and holds it on the first lifting mechanism 7a, and the carrier carry-out mechanism 14b receives the carrier K with the dried workpiece W placed thereon at a second position in the drying chamber 2a and takes it out to the workpiece removal position Q. In addition, the carrier return mechanism 15 returns the empty carrier K from the workpiece removal position Q to the workpiece supply position P, and this operation is repeated for reuse. This makes it possible to shorten the takt time and improve work efficiency.

[0032] As shown in Fig. 3, a work transfer mechanism 6 is provided on the top plate 5 of the drying chamber 2a, which transfers the workpiece W together with the carrier K from the first lifting mechanism 7a to the second lifting mechanism 7b. The work transfer mechanism 6 has a carrier holding part 6a that holds and transfers the carrier K on which the workpiece W is placed, and is supported by a hanging rod 6b.

[0033] In FIG. 7, the workpiece transfer mechanism 6 includes a drive mechanism 6c for the workpiece holder 6a on the upper surface (outer surface) of the top plate 5. An electric actuator or the like is preferably used as the drive mechanism 6c. A servo motor, for example, serves as a drive source, rotates a ball screw forward and backward, causing a slider 6d, connected to the ball screw via a nut, to reciprocate along a pair of linear rails 6e provided on the top plate 5. A pair of lifting cylinders 6f are supported on the slider 6d. The tips of the cylinder rods 6g of the pair of lifting cylinders 6f are connected to movable plates 6h, respectively. When the lifting cylinders 6f are operated, the cylinder rods 6g extend and retract, causing the movable plates 6h to move up and down between the top plate 5 and the slider 6d. The upper ends of a pair of hanging rods 6b are suspended and supported by the movable plate 6h (see FIG. 8B). The pair of hanging rods 6b are inserted through guide holes 5a (long holes) provided in the top plate 5 and extend into the drying chamber 2a. The lower ends of these hanging rods 6b are connected to the center of a horizontal support plate 6i. As shown in Fig. 8B, carrier holding units 6a are suspended and supported at four locations on the horizontal support plate 6i. Each carrier holding unit 6a has hanging holding rods 6a1, each of which has an L-shaped hook 6a2 at the lower end. The holding rods 6a1 are inserted into four through-holes K1 provided on the outer edge of the carrier K shown in Fig. 8A, and the hooks 6a2 are engaged with the engaging holes K2, so that the carrier holding unit 6a can hold the topmost carrier K of the first lifting mechanism 7a and transport it to the second lifting mechanism 7b.

[0034] 8A and 8B, an endless heat-resistant shielding belt 16 is disposed on the outer surface of the top plate 5, overlapping the guide hole 5a and movable along the longitudinal direction. A metal belt (e.g., a stainless steel belt) with a thickness of approximately 0.1 to 0.2 mm is used as the heat-resistant shielding belt 16. A pair of hanging rods 6b suspended from a movable plate 6h penetrates the top plate-side belt portion 16a of the endless heat-resistant shielding belt 16 and is supported suspended thereon. A resin plate 17 is placed over the guide hole 5a provided in the longitudinal direction of the top plate 5. The resin plate 17 has a slot 17a that includes the guide hole 5a. The resin plate 17 is fixed to the top plate 5 along the slot 17a on both sides in the lateral direction. The metal heat-resistant shielding belt 16 slides over the resin plate 17 while overlapping it so as to close the guide hole 5a and the slot 17a. The top-plate-side belt portion 16a, which is superimposed on the resin plate 17, is held down by a pair of pressure plates 18 from both side openings of the heat-resistant shielding belt 16 to prevent it from floating up on the resin plate 17. Also, as shown in FIG. 7, a color ring 19 is fitted directly above the elongated hole 17a through which the hanging rod 6b passes, holding the heat-resistant shielding belt 16 down on the resin plate 17 and preventing hot air from leaking through the elongated hole 17a that communicates with the guide hole 5a. Monomer cast nylon resin (registered trademark: MC nylon) or the like is used for the resin plate 17 because of its heat resistance and ease of processing. The hanging rod 6b, which supports the carrier holding portion 6a, is provided penetrating the top-plate-side belt portion 16a of the circulating heat-resistant shielding belt 16 and is connected to be movable along the guide hole 5a and the elongated hole 17a. In addition, the cylinder rod 6g connected to the movable plate 6h is disposed outside the heat-resistant shielding belt 16, so that it does not interfere with the heat-resistant shielding belt 16.

[0035] The work transfer mechanism 6 raises and lowers the work holding portion 6a using the lifting cylinder 6f, and slides the slider 6d using the drive mechanism 6c to move the work holding portion 6a in the space above the drying chamber 2, thereby transferring the carrier K carrying the work W from the first lifting mechanism 5 side to the second lifting mechanism 7 side, as will be described later. At this time, when the work transfer mechanism 6 is operated and the hanging rod 6b moves from one end side to the other end side of the guide hole 5a, the heat-resistant shielding belt 16 is rotated to constantly block the guide hole 5a and the elongated hole 17a.

[0036] As a result, even when the hanging rod 6b of the work transfer mechanism 6 moves along the guide hole 5a of the top plate portion 5 to transfer the work W between the lifting mechanisms, the heat-resistant shielding belt 16 rotates while being superimposed on the outer surface of the top plate portion 5, constantly blocking the guide hole 5a, thereby preventing hot air from leaking out of the drying chamber 2a through the guide hole 5a and improving thermal efficiency. Furthermore, since the metal heat-resistant shielding belt 16 is not directly superimposed on the metal top plate portion 5, the heat-resistant shielding belt 16 slides on the resin plate 17, and there is no risk of dust generation.

[0037] As shown in Figures 9A-C and 10, a rectangular carrier K on which a workpiece W is placed has a total of four through-holes K1 formed near its four corners, into which holding rods 6a1 are inserted. The holding rods 6a1 are inserted into the through-holes K1 and the hooks 6a2 are engaged with the engaging holes K2, thereby holding the carrier K with the workpiece W placed thereon and transporting it from the first lifting mechanism 7a to the second lifting mechanism 7b. Four punched holes K3 are formed in the carrier K, and positioning pins K4 for positioning the workpiece W are provided around the punched holes K3. Spacers K5 protrude from each of the four corners of the carrier K. A mating pin K6 protrudes from the upper portion of each spacer K5 via a resin portion K5a, and a pin hole K7 for mating with the mating pin K6 is provided at the lower portion (see Figure 10). As shown in Figure 11, carriers K are connected to each other by fitting pins K6 into pin holes K7 at the four corner spacers K5, allowing the workpieces W to be stacked and supported without contact with each other. Furthermore, since carriers K are stacked on top of each other via the resin parts K5a, there is no risk of dust being generated when carriers K are stacked on top of each other.

[0038] 4, the claw opening / closing mechanisms 12a, 12b open and close the first holding claw 9a and the second holding claw 9b that are suspended and supported by a claw support member 8 fixed to the drying chamber 2a. Four lifting rods 11a, 11b connected to four air cylinders 10 (drive sources) that are provided outside the drying chamber 2a (below the bottom of the drying chamber 2a) extend vertically in parallel with the claw support member 8 within the drying chamber 2a.

[0039] As shown in Figures 5A and 5B, the claw ends of the first holding claw 9a or the second holding claw 9b are connected to the lifting rods 11a, 11b by a plurality of bendable links 13a, 13b, respectively. When the air cylinder 10 is stationary, the first holding claw 9a and the second holding claw 9b hang down and hold the carrier K on both sides (see Figure 4). When the air cylinder 10 is activated, the lifting rods 11 rise into the drying chamber 2a, the plurality of links 13a, 13b are folded, and the tips of the first holding claw 9a and the second holding claw 9b move close to the claw support member 8 (see Figure 5A). As a result, the first holding claw 9a and the second holding claw 9b are opened on both sides of the carrier K, opening the carrier K. When the carriers K are released, the carrier carry-in mechanism 14a and the carrier carry-out mechanism 14b support the lowest carrier K with a lifter 14d that supports the carrier K with an electric actuator 14c (see FIG. 2).

[0040] In Figure 4, an air tube (not shown) is connected to the air cylinder 10, and a position sensor 10a such as a reed switch is provided. The drying chamber 2a and the space below its bottom are thermally insulated by an air curtain, so the temperature of the drying chamber 2a does not drop. Hot air sent from the hot air generator 3 to the top of the drying chamber 2a through the air duct 3a is sucked in by multiple suction ducts 3b opening at the bottom of the drying chamber 2a, as shown in Figure 6, and circulated to the hot air generator 3. Therefore, even if the drive source is provided with, for example, the air cylinder 10 and a position sensor 10a such as a reed switch, there is no risk of breakdown or malfunction due to heat damage, and the reliability of the device is improved.

[0041] Moreover, the first holding claws 9a and the second holding claws 9b are arranged at a predetermined interval with respect to the claw support member 8 so as to support an equal number of carrier stacks. This makes it possible to arbitrarily adjust the number of carriers K of the carrier stack to be lifted and lowered by the first lifting mechanism 7a and the second lifting mechanism 7b, and also makes it possible to easily achieve a uniform weight balance by holding an equal number of carrier stacks on the first holding claws 9a and the second holding claws 9b, respectively.

[0042] Here, we will explain the operation of transporting the workpiece W to the drying chamber 2. The workpiece W is, for example, a substrate on which electronic components have been mounted in a previous process and to which a resin layer has been applied. As shown in Figure 2, the carrier K set at the workpiece supply position P is supported on the lifter 14d of the carrier carry-in mechanism 14a, and the workpiece W is supplied by the supply hand 1b of the workpiece supply unit 1a.

[0043] Next, the carrier carry-in mechanism 14a is moved from the work supply position P to a first position directly below the first lifting mechanism 7a in the drying chamber 2a. Then, the electric actuator 14c is operated to raise the lifter 14d, and the carrier K on which the work W is placed is pushed up toward the lowest carrier K in the carrier stack. When the engagement pin K6 of the spacer K5 of the carrier K positioned one level above it engages with the pin hole K7, the air cylinder 10 of the claw opening / closing mechanism 12a shown in Figure 3 is operated to raise the lifting rod 11a, and the hook-shaped first holding claw 9a hooked on the lower part of the carrier K is rotated in a direction away from the carrier K, thereby releasing support for the carrier stack. Once the carrier carry-in mechanism 14a has raised the carrier K by the height of one carrier K, the lifting rod 11a is lowered and the first holding claw 9a is rotated in a direction approaching the lowest carrier K, thereby supporting the carrier stack above again. The carrier carry-in mechanism 14a lowers the lifter 14d and returns from the first position to the work supply position P outside the drying chamber 2a, ready for the next work supply. By repeating the above operations, carriers K carrying the work W are sequentially stacked and supported by the first lifting mechanism 7a.

[0044] As described above, the uppermost carrier K stacked and supported by the first lifting mechanism 7a is held by the workpiece holding portion 6a of the workpiece transfer mechanism 6 and delivered to the uppermost side of the carrier stack provided on the adjacent second lifting mechanism 7b. With the carrier stack supported by the lifter 14d of the carrier discharge mechanism 14b, the lifting rod 11b is raised by the air cylinder 10 to open the second holding claws 9b in a direction away from the carrier K, and the carrier K is stacked on the uppermost layer of the carrier stack. In this state, the second holding claws 9b are moved close to the carrier K and closed, whereby the carrier stack is held by the second holding claws 9b.

[0045] By repeating the carrier transfer operation by the work transfer mechanism 6, a stack of carriers is supported in a stack on the second lifting mechanism 7 side. When carriers K supporting a predetermined number of works W are stacked and supported on the second lifting mechanism 7, the lifter 14d of the carrier discharge mechanism 14b rises and presses up against the lowest carrier K in the stack of carriers. When the lifter 14d presses up against the lowest carrier K, the claw opening / closing mechanism 12b shown in FIG. 4 is activated. That is, the air cylinder 10 is activated to rotate the hook-shaped second holding claw 9b hooked on the bottom of the carrier K in a direction away from the carrier K, temporarily releasing the support of the stack of carriers. The lifter 14d is lowered by one carrier K, and then the claw opening / closing mechanism 12b is again activated to rotate the second holding claw 9b in a direction toward the carrier K one carrier above the lowest carrier K, thereby again supporting the stack of carriers stacked above it. The carrier carry-out mechanism 14b carries the lowest carrier K, on which the dried workpieces W are placed, from the second position in the drying chamber 2a to the workpiece take-out position Q while it remains handed over to the lifter 14b. Then, at the workpiece take-out position Q, the take-out hand 1c takes out the workpiece W from the carrier K. The carrier carry-out mechanism 14b lowers the lifter 14d supporting the empty carrier K to transfer it to the conveyor device of the carrier return mechanism 15, and the carrier return mechanism 15 transports the empty carrier K from the workpiece take-out position Q to a position below the workpiece supply position P. Then, the lifter 14d of the carrier carry-in mechanism 14a is raised to receive the carrier K, and the carrier waits at the workpiece supply position P until a new workpiece W is supplied. The above operations are repeated.

[0046] By repeating the above operations, the carrier K carrying the workpiece W is repeatedly transported within the drying chamber 2a. The lifting operation of the carrier K on the first lifting mechanism 7a side and the lowering operation of the carrier K on the second lifting mechanism 7b side may be performed in parallel or successively. Furthermore, the first lifting mechanism 7a (carrier lifting side) and the second lifting mechanism 7b (carrier lowering side) provided in the drying chamber 2a are not limited to a pair, and multiple pairs may be provided if the drying time can be adjusted as desired. [Explanation of symbols]

[0047] DESCRIPTION OF SYMBOLS W Work K Carrier K1 Through hole K2 Locking hole K3 Drilled hole K4 Positioning pin K5 Spacer K5a Resin part K6 Fitting pin K7 Pin hole 1 Drying device 1a Work supply part 1b Supply hand 1c Take-out hand 2 Drying device main body 2a Drying chamber 2b Operation panel 3 Hot air generator 3a Air supply duct 3b Intake duct 4 Control panel 5 Top plate part 6 Work transfer mechanism 6a Carrier holding part 6a1 Holding rod 6a2 Hook part 6b Hanging rod 6c Drive mechanism 6d Slider 6e Linear rail 6f Lifting cylinder 6g Cylinder rod 6h Movable plate 6i Horizontal support plate 7a First lifting mechanism 7b Second lifting mechanism 8 Claw support member 9a First holding claw 9b Second holding claw 10 Air cylinder 11a, 11b Lifting rod 12a, 12b Claw opening / closing mechanism 13a, 13b Link 14a Carrier loading mechanism 14b Carrier unloading mechanism 14c Electric actuator 14d Lifter 15 Carrier returning mechanism 16 Heat-resistant shielding belt 17 Resin plate 17a Elongated hole 18 Pressing plate 19 Color ring

Claims

1. A drying apparatus in which workpieces are sequentially dried at a predetermined temperature profile while being transported in a drying chamber while being held by a carrier, a plurality of lifting mechanisms for lifting and lowering the carrier on which the workpiece is placed within the drying chamber; a work transfer mechanism in which a work holding section that holds and transfers a work between the lifting mechanisms is suspended and supported by a suspension rod, the work transfer mechanism being provided on a top plate section of the drying chamber; the plurality of lifting mechanisms include at least one pair of a first lifting mechanism that stacks the carrier on which the workpieces are placed while lifting it from the bottom of the drying chamber toward the top plate portion, and a second lifting mechanism that stacks the workpieces while lowering the uppermost workpieces that are sequentially transferred from the first lifting mechanism by the workpiece transfer mechanism, The first lifting mechanism and the second lifting mechanism each have a first holding claw or a second holding claw that holds a predetermined number of carriers by supporting a carrier stack in the drying chamber at both side edges, and are each suspended and supported around a pivot axis by a claw support member laid vertically in the drying chamber, and the first holding claw or the second holding claw is opened and closed by a drive power transmitted from a drive source located outside the drying chamber and thermally isolated from the bottom of the drying chamber.

2. 2. The drying device according to claim 1, further comprising: a lifting rod connected to the drive source and extending vertically within the drying chamber, the lifting rod being arranged parallel to the claw support members within the drying chamber; and a claw opening / closing mechanism in which the first holding claw or the second holding claw is connected to the lifting rod by a link, the claw opening / closing mechanism holding the carrier stack when the first holding claw or the second holding claw is closed, and allowing carriers to be stacked on the carrier stack when the first holding claw or the second holding claw is opened.

3. 3. The drying device according to claim 2, wherein the drying chamber is provided with a pair of claw opening / closing mechanisms, each equipped with a lifting rod connected to the claw support member and the drive source, on both sides of the carrier stack that raises and lowers the first lifting mechanism and the second lifting mechanism, and the first holding claws and the second holding claws are arranged at a predetermined interval relative to the claw support members so as to support an equal number of stacked carriers.

4. a carrier carry-in mechanism that carries a carrier on which a workpiece is placed from a workpiece supply position outside the drying chamber to a first position below a first lifting mechanism inside the drying chamber and delivers the carrier to the lowest layer of the carrier stack; and a carrier carry-out mechanism that receives the carrier on which the workpiece is placed from the lowest layer of the carrier stack at a second position below a second lifting mechanism inside the drying chamber and carries the carrier to a workpiece removal position outside the drying chamber.

3. The drying apparatus according to claim 1, further comprising a carrier circulation mechanism for returning the carrier from which the workpiece has been removed from the workpiece removal position to the workpiece supply position for reuse.

5. 5. The drying device according to claim 4, wherein the carrier loading mechanism and the carrier unloading mechanism each include a lifter that can be raised and lowered to support the carrier stack at the first position or the second position.

6. A guide hole is provided in the top plate portion within a range in which a hanging rod reciprocates, and an endless heat-resistant shielding belt is arranged so as to overlap the guide hole in the top plate portion and be movable along the longitudinal direction, and the hanging rod is inserted into the belt portion of the heat-resistant shielding belt that overlaps the guide hole, 3. The drying device according to claim 1, wherein when the workpiece transport mechanism is operated to move the hanging rod from one end side to the other end side of the guide hole, the heat-resistant shielding belt rotates in response to the movement to close the guide hole.

7. 7. The drying device according to claim 6, wherein resin plates are stacked along a long hole provided in the longitudinal direction of the top plate portion, and the metal heat-resistant shielding belt slides on the resin plates while being stacked so as to close the long hole.

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