JP3855115B2 - Solder reflow equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solder reflow apparatus for soldering electronic components or the like to a printed circuit board, for example.
[0002]
In this specification, front, rear, left, and right are based on FIG. 3, and the right in FIG. 3 is the front, the left is the rear, the upper is the right, and the lower is the left.
[0003]
[Prior art]
A conventional solder reflow apparatus includes a furnace provided in an exterior panel and a chain conveyor provided in the exterior panel with a space left and right, and an upper conveyance path portion thereof penetrating the furnace.
[0004]
[Problems to be solved by the invention]
In the case of the above-described solder reflow device, metal powder or the like is generated when the chain roller and the chain plate of the chain conveyor and the chain rail come into contact with each other when the board is conveyed. On the other hand, miniaturization of the circuit on the board has progressed today, and in the future, the metal powder generated when the board is transported will adhere to the board when soldering the electronic parts to the board, and the circuit may be short-circuited or defective. Is expected to cause For this reason, the reflow apparatus which can maintain the high cleanliness which does not generate | occur | produce metal powder at the time of board | substrate conveyance is requested | required.
[0005]
The object of the present invention is to provide a solder reflow apparatus that solves the above-mentioned problems, can maintain a clean atmosphere in the furnace without generating metal powder during substrate transportation, and can be used in a clean room. There is to do.
[0006]
[Means for Solving the Problems and Effects of the Invention]
In order to solve the above-mentioned problems, the solder reflow apparatus of the present invention has a pair of beams that are provided in the left-right direction and extend in the front-rear direction and pass through the furnace in a non-contact manner. By moving in the direction, the substrate is transported in a non-contact and non-sliding manner in the furnace while replacing the substrate with left and right beams.
[0007]
In this solder reflow device, the beam penetrates the furnace in a non-contact manner and conveys the substrate without sliding, so metal powder is not generated in the furnace and the atmosphere in the furnace is kept clean. Can do.
[0008]
The reflow apparatus includes a plurality of substrate support members extending inward in the left-right direction and spaced apart in the front-rear direction from each beam, and the substrate is placed on the substrate support member. There is.
[0009]
In this reflow apparatus, a substrate having a length longer than the interval between adjacent support members in the left beam can be supported. Further, even if the width of the substrate is longer than the length of the support member, the substrate can be supported, and the degree of freedom of the size of the substrate that can be transported is increased.
[0010]
Further, it is preferable that each beam moves in the front-rear direction.
[0011]
In this solder reflow device, the distance of movement of each beam can be reduced, and the length of the solder reflow device can be reduced. In this reflow device, both front and rear ends are open, one end is at the substrate entrance, and the other end is at the other end. A cylindrical furnace body serving as a substrate outlet, and a heating device that heats the inside of the furnace, the cylindrical furnace body is configured by combining a plurality of constituent bodies, and the constituent body constitutes a heat insulation that constitutes the furnace body wall And a heat-resistant cover portion that covers at least the heat-insulating side surface of the heat-insulating portion, and the heating device includes an electric heater embedded in a portion closer to the inside of the furnace in the heat-insulating portion constituting the furnace wall of at least one component. A furnace that radiates and heats the substrate may be used.
[0012]
In the furnace in this reflow apparatus, the furnace body can be easily configured by combining the structural bodies, and the furnace inner side surface of the heat insulating part is covered with the heat resistant cover part, so that the airtightness in the furnace can be maintained. In addition, the fine powder generated from the heat insulating portion does not enter the furnace, and the atmosphere in the furnace can be kept clean.
[0013]
Furthermore, the electric heater is embedded in a heat insulating part that constitutes a part of the furnace wall, and since the electric heater is not located in the furnace, the lead wire of the heating device must be installed in the furnace through the inner surface of the furnace body. There is no occurrence of a seal portion between the inner surface of the furnace body and the lead wire.
[0014]
In the furnace in the above reflow apparatus, the heat insulating portion of the structural body may be configured by arranging a plurality of heat insulating materials in the length direction of the furnace body.
[0015]
In this case, a part of the furnace wall can be formed only by arranging the heat insulating materials, and the structure of the furnace becomes simple.
[0016]
In the furnace in the reflow apparatus described above, a black body treatment coating may be applied to at least a portion corresponding to the electric heater on the inner surface of the furnace.
[0017]
Then, the black body treatment coating applied to the inner surface of the furnace body efficiently radiates heat to the substrate, that is, the inner surface of the furnace body becomes a good heat radiating surface, so that temperature interference between the respective parts is reduced.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a solder reflow apparatus according to an embodiment of the present invention will be described with reference to FIGS.
[0019]
The solder reflow apparatus is not shown, for example, an iron plate exterior panel, a furnace (2) disposed in the panel, and disposed in the exterior panel and penetrates the furnace (2) in a non-contact manner. And a so-called walking beam type substrate transfer device (1). Note that the configuration of the exterior panel and the like is the same as a known one that is normally used in a solder reflow apparatus, and detailed description thereof is omitted.
[0020]
The substrate transfer device (1) is provided on a base (6) disposed in the exterior panel, and is provided at a distance from side to side and extends in the front-rear direction, and also has a furnace (2). A pair of left and right beams (3A) (3B) that penetrates in a non-contact manner, and a plurality of substrate support members that extend from the respective beams (3A) (3B) inward in the left-right direction and at equal intervals in the front-rear direction (4A) (4B) and a pair of left and right provided outside the furnace (2) and outside the respective beams (3A) (3B) to move the beams (3A) (3B) in the front-rear direction and the up-down direction Drive device (drive means) (5) and a transmission member (7) connecting the drive device (5) and the beams (3A) (3B) at the front and rear of the beams (3A) (3B) ing.
[0021]
The beams (3A) and (3B) have a hollow cross-sectional shape, and the total length is longer than the length of the furnace (2). The support members (4A) and (4B) are formed in a bar shape that is long in the left and right direction and has a rectangular cross section, and the outer ends in the left and right direction are fixed to the upper surfaces of the beams (3A) and (3B). Further, for example, the spacing between the support members (4A) and (4B) so that the support member (4B) of the right beam (3B) can be positioned between the support members (4A) adjacent to the left beam (3A). Is stipulated.
[0022]
The transmission member (7) has an upper vertical plate-shaped portion, a horizontal plate-shaped portion extending outward in the left-right direction from the lower end portion thereof, and a lower vertical plate-shaped portion extending downward from the tip thereof. The upper end of the plate-like portion is fixed to the outer surface of the beam (3A) (3B), and is connected to the driving device (5) at the lower vertical plate-like portion as will be described in detail later.
[0023]
The left and right drive devices (5) have the same configuration although the left and right directions are different.Hereinafter, the left drive device (5) will be described, and the left drive device (5) in the right drive device (5) will be described. The portions corresponding to) are denoted by the same reference numerals and the description thereof is omitted.
[0024]
The drive device (5) includes a front drive unit (5a) and a rear driven unit (5b) connected to the drive unit (5a) via a connecting rod (8). The drive unit (5a) is a horizontal plate base (10) common to the left and right drive devices (5) fixed on the base (6) and the horizontal plate base (10) from the center in the left-right direction slightly upward from the outside. And a vertical plate-like support member (11) that protrudes and is parallel to the front-rear direction. Two guide members (16) are fixed to the left and right ends of the vertical plate-like support member (11) at intervals in the vertical direction. A vertical plate-like vertical movement member (18) parallel to the front-rear direction is arranged on the left side of the vertical plate-like support member (11), and the guide member (16) is disposed on the front and rear portions of the right surface of the vertical movement member (18). The fixed rail member (17) extending vertically is guided. Thus, the vertically moving member (18) slides up and down while being guided by the rail member (17) and the guide member (16).
[0025]
A crank member (25) is arranged on the left side of the vertical movement member (18). The crank member (25) includes two short and long arms (25b) and (25c) that form an angle of 90 degrees with each other. Further, a shaft member (24 that extends in the left-right direction passes through a vertically long elongated hole (18a) formed in the center of the vertically moving member (18) and the right end is fixed to the vertical plate-like support member (11). The crank member (25) is rotatably supported at the left end of the vertical plate-like support member (11).
[0026]
Rollers (31) that rotate about the horizontal axis are attached to the right end surfaces of the short arm portion (25b) and the long arm portion (25c), respectively. The roller (31) of the short arm portion (25b) is rotatably fitted between horizontal members (26) fixed on the left surface of the vertically moving member (18) with a space in the vertical direction. On the other hand, on the left side of the vertical plate-like support member (11) and below the vertical movement member (18), a vertical plate-like base portion (27a) parallel to the front-rear direction and a vertical plate protruding leftward from the front end thereof A longitudinally-moving member (27) having a cylindrical bracket (27b) is disposed. A nut (27c) is fixed to the bracket (27b). Then, the roller (31) at the tip of the long arm portion (25c) can roll freely between the vertical members (23) fixed to the base portion (27a) of the longitudinal movement member (27) at a distance in the front-rear direction. It is inserted.
[0027]
Two guide members (28) are fixed to the right surface of the plate-like base (27a) of the longitudinally moving member (27) with a space in the front-rear direction. The guide member (28) is guided by a rail member (29) extending in the front-rear direction and fixed to the lower end portion of the vertical plate-like support member (11). Thus, the longitudinally moving member (27) slides back and forth while being guided by the rail member (29) and the guide member (28).
[0028]
A vertical drive motor (12) is fixed to the left rear portion of the horizontal base (10) so that the motor shaft faces the front-rear direction. A screw shaft (13) extending in the front-rear direction is connected to the motor shaft of the motor (12). The screw shaft (13) is screwed onto the nut (27c) via a plurality of balls, and the front end of the screw shaft (13) is a plate-like protrusion (33) fixed to the left front portion of the horizontal base (10) so as to protrude upward. Rotation is supported. Then, when the screw shaft (13) is rotated by the motor (12), the nut (27c) moves back and forth, and as a result, the long arm portion (25c) swings back and forth via the longitudinal movement member (27). The crank member (25) is rotated about the shaft member (24) by being moved. When the crank member (25) rotates, the short arm portion (25b) swings up and down, and the vertical movement member (18) is moved up and down via the horizontal member (26).
[0029]
A rail member (14) extending in the front-rear direction is fixed to the upper left end portion of the vertical movement member (18). The rail member (14) is guided by a guide member (30) fixed to the lower vertical plate-like portion of the transmission member (7). In this way, the transmission member (7) slides back and forth while being guided by the rail member (14) and the guide member (30).
[0030]
A vertical plate-like bracket (19) parallel to the left-right direction is fixed to the transmission member (7) so as to protrude downward. A ball nut (19a) is fixed to the lower end of the bracket (19). On the other hand, a front / rear drive motor (21) is fixed to the rear upper part of the left side surface of the vertical movement member (18) so that the motor shaft faces the front / rear direction. A screw shaft (22) extending in the front-rear direction is connected to the motor shaft of the motor (21). The screw shaft (22) is screwed to the nut (19a) via a plurality of balls, and the front end of the screw shaft (22) is a plate-like protrusion (32) fixed to the front of the vertical movement member (18) so as to protrude leftward. ) Is supported by rotation. Then, when the screw shaft (22) is rotated by the motor (21), the nut (19a) moves back and forth. As a result, the transmission member (7) moves back and forth along the rail member (14) so that the beams (3A) and (3B) move back and forth. As described above, when the vertical movement member (18) moves up and down, the transmission member (7) also moves up and down integrally, and the beams (3A) and (3B) move up and down.
[0031]
The driven portion (5b) is configured by removing the motors (21), (12) and the screw shafts (22), (13) from the drive portion (5a).
[0032]
Next, the furnace (2) will be described with reference to FIGS. The furnace (2) heats the inside of the furnace body (9), that is, the inside of the furnace (2), in which both front and rear ends are open and one end is a substrate inlet and the other end is a substrate outlet. For heating. The cylindrical furnace body (9) is composed of an upper structure body (39) having a substantially concave cross section opened downward and a lower structure body (40) having a substantially concave cross section opened upward. The heating device is arranged in the front-rear direction with a plurality of thick plate upper heater units (34) that are arranged in the front-rear direction and constitute a part of the upper structure body (39), that is, a part of the upper wall of the furnace body (9). And a plurality of thick plate-like lower heater units (35) constituting a part of the lower structure (40), that is, a part of the lower wall of the furnace body (9).
[0033]
As shown in FIG. 5, the left and right side surfaces of the upper structure (39) and the lower structure (40) have vertical parts of the L-shaped member (45) in the cross section, and the upper structure (39) has horizontal parts. In the lower structure (40), the horizontal portions are fixed so as to be positioned on the upper side so as to be positioned on the lower side. The horizontal portions of the upper and lower L-shaped members (45) can be attached to and detached from each other in a state where the upper and lower constituent bodies (39) and (40) are closed by the other constituent bodies (39) and (40). The space surrounded by the upper and lower structures (39) and (40) is a heating space for the substrate (W). The contact surfaces of the upper and lower L-shaped members (45) are sealed by appropriate sealing means (50) such as a gasket. Further, the gap between the upper and lower structures (39) and (40) in the seal portion is a crushing margin of the gasket, and is exaggerated in FIG. 5, but the actual upper and lower structures (39) and (40) are shown. ) Is a slight gap.
[0034]
The upper structure (39) includes a plurality of thick plate-like upper units (34) arranged in the front-rear direction as described above. Then, a substantially arc-shaped heat insulating material (43) having a cross-section extending downward over the entire length of the upper component (39) is fixed to the left and right ends of the upper unit (34). A heat insulating material (42) having the same cross-sectional shape as the unit (34) is fixed to the front end of the front unit (34) and the rear end of the rear unit (34). Thus, all the outer surfaces of the concave body formed by the heat insulating materials (43) and (42) and the upper unit (34) are covered with the metal plate (cover) (41), and the upper structure (39) is formed. ing.
[0035]
As described above, the lower structure (40) includes the thick plate-like lower units (35) arranged in the front-rear direction. A heat insulating material (49) composed of a vertically long rectangular portion and an arc-shaped portion below the lower unit (35) is fixed to the left and right ends of the lower unit (35) so as to protrude upward over the entire length of the lower structure (40). A heat insulating material (44) having the same cross-sectional shape as the unit (35) is fixed to the front end of the front unit (35) and the rear end of the rear unit (35). In this way, the entire outer surface of the concave section formed by the heat insulating materials (49), (44) and the lower unit (35) is covered with the metal plate (cover) (53) to form the lower structure (40). Has been. As described above, the furnace inner surface is covered by the metal plates (41) (53), and the joining portion of the two structural bodies (10) (11) is completely sealed by the sealing means (50), so that a good atmosphere control can be performed. .
[0036]
Next, details of the upper and lower units (34) and (35) will be described. The upper and lower units (34) and (35) have the same shape and configuration although the vertical directions are different. Hereinafter, the lower unit (35) shown in detail in FIG. Members and portions corresponding to the lower unit (35) in the unit (34) are denoted by the same reference numerals, and description thereof is omitted.
[0037]
The lower unit (35) includes, for example, a rectangular parallelepiped heat insulating material (46) mainly composed of ceramic fiber. A corrugated electric heater (47) is embedded in the heat insulating material (46) in the upper portion of the heat insulating material (46), that is, in the furnace inner portion. And all the upper surfaces of the heat insulating material (46) are covered with the mica plate (51) as an insulator. In this unit (35), the electric heater (47) is entirely embedded in the heat insulating material (46), but the electric heater (47) is insulated so that a part of the electric heater (47) is exposed from the heat insulating material (46). An electric heater (47) may be embedded in the material (46). That is, the electric heater (47) only needs to be provided integrally with the heat insulating material (46) , and the configuration of the electric heater (47) and the heat insulating material (41) in the unit (35) is not limited to the above. . For example, as described in Japanese Patent Laid-Open No. 10-12361, an electric heater processed into a waveform having an amplitude larger than the width of the groove is provided in a groove provided on the furnace inner surface of the heat insulating material. The bent portions on both sides in the width direction may be integrally supported by the heat insulating material by entering the heat insulating material from both side walls of the groove.
[0038]
Then, the lower surface of the upper structure (39) in contact with the mica plate (51) of the metal plate (41) is contacted with the mica plate (51) of the metal plate (53) of the lower structure (40). Black body treatment coatings (48) and (52) are respectively applied to the upper surface of the contact portion, that is, the furnace inner surface.
[0039]
Although not shown, the connection terminals of the electric heaters (47) of the units (34) and (35) pass through the metal plates (41) and (53) covering the outer surface of the furnace body (9), and the furnace bodies (9 ) Projects outside and is connected to an appropriate power source.
[0040]
In the solder reflow apparatus configured as described above, the beam (3A) (3B) moves as indicated by the thin arrows in the figure, so that the substrate (W) becomes as indicated by the thick arrows in the figure. It is transported forward, and electronic components are soldered to the board (W) during transport.
[0041]
For example, the support members (4A) and (4B) of the left and right beams (3A) and (3B) are in positions shifted forward and backward. (See FIG. 3) In this state, the substrate (W) to be processed is placed across the plurality of support members (4B) of the right beam (3B). The left and right beams (3A) and (3B) move in the front-rear direction by the same amount.
[0042]
Next, the right beam (3B) advances by a predetermined pitch. On the other hand, the left beam (3A) moves backward by an amount equal to the moving amount of the right beam (3B). Then, the right beam (3B) is lowered and the left beam (3A) is raised, so that the substrate (W) is replaced with the left beam (3A) from the right beam (3B).
[0043]
This time, the left beam (3A) moves forward, and the right beam (3B) moves backward by an equal amount. Next, when the right beam (3B) is raised and the left beam (3A) is lowered, the substrate (W) is replaced from the left beam (3A) to the right beam (3B).
[0044]
The above procedure is sequentially repeated, and the substrate (W) placed on the transfer device (1) advances. Then, the black body treatment coating (48) (52) is heated by the electric heater (47) through the mica plate (51) and the metal plate (41) (53) , and the black body treatment coating (48) (52) The substrate (W) in the furnace body (9) is heated by the emitted infrared rays. The substrate (W) that has been processed is taken out from the substrate transfer device (1) by a carry-out device (not shown). As described above, the substrate (W) is transported in a state of being in contact with only the support members (4A) and (4B), and does not directly contact the furnace body (9), particularly the electric heater (22). Therefore, the temperature of the substrate (W) rises continuously.
[0045]
Further, the left and right beams (3A) and (3B) and the left and right support members (4A) and (4B) do not come into contact with each other during transport of the substrate (W), and dust or the like does not occur. Furthermore, in the transfer device (1), by changing the transfer pitch depending on the length of the substrate (W), it is possible to obtain an optimal transfer speed and an optimal temperature rise curve with respect to the length of the substrate (W). .
[0046]
Note that servo motors may be used as the front and rear and vertical drive motors (12) and (21).
[0047]
In the furnace (2) of the above embodiment, the upper and lower walls of the furnace body (9) are formed by the heater units (34) and (35). A part can be configured, and the configuration becomes simple.
[0048]
In addition, the upper and lower walls of the furnace body (9) are made of a heat insulating material, and the heat transfer cross-sectional area of the cover covering this is extremely small compared to, for example, a muffle, so the remaining heat part and the main heating part are placed in the furnace body (9). Even if it is provided, heat transfer between adjacent portions is small, and a steep temperature gradient peculiar to the furnace used in the reflow apparatus can be obtained in the furnace body (9).
[0049]
In this furnace (2), the furnace body can be divided into upper and lower parts, so that assembly and maintenance can be easily performed.
[0050]
The configuration of each part of the furnace (2) can be changed as appropriate. For example, the entire inner surface of the furnace body (9) may be coated with a black body treatment. Moreover, the heater unit may be provided only in any one of upper and lower sides. Furthermore, it is necessary to cover at least the furnace inner surface with a cover.
[0051]
In the furnace (2) of the above embodiment, a metal plate is used as the cover, but, for example, heat resistant glass may be used as the cover. In this case, good heat radiation characteristics can be obtained without applying a black body treatment coating to the cover.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of a front portion of a board transfer device in a solder reflow apparatus according to an embodiment of the present invention.
FIG. 2 is a vertical sectional view of the transfer device.
FIG. 3 is a plan view of the transfer device.
FIG. 4 is a side view of the transfer device.
FIG. 5 is a cross-sectional view of a furnace in the transfer device.
FIG. 6 is a schematic perspective view of a heater unit constituting the furnace.
[Explanation of symbols]
(1) Transfer device
(2) Furnace
(3A) (3B) Beam
(4A) (4B) Substrate support member
(W) Board

Claims (2)

A pair of beams that are provided at intervals on the left and right, extend in the front-rear direction, and pass through the furnace in a non-contact manner move relatively in the front-rear direction and the up-down direction, so that the substrate is placed on the left and right beams. In the solder reflow apparatus, wherein the substrate is conveyed in the furnace without contact with the furnace inner surface and without sliding,
Solder reflow characterized by comprising a plurality of substrate support members extending inward in the left-right direction from each beam and spaced in the front-rear direction so that the substrate is placed on the substrate support member apparatus. 2. The solder reflow apparatus according to claim 1 , wherein each beam is moved in the front-rear direction.

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