JP6001520B2 - Method for manufacturing turbofan - Google Patents

Description

  The present invention relates to a turbofan molded from a thermoplastic resin that is mounted on an air conditioner, and relates to a turbofan that improves weld assembly and productivity.

  A conventional turbofan is composed of a fan body in which a main plate and a plurality of wings having a bag-like hollow structure having openings on the back side are integrally formed of a thermoplastic resin, and a shroud. Further, each blade of the fan body has a fitting female portion communicating from the blade tip to the blade hollow portion, and a fitting male portion extending from the shroud in the fan height direction at each blade of the shroud. Is formed.

  Then, after the fitting male part of the shroud is inserted into the fitting female part of the fan main body, the blade tip welded part which becomes the inclined surface of the shroud surface and the fan main body and the side of the male male part of the shroud and the fan main body are fitted A side surface of the female portion is fixed and integrated to form a turbo fan. When fixing both the shroud and the fan body formed in this manner, the positioning can be easily and accurately performed by the fitting male part of the shroud and the fitting female part of the fan body, thereby improving the manufacturing accuracy. , Productivity can be improved (see, for example, Patent Document 1).

  The conventional turbofan is configured as described above, and the manufacturing accuracy at the time of fixing the shroud and the fan body is improved, and the productivity can be improved. However, the welding surface between the shroud and the fan main body is the surface of the shroud, the blade tip welded portion that becomes the inclined surface of the fan main body, the side surface of the fitting male portion of the shroud, and the side surface of the female fitting portion of the fan main body. When the fan body is assembled and welded, both are pressurized in the direction of the rotation axis (vertical direction) of the turbofan, but the blade tip welded part of the fan body is inclined in the blade rotation direction, so the blade tip welded part is As a result, the vertical force escapes and a horizontal force is applied to the wing, resulting in a decrease in the welding force, which may result in an uneven welding.

  Also, since the horizontal force is absorbed only by the side of the mating male part of the shroud and the female fitting part of the fan body, stress is concentrated on the mating male part of the shroud and the connecting surface of the shroud. There is a risk of damage.

In order to solve such a problem, a turbo fan and a manufacturing method thereof in Patent Document 2 are proposed and disclosed.
However, the turbofan of the shape of Patent Document 2 has a shape as shown in FIG. Although not shown in FIG. 14, there is a problem that a molding die becomes complicated because the blade portion and the bottom plate of the turbofan are integrally formed. Also, the shroud is provided with the same number of convex fitting portions as the wing portions for firmly joining the wing portions. Therefore, the mold for molding the shroud becomes complicated, and there is a problem that the manufacturing cost increases.

  In the turbofans of Patent Document 1 and Patent Document 2, the main plate and the blade portion are integrated, which makes the mold to be manufactured complicated and increases the cost of the product.

Japanese Patent No. 3509456 JP 2007-120445 A

  In order to solve such problems, the present invention assembles and integrates a main plate, shroud, and blade members (blades) integrated by hollow molding or blow molding, which are components of a turbofan, by ultrasonic welding. A turbofan. According to the present invention, a turbofan can be manufactured without using a complicated mold, and its cost can be significantly reduced.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an inexpensive turbo fan that is more productive than a conventional turbo fan.

  A turbofan according to a first aspect of the present invention for solving the above-described problems is a thermoplastic resin comprising a main plate having a boss fixed to the rotating shaft of a motor at the center, a shroud forming a suction air guide wall, and a plurality of blade members. The main plate has a fitting portion with the plurality of blade members, the shroud has a fitting portion with the plurality of blade members, and the blade member is formed by hollow molding or blow molding. It is a blade member formed so as to be integrated, and the plurality of blade members are fitted in the plurality of fitting portions of the main plate and the shroud in parallel with a rotation axis and integrated by ultrasonic welding. Features.

  According to the first invention, the turbofan is manufactured by separately manufacturing the main plate, the shroud, and the blade member, and the turbofan is fixed by ultrasonic welding. The blade member is integrated by hollow molding or blow molding. The shape of the mold for molding each constituent member is simplified, and the manufacturing cost of the turbofan is significantly reduced. Furthermore, since the constituent members are assembled by ultrasonic welding, the turbofan can be manufactured at a lower cost than the laser welding method. Furthermore, the blade member is integrally formed, and the yield when manufacturing the turbofan can be improved.

  The turbofan of the second invention is the turbofan according to the first invention, wherein the air suction hole formed in the blade member for hollow molding or blow molding of the blade member is a fitting portion of the main plate of the blade member or the shroud. It was provided in the site | part fitted by a fitting part.

  According to the second invention, the air suction hole formed when the blade member is formed by hollow molding or blow molding is a portion where the blade member is fitted in the fitting portion on the main plate side, or the blade is fitted on the shroud side. It is provided in one of the parts fitted into the part. Therefore, since the air suction hole fits in the fitting part of the blade member on the main plate side or the fitting part of the blade member on the shroud side, the hollow space inside the blade member and the outside air are difficult to communicate with each other. Even if the negative pressure side is thin, the strength as a blade member can be maintained.

  A turbofan according to a third invention is characterized in that, in the first invention or the second invention, a welding edge is provided at a fitting portion between the main plate and the blade member and a fitting portion between the shroud and the blade member. And

  According to the third invention, since the welding edge is provided at the portion where the main plate and the shroud are joined to the blade member, ultrasonic welding can be performed without applying an excessive pressure. Therefore, the quality of the turbofan can be ensured and the yield can be improved.

  According to a fourth aspect of the invention, there is provided a turbofan according to any one of the first to third aspects of the invention, wherein the welding edge provided at the fitting portion between the shroud and the blade member extends from the center of the fitting portion to the blade member. It is characterized by being biased toward the positive pressure side or the negative pressure side.

  According to the fourth aspect of the present invention, since the welding edge is provided at the portion where the blade member is fitted to the shroud so as to be offset from the center thereof, the pressure of ultrasonic welding is applied to the blade member through the main plate or the shroud. In this case, the blade member can maintain an appropriate posture and perform ultrasonic welding. Therefore, the quality of the turbofan can be ensured and the yield can be improved.

  The turbofan of the fifth invention is the turbofan according to any one of the first to third inventions, wherein the welding edge provided at the fitting portion between the shroud and the blade member is provided at the center of the fitting portion. It is characterized by.

  According to the fifth invention, in the case of the blade member in which the positive pressure surface for pushing out the wind of the blade member and the opposite surface thereof have the same shape from the top to the bottom, the same effect as in the fourth invention is exhibited.

  A turbofan of a sixth invention is the turbofan according to any one of the first to third inventions, wherein the blade member is provided with a welding edge at a fitting portion with the main plate and a fitting portion with the shroud. Features.

  According to the sixth aspect, the same effect as in the fourth and fifth aspects is exhibited.

  A turbofan of a seventh invention is the turbofan according to any one of the first to sixth inventions, wherein the air suction hole of the blade member is fitted to the fitting portion on the main plate side or the shroud side into which the blade member is inserted. The welding edge is provided in such a form that the joint is closed.

  According to the seventh invention, the welding edge is provided in such a form that the air suction hole of the blade member is blocked by the fitting portion on the main plate side or the fitting portion on the shroud side into which the blade member is inserted. Therefore, when the blade member is fitted in the fitting portion on the main plate side and the fitting portion on the shroud side and joined by ultrasonic welding, the hollow space inside the blade member and the outside air are not completely communicated with each other. The effect is even more pronounced.

The perspective view which shows the set state at the time of the assembly of the main board, shroud, and blade | wing member of the turbofan of this invention. The perspective view which shows the completed state of the turbo fan of this invention. 1 is an overall schematic view of a main plate of a turbofan of the present invention. The enlarged view of the fitting part of the main plate of FIG. 3 and a blade | wing member. Explanatory drawing of the welding edge of the fitting part of the main plate and blade member of FIG. Explanatory drawing of the state which made the main plate and blade member of FIG. 3 fit. The whole schematic view which looked at the shroud of the turbofan of the present invention from the back side. The enlarged view of the fitting part of the shroud and blade member of FIG. The enlarged view of the fitting part of the shroud and blade member of FIG. Explanatory drawing of the state which made the shroud and blade member of FIG. 7 fit. 1 is an overall schematic view of a blade member of a turbofan of the present invention. Explanatory drawing of the formation process of a blade member. Explanatory drawing of another form of the welding edge of the fitting part in a main plate. The perspective view which shows the completed state of the conventional turbofan.

  The turbofan of the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing the set state of the main plate, shroud and blade member of the turbo fan of the present invention during assembly, FIG. 2 is a perspective view showing the completed state of the turbo fan of the present invention, and FIG. 3 is the turbo of the present invention. 4 is an overall schematic view of the main plate of the fan, FIG. 4 is an enlarged view of a fitting portion between the main plate and the blade member of FIG. 3, and FIG. 5 is an explanatory view of a welding edge of the fitting portion of the main plate and the blade member of FIG. 6 is an explanatory diagram of a state in which the main plate and the blade member of FIG. 3 are fitted, FIG. 7 is an overall schematic view of the shroud of the turbofan of the present invention viewed from the back side, and FIG. 9 is an enlarged view of the fitting portion of FIG. 7, FIG. 9 is an enlarged view of the fitting portion of the shroud and the blade member of FIG. 7, FIG. 10 is an explanatory view of a state in which the shroud and the blade member of FIG. Is an overall schematic view of the blade member of the turbofan of the present invention, and FIG. 12 is a process for forming the blade member of FIG. Of illustration, FIG. 13 is an explanatory view of another form of welding edges of the fitting portion in the main plate, and FIG. 14 is a perspective view showing a completed state of a conventional turbofan.

  In FIG. 2, a turbofan 1 according to the present invention includes a disk-shaped main plate 2, a shroud 3 that forms a fan air guide passage, and a plurality of blade members 4 that connect the main plate 2 and the shroud 3. . Each part is individually injection molded using a thermoplastic resin. The blade member 4 is assembled and joined by fitting into fitting portions provided at a plurality of locations around the main plate 2 and the shroud 3. Bonding is performed by ultrasonic welding. Although the structure of the blade member 4 will be described in detail in <3>, as shown in FIG. The positive pressure surface and the negative pressure surface exhibit a curved surface shape that is necessary for realizing the air blowing characteristics of the turbofan. However, as shown in FIG. 14, the pressure surface that pushes out the wind and the opposite surface (negative pressure surface) may have the same shape (straight) from the top to the bottom.

  Conventionally, when each member is individually molded and assembled and joined, it is difficult to join by ultrasonic welding using a laser welding method. In the laser welding method, it is not necessary to apply pressure to the objects to be joined, and joining can be performed by laser irradiation. However, the device is expensive. Therefore, the turbofan manufactured by the apparatus is expensive. The present invention is intended to solve such problems. The present invention makes it possible to assemble and join individually molded components as shown in FIG. 1 by ultrasonic welding. The inventor made various improvements to the configuration and structure of the constituent members, and reached the present invention. The configuration and structure of each member will be described below.

<1> Structure of Main Plate As shown in FIG. 3, the main plate 2 has a convex hub 22 formed so as to cover the motor at the center thereof, and the shaft of the motor at the center of the hub 22 in the height direction ( And a boss 21 to be inserted and fixed in the vertical direction of FIGS. 1 to 3. Further, as shown in FIG. 3, there are provided as many fitting portions 23 as the number of the blade members 4 in the peripheral portion of the main plate for fitting the blade members when the blade member 4 is assembled and joined.

  The fitting part 23 is configured as shown in FIG. The wall portion 231, the pin portion 232, and the welding edge 233 are formed so as to have a predetermined height and thickness so as to stand on the main plate and circulate. The blade member 4 shown in FIG. 11 is integrally formed by hollow molding or blow molding described later. The bottom part 42 of the blade member 4 is fitted into the fitting part 23. At this time, a hole 46 shown in FIG. 11 is provided in the bottom 42 of the blade member 4, and the pin 232 is inserted into this hole (see FIG. 6). The bottom part 42 of the blade member 4 is fitted and positioned by the wall part 231 and the pin 232. When the bottom part 42 of the blade member 4 is fitted into the fitting part 23, the bottom surface of the bottom part 42 of the blade member comes into contact with the welding edge 233 as shown in FIG. As shown in FIGS. 4 and 5, the welding edges are provided in two rows on the inner side along the wall portion 231 so as to surround the pin 232. The cross section has a substantially triangular shape.

  FIG. 6 shows a state immediately before the main plate 2 and the blade member 4 are joined by ultrasonic welding. By constructing the joint portion 23 as shown in FIGS. 4 and 5, it is possible to join in a stable posture even when receiving pressure applied during ultrasonic welding.

<2> Shroud Structure The shroud 3 will be described with reference to FIG. FIG. 7 is a view of the shroud 3 of FIGS. 1 and 2 as viewed from the back so that the fitting portion 33 can be seen. As shown in FIG. 7, the shroud 3 has a large opening 31 at the center. Further, the peripheral portion 32 is provided with the same number of fitting portions 33 as the blade members, which are fitted to the top portions 43 (see FIG. 11) of the blade members, at positions facing the blade members 4 fitted to the main plate 2. The peripheral portion 32 has a substantially inclined surface in the outer peripheral direction. As shown in FIG. 8, the fitting portion 33 has a step shape according to the shape of the top portion 43 of the blade member, and the top portion 43 of the blade member 4 is fitted and positioned along the wall portion 332. It is configured. The fitting portion 33 is hereinafter referred to as a fitting recess 33 in accordance with the shape of the present embodiment.

  Further, as shown in FIG. 9, a welding edge 333 is provided on the ceiling portion 331 of the fitting recess 33. The welding edge is provided in a row on the ceiling portion of the staircase portion. The welding edge 333 is not on the center of the ceiling portion 331 of the fitting recess 33 but on the pressure surface side of the blade member (the surface side on which the blade member pushes the wind) or the suction surface side (opposite to the pressure surface side). (Surface side) and is biased. In FIG. 9 of the present embodiment, it is biased toward the positive pressure side. The cross section of the welding edge has a substantially triangular shape. When the top portion 43 of the blade member 4 is fitted into the fitting recess, the top portion 43 comes into contact with the welding edge 333 (see FIG. 10).

  When the shape of the blade member 4 is a blade member having the same shape (straight) from the top to the bottom as shown in FIG. It can be. That is, the welding edge 333 provided on the ceiling portion 331 of the fitting recess 33 can be configured to be provided at the center of the fitting recess along the wall portion 332 of the fitting recess 33.

  FIG. 10 shows a state immediately before the shroud 3 and the blade member 4 are joined by ultrasonic welding. By constructing the joint recess 33 as shown in FIGS. 8 and 9, it is possible to join in a stable posture even when subjected to the applied pressure during ultrasonic welding.

<3> Structure of Blade Member The blade member 4 will be described with reference to FIGS. 11 and 12. Since there are a plurality of blade members, it is necessary to make the inside hollow in order to reduce the weight of the turbofan. For this reason, the blade member 4 of the present invention is integrally formed by hollow molding or blow molding. As shown in FIG. 11, the blade member 4 includes a bottom portion 42 that fits into the fitting portion 23 of the main plate 2 and a top portion 43 that fits into the fitting recess 33 of the shroud 3. The pressure surface corresponding to the wing portion of the blade member is 44, and the suction surface is 45. Further, the bottom portion 42 is provided with a hole 46 through which the pin 232 of the fitting portion 23 of the main plate 2 is inserted. This hole 46 is an air suction hole formed at the time of blow molding. Although not shown, the hole 46 may be provided in the top 43 of the blade member 4. In this case, the pin inserted into the hole 46 is provided in the fitting recess 33. The main plate 2 and the shroud 3 are assembled by fitting the bottom portions 42 and the top portions 43 of the plurality of blade members 4 into the fitting portions 23 and the fitting concave portions 33 and joining them by ultrasonic welding.

With reference to FIG. 12, a molding method for integrally molding the blade member 4 by blow molding will be described. A known method can be used for blow molding. The molding is performed by steps 1 to 4 in FIG. 12 as follows.
1) Process 1
The cylindrical resin R melted from the nozzle N is poured into the space between the molds M opened.
2) Step 2
The mold M is closed and the cylindrical resin R is sandwiched.
3) Step 3
The nozzle n is inserted from the mating surface of the closed mold M, air is injected from the nozzle n, and the resin R is molded as a hollow blade member 4 and cooled.
4) Step 4
The mold M is opened and the blade member 4 is taken out.

  By such blow molding, the blade member 4 having a substantially uniform wall thickness and a hollow inner space is obtained.

  As shown in FIG. 11, the blade member 4 of the present invention has an air suction hole 46 formed therein. As shown in FIG. 6, the hole 46 is closed at the bottom of the fitting portion 233 of the main plate 23, and the main plate is joined by ultrasonic welding. Accordingly, it becomes difficult for the inside of the blade member and the outside air to communicate with each other, the rigidity of the blade member is increased, and the structure is difficult to be deformed even when vertical pressure is applied.

  Moreover, the following methods can be adopted as means for improving the rigidity of the blade member after integrally joining the main plate, the shroud, and the blade member. This method will be described with reference to FIG. Fig.13 (a) is a perspective view of the fitting part 23, and FIG.13 (b) is the figure which looked at the fitting part 23 from upper direction.

  In addition to the welding edge 233 in FIG. 4, welding edges 234 and 235 are also provided around the pin 232 as the welding edge provided in the fitting portion 23 with the blade member 4 of the main plate 2. Thereby, when the ultrasonic welding is performed after the pin 232 is inserted into the hole 46 of the blade member, the welding edges 234 and 235 are melted to fill the gap between the hole 46 and the pin 232 of the blade member 4. As a result, the internal space of the blade member and the outside air are not completely communicated, and the rigidity of the blade member is further increased. Accordingly, the rigidity with respect to the applied pressure at the time of molding the turbofan is increased, and a turbofan with higher quality can be obtained. It also leads to improved turbofan performance.

  Further, in the description so far, the welding edge that acts at the time of ultrasonic welding has been provided in the fitting portion of the main plate and the fitting concave portion of the shroud. However, it is not limited to this, For example, it can also be set as the following structures. That is, the welding edge may be provided at the bottom part 42 and the top part 43 of the blade member instead of being provided at the fitting part.

<4> Assembling and joining of the turbofan The main plate 2, the shroud 3 and the plurality of blade members 4 configured as described above are fitted into the fitting portion 23 of the main plate 2 with the bottom portion 42 of the blade member 4 as shown in FIG. 1. In addition, the top 43 of the blade member 4 is fitted into the fitting recess 33 of the shroud 3 to perform temporary assembly. The temporary assembly is hereinafter referred to as “work”. In this state, the bottom portion 42 of the blade member 4 is in contact with the welding edge of the fitting portion 23 of the main plate 2 as shown in FIG. Further, the top 43 of the blade member 4 is in contact with the welding edge of the fitting recess 33 of the shroud 3 as shown in FIG.

  The work temporarily assembled in this way is placed on a jig of an ultrasonic welding machine. The horn of the ultrasonic welding machine contacts and pressurizes a predetermined position of the shroud 3 of the workpiece, the welding edge is melted, and the workpiece is integrated. As shown in FIG. 1, the workpiece can be placed on the jig of the ultrasonic welder by setting the main plate 2 on the jig or by reversing and setting the shroud on the jig. good.

  In this ultrasonic welding process, the configuration of the fitting portion 23 of the main plate 2, the configuration of the fitting recess 33 of the shroud 3, and the configuration in which the blade member 4 is fitted interact with each other, and each member is displaced. Without any problem, it can be ultrasonically welded to the blade member 4. Therefore, it is possible to obtain a turbo fan with stable quality by ultrasonic welding. Moreover, the manufacturing cost is much lower than that of the laser welding method.

DESCRIPTION OF SYMBOLS 1 Turbofan 2 Main plate 21 Boss 22 Hub 23 Fitting part 231 Wall part 232 Pin part 233 Welding edge 234 Welding edge 235 Welding edge 3 Shroud 31 Opening part 32 Peripheral part 33 Fitting recessed part 331 Ceiling part 332 Wall part 333 Welding edge 4 Blade member 41 Main body 42 Bottom portion of blade member 43 Top portion of blade member 44 Positive pressure surface of blade member 45 Negative pressure surface of blade member 46 Hole M Mold N Nozzle n Nozzle R Resin

Claims (6)

A main plate having a boss fixed to the rotation shaft of the motor in the center, a shroud forming a suction air guide wall and a plurality of blade members are separately molded with a thermoplastic resin,
The main plate has a fitting portion with the plurality of blade members,
The shroud has a fitting portion with the plurality of blade members,
The blade member is a blade member formed so as to be integrated by hollow molding or blow molding,
A method of manufacturing a turbofan in which the plurality of blade members are fitted to the plurality of fitting portions of the main plate and the shroud in parallel with a rotation shaft and integrated by ultrasonic welding ,
An air suction hole formed in the blade member for hollow-molding or blow-molding the blade member is provided in a portion that is fitted into the fitting portion of the main plate or the fitting portion of the shroud of the blade member. A method of manufacturing a turbofan. 2. The method for manufacturing a turbofan according to claim 1 , wherein welding edges are provided at a fitting portion between the main plate and the blade member and a fitting portion between the shroud and the blade member . Welded edges provided on the fitting portion between the vane member and the shroud, claim, characterized in that provided to bias the pressure side or suction side of the blade member from the center of the fitting portion 1 or claim 2 A method for producing a turbofan according to claim 1 . It said shroud and welded edges provided on the fitting portion between the blade member, turbofan method according to claim 1 or claim 2, characterized in that provided at the center of the fitting portion. The blade member has fitting portion between the main plate, and turbofan method according to claim 1 or claim 2, characterized in that a welding edge in the fitting portion of the shroud. 2. The welding edge is provided in such a form that the air suction hole of the blade member is closed by the fitting portion on the main plate side or the fitting portion on the shroud side into which the blade member is inserted. A method for producing a turbofan according to claim 5 .

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