[0023] Embodiment 1.
[0024] figure 1 It is a perspective view which shows the structure of the centrifugal blower of Embodiment 1 of this invention. In addition, figure 2 It is a figure which shows the schematic structure of the cross section of the impeller of the centrifugal blower of Embodiment 1 of this invention. Such as figure 1 as well as figure 2 As shown, the impeller 100 of the centrifugal blower of Embodiment 1 is provided with a plurality of ( figure 1 7 in the middle) Blade 2.
[0025] The shield 1 has a bell mouth shape and has an air inlet 1a. In addition, the blade 2 of the present embodiment is a three-dimensional blade having a twisted shape between the shroud 1 and the main plate 3. Therefore, low noise, low power consumption, etc. can be achieved. In addition, a sleeve 4 serving as a rotating shaft is attached to the center of the main plate 3. A drive device (fan motor etc.) is installed on the sleeve 4 to rotate the impeller 100. When rotating, the impeller 100 sucks in gas (for example, air) from the direction of the rotation axis, and discharges the sucked gas in the outer circumferential direction intersecting the rotation axis. Among them, the shield 1, the blade 2 and the main board 3 are made of resin. The guard 1, the blade 2 and the main board 3 are described in detail later.
[0026] image 3 It is a perspective view which shows the structure of the blade of the centrifugal blower of Embodiment 1 of this invention. In addition, Figure 4 It is a cross-sectional view of the structure of the blade of the centrifugal blower according to Embodiment 1 of the present invention viewed from the side (direction substantially perpendicular to the direction of the blade fan). Such as image 3 as well as Figure 4 As shown, in this embodiment, the blade 2 is produced by combining a plurality of components (the main blade 5 and the blade cover 6). When assembling, the main blade 5 and the blade cover 6 can be fixed only by fitting. At this time, for example, a convex portion (not shown) on the surface of the hollow portion 9 of the blade cover 6 is fitted into a bushing 5e (refer to the later-described Image 6 ) To fix. Depending on the situation, it may be further joined and fixed by bonding, welding, or the like. In the present embodiment, in the blade 2, the main blade 5 forms the entire surface of the negative pressure surface 5a and a part of the positive pressure surface 6a. In addition, the blade cover 6 becomes the remaining part of the positive pressure surface 6 a that is not formed by the main blade 5. However, the relationship between the positive pressure surface 6a and the negative pressure surface 5a formed by the main blade 5 and the blade cover 6 is not limited to this. In addition, in the present embodiment, the two parts of the main blade 5 and the blade cover 6 are combined to produce the blade 2, but the number of parts is not limited, and shapes may be combined, and three or more parts may be combined and produced. In addition, by combining the main blade 5 and the blade cover 6, a space that becomes the hollow portion 9 can be formed between the main blade 5 and the blade cover 6. By making the interior of the blade 2 hollow, the weight of the impeller 100 can be reduced, and the cost of materials can be reduced.
[0027] Figure 5 It is a figure which shows the schematic structure of the cross section which looked at the structure of the impeller of the centrifugal blower of Embodiment 1 of this invention from the front side (the direction of the blade fan) of a blade. Such as image 3 as well as Figure 5 As shown, the main blade 5 has a shield-side side surface 5b that is a welding surface that contacts the shield 1 and a main plate-side side surface 5c that is a welding surface that contacts the main plate 3. The blade 2 formed by combining the main blade 5 and the blade cover 6 is arranged between the shield 1 and the main plate 3.
[0028] Among them, since the shroud 1 has a curved shape, it is difficult to perform positioning and the like with the blade 2 (main blade 5). Therefore, on the shroud side surface 5b of the main blade 5 (blade 2), a convex portion 5d whose top surface becomes a welding surface (abutting surface) with the shroud 1 is formed, and a concave portion 1b is formed on the shroud 1, thereby enabling the convex portion 5d is fitted (inlaid) with the recess 1b. Therefore, positioning and welding of the shield 1 and the blade 2 can be performed easily and reliably. On the other hand, the main board 3 has a recess 3a. By providing the main plate-side side surface 5c on the bottom surface portion of the recess 3a, the main plate 3 and the blade 2 can be easily and reliably positioned and welded. Then, by applying laser irradiation, ultrasonic vibration, etc., on the shroud-side side surface 5b of the main blade 5 (blade 2), the contact surface such as the top surface of the convex portion 5d is heated to be welded to the shroud 1. In addition, the part of the side surface 5c on the main board side is heated and welded to the main board 3.
[0029] As described above, the shield 1 and the main plate 3 are joined to the main blade 5 by welding, and the blade 2 is fixed. However, when welding is performed, the shield 1 and the blade 2 are pressurized so that the shield-side side surface 5b and the main plate-side side surface 5c are in close contact. In addition, the main plate 3 and the blade 2 are pressurized. Among them, since the inside of the blade 2 is the hollow portion 9, there is a possibility that, for example, damage caused by pressure may occur. In addition, for example, due to deformation of the blade 2 or the like, there is a possibility that the shroud 1 and the blade 2 cannot be brought into close contact, and the main plate 3 and the blade 2 are brought into close contact. Therefore, for example, it is necessary to perform treatment in advance so as not to damage the blade 2 due to such external pressure.
[0030] Image 6 It is a perspective view showing the structure of the main blade of the centrifugal blower in Embodiment 1 of the present invention. In this embodiment, the main blade 5 is provided with a rib 10 for reinforcement so that the blade 2 can withstand the pressure applied from the outside (especially the pressure during welding). The rib 10 is formed over the entire length connecting the side surface 5b on the shield side and the side surface 5c on the main plate side. Among them, since the blade 2 is a three-dimensional blade, the rib 10 is provided in the hollow portion 9 in this embodiment. By providing this in the hollow portion 9, the shield side side surface 5b and the main plate side side surface 5c can be supported from the inside. In addition, it does not affect the flow of air.
[0031] It is necessary for the rib 10 not to hinder the combination of the main blade 5 and the blade cover 6. Therefore, it is preferable that the height of the rib 10 (the height from the back surface of the negative pressure surface 5a of the main blade 5) is at least along the shape of the portion (inner wall surface) of the blade cover 6 facing the hollow portion 9.
[0032] In addition, as described above, the main blade 5 is made of resin. For example, if ribs 10 are formed on the back surface of the welding surface (contact surface) on the side surface 5b of the shield, etc., the shrinkage after molding increases, and sink marks (dents caused by shrinkage) ) Possibility. Therefore, in this embodiment, the rib 10 is formed so as to be connected to the side wall surface of the convex portion 5d. Therefore, no sink marks are generated on the shield side surface 5b and on the welding surface with the shield 1, so that the adhesion can be maintained.
[0033] As described above, in the centrifugal blower of the first embodiment, since the impeller 100 and the blade 2 are provided with the ribs 10, the deformation of the blade 2 due to external pressure can be suppressed, and damage can be suppressed, and the shield 1 and The adhesion to the motherboard 3 is poor. Therefore, it is possible to maintain the reliability (suppress the decrease in reliability due to deformation). In addition, the shroud 1 and the blade 2, the main plate 3 and the blade 2 can be firmly fixed, and the generation of noise can be suppressed. By providing the rib 10 from the side surface 5b of the shield side to the side surface 5c of the main plate side, it functions effectively against the pressurization at the time of welding. Furthermore, in this embodiment, by forming the rib 10 in the hollow part 9, it can support from the position close to the welding surface (contact surface). In addition, it does not hinder the flow of air during driving. Furthermore, by forming the rib 10 (especially in the height direction) in a shape matching the shape of the blade cover 6, for example, it is possible to prevent the main blade 5 and the blade cover 6 from deforming to the hollow portion 9 side. In addition, since the inside of the blade 2 is formed as the hollow portion 9 (hollow structure), weight reduction can be achieved.
[0034] For example, since the convex portion 5d is formed on the shroud side surface 5b of the main blade 5 and fitted with the concave portion 1b of the shroud 1, positioning of the shroud 1 and the blade 2 is easy, and the welding can be performed firmly Waiting for engagement. At this time, since the rib 10 is formed so as to be connected to the side wall surface of the convex portion 5d, no sink marks are generated on the back side of the welding surface (contact surface), so that the adhesion of the welding surface can be improved.
