JPH0411760B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a plastic cross that is made into divided bodies by dividing a plate into a plurality of pieces radially and integrally molding a plurality of blades on the plate. Regarding the improvement of the flow fan, in particular, the number of blades was increased by reducing the pitch of the blades, which resulted in extremely low noise.

[Prior Art] In a conventional plastic crossflow fan, as shown in FIGS. 10 and 11, notches are provided on the outer periphery of each plate 1, and blades 2 are sequentially fitted into the notches and the notches are heated and caulked. There are some that can be assembled by fixing them with etc. Further, as shown in FIGS. 12 and 13, a large number of blades 7 are integrally provided on the side surface of one plate 8 by injection molding to form a unit, and the right end of the blade is provided at a corresponding position on another plate 8. There are some that are fitted into grooves and connected one after another using ultrasonic welding, etc. Furthermore, as shown in FIGS. 14 and 15, a plurality of blades 5 are integrally injection-molded on the side surfaces of the radially divided plate 4 to form a unit body 3, which is fitted onto the base plate 6, and adhesive is applied to the unit body 3. There are also those that are bonded using ultrasonic waves, etc.

[Problems to be solved by the invention] However, what is shown in FIGS.
Since the blades were fitted to the plate one by one, the number of parts increased, the workability was poor, the number of man-hours was long, and the cost was high.

In addition, the items shown in Figures 12 and 13 are as follows: (a) From the perspective of draft angle during injection molding, if the blade 7 is lengthened, there will be a considerable difference in the thickness at both ends, and in ultrasonic welding, vibrations may cause the tip of the blade to Therefore, in order to obtain sufficient bonding strength, it is necessary to shorten the length of the blade, which ultimately increases the number of units and increases the material cost.

(b) When the number of units increases, the wind distribution becomes uneven, which not only makes it impossible to obtain the uniform wind that is a feature of a cross flow fan, but also reduces the absolute value of the air volume.

(c) When inserting the tips of many blades 7 into the grooves of other plates, the blade tips and plate grooves often shift due to variations in molding conditions and cannot be properly fitted, and it takes a considerable amount of time to fit them together. There were problems such as the need for

Also, what is shown in Figures 14 and 15 is usually shown in Figure 16.
A mold as shown in the figure is used, but in this case, molding cannot be performed unless the pitch A of the blades 5 is widened; for example, a plate with a diameter of 80φ has about 20 blades. In other words, when cutting in the direction of the arrow shown on the right side of the figure, core 1 is removed from the rightmost blade to the leftmost blade.
Since the slope becomes strong with respect to the plane 6, it is impossible to increase the number of blades in order to form a parting line without undercutting. For example, in order to maximize the number of blades, the core tip 16a and the cavity tip 17a have to be made thinner, but this has the problem of shortening the mold life.

Furthermore, this tendency becomes even stronger when a resin containing glass fiber is used to increase the rigidity of the blade. Therefore, the blade pitch A was widened, but this inevitably resulted in a reduction in the overall number of blades, resulting in a major problem such as increased noise and other performance deterioration.

[Means for Solving the Problems] The present invention radially divides the plates arranged on both sides and the middle of a cross flow fan into a plurality of pieces, and integrally inserts a plurality of blades between each plate. In a cross flow fan that is formed by molding into a split blade body and joining a plurality of these split blade bodies, the split plate is divided into two parts at approximately the midpoint height in the radial direction, and an outer plate, a 10 plate, and an inner plate are formed. Blades 11 and 1 are formed between the plurality of adjacent outer plates 10 and between the inner plates 13, respectively.
The outer unit body 9 and the inner unit body 12 are formed by integrally molding the outer unit body 9 and the inner unit body 12, and the inner and outer edges of both unit bodies are fitted and joined to form a split blade body. This is a plastic cross-flow fan characterized by the fact that blades with a fine pitch are obtained by combining multiple blades into a ring shape. As a result, even if the split blade body is integrally molded with a plurality of blades, there is no need to reduce the total number of blades, so a resin cross flow fan with extremely low noise can be obtained.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1 and 2 are diagrams showing an embodiment of the present invention, 15 is a base plate arranged on both sides and the middle part of the cross flow fan, and the inner single body 12
It also functions as a base plate for assembling the outer unit 9 on its outer periphery.

The outer unit body 9 is an outer part formed by dividing a plate into five pieces radially, and is an outer part that is divided into two at approximately the midpoint height in the radial direction of a divided blade body, and connects a plurality of plates 10 and each of these blades. A plurality of blades 11 are integrally molded at a constant pitch as shown in FIG.
It consists of

Note that the inner edge of the outer unit body 9 has a convex portion 9b and a concave portion 9a so as to fit into the concave and convex portions of the inner unit body, which will be described later.
is formed, and the outer edge 9c corresponds to the outer periphery of the finished plate. The reason why the cut surfaces of the two halves are formed into gear-like irregularities is to increase the length of the joint surfaces of both the inner and outer units, thereby increasing the strength of each joint. It is something.

The blade 11 is integrally formed with the convex portion 9b of the plate so that about 1/3 of its width protrudes downward from the inner edge of the plate 10, and this blade 11 is formed integrally with the convex portion 9b of the plate 10 so that about 1/3 of its width protrudes downward from the inner edge of the plate 10. The pitches are arranged approximately twice as many. The total length corresponds to the total length of the crossflow fan.

The inner unit body 12 is an inner part of the aforementioned split blade body, and is composed of a plurality of plates 13 and a plurality of blades 14 integrally formed at a constant pitch so as to connect the plates. A convex portion 12a and a concave portion 12b are formed in the central portion of this outer edge so as to fit into the unevenness of the inner edge of the outer unit body 9, and the inner edge 12c is joined to the outer circumferential portion of the base plate 15 described above. It is.

The blades 14 are formed integrally with the convex portion 12a of the plate 13 so that about 1/3 of the width thereof, excluding the two on the left and right sides, protrudes outward from the outer edge of the plate 13. This pitch is also arranged at approximately twice the pitch of the blade of the product. The total length corresponds to the total length of the crossflow fan.

Then, the outer unit body 9 and the inner unit body 12 are
As shown in the figure, they are combined to form one divided blade body, and this is fixed to the outer periphery of the base plate 15 to constitute one cross flow fan.
That is, FIG. 3 is an enlarged sectional view showing the joined state of each of the unit bodies 9 and 12 described above.
After temporarily assembling the inner unit body 12 on the outer periphery of the inner unit body 12, the outer unit body 9 may be assembled thereon and joined by ultrasonic welding, or the inner unit body 12 and the outer unit body 9 may be assembled in advance. The found split blade body may be joined to the base plate 15.

4 and 5 are partial sectional views of the molds used in the present invention, FIG. 4 being the mold for the outer unit, and FIG. 5 being the mold for the inner unit.

Here, when comparing the blade pitch of the present invention with the conventional blade pitch (Fig. 16), we can see that the conventional blade has a finer pitch from the right side of the blade.
When forming the first and third parting lines, the tip 16a of the core 16 and the cavity 1
7, the third blade from the right shown in FIG. The tip portion 17a does not become thin.

[Function] As shown in FIG. 16, in the conventional product, if the blade pitch A is narrow, the unit body 3 cannot be integrally molded from the viewpoint of die cutting, but the product of the present invention
As shown in Figure 2, the conventional unit body is transformed into an inner unit body 1.
By dividing the blade pitch C of each unit into the blade pitch B of the finished product, as shown in FIG.
Since it can be doubled, it cannot be reduced to half the pitch A of conventional blades, but it can be formed into a considerably finer pitch.

[Other Embodiments] FIGS. 6 and 7 show other embodiments in which the base plate 15 is not used, and the groove 20 formed on the outer periphery of the guide jig 19 made of aluminum, iron, etc. The protruding portion 21a formed on the inner edge of the unit body 21 is fitted, and then the outer unit body 22 is fitted in order so as to straddle the two inner unit bodies, and after they are assembled and joined by ultrasonic welding etc., the guide jig 19 Remove it by pulling it out. This eliminates the need for the base plate 15, reducing weight and materials.

Further, by shifting the positions of adjacent blades as shown in FIG. 8 or by continuously twisting the blades as shown in FIG. 9, the noise of the resin cross flow fan can be further reduced.

[Effect] As described above, since the cross flow fan according to the present invention has a plurality of blades 11, 14 constituting each inner and outer unit arranged every one to several blades,
It is easy to cut out the mold without causing undercuts, and by overlapping the outer unit body 9 and the inner unit body 12, the pitch of the blade can be formed at a considerably finer interval compared to conventional products, so noise can be kept extremely low. The practical effects are extremely large, with improved performance such as an increase in air volume.

[Brief explanation of drawings]

1 and 2 are a side view and a plan view of a cross flow fan showing an embodiment of the present invention. FIG. 3 is a sectional view illustrating a state in which the inner unit body and the outer unit body of the present invention are fitted together. 4 and 5 are partial sectional views of molds for integrally molding the inner unit body and the outer unit body of the present invention, respectively. FIG. 6 and FIG. 7 are a side view and a plan view of a cross flow fan showing another embodiment of the present invention. FIG. 8 and FIG. 9 are plan views showing the shape of other unit bodies of the present invention. FIG. 10 and FIG. 11 are a side view and a plan view of a conventional cross flow fan. FIG. 12 and FIG. 13 are a perspective view and a plan view of another conventional product. FIG. 14 and FIG. 15 are a side view and a plan view of another conventional product. FIG. 16 is a partial sectional view showing a mold for a conventional unit body 3. 5 is a blade, 9 is an outer unit body, 10, 13 are plates, 11, 14 are blades, 12 is an inner unit body, 16 is a core, 16a is a tip of the core, 17
17a is the cavity, and 17a is the tip of the cavity.

Claims (1)

[Claims] 1 Divide the plates placed on both sides and the middle of the crossflow fan into multiple pieces radially,
In a cross flow fan formed by integrally molding a plurality of blades between the respective plates to form a divided blade body and joining these plurality of divided blade bodies, there is a radially intermediate portion of the divided plate. It is divided into two in height to form an outer plate 10 and an inner plate 13, and blades 11 and 14 are arranged in phase with each other every one to several blades between the plurality of adjacent outer plates 10 and between the inner plates 13. The outer unit body 9 and the inner unit body 12 are formed by shifting and integrally molding, the inner and outer edges of both unit bodies are fitted and joined to form a split blade body, and a plurality of these are combined into a ring shape. A plastic cross flow fan characterized by having blades with a fine pitch.