JP2864892B2 - Method and apparatus for manufacturing impeller of vortex blower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an impeller of a vortex blower used as a pneumatic power source for assembling a pneumatic device such as a pneumatic conveying device for powdery and granular materials, an adsorbing device for paper and the like, and aeration, etc. The present invention relates to an apparatus, and more particularly to a method and an apparatus for manufacturing an impeller of a swirl blower suitable for use in an impeller of a swirl blower having a three-dimensionally shaped blade.

[0002]

2. Description of the Related Art In a conventional vortex blower, the blades of an impeller are generally formed radially and flatly.
This vortex blower has a feature of being small and capable of obtaining a high wind pressure, and various proposals and studies have hitherto been made to utilize this feature. In particular, various proposals have been made for the shape and structure of the impeller in response to increasing demands for a small and lightweight vortex blower, high discharge pressure, and low noise. As one of the proposals, it has been proposed to form the blade of the impeller into a three-dimensional shape having good aerodynamic characteristics.

However, in putting a vortex blower having a three-dimensional blade into practical use, a method of manufacturing the impeller becomes a major problem. That is, the impeller of a conventional vortex blower having a two-dimensional blade has a relatively simple shape and can be manufactured mainly by a casting method such as die casting. However, in such a conventional method, an undercut portion occurs due to the three-dimensional shape of the blade of the impeller, and it becomes impossible to remove the mold after casting.

As a solution to such a problem, for example, Japanese Patent Laid-Open Publication No. Sho 51-57011 discloses that when such an impeller is manufactured by casting, the impeller is divided into two parts in the direction of the rotation axis, and each is divided into two parts. It is disclosed that after casting, these are combined to complete an impeller. It proposes a method that makes the core of the mold unnecessary.

Another method is disclosed in Japanese Patent Application Laid-Open No. 2-9 / 1990.
No. 22, Japanese Patent Application Laid-Open No. H11-122, discloses a method of manufacturing an impeller having a three-dimensional blade by separately molding a shroud and a blade constituting an impeller, and plastically fastening the shroud and the blade in a separate process. It has been disclosed.

[0006]

Among the above-mentioned prior arts, the method of dividing the impeller into two in the direction of the rotation axis does not take into consideration a more advanced three-dimensional shaping of the blade of the impeller. There is a problem that it is difficult to cope with an impeller having a more complicated shape. That is,
When manufacturing an impeller having such a complicated shape, since the blade has a three-dimensional shape, the product cannot be removed from the casting mold, and cannot be dealt with by general die casting or mold casting. Will occur.

On the other hand, a method in which a shroud and a blade are separately formed and plastically fastened to each other in a separate process can manufacture an advanced three-dimensional impeller, but on the other hand, a plurality of blades are assembled to the shroud. In addition, in order to plastically fasten this, it takes an extremely large number of man-hours, and it is inevitable that a small gap is generated in the contact surface between the shroud and the blade, causing a pressure loss.

The present invention has been made in view of the above points, and an object of the present invention is to integrate an impeller of a vortex blower having an impeller having blades of a considerably complicated three-dimensional shape by a mold. SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for manufacturing an impeller of a vortex blower which can be manufactured at a low speed.

Another object of the present invention is to integrally manufacture an impeller of a vortex blower having an impeller having blades of a complicated three-dimensional shape without the need for a mold core. An object of the present invention is to provide a method and an apparatus for manufacturing an impeller for a swirl blower.

Still another object of the present invention is to provide a method and an apparatus for manufacturing an vortex blower in which an impeller having a blade having a three-dimensional shape with better aerodynamic characteristics can be integrally formed. It is in.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is characterized in that a shroud having an annular groove having a substantially semicircular cross section centered on a rotation shaft, and the annular shape of the shroud is provided. When integrally molding a vortex blower impeller having a plurality of blades that are arranged across the groove and that are concavely curved with respect to the rotation direction by a casting mold, the mold is disposed between adjacent blades. A first mold forming at least a rotational front surface of the blade;
The blade is divided into a second die that forms the rear surface in the rotation direction of the blade, and the impeller is formed by casting. First, the second die is pulled out in the axial direction of the impeller. Is rotated in the rotation direction of the impeller, and then the first die is removed in the axial direction of the impeller.

In a preferred apparatus configuration for realizing the above-mentioned method, a first mold forming a front surface in the rotational direction of the blade and a second mold forming a rear surface in the rotational direction of the blade are provided separately. Second mold moving means for pulling out the second mold in the axial direction of the impeller, and rotating the first mold in the rotational direction of the impeller, and moving the first mold in the axial direction of the impeller. And a first mold driving means.

[0013]

According to the above configuration, the second mold can be pulled out in the axial direction of the impeller without any hindrance by the blade due to the characteristic shape of the blade of the impeller. Then, by removing the second mold, the second mold is placed on the back of the first mold.
The gap is secured by an amount corresponding to the mold of (1). The first type is
It has penetrated the undercut caused by the shape of the blade. Therefore, the mold cannot be removed in the axial direction as it is. Therefore, the first die is rotated and moved in the rotation direction of the impeller by utilizing the gap generated by removing the second die. Thereby, the first mold can be removed from the undercut portion and can be pulled out in the axial direction.

This makes it possible to manufacture the impeller integrally by molding, and to manufacture an impeller having a complicated three-dimensional blade without any special core or the like. it can.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 2 is a cross-sectional view of an eddy blower provided with an impeller manufactured according to the present invention, wherein 1 is an impeller, 2 is a casing forming an annular flow path 8, and 4 is an electric motor for rotatingly driving the impeller 1. It is. The impeller 1 and the casing 2 face each other,
The impeller 1 is rotatably attached to the casing 2. The electric motor 4 is fixed to the base member 7a and the casing 2. One end of the annular flow passage 8 communicates with the suction-side passage 6a, and the other end communicates with the discharge-side passage located at the back of the suction-side passage 6a in the drawing. The suction side passage 6a and the discharge side passage are provided in the silencer 7 which also serves as the base member 7a. The annular flow path 8 is formed in a circular shape around the rotation center of the impeller 1, that is, the rotation shaft 3 of the electric motor 4, and when cut along a plane passing through the axis of the rotation shaft 3, its cross-sectional shape has a semicircular shape. It is formed to form. A small gap is maintained between the suction port 6 and the discharge port communicating with each other in the annular flow path 8 so that the plurality of blades 5 forming the impeller 1 can pass between the suction port and the discharge port. Partition walls are formed so as not to be separated.

FIG. 3 is a partially cutaway perspective view showing the impeller 1. The impeller 1 is composed of a wheel 9 and a shroud 11, which are fixed to the rotating shaft 3 of the electric motor 4 and rotate integrally therewith. You. An annular groove 10 is formed in the shroud 11. The annular groove 10 is formed in an annular shape around the rotation center of the impeller 1, that is, the rotation center axis 3C of the electric motor 4, and is open on the side parallel to the rotation center axis 3C, and has a semicircular shape as shown in the figure. Are formed as grooves. In the annular groove 10, a number of blades 5 are provided integrally with the shroud 11 in a direction crossing the groove 10.

In the case of this embodiment, the blade 5 is inclined with respect to the rotation direction F of the impeller 1, and preferably has a curved surface which is concavely curved with respect to the rotation direction F. As a result, when viewed from the side of the annular groove 7 in the axial direction of the impeller 1, a portion hidden by the blade 5, that is, an undercut portion 12 is formed on the side in the rotation direction F of the blade 5, and the presence of the undercut portion 12 Accordingly, the mold cannot be removed during the integral molding with the mold.

The annular flow path 8 provided in the casing 2 and the annular groove 10 provided in the impeller 1 are arranged so that their opening sides face each other. By rotating the impeller 1, a vortex is generated between the annular groove 10 and the annular flow path 8 by the action of the blade 5, and the gas sucked from the suction port 6 is gradually pressurized, and the pressure is increased. The changed gas is discharged from the discharge port.

When the blades 5 are arranged in the annular grooves 10 provided in the shroud 11, these blades 5
As shown in FIG. 5, the case is arranged so as to extend in the radial direction from the rotation axis center line 3 </ b> C, and as shown in FIG. 5, the case is arranged at a predetermined angle from the radial direction to the rotational direction F. As shown in FIG. 6, there are cases where the blades 8 are arranged so as to form a curved line.

The sectional shape of the central portion of the blade 5 cut along a concentric circle centered on the rotation axis center line 3C is also shown in FIG.
FIG. 7A illustrates a case where the blade is curved in the rotation direction F of the impeller 1, and FIG. 7B illustrates a case where the blade is linearly inclined in the rotation direction F of the impeller 1. As shown in FIG. 7 (c), there are various shapes such as a combination of a portion 5a parallel to the rotation axis center line 3C and a continuous inclined portion 5b.

Next, a method of manufacturing an impeller provided with such a three-dimensional blade will be described. FIG. 1 shows a configuration of a split double-acting movable type for manufacturing an impeller 1 according to an embodiment of the present invention, and a basic operation. 20a, 2
Reference numeral 0b denotes a first type and a second type disposed between the adjacent blades 5 on the opening side of the impeller 1. The first mold 20a forms the front surface 5f in the rotation direction F of the blade 5, and the second mold 20a
b forms the rear surface 5r of the blade 5 in the rotation direction F. 21
Is a back surface type forming a back surface opposite to the opening side of the impeller 1. Hereinafter, for convenience of explanation, the first mold 20a is referred to as a fixed nest, the second mold 20b is referred to as a movable nest, and the back mold 21 is referred to as a fixed mold.

As shown in FIG. 1A, the fixed nest 20
a and the movable nest 20b and the fixed mold 21 are clamped,
As a result, a cavity 22 for forming the shroud 11 and the blade 5 is formed. Molten metal in this cavity,
Alternatively, the shroud 11 of the impeller 1 and the blade 5 are integrally cast and molded by injecting molten plastic. Of course, the wheel 9 is also molded at the same time. In this state, since at least the fixed insert 20a has entered the undercut portion 12 formed by the blade 5, it cannot be removed in the axial direction of the impeller 1.

Therefore, in this embodiment, FIG.
After the molten metal or plastic in the cavity 22 is solidified, the movable insert 20b is first slid in the axial direction of the impeller 1, here in the direction C, and pulled out. Thereby, a gap A is secured between the back surface of the fixed nest 20a and the adjacent blade 5. So, next,
The stationary nest 20a is slid in the direction of rotation of the impeller 1, in this figure two directions, that is, as shown in FIG. 1 (c), the stationary nest 20a and the movable nest 20b are bidirectionally concentric with the rotation axis center line 3C. Rotate and move. Thereby, the fixed nest 20a can be removed from the undercut portion 12. Then, as shown in FIG. 1D, if the fixed nest 20a is pulled out in the direction of E and the mold is opened, an impeller having a three-dimensional blade can be manufactured without using a core. Become.

FIGS. 4, 5 and 6 show that the number of blades 5 is one.
Although an example of five blades is shown, the number of blades 5 is determined by the diameter of the blades 5 circumscribing and, as shown in FIG. Various settings can be made according to the value of the undercut portion 12 at which the product does not come off, that is, the depth H1 of the blade when cross-sectioned concentrically with the rotation axis center line 3C, and the distance H2 between the front surface 5f and the rear surface 5r of the adjacent blade 5. There is no limit to the number.

FIG. 8 is a plan view showing the movement of the split double-acting type. FIG. 8 (a) shows that the movable nest 20b and the fixed nest 20a are also clamped, and the cavity 22 has molten metal, plastic, or the like. Is injected to form an impeller. FIG. 8 (b) shows that only the movable insert 20b opens the mold after the molten metal, plastic, or the like has solidified, so that between the fixed insert 20a and the rear surface 5r of the blade,
This shows a state in which a gap A in which the fixed insert 20a rotates is formed. FIG. 8C shows a state where the fixed nest 20a is rotated, and FIG. 8D shows a movable nest 20b and the fixed nest 2a.
This shows a state in which all the movable dies including 0a have been opened, and there is no obstacle in taking out the impeller 1. Therefore, even an impeller having a three-dimensional blade can be manufactured without using a core.

FIG. 9 shows an embodiment of a mold apparatus which realizes the above, and is partially cut away. In this figure,
The left half of the figure shows a state where the mold is clamped during molding, and the right half of the figure shows a state where the movable insert 20b slides. Reference numeral 30 denotes a division line where the movable mold 31 and the fixed mold 32 are in contact with each other. Reference numeral 22 denotes a cavity formed by the movable mold 31, the movable insert 20b, the fixed insert 20a, and the fixed mold 32. Molten metal or plastic is injected into the cavity 22 from the sprue 34 to form the impeller 1. As described in FIG. 1, in order to take out the product from the mold, first, the slide cylinder 35 as the second mold driving means for sliding the movable insert 20b is provided. The fixed nest 20a, the movable nest 20b, and the movable mold 3
A rotary cylinder 36 is provided as first mold driving means for rotating the first mold 1. Reference numeral 37 denotes an extrusion pin for taking out a product.

As described above, in the embodiment, when the impeller 1 is molded by the method shown in FIG. 1 using the mold apparatus shown in FIG. 9, the number of blades 5 becomes H2 ≧ H in FIG.
One constraint occurs. In order to eliminate this restriction, the movable nest 20b as shown in FIG.
If the rotation in the two directions shown in FIG. 1C and FIG. 1D and the opening in the direction E are simultaneously performed, that is, H2 ≦ H1 is possible if the mold is removed obliquely with respect to the rotation axis center line 3C. Can be increased. In order to simultaneously perform the rotation in the two directions and the mold opening in the direction E, two-axis simultaneous control by a servo motor may be performed. It may be driven to move.

In the above-described embodiment, the case where the mold between the adjacent blades 5 is divided into two is described. However, the number of the molds is not limited, and the moving direction and the removing direction of the mold are various. Applicable. FIG. 10 shows an embodiment in which the mold between the adjacent blades 5 is divided into three. That is, according to this embodiment, the molds arranged between the adjacent blades 5 include the mold 20a forming the front surface 5f of the blade 5 and the mold 2 forming the rear surface 5r of the blade 5.
0b and the third mold 2 between these molds 20a and 20b.
0c is arranged. The mold 20a and the mold 20c are joined obliquely at the slope 20p. In FIG. 10, only one location between the adjacent blades 5 is shown, but the other components have the same configuration. The back type is omitted because it is the same as above. FIG. 11 is a plan view of FIG.

FIG. 12 shows the operation of the embodiment shown in FIG. 10 and 11 show a state where the mold is clamped during molding. In this state, molten metal or plastic in a molten state is injected into the cavity 22,
After these are solidified, first, the mold 20b is pulled out in the axial direction as shown in FIG. Next, as shown in FIG. 12B, the mold 20c and the mold 20b are slid in an oblique direction along the angle θ1 of the slope 20p, and are pulled out in the axial direction. continue,
As shown in FIG. 12 (c), the molds 20a, 20b, 20c
Is rotated in the rotation direction F of the impeller 1 by a predetermined frequency X. Then, as shown in FIG.
0b and 20c are pulled obliquely at an angle θ2. In this way, there is no obstacle in taking out the impeller 1. Therefore, even an impeller having a three-dimensional blade can be manufactured without using a core. In addition, according to this embodiment, the interval between the blades 5 can be made extremely small, and the impeller 1 having more blades 5 can be manufactured.

FIG. 13 shows an embodiment of a manufacturing method in which the mold between the adjacent blades 5 is divided into two and the interval between the blades 5 can be made smaller. That is, according to this embodiment, the mold arranged between the adjacent blades 5 is replaced with the mold 20a that forms the front surface 5f of the blade 5.
And a mold 20b that forms the rear surface 5r of the blade 5. At this time, a slope having an angle θ1 is formed above the mold 20b. In FIG. 13, only one location between the adjacent blades 5 is shown, but the other components have the same configuration. The back type is omitted because it is the same as above. FIG. 14 is a plan view of FIG.

FIG. 15 shows the operation of the embodiment shown in FIG. 13 and 14 show a state where the mold is clamped during molding. In this state, molten metal or plastic in a molten state is injected into the cavity 22,
After these are solidified, first, the mold 20b is removed in the axial direction as shown in FIG. Next, as shown in FIG. 15 (b), the mold 20 a and the mold 20 b are rotated by a predetermined frequency X in the rotation direction F of the impeller 1. Subsequently, as shown in FIG. 15C, the molds 20a and 20b are raised by a predetermined dimension Y.
Next, as shown in FIG.
Incline along the inclined surface 20p provided in the above. And then,
As shown in FIG. 15E, the molds 20a and 20b are
2 Pull out diagonally.

In this manner, the impeller 1 is provided in the same manner as described above.
There is no obstacle in taking out. Therefore, 3
Even an impeller having a three-dimensional blade can be manufactured without using a core. Not only that, according to this embodiment, the blade 5
Can be made extremely small, and the blade 5
Can be manufactured.

As described above, according to the embodiment, in manufacturing the impeller of the vortex blower having the shroud 11 and the plurality of blades 5, the movable mold is divided into at least two parts in order to form one blade. These split movable dies not only open and close the mold, but also are a split double-acting movable type that rotates about a rotation axis, and are integrally formed with an impeller having three-dimensionally shaped blades. Such excellent effects can be easily obtained.

That is, low-pressure casting using a core is generally used for an impeller provided with a three-dimensional blade. In this case, since there is a problem such as hot run, the thickness of the wall is reduced. This is difficult to reduce, and as a result, it is also difficult to reduce the second moment of inertia of the impeller, and there is a problem that the drive motor cannot be downsized. However, according to the embodiment, the three-dimensional impeller can be formed by die-casting or injection molding by the split double-acting movable mold. It is possible to make the electric motor necessary for driving sufficiently small.

In general, when manufacturing an impeller having three-dimensional blades, a plurality of cores obtained by firing sand in a microwave oven are used to form the blades. +, -0.2 to 0.5 mm, which is not so good, so that as the number of blades increases, the thickness of the blade varies, resulting in an impeller with poor balance and poor surface roughness of the blade surface. Therefore, in terms of performance, pressure loss is large, balance correction processing is required, and the core becomes waste sand, which increases the cost of industrial waste treatment and the like. However, in the case where the split double-acting movable type impeller of the embodiment is provided with a three-dimensionally shaped blade, since the core is not used, the blade surface is smooth and has no pressure loss. Waste treatment becomes unnecessary, and a high-performance vortex blower can be reliably supplied at low cost.

[0037]

As is apparent from the above description, according to the present invention, an impeller of a vortex blower having an impeller having blades of a complicated three-dimensional shape is integrated with a mold without using a core. Thus, a method and an apparatus for manufacturing an impeller of a vortex blower that can be manufactured at a high speed can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of the present invention, and is a view showing a molding step of an impeller.

FIG. 2 is a partial sectional view showing one embodiment of a vortex blower provided with an impeller according to the present invention.

FIG. 3 is a perspective view showing one embodiment of an impeller according to the present invention, and is partially cut away.

FIG. 4 is a plan view showing another embodiment of the impeller according to the present invention.

FIG. 5 is a plan view showing still another embodiment of the impeller according to the present invention.

FIG. 6 is a plan view showing still another embodiment of the impeller according to the present invention.

FIG. 7 is a circumferential sectional view of an impeller showing an embodiment of the present invention.

FIG. 8 is a plan view showing a forming step using a split double-acting movable mold according to the present invention.

FIG. 9 is a view showing a partially cut mold apparatus used in the present invention.

FIG. 10 is a sectional view showing another embodiment of the present invention.

FIG. 11 is a plan view of FIG. 10;

FIG. 12 is a process diagram showing a molding process of FIG. 10;

FIG. 13 is a sectional view showing still another embodiment of the present invention.

FIG. 14 is a plan view of FIG.

FIG. 15 is a process chart showing a molding process of FIG. 13;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Impeller, 2 ... Casing, 3 ... Rotary shaft, 4 ... Electric motor, 5 ... Blade, 8 ... Annular flow path, 10 ... Annular groove, 11
... shroud, 12 ... undercut part, 20a ... first
, 20b ... second mold, 21 ... back mold, 22 ... cavity, 31 ... movable mold, 32 ... fixed mold, 30 ... division line, 34 ... gate, 35 ... slide cylinder, 36 ... rotary cylinder.

Continuation of the front page (72) Inventor Fumiaki Ishida 7-1-1 Higashi Narashino, Narashino City, Chiba Prefecture Inside the Narashino Plant, Hitachi, Ltd. (56) References JP-A-57-17815 (JP, A) JP-A-4- 253541 (JP, A) JP-A-3-189398 (JP, A) JP-A-51-57011 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04D 29 / 18-29 / 38

Claims (6)

(57) [Claims] 1. A shroud having an annular groove having a substantially semicircular cross-section centered on a rotation axis, and a plurality of blades disposed across the annular groove of the shroud and curved concavely with respect to the rotation direction. When integrally molding the impeller of the vortex blower provided with a casting mold, a mold disposed between the adjacent blades is a first mold that forms at least a front surface in the rotation direction of the blade, and the blade After the impeller is formed by casting, the second mold is first drawn out in the axial direction of the impeller, and then the first mold is formed. Rotatively moving in the direction of rotation of the impeller, and then removing the first mold in the axial direction of the impeller. 2. When the second mold is pulled out in the axial direction of the impeller,
The method for manufacturing an impeller of an eddy blower according to claim 1, wherein the second mold is pulled out obliquely along the axial direction of the impeller. 3. When the first mold is pulled out in the axial direction of the impeller,
2. The method for manufacturing an impeller of an eddy blower according to claim 1, wherein the first mold is extracted obliquely along the axial direction of the impeller. 4. A shroud having an annular groove having a substantially semicircular cross-section centered on a rotation axis, and a plurality of blades arranged across the annular groove of the shroud and curved concavely in the rotational direction. A casting mold for integrally molding an impeller of a vortex blower comprising: a first mold that forms at least a front surface in the rotation direction of the blade; A second mold moving means for separating the second mold in the axial direction of the impeller; and a second mold moving means for pulling out the second mold in the axial direction of the impeller. And a first mold driving means for rotating the first mold in the axial direction of the impeller. 5. The impeller manufacturing apparatus for an eddy blower according to claim 4, wherein the second mold driving means drives the second mold to move obliquely along the axial direction of the impeller. 6. The apparatus for manufacturing an impeller of an eddy blower according to claim 4, wherein the first mold driving means drives the first mold in an oblique direction along the axial direction of the impeller.