JPS5937135B2 - Manufacturing method of curved rotary impeller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a curved rotary impeller whose blades have a curved surface.

A curved rotary impeller I having a curved surface 1 as shown in FIG.
have traditionally been manufactured by a precision casting method such as a lost wax method or a die casting method using a split mold.

However, no matter which casting method is used, the curved surface 1
Since it is necessary to form a cavity that matches the shape of the blade portion R, it is necessary to manufacture molds and casting equipment with complicated shapes and structures, and the manufacturing costs of the molds, casting equipment, etc. are reduced. As a result, these casting methods have the disadvantage that the production cost of the curved rotary impeller I increases significantly.

Another problem was that impellers that would interfere with the shape of the blades when the split mold was moved in the radial direction after casting using the split mold could not be cast using this method. The present invention has been made in view of these problems, and its purpose is to first produce straight lines arranged radially without using expensive molds or casting equipment having complicated curved cavities. The present invention provides a method for manufacturing a curved rotary impeller by casting a rotary impeller having shaped blades and then bending the straight blades.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

FIG. 2 shows a rotary impeller I' in which the blade portion R' obtained by the tool casting process of the present invention has a plurality of flat straight blades extending radially with respect to the shaft portion 2.

In order to manufacture this rotary impeller machine, conventionally known methods such as the above-mentioned stow wax method or die casting method can be used, but when emphasis is placed on productivity, it is preferable to use the die casting method. A split mold device used when casting the tool rotary impeller I' shown in FIG. 2 by this die casting method has, for example, the structure shown in FIG. 3A. That is, the mold 3 is capable of forming a cavity corresponding to the shape of the shaft portion 2 and the blade portion R' of the impeller I', that is, the number of blades on which the carved surface 3a' corresponding to the tool shape is engraved. It has a mold 3 made up of a set of the same number of split molds 3a. These split molds 3a are arranged in a space formed by the upper and lower mold frames 4 and 5 and the side frames 6. J These divided molds 3a are each connected to a drive cylinder 8 via a holder 7, so that they can move forward and backward in the radial direction. At this position, the mold is kept closed, and the gear via of the impeller I' can be formed.

Inside this cavity is a plunger mechanism (detailed illustration is omitted, but there is a cylinder P with a built-in plunger shown in the center of the lower formwork 5 with a two-dot chain line at the bottom, etc.)
After press-fitting the molten metal and hardening it, the drive cylinder 8 is operated in the direction of arrow M to open each split mold 3a, and a straight-blade rotary impeller as shown in FIG. 2 is cast. It is something.

The mold 3a has its engraved surface 3a as shown in FIG.
′ is not a curved surface, the mold 3a can be easily manufactured by conventional machining such as milling and grinding, and the manufacturing man-hours and This method has the advantage that costs can be significantly reduced and repairs due to wear and tear on the mold are easy.

In other words, to machine a mold with a curved surface, it is necessary to use an expensive precision machine tool such as a copying machine that uses a model or an NC machine, which in turn increases the manufacturing cost of the mold. The disadvantage was that it led to an increase in

Next, a curved blade processing step of bending the straight blade rotary impeller (see FIG. 2) obtained in the above process will be described.

FIGS. 4 and 5 show an embodiment of a curved wing bending device used in this curved wing processing step.

In each figure, similarly to what is shown in FIG. This is a rectangular screw-get part formed at the base (this screw-get part will eventually be cut and will not become a product). Reference numeral 10 denotes a base having a receiving surface 11 at the center which is counterbore-processed to fit into the screw-get portion B, and 12 represents a rotary impeller provided on the base 10.
The clamping member 14 is a means for fixing the clamp member 14, and is comprised of a plurality of grooves 13, a clamp member 14 that fits into the grooves 13, and has an engaging portion 14a at one end that engages with the screw-get portion B, and a bolt 15.

Reference numeral 16 denotes a rotary member for bending each straight blade Y, and the rotary member 16 has a groove 19 carved in the axial direction inside the rotary member 16 and having the same number of curved surfaces 18 as the number of blades. .

Reference numeral 20 denotes a receiving portion for supporting the rotation of the rotating member 16, and in this embodiment, it is constituted by a projecting piece erected on each of the clamping members 14.

Reference numeral 22 denotes a rotating means for the rotating member 16, which includes a pinion 23 carved in a part of the upper outer peripheral wall surface of the rotating member 16, a rack 24 that meshes with the pinion 23, and a drive cylinder for moving the rack 24. 25.

26 is a bearing of the rack 24.

In addition, the pinion 23, rack 24 and drive cylinder 2
It is also possible to use a worm, a worm gear, and a motor for rotationally driving the worm in place of 5, and use these as the means for rotating the rotating member 16. Next, based on the above configuration, the operation in this curved blade processing step will be explained.

First, as shown in Figs. 4 and 5, a straight-blade rotary impeller ``
The screwget part B of is placed on the receiving surface 11 of the base plate 10.

Next, use the bolt 15 to tighten the engaging portion 14 of the clamp member 14.
By pressing the rotary impeller ``a'' against the screwget part B, the rotary impeller ``is firmly fixed on the base 10. Thereafter, the rotating member 16 is inserted from above the rotary impeller 1' while engaging the pinion 23 provided on its outer periphery with the rack 24, and placed inside each receiving portion 20 of each clamp member 14. In this way, the assembly of the rotary impeller 1'' and the rotating member 16 is completed.Then, move the drive cylinder 25 to the arrow Y.
When the rack 24 is operated in the Y direction, the rack 24 moves in the Y direction, thereby causing the rotating member 1 rotatably supported on the receiving portion 20 to move in the Y direction.
6 will rotate in the direction of arrow X.

Then, each curved surface 18 of the rotary member 16 comes into contact with each of the straight blades y of the rotary impeller, and bends them.

Then, when the rotating member 16 is further rotated and the straight blade y is bent to a curvature that is almost the same as the curvature of the curved surface 18 as shown by the chain line in FIG. (in the opposite direction to Y) to return the rotating member 16 to its original position 1.
1C: Return. In this way, the straight-blade rotary impeller 1'' shown in FIG. 2 is bent into a curved-blade rotary impeller 1 by bending each blade with a constant curvature as shown in FIG. 1. After this, The screwget part is removed by cutting near the boundary between the screwget part B and the shaft part 2, for example at the two-dot chain line S in FIG. The straight blade casting process consists of two processes: a straight blade casting process in which the car is cast, and a curved blade processing process in which the straight blades of the rotary impeller obtained in this straight blade casting process are subjected to a certain bending process. Instead of using an expensive mold with a curved surface, it is sufficient to use a mold that can cast straight blades, which is easy to manufacture, so the casting process can be made much cheaper than in the past.
Furthermore, the curved blades can be formed easily and quickly by mechanical bending.

[Brief explanation of drawings]

Figure 1 is a perspective view of a curved rotary impeller including a screwget part, Figure 2 is a perspective view of a straight blade rotary impeller including a screwget part, and Figure 3A is a straight blade rotary impeller shown in Figure 2. A side sectional view of the split mold device for casting impellers, Figure 3.
A sectional view taken along the mouth line, FIGS. 4 and 5 are a plan view and a longitudinal sectional view of the curved blade bending apparatus used in the present invention. ``...Straight-blade rotary impeller, F'...straight blade, B...visget part, I...curved-blade rotary impeller, 12. ...Means for fixing the rotary impeller 1', 16...Rotating member, 18...
Curved surface, 20... Receiving portion of rotating member 16, 22.
...Rotating means for the rotating member 16.

Claims (1)

[Claims] 1. A straight blade casting process in which a rotary impeller having straight blades arranged radially is cast, and a curved blade in which the straight blades of the rotary impeller obtained in this straight blade casting process are bent in a predetermined direction. A method for manufacturing a curved blade rotary impeller, comprising a processing step.