JPS6058126B2 - How to make conveyor screws - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method for welding, assembling, and manufacturing conveyor screws with variable screw diameters.

Conveyor screws are normally manufactured by welding and attaching blades to the screw shaft, but since screw blades are generally made from sheet metal, the shape of the blade can be precisely determined, especially when there are multiple pitches or the outer diameter changes. It is difficult to assemble a high-precision screw because it is difficult to extract the screw, and it also deforms when welding it to the shaft.

In order to solve this problem, attempts have been made to manufacture screws by dividing the blade, successively piecing them together, and welding them to the shaft. There are some inconveniences that you have to prepare for.

In addition, the working surface of the blade, especially its peripheral edge, is constantly rubbed by conveyed objects and easily wears out, so wear-resistant materials are welded over or pasted. Highly wear-resistant materials may be prone to cracking or peeling, or when multi-layered, may become annealed due to heat build-up from repeated welding, reducing wear resistance, or In addition, attaching the wear-resistant material to the blade surface by brazing etc. requires considerable effort, and even if it wears out locally, it is difficult to replace just that part, so if you use it as is, the screw There are various problems such as shortening the lifespan of the machine. The purpose of this invention is to provide a method for manufacturing a screw that solves the above-mentioned problems, and is a method for manufacturing a conveyor screw with a variable screw diameter by welding and assembling the screw. The blade pieces are assembled by fixing a wear-resistant piece to the periphery of the working surface of the annular or annular spiral blade segment, and the blade pieces are sequentially welded and attached to mounting seats provided in a spiral shape on the shaft surface. The present invention relates to a method for manufacturing a conveyor screw.

The present invention will now be described in detail with reference to the accompanying drawings.

A shaft 1 whose diameter changes from one side to the other has a height H.
A blade 2 having a constant diameter is helically attached to form a screw 3. The blade 2 is a blade divided piece 5a
A plurality of multistage fan-shaped annular blade pieces 5 having a wear-resistant piece 4 fixed to the peripheral edge thereof are successively attached to a mounting seat 11 spirally provided on the surface of the shaft 1.

A multi-stage fan-shaped ring is a shape in which several so-called fan-shaped rings are overlapped and connected on a plane, and FIGS. 2 and 3 show two-stage fan-shaped ring blade pieces 5 arranged adjacently. . The more types of blade pieces there are, the better the adhesion between adjacent blade pieces caused by differences in diameter, but in order to achieve mass production effects, it is necessary to reduce the number of types.

When the types of blade pieces are limited, a gap is created between adjacent blade pieces due to the difference in diameter between the large diameter side and the small diameter side of the screw, but when the planar shape of the blade piece is made into a multi-stage fan shape, this gap is can be made smaller. That is, in FIGS. 2 and 3, R1 is based on the radius on the small diameter side, and R2 is based on the radius on the large diameter side. Therefore, small diameter fan angle a1 = 3600/Rll (where n1 is the number of blade pieces on the small diameter side), large diameter fan angle A2 = 360 side/Rl2 (however, j is the number of blade pieces on the large diameter side)
There is a relationship of n1/N2=R1/R2. By doing this, a gap is created in the upper half on the small diameter side and in the lower half on the large diameter side. However, this size can be reduced to half a sector. Furthermore, by providing multiple stages, the gap value can be reduced accordingly. In addition, the fan angle a on the small diameter side
1 is determined by taking into consideration the forging accuracy or casting accuracy, the amount of gap between adjacent blade pieces, the lead angle, etc. For example, for a screw with an outer diameter of about 600wn, the fan angle a1 is about 20
It is practical to set it to 400. In addition, the curvature radii RO and Ri of the arcuate outer and inner circumferences of the blade piece are set to the average value of the large diameter side and small diameter side of each type, so that the height H from the screw seat due to the difference in diameter can be made uniform. I can do it.

The shape of the wear-resistant piece 4 to be attached to the multistage fan-shaped annular divided piece 5a may be manufactured in accordance with the shape of the peripheral portion of several types of divided pieces to be attached.

In other words, the radial length of the wear-resistant piece 4 may be determined by the length of the heavily worn part of the blade, and the size should be within a range that does not impair the adhesion with the blade segment having a lead angle. The size is large (usually about 5 x 6 Crf1 square), the planar shape is a multi-stage fan-shaped annular shape similar to the blade segment, and the amount of gap between adjacent wear-resistant pieces is minimized. The width Wa is set to be the same as the width W of the divided piece, or to a fraction of an integer. A blade piece is formed in advance by attaching a wear-resistant piece to a divided piece, and brazing using a high-frequency heating device is convenient for attachment. Instead of manufacturing blade segments by casting or forging, cuts 9 are made in the radial direction in a material 8 which is made by cutting a plate material into an annular shape, and the split pieces 1 are made by opening left and right at the cuts to give a twisted shape.
0, and when attaching the wear-resistant piece 4 to this to make a blade piece, it is easy to manufacture a blade piece with a - pitch or a half pitch, so the shape and dimensions of the blade piece will differ for each pitch, and there will be more or less types. The surface condition is smooth, and since the number of blade pieces is small and they form part of a spiral shape, it is easy to attach and detach from the shaft, and it is also advantageous in terms of strength because it promotes integration. If the plate thickness is set to 6 to 7 wn or more, deformation during installation can be prevented.

The shape of the wear-resistant piece to be attached to such an annular blade piece is based on the same idea as the fan-shaped annular blade piece described above, for example, the shape is based on the outer circumference of each blade piece or every few pitches on the large diameter side and small diameter side of the blade. If the fan-shaped ring or the multi-stage fan-shaped ring is used, only one type of wear-resistant piece is required for each blade piece or for every several pitches. To facilitate precision installation of each blade piece onto the shaft, the shaft 1
A blade mounting seat 11 is provided in advance.

The mounting seat may be integrally cast when the shaft is made by casting, or it may be attached by welding afterwards. The shape of the seat may be, for example, a single-flange type as shown in FIG. 7 or a fitted type as shown in FIG. 8. To attach the blade piece to the shaft,
In the case of a fan-shaped annular shape, use a jig (not shown) to line up the inner end of the blade piece with the seat, first fix the blade piece to the shaft by fillet welding on one side, then weld the fillet weld on the opposite side. Adjacent blade pieces are joined together by welding the back side butt parts. As the blade pieces are installed one after another, the shape of the inner diameter side and the outer shape of the shaft will become different, and a gap will be created between the two, but this is convenient because the mounting seat also serves as a backing. be. If adjacent blade pieces are overlapped on the sides of the blade pieces in a so-called parallel manner, even if a gap occurs as mentioned above, the overlapping partner will act as a backing metal, making welding easier. be.

As explained above, when using the method of the present invention, the screw blade is divided into divided pieces, and a wear-resistant piece is fixed to this in advance to form a unit blade piece.
This is welded to the mounting seat provided in a spiral shape on the outer surface of the screw shaft, making the installation and assembly work easy.
Moreover, the process can be carried out quickly, and a highly accurate screw can be obtained.

Also, since it is easy to replace the blade pieces for each unit, you can replace only the parts that are severely worn, and unlike replacing only the wear-resistant pieces, you can replace the entire blade piece of the unit, so only the wear-resistant pieces can be replaced. There is no deformation of the blade as would occur when replacing it. By making the blade pieces into a multistage fan-shaped ring shape, it is possible to reduce the number of types of blade pieces required to assemble one screw, and it is also convenient because the types used can be the same for different models. It is.

Also, if the blade piece is made into an annular shape, for example, with a pitch or a half pitch, the number of types will increase somewhat, but it will be easier to attach it to the shaft and assemble it, and it will also be possible to use a screw with a blade with a smoother curved surface. Obtainable.

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[Brief explanation of the drawing]

] Fig. 21 is a partially exploded side view showing an example of a screw suitable for carrying out the method of the present invention, and Figs. 2 and 3 show the shape and arrangement of the fan-shaped annular blade piece (blade segment). FIG. 4 is an explanatory plan view of the annular blade piece, FIGS. 5 and 6 are side views, and FIGS. 7 and 8 are cross-sections of main parts showing an example of the mounting seat. It is a diagram. 1...shaft, 2...blade, 3...
...Screw, 4...Wear-resistant piece, 5
a...Blade division piece, 5...Blade piece, 6...Gap, 7...Gap, 8
...Circular material, 9...Cut, 10.
...Divided piece, 11, 12...Mounting seat.

Claims (1)

[Claims] 1. In a method of welding and assembling a screw for a conveyor with a variable screw diameter, a wear-resistant piece is provided on the periphery of the working surface of a multi-stage sector-shaped or annular-spiral segment into which a screw blade is divided. A method of manufacturing a conveyor screw by assembling blade pieces by fixing them together, and sequentially welding and attaching the blade pieces to a mounting seat provided in a spiral shape on the shaft surface. 2. A method of manufacturing a conveyor screw according to claim 1, wherein the wear-resistant piece has a multistage fan-shaped ring shape.