JPH03127643A - Blade of screw conveyer - Google Patents

Abstract

PURPOSE:To prevent the dynamic unbalance by providing backplates and abrasion-proof tips continuously at the housing stage parts confronting the axial direction of screw conveyer. CONSTITUTION:Reinforcing pieces 2 is fixed to the peripheral part of a screw blade main body 1. The reinforcing pieces 2 is made in such a way that a backplate 3 is fixed to the screw blade main body 1 by welding, etc., and then a tip 4 and a cover plate 5 are connected with the backpalte 3. In order to fix the backplate 3 to the screw blade main body 1, the projecting part 3a formed in the bottom end part of the backplate 3 is brought into contact with the side surface of the pushing direction of peripheral part of the screw blade main body 1, and the bottom surface 3b of backplate is brought into contact with the peripheral end surface of screw blade main body 1, and weldings 7a, 7b are carried out. By this method, the tip is easily fixed with good dimensional accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to screw conveyor blades used for conveying powder or slurry materials, particularly materials with a high wear rate, and more particularly: This invention relates to a structure in which wear-resistant chips are fixed to the main body of a screw conveyor around the blades of the screw conveyor. Further, the present invention is particularly suitably applied to a screw conveyor of a centrifugal separator.

[Conventional technology]

In a centrifugal separator, the blades of the screw conveyor, especially the peripheral portions, come into contact with the material to be moved at a high relative speed and are therefore subject to severe wear.

Therefore, it is customary to attach wear-resistant tips to the blades (hereinafter also simply referred to as blades) of the screw conveyor in order to prevent wear on the peripheral portion (tip portion). Various types of reinforcing pieces are known as shown below.

■As shown in FIGS. 11 and 12, insertion holes 1a,
100a, and bolts 101 are inserted into these insertion holes Ia and 100a and fastened with nuts.

■As shown in Japanese Patent Publication No. 51-41707, a back plate to which wear-resistant chips are bonded is welded and fixed to the blade body.

■As shown in Japanese Unexamined Patent Publication No. 51-86870, the tip is fixed in the radial and axial directions with pins via a mating member on the blade body.
As shown in Publication No. 10, a back plate, a substrate, and a chip are locked by dovetail fitting, and these are joined by sintering or casting.

■Utility Model Application No. 83-28139 and Utility Model Application No. 1-1209
As shown in Japanese Patent No. 55, a tip is fixed to the blade body in an engaged state by two stoppers along the circumference having engagement receiving portions.

[Problem to be solved by the invention]

However, each of the above techniques has the following drawbacks.

First of all, in the conventional technique (2) above, it is not only difficult to drill the tip mounting hole at the correct position after attaching the screw blade to the details, but also because the screw blade has a curved surface, there is no play when installing the tip. tends to occur,
Dynamic imbalance is likely to occur due to the high speed rotation of the screw blades. Also, when tightening bolts, if the bolts are tightened too strongly, the chips may crack. Furthermore, if centrifugal force is applied, the supporting force of the bolt holes alone may cause the material to crack due to the pressure of the transported material.

On the other hand, with each of the above-mentioned techniques (1), (2), and (3), chip replacement is difficult. In other words, even tips made of wear-resistant materials will eventually wear out and need to be replaced, but with these technologies,
To replace the chip, it is necessary to weld the board or the holding plate and then re-weld it, which is extremely time-consuming. Furthermore, there is a risk of damaging the quality of the conveyor blades and chips when they are broken off or re-welded.

In addition, with the technology (■) above, the tip can be replaced relatively easily by simply attaching and detaching a small pin by welding, but it is extremely difficult to accurately manufacture a tapered locking groove in the radial direction of the conveyor, and the tip end It takes a lot of effort to maintain the radial dimension accurately.

Therefore, an object of the present invention is to solve the above-mentioned problems so that the tip can be easily attached to the screw blade with good dimensional accuracy without adversely affecting the tip, and in addition, the tip can be easily replaced and the tip can be stabilized. The purpose is to fix it to the blade body in a state where it is held in place.

[Means to solve the problem]

The above problem is solved in a screw conveyor blade provided inside a cylinder, which has a blade root body and a wear-resistant tip fixed to the blade root body; on one side in the radial direction and in the axial direction of the screw conveyor. a blade base body or a back plate fixed to the peripheral portion of the blade base body, in which a housing step portion facing the housing step portion is formed, and an engagement receiving portion that is continuous with the housing step portion and opens in the axial direction is formed in the peripheral portion; A wear-resistant tip that has a main body corresponding to the storage step and an engaging part that is integral with the main body and corresponds to the shape of the engagement receiving part; and a cover plate that is fixed to the housing step, and the main body of the chip is applied to the storage step, and the engaging part of the engaging part moves in the radial direction with respect to the blade body or the back plate without play. This problem can be solved by fixing the tip by clamping it by applying the cover plate to the tip side and fastening the blade body or back plate to the cover plate.

[For production]

In the present invention, when attaching the tip to the screw blade body or to the back plate fixed thereto, the tip itself is not attached by welding or the like, but the engagement between the tip and the screw blade body or the back plate fixed thereto, Furthermore, since the chip is fixed by clamping the chip with bolts, for example, unlike the case of welding the chip itself, there is no adverse effect on the chip itself such as deterioration of quality or cracking due to heat.

Moreover, the tip can be accurately positioned and fixed to the screw blade body or to the back plate fixed thereto by the above-described engagement. Further, since fixation is achieved not only by simple engagement but also by pressing the cover plate against the screw blade body or the back plate with the chip sandwiched therebetween, the fixation is stable.

On the other hand, when replacing the tip due to wear, the tip can be easily replaced by releasing the clamping and engagement of the tip, removing the tip, and re-fixing the tip.

[Specific structure of the invention]

The present invention will be described below with reference to drawings showing specific examples thereof.

1 to 5 show a first specific example of the present invention, and FIGS. 1 and 2 are a sectional view and a front view of the tip of the screw blade, respectively, and the right side of FIG. The direction is the direction in which the material moves by the screw conveyor.

Reference numeral 1 denotes a screw blade base body l, around which a reinforcing piece 2 is fixed. This reinforcing piece 2 is made by first fixing a back plate 3 having a shape to be described later to the screw blade body 1 by welding or the like, and then engaging the chip 4 and the cover plate 5 with the back plate 3 and fastening tools 6 such as bolts. They are integrally connected as shown in the figure.

In order to fix the back plate 3 to the screw blade body 1, a protrusion 3a formed at the bottom end of the back plate 3 is required.
is brought into contact with the side surface of the circumferential portion of the screw blade body 1 in the extrusion direction, and the bottom surface 3b of the back plate is brought into contact with the peripheral end surface of the screw blade root body, and then welding 7 is performed.
This is done by doing steps a and 7b.

FIG. 3 is a perspective view showing the shape of the back plate 3,
At its periphery, a housing step 3e for the chip 4 facing in the radial direction and the extrusion direction is formed, and a dovetail groove 3e continuous to the housing step 3e for engaging and fixing the chip 4, which will be described later. An engagement receiving portion 3c and an insertion hole 3d for passing the fastener 6 therethrough are formed. The reason why the engagement receiving part 3c is made into a dovetail shape is to make it impossible for the back plate 3 and the tip 4 to move relative to each other in the radial direction of the screw blade l due to the rotation of the screw when the tip 4 is engaged. be.

FIG. 4 is a perspective view showing the shape of the wear-resistant tip 4.
It has a main body part 4a having a shape and wall thickness corresponding to the accommodation step part 3e, and a dovetail-shaped engagement part 4b which is integrated with the main body part 4a and corresponds to the shape of the engagement receiving part 3c. .

FIG. 5 shows the cover plate 5, in which tapers 5a are formed at the corners in the extrusion direction of the periphery, and
A screw hole 5b through which the fastener 6 is screwed is formed in the center thereof.

When fixing the chip 4 with the back plate 3, chip 4, and cover plate 5 formed in this way,
First, as described above, the back plate 3 is welded and fixed to the blade body l, and then the chip 4 is brought into contact with its main body part 4a against the accommodation step part 3e, and at the same time, the engaging part 4b is brought into contact with the engaging receiving part 3C.
are fitted and engaged, and then the cover plate 5 is placed over the chip 4 and the back plate 3, and the fastener 6 is inserted from the back plate 3 side through the insertion hole 3d of the back plate 3, and the screw hole of the cover plate 5 is inserted. 5b, pull the cover plate 5 toward the back plate 3,
This is done by clamping and fixing the chip 4 between the back plate 3 and cover plate 5.

Next, a second specific example of the present invention will be explained with reference to FIGS. 6 to 1O. The basic configuration of this second specific example is almost the same as the first specific example, but the shape and/or dimensions of the back plate 30, chip 40, and cover plate 40 that constitute the reinforcing piece 20 in this example are slightly different. The difference is that the fastener 60 is also inserted into the chip 40 and the fastener 60 is further screwed in from the direction of movement of the substance for fastening.

That is, as shown in FIG. 8, saw teeth are formed on the side wall surface of the engagement receiving part 30c of the back plate 30, and an insertion hole 30d is formed at the position of the engagement receiving part 30c. Further, as shown in FIG. 9, the shape of the engaging portion 40b of the chip 40 is such that saw teeth are formed on the side surface thereof corresponding to the engaging receiving portion 30c, and an insertion hole 40c is formed in the engaging portion 40b. It's there. Furthermore, the dimensions of the cover plate 50 are only slightly different. It should be noted that for the same parts as in the first specific example, the same lowercase alphabetic characters are attached to the numerical symbols, and the explanation will be omitted.

In this second specific example as well, the chip 60 is secured basically in the same manner as in the first specific example, except that the fastener 60 is inserted through the insertion hole 40c of the chip 40.

On the other hand, in the first and second embodiments, when the tip 4 or 40 is worn out and needs to be replaced, the fastener 6
Alternatively, after removing the tip 60 and removing the cover plate 5 or 50, the tip 4 or 40 is disengaged, replaced with a new tip, and fixed again.

The shape of the engagement receiving part and the engagement part in the present invention is not limited to the above-mentioned shape example, but the tip is locked to the screw blade body or the cover plate so that it cannot move in the radial direction. It may be of any shape.

Furthermore, the fastener according to the present invention is not limited to screws or bolts that are preferably employed, but clips and the like can also be used. Moreover, it is also possible to fasten with a plurality of fasteners at different positions.

The material of the tip in the present invention must be a wear-resistant material, and tungsten carbide, ceramic, etc. are particularly preferred. Further, as the material of the back plate and the cover plate, an appropriate metal material is usually used.

On the other hand, in each of the above specific examples, the cover plate 3 or 30
The chip 4 or 40 is fixed to the blade base body l through the blade base body 1, but there is a storage step on the back plate on the periphery of the blade base body 1,
The tip 4 or 40 can also be directly fixed to the blade body 1 by forming an engagement receiving portion and an insertion hole for the fastener. However, in this case, after welding and fixing the blade body 1 to the screw conveyor shaft, it is difficult to insert the fastener or position the screw hole and then form it.
Basically it is possible.

〔Effect of the invention〕

As described above, according to the present invention, the chip can be easily attached to the screw blade with good dimensional accuracy without adversely affecting the chip, the chip can be easily replaced, and the chip can be kept in a stable state. It can be fixed to the blade body.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a specific example of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a perspective view showing the back plate thereof, FIG. 4 is a perspective view showing the shape of the chip, and FIG. 5 6 is a sectional view of another specific example of the present invention, FIG. 7 is a side view thereof, FIG. 8 is a perspective view showing the back plate thereof, and FIG. 9 is a perspective view showing the shape of the cover plate. A perspective view showing the shape of the chip, FIG. 10 a perspective view showing the shape of the cover plate, and FIG. 11 a cross-sectional view showing the conventional screw blade.
FIG. 12 is a front view thereof. 1... Screw blade body, 2.20... Reinforcement piece,
3.30...Back plate, 3c, 30c...Engagement receiver, 3e, 30e...Accommodating step part, 4.40...
Chip, 4 a, 40 Mini body, 4 b, 4
0 b--Engagement part, 5.50... Cover plate,
6.60... Fastener. Fig. 1 Fig. Fig. Fig. Fig. Fig. 1

Claims (1)

[Claims] (1) In a screw conveyor provided inside a cylinder, in a screw conveyor blade having a blade root body and a wear-resistant tip fixed to the blade root body; on one side in the radial direction and in the axial direction of the screw conveyor; a blade base body or a back plate fixed to a peripheral portion of the blade base body, on which a facing accommodation step is formed, and an engagement receiving portion that is continuous with the accommodation step and opens in the axial direction is formed on the circumference; A wear-resistant chip that has a main body corresponding to the storage step and an engagement part that is integral with the main body and corresponds to the shape of the engagement receiving part, and a wear-resistant chip that is held against the back plate with this chip sandwiched therebetween. and a cover plate that is fixed, the main body of the chip is applied to the accommodation step, and the engaging part is in the engagement receiving part so that the chip does not move in the radial direction with respect to the blade body or the back plate. The screw conveyor is characterized in that the cover plate is applied to the chip side, and the chips are clamped and fixed by fastening the blade body or the back plate and the cover plate. Feather.