JPH0420507Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a striker for an impact crusher that crushes rocks, ores, etc. The present invention relates to a striker for an impact type crusher which is capable of attaching a piece of carbide material to a piece of carbide material and preventing damage to the piece of carbide material, particularly chipping or cracking of the outer peripheral edge.

[Prior art]

A conventional impact crusher is constructed as shown in a schematic cross-sectional view in FIG.

For example, raw ore is fed into the crushing chamber 3 from the raw material supply port 2 installed at the upper side of the impact crusher 1, and the raw ore is fed into the crushing chamber 3 by a blower fixed to the outer periphery of a rotating rotor 5 that rotates around a main shaft 4. Shattered by impact by 6.

The raw stone that is thrown off by the rotating rotor 5 collides with the liner 7a attached to the first repulsion plate 7 provided at the top of the crushing chamber 3 and is crushed.
The rebounding raw stone is crushed by impact by the next hammer 6 which rotates further. Then, the thrown ore is crushed even more finely by the liner 8a attached to the second repulsion plate 8 provided at the upper part of the crushing chamber 3.

In the case of such a conventional impact type crusher, the impactor 6 formed as one piece is generally made of a hard metal material such as high chromium cast iron, high manganese cast steel, or chromium molybdenum cast steel.

However, in this type of impactor 6, since the supplied raw ore to be crushed also contains hard minerals, etc., if the impact is repeated between it and the hard supplied raw ore, as shown in Fig. 5. It will gradually wear out like this.

That is, as shown in FIG.
gradually wears away and deforms into a rounded shape, as shown by the plurality of broken lines in FIG. 5B.

In the conventional impact type crusher, from the viewpoint that it is uneconomical to discard the impactor in this state, the impactor 6 is turned over as shown in Fig. 5C, and the
Use continues until wear progresses as shown by the broken line in Figure D.

[Problem that the invention attempts to solve]

In this way, in conventional impact crushers, the impactor did not have sufficient wear resistance, so when the impactor wears and its tip becomes rounded, it becomes difficult for the object to be crushed to collide head-on. However, the disadvantages were that the crushing capacity decreased and the cost for replacement increased significantly. In addition, the replacement frequency including turning the front and back as described above is, for example, 1.5 to 3 times when crushing rocks for aggregate.
The work of replacing the hammer, which weighs around 100 kg, once every month was extremely demanding.

In order to reduce the wear of such a striker,
It is known that a piece of hard carbide material is attached to the tip of the striker. Such pieces of cemented carbide material are brittle due to their hardness, and if they are shaped to cause stress concentration, they will chip or crack due to impact force, necessitating replacement within a short period of time.

FIG. 6 shows a hammer 6b with a carbide tip 9 brazed to its tip. Such a blower 6
In case b, with continued use, the tip of the carbide tip 9 will wear out as shown by the broken line a, and the wear will eventually reach the joint surface p of the carbide tip 9 to the striking element 6b, as shown in b. move on. At this time, the top q of the striker 6b
is also worn down to the broken line b'. The angle between this worn surface b' and the first top q is approximately 15° (constant).

Afterwards, as the use continues, the wear on the carbide tip 9 side progresses from c to d to e, and the wear on the top side of the striking element 6 increases.
Proceed as c′→d′→e′.

In the progressing process of such wear, a contact point r ₁ where the joint surface p intersects with the wear curved surfaces b, c, d, and e
The tip of the carbide chip 9 facing ~ _r4 , which was initially 90°, becomes an acute angle ( _φ1 ), causing stress concentration in this part.

This end angle φ ₁ becomes even more acute when the joint surface p is tilted as shown by the dashed line p' in order to reduce the amount of material used in the cemented carbide chip, and a large concentrated stress is generated, causing the contact points r ₁ to _{r 4} There was a problem with chipping and cracking in the parts.

Therefore, the object of the present invention is to provide a striker for an impact crusher that has a special structure of carbide chips that are highly wear resistant and do not chip or crack even when worn. .

[Means for solving problems]

The main means adopted by the present invention to achieve the above object are: a rotating rotor that rotates around a main shaft provided inside a casing; The method comprises a plurality of striking elements and a repulsion plate provided at an appropriate distance around the rotating rotor, and causes the raw material splashed by the tip of the rotating striking element to collide with the tip of the striking element and the repulsion plate. In a striker for an impact type crusher that crushes with This is a striker for an impact crusher with chamfered edges.

[Effect]

Since the tip of the striker, which has the highest impact, can be constructed from a piece of carbide material, the cross-sectional shape of the striker hardly changes even after long-term use, and a constant crushing ability can always be maintained. Since the gap between the holes does not become large, the raw material will not fall out from there, and there is no need to adjust the gap between the repulsion plates (conventionally, this was required once every 7 to 10 days). The load on the liner (liner wear) is significantly reduced.

Even if the piece of carbide material at the tip of the striker eventually wears out and the wear reaches the joint surface to the striker (or joint stand), the wear progresses while maintaining the chamfered state, so that it is in contact with the joint surface. No sharp corners that would cause stress concentration are formed at one end of the cemented carbide material. Therefore, it is possible to prevent the cemented carbide material piece from cracking or chipping in this portion.

〔Example〕

Next, embodiments embodying the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, Fig. 1 relates to a striker according to an embodiment of the present invention, Fig. 1a is a side sectional view thereof, Fig. 1b is a front view (right half only), and Fig. 2a and b are respectively. A view corresponding to FIG. 1a showing a modified example of the same striking device, and FIGS. 3 a, b, c, and d are views corresponding to FIG. ).

It should be noted that the following embodiments are merely examples embodying the present invention, and are not intended to limit the technical scope of the present invention.

In FIGS. 1a and 1b, the striker 10 includes a striker main body 11, a plurality of joint stands 14, 14, which are inserted into spigot parts 13, 13, . ...and each joining table 14,1
4, respectively, and each joint base 14, 14, . . . is made up of carbide chips 15, 15, . It is fixed.

The carbide chip 15 is brazed to the joint base 14 using a sandwich solder (a cladding material in which a copper plate is sandwiched between two silver solders).

The carbide chip 15 is an example of a piece of carbide material, and the spigot parts 13, 13, . . . prevent the joining bases 14, 14, . . . from loosening due to impact, and
This is to prevent the bolt 17 from being subjected to a large load due to centrifugal force. An example of the above-mentioned spigot part is shown in FIG. 14, for example.

The carbide chips 15, 15, . . . and the joining tables 14, 14, . Such division may be omitted if necessary, or may be divided only in the direction of the main shaft 4 or only in the radial direction. Furthermore, a plurality of carbide chips 15 may be attached to one joining table 14.

In the examples shown in FIGS. 1 and 2, one cemented carbide chip corresponds to one joining table.

Furthermore, the carbide chips 15, 15, . . . are formed so that the thickness of the carbide chips 15b on the outer peripheral side of the rotating rotor 5 is thicker than the thickness of the carbide chips 15a on the inner peripheral side.

The tips of the carbide tips 15b, 15b, . . . tend to wear out as indicated by broken lines X in the figure.
Therefore, by turning the joining table 14 upside down and using it, it is possible to continue using it until the new tip is worn to the position shown by the broken line Y in the figure.

A chamfer 20 of 15° is formed at the upper end angle of the cemented carbide chip 15 in contact with the surface to be joined to the joining table 14.

The material of the cemented carbide chip 15 includes all so-called cemented carbide alloys. In this way, cemented carbide is made of, for example, tungsten carbide WC as a base material, titanium carbide TiC, tantalum carbide TaC, niobium carbide NbC,
It may contain a mixture of appropriate amounts of vanadium carbide VC, molybdenum carbide Mo ₂ C, titanium nitride TiN, etc., and cobalt C ₀ is often used as a binder.

As a material for the carbide chip 15. For example, K20 (JIS
By selecting B 4104), we were able to achieve a lifespan ratio/cost ratio >1.

In the case of the striker 10 shown in this example, the wear life was more than six times that of the conventional striker made of 27Cr cast iron.
As long as the carbide chip 15 is a brittle material, there is no guarantee that it will never break, so the number of breaks corresponding to the throughput is predicted by calculating the probability of breakage in advance, taking into account the Weibull distribution of rock strength and carbide chip strength. We then carried out proof tests such as load tests to remove any carbide chips that were likely to break.

As a result, inconveniences such as irregular breakage of the chips during use were avoided, and it was also found that the number of carbide chips removed was extremely small, at just a few.

On the other hand, the particle size distribution of the product is at the initial shape of the carbide chip.
It was found that the crushing capacity remained constant as the carbide tips wore out, and there was no decrease in crushing ability.

In the modified example shown in FIG. 2, the thickness distribution is applied to the carbide chips 15b' so as to follow the worn shape, and the amount of carbide chips used is reduced compared to the embodiment shown in FIG. It becomes more economical because it reduces the number of parts, extends the wear life, and requires only one side to be used. In this case as well, it is desirable to form a chamfer 20a.

In Figure b, the back slope of the upper tip 15b'' is made larger than in Figure A to further conform to the worn shape, but in this case, compared to the embodiments in Figures 1 and 2a, As wear progresses, a more acute cross-section is likely to be formed between the worn surface and the joint surface with the joint table on the back, which may lead to chipping. Required.

In addition, in Fig. 2, the position of the upper bolt 17 is shifted toward the center of the rotating rotor as shown in a, or the bolt 17 is inserted at an angle as shown in b. 11' and 11'' are repeatedly used several times, the wear on the top surface of the striking body 11' and 11'' progresses as shown by the broken line, and when it reaches the head of the bolt 17, there is a risk that the bolt 17 may become loose. Therefore, it is desirable to apply such a structure depending on the needs such as the type of raw material.

In a striker having a carbide tip divided into two stages (plurality) in the radial direction of the rotating rotor 5 as described above, by making the carbide tip and the joint base to which it is attached the same shape on the upper and lower sides, the rotating rotor If the tip of the carbide tip on the outer circumference (upper stage) of No. 5 is worn out and becomes unusable, it is possible to extend the life by replacing it with the carbide tip on the inner (lower stage) side. That is, the inner carbide chip serves as a spare. Figures 3 a to d show the striking body 2
One row of carbide chips 20 on the outermost periphery of 1a to 21d
A to 20d are attached. In Fig. 3b, the carbide tip 20b is directly brazed to the striker body 2b, while in Figs. , 20d is the striking element body 2
1a, 21c, and 21d.

In any of the carbide tips shown in FIG.
Chamfers 24a to 24d are formed on the outer peripheral edges of a to 23d. The chamfer 24c in FIG. 3c is inclined inward by 15 degrees with respect to the circumferential direction of the rotating rotor in accordance with the wear shape at the top of the joint base 22c and the striking body 22c.

By providing the chamfers 20, 20a, 20b and 24a to 24d as described above, when the carbide tip 20a wears out, the chamfer 24a also wears out as shown by the broken line in FIG. 3a. However, since the shape of the chamfer 24a that was initially formed remains on the upper end corner of the carbide chip 20a until considerable wear progresses, the upper end corner of the joint surface of the carbide chip 20a does not become an acute angle, and the impact force Since the stress concentration caused by this is alleviated, cracking and chipping of the carbide chip in this area can be minimized.

[Effect of idea]

As described above, the present invention includes a rotating rotor that rotates around a main shaft provided inside a casing, a plurality of strikers fixed to the outer periphery of the rotating rotor, and a plurality of strikers arranged around the rotating rotor. A striker for an impact crusher, which is equipped with a repulsion plate provided at a distance, and crushes the raw material splashed by the tip of the rotating striker by colliding with the tip of the striker and the repulsion plate, A striking device characterized in that a piece of carbide material is joined to the tip of the striker or a joint base that is detachably attached to the tip of the striker, and a chamfer is formed at the outer peripheral end of the bonded portion of the piece of carbide material. Since it is a hammer for a type crusher, the life of the hammer is significantly extended compared to conventional high chromium cast iron, etc., so the cycle of replacing the hammer, which is a heavy labor, can be significantly extended. Ta. Additionally, as the wear of the carbide material pieces progresses, the tips of the sharp corners that are inevitably formed at the upper corners of the carbide material pieces become rounded, making it difficult for cracks and chips to occur in these areas. This made it possible to significantly increase the lifespan per price of expensive cemented carbide material pieces.

[Brief explanation of drawings]

Figure 1 shows a striking device according to an embodiment of the present invention; Figure a is a side sectional view thereof, Figure b is a front view (right half only), and Figures 2 a and b are the same striking elements. Figures 1a, 3a, b, c, and d are views corresponding to Figure 1a showing a modified example of the striker, and Figures 3a, b, c, and d are views corresponding to Figure 1a (however, cross-sections are omitted),
Figure 4 is a side sectional view of a conventional impact crusher, Figure 5 is an explanatory diagram showing the progress of wear on a conventional impactor, and Figure 6 is the progress of wear on the carbide material piece attached to the tip of the impactor. FIG. Explanation of symbols, 10, 10', 10''...Blower,
11, 11', 11'', 21a to 21d...Blower body, 14, 14', 14'', 20a to 20d...
Joint stand, 15a', 15a'', 15b', 15b'', 20
a to 20d...Cemented carbide material piece (carbide chip), 20,
20a, 20b, 24a to 24d... Chamfering.

Claims (1)

[Claims for Utility Model Registration] 1. A rotating rotor that rotates around a main shaft provided inside a casing, a plurality of strikers fixed to the outer periphery of the rotating rotor, and a plurality of striking elements arranged around the rotating rotor. A striker for an impact crusher, which is equipped with a repulsion plate provided at a distance, and crushes the raw material splashed by the tip of the rotating striker by colliding with the tip of the striker and the repulsion plate, An impact impactor characterized in that a piece of carbide material is joined to the tip of the striker or a joint base that is detachably attached to the tip of the striker, and a chamfer is formed at the outer peripheral end of the bonded part of the piece of carbide material. Striker for type crusher. 2. The striker for an impact crusher as set forth in claim 1, wherein the chamfer is inclined at an angle of 15° or more with respect to a tangent to the rotation locus of the outer peripheral end of the joint.