Title of Invention

AN IMPROVED VERTICAL SHAFT IMPACT CRUSHER

Abstract

The present invention relates to an improved arrangement of feeding the material to be crushed in a vertical shaft impactor used for crushing . A path is designed specially to guide the material to enter into the rotor evenly and smoothly without touching the metal parts. A specially designed feed tube and bottom plate leaves the material radially and very smoothly in the rotor. The feed tube and bottom plate is stationary and drops the material in the rotor rotating at high velocity. The bottom plate is provided with a high wear resisting lining on the collar. The material falls on the bottom plate and develops a conical heap over it and slides radially and smoothly in the rotor. This arrangement completely substitutes the distribution cap and also prevents top wear lining of the rotor and thus works more efficiently and reduces the wear cost substantially and thus is more cost efficient.

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) & THE PATENT RULES, 2003 COMPLETE SPECIFICATION [see section 10 and rule 13] TITLE OF THE INVENTION- IMPROVED ARRANGEMENT OF FEEDING IN VERTICAL SHAFT IMP ACTOR. APPLICANTS NAME NATIONALITY ADDRESS - KALANI JUGAL KISHORE KUNJILAL - INDIAN. - H-2, OLD M.I.D.C. SATARA. 415-004 MAHARASHTRA. INDIA The following Specification particularly describes the invention and the manner in which it is to be performed:- Title of the invention - Improved arrangement of feeding in a vertical shaft Impactor. Field of the invention - The invention relates to an improved arrangement of feeding material for crushing in the vertical shaft impactor, more particularly to guide the feed material to enter into the rotor radially through a specially designed feed tube consisting of special rods and bottom plate. Description: BACKGROUND OF THE INVENTION Vertical shaft impactors are used to break rocks , minerals , ores etc., into smaller pieces.Crushing is done by collision of stone by vigorous velocity against each other thus breaking the material into smaller pieces. This crushing is done due to energy imparted to material and collision in crushing chamber. The material to be crushed in a VSI enters from a feeding hopper into the feeding chute and then into the feeding-TUBE and from there into the feed CONE From here it is made to fall on the rotating distribution cap. The distribution cap is a part of the rotor itself and hence it revolves with the rotor. This distribution cap because of its rotation distributes the material to all the ports of the rotor in equal quantity. The material falls upon the distribution cap in perpendicular direction to the plane of the rotor and goes towards the port of the rotor due to centrifugal force. The kinetic energy gained by the particle is proportional to square of the circumferential velocity of the particle .As the distance of the particle from the centre increases its velocity also increases in that proportion. Generally, the diameter of the distribution cap is slightly bigger than the diameter of the feed tube . Obviously the falling particles when touches the rotor plate gains velocity and kinetic energy. This particle touching the distribution cap does not acquire the velocity instantly. As the particle lags behind there is rubbing action between the particle and the distribution cap. This causes the wear of the distribution cap. The more abrasive the material to be crushed , more wear of the distribution cap. For Ex. Materials such as quartzite containing silica upto 95% is very abrasive. When such materials are crushed, the distribution cap gets worn out within few hours and needs to be changed. This increases the wear cost and also requires frequent maintenance, further frequent shutting down of the unit for changing the distribution cap affects the production. Further more as the material falls over the distribution cap at certain velocity it rebounds over the top of the rotor and wears that also increasing the wear cost. Prior art-Several efforts are made in the art to improve the design and construction of VSI crusher to reduce the cost of wear, by changing the material of the wear parts , efforts are also made using different materials and different designs for the distribution cap which is a very important part and is subject to heavy wear. U.S. Pat. No. 5,954,282. discloses an impeller assembly including wear resistant rods press fit into bores formed in the VSI crusher assembly. And incorporate a flat central feed disc(distribution cap) for receiving material from a hopper. The hard material used to construct the rods has much greater wear resistance than the ferrous material used to construct the body of the impeller. U.S. Patent no. 7,028,936 provides for Hard material insert bars embedded and bonded together in a preselected pattern within a center feed disc body (distribution cap) cast from a metal such as air hardened steel. Thus reducing wear on the surface of the center feed disc. These and all the other known wear resistant solutions provided in the art have there own Shortcomings. U.S. patent no. 5,954,282 suffers from the lacuna that the wear resistant rods fixed on the ferrous body are more durable then ferrous body. So when the ferrous body is weakened due to impact of the material, the rods are knocked off. U.S. Patent no. 7,028,936 though has helped in increasing the break down period. But it does not reduce the wear cost to that level as the cost of the distribution cap is increased substantially because of the costly wear resistant material used . Thus the cost of the wear is a matter of significant concern in VSI crushers as no efficient solution has yet been devised to overcome the wear problem and that too in a cost efficient manner. The present invention purports to provide for an effective solution for the problems faced in the art. Object of the invention- Hence , it is the foremost objective to modify the way of feeding the material into the rotor so that the wear is reduced thus minimising the wear cost. It is another objective to devise an open ended feed tube to disburse the material to be crushed evenly and radially in the rotor to avoid rebounding. Another objective is to replace the high wear distribution cap and save on the costs of its wear. It is also the objective to avoid the rebounding of the material to prevent wear at the top of the rotor. It is also the further objective to prevent frequent breakdowns and increase in the production.. Another objective is to decrease the repairs and maintenance cost due to wear. Its further objective is to reduce in the energy consumption. As the material is made to leave into the rotor very swiftly and hence no energy consumption in changing the direction . Its additional objective is to increase the efficiency. The most important objective is to achieve all the above in a most cost efficient manner. SUMMARY OF THE INVENTION The material to be crushed enters into a VSI through the feeding hopper the feeding chute the feeding cone and from there into the feed tube. The material then falls on the distribution cap. The distribution cap is a part of the rotor of the VSI. It revolves along with the rotor and distributes the material to be crushed in the rotor evenly. The material falling on the distribution cap due to its velocity and high impact causes a substantial wear of the distribution cap. In the present invention the feed material from the feeding hopper till the rotor is guided in such a way that it falls at the centre of the rotor and distributed evenly. Further the feed tube is designed in such a way that the material falls on a stationary dish type plate which is the subject of the present invention and which is attached to the feed tube. The material falling on the plate forms a conical heap and the next material gets diverted and enters the rotor very smoothly parallel to the plane of the rotor without rebounding . The bottom plate is provided with a collar which is lined with high wear resistant material The plate is suspended at the bottom end of the feed tube by means of three or four vertical steel rods. The function of the rods is to serve as suspenders for the bottom plate . Hence they can be aligned in various possible combinations and the plate can either be suspended by a single rod or multiple rods depending upon the capacity and design of the crusher. This rods provide as side openings for the feed tube. They being subject to continuous flow of feed material are more prone to wear hence they are protected by high wear resistant wear material bushes . The arrangement of the bottom plate and the rods is designed in such a way that a conical stone lining is developed automatically at the bottom end of the feed tube above the bottom plate which protects the bottom plate from wear. This arrangement enables the feed material to fall in the plane of the rotor at a reduced velocity. As soon as the material touches the bottom plate of the rotor, it starts moving away from the centre due to centrifugal force. Because the velocity of the feed material is in radial direction. it saves the energy and the wear. This bottom plate being atttached to the fixed feed tube does not rotate as does a distribution cap hence no wear. Moreover, there is no impact of the material on the rotating hard surface , hence no rebounding of the material over the topside of the rotor. This further prevents the wear of the top side of the rotor and thus increases the efficiency and reduces the wear cost and as no energy is required for absorbing the energy of the material and throwing the material out, there is also a saving on the energy. The perusal of the following brief and detailed description of the invention with the help of drawings and the claims will make the invention more clear and those skilled in the art will know that it purports to achieve the objectives set. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross- sectional view of the VSI crusher showing its various embodiements along with the prior art distribution cap. FIG. 2 is a cross- sectional view of the VSI crusher showing its various embodiements along with the invented arrangement without the distribution cap. FIG. 3 is a cross sectional view showing the invented path of the material in the VSI crusher from the feeding hopper via the feed tube into the rotor. FIG.4 is a detailed view of the feed tube along with the invented bottom plate. FIG. 5 is a tranverse view of the rotor showing the flow of the material in the rotor. DETAILED DESCRIPTION OF THE DRAWINGS : Fig. No. 2 depicts the VSI crusher (1) which comprises of a feeding hopper (15) It opens into a feed chute (2) through a diverting plate (16 A). This in turn opens into the feed tube (3) which is fitted with the help of a sleeve (4) in taper ring (5). The sleeve(4) fitting of the feed tube(3) is devised in such a way that the feed tube (3)is co-centric with the rotor(11). Further the fitment arrangements of the feed tube(3) are made adjustable to raise and lower its height with ease. The feed tube(3) ends with a bottom plate (8) in such a way that the plate lies suspended over the locking plate (9) of the rotor (11) without touching it. The locking plate (9) in turn locks the rotor (11) which is mounted over the shaft and housing assembly (12). The rotor (11) is rotated at high speed by the driving pulley (13). Fig. 4 depicts that a bottom plate (8) is fitted to the feed tube (3) with the help of long steel rods (6) fastened with nuts (6)(A) at the bottom end of the feed tube(3).The rods (6) are covered with high wear resistant bushes (7).This arrangement of the bottom plate (8) and the rods (6) makes the feed tube (3) having side openings which aids in dispersing the material evenly on all the sides of the rotor(11). The bottom plate (8) is stationary as it is fitted to the feed tube(3) which is also fixed. The bottom plate (8) is made up of mild steel and is provided with a collar which is lined with high wear resistant material(8A) Fig 5 shows that the wear sectors (10) are fitted to the bottom plate of the rotor (11). These are also locked by the locking plate (9) . These wear sectors (10) protect the rotor body (11) from wearing as the feed material passes over it. The wear sectors (10) are fitted at ports (not shown)near the tip plate (22) which are the outlet opening for the crushed material. The wear sectors (10) may range from 3 to 5 as per the capacity of the crusher. The material comes out from the rotor (11) sliding over wear sector (10) through the port.(not shown). Fig.3 shows the path of the feed material (21).The material (21) falls in the feeding hopper (15) and passes over its stone lining and drops over the centrally located diverting plate (16A) which has a stone lining (16) developed. Material fall along the circumference of plate (16A) and falls in feed cone (2) over lining (17). Again the material enters circumferentially in the feed tube (3). At the bottom of the feed tube (3) a stone lining (18) is developed which again diverts the material to fall centrally on the bottom plate (8) over which a conical shaped lining (19) of a heap of stones is developed The material falls on the bottom plate(8) due to gravity at low velocity. Hence no impact and so there is literally no wear of the bottom plate.(8) Next the material slides over it and enters on the wear sector (10) smoothly and takes the path (20) over the tip plate (22) as shown in fig. 5. The tip plates (22) are arranged in such a manner that an autogenous stone lining (23) is developed which protects the rotor(11) from wear. The wear sectors (10) which are fitted to the rotor (11) revolves at very high speed and so the material slides over the wear sectors (10) and are thrown out of the rotor (11) by centrifugal force. Further the smooth radial flow of the material from the feed tube(3) into the rotor(11) compromises with the movement of the material in the rotor(11 ).The stone linings (16), (17), (18).and (19) prevents the metal parts to come in with the feed material(21) and also guides the feed material (21) to fall at the centre of the rotor(11) thus being effective in reducing the wear. The material then comes out of the rotor port(not shown) and is imparted with kinetic energy . This material with high energy strikes over pigeon ring (14) and develops autogenous tough stone lining. Material strikes over this lining and gets broken due to rock on rock crushing principle. Thus in the present invention the feed material(21) is being guided in VSI in such a way that the material enters evenly in the rotor.(11) The material falls smoothly over the bottom plate(8) with low velocity hence there is no rebound of the material over the top of the rotor(11) which happens when there is a rotating distribution cap(26) as shown in Fig.1. This dispenses the need of the top liner (25)of the rotor(11) and it also saves on energy. Any changes and modifications in the essence of the invention shall be construed to fall within the ambit of the invention and shall be given the widest interpretation to fall within the ambit of the invention. Abstract: The present invention relates to an improved arrangement of feeding the material to be crushed in a vertical shaft impactor used for crushing . A path is designed specially to guide the material to enter into the rotor evenly and smoothly without touching the metal parts.A specially designed feed tube and bottom plate leaves the material radially and very smoothly in the rotor. The feed tube and bottom plate is stationary and drops the material in the rotor rotating ay at high velocity. The bottom plate is provided with a high wear resisting lining on the collar. The material falls on the bottom plate and develops a conical heap over it and slides radially and smoothly in the rotor. This arrangement completely substitutes the distribution cap and also prevents top wear lining of the rotor and thus works more efficiently and reduces the wear cost substantially and thus is more cost efficient. I Claim: 1. An arrangement for feeding the material in VSI for crushing which comprises of a specially designed path to guide the material evenly at the rotor without coming in contact with the metal parts of the VSI which includes a specially designed feed tube , wherein the feed tube comprises of rods and a bottom plate. 2. A fixed plate as in claim (1) being provided at the bottom of feed tube which distributes the material smoothly and evenly at the rotor. 3. The fixed bottom plate as in claim (1) and (2) being attached to the feed tube by means of rods covered with high wear resistant material bushes. 4. The bottom plate as in claim (1), (2) and (3) being kept suspended co-centric with the rotor over the locking plate without touching it. 5. The sleeve fitting of the feed tube as in claim (1) being designed so that the feed tube is co-centric with the rotor. 6. The fitment arrangement of the feed tube as in claim(1) being designed so that the feed tube can be raised or lowered with ease. 7. The specially designed feeding arrangement as in claim (1) comprising of feeding hopper, centrally located plate, lining of the feed cone, feed tube and the conical stone lining of the bottom plate. 8. The feeding hopper stone lining as in claim (7) which directs the material over the centrally located plate. 9. The centrally located stone lining plate as in claim (7) and (8) being developed to let the materials fall along its circumference and over the feed cone lining and into the feed tube. 10. The feed tube lining as in (7), (8) and (9 )diverting the material over the conical stone lining of the bottom plate and then radially into the rotor. 11. The stone linings as in claim(1), (7), (8), (9) and (10) being designed to minimise contact of the material with the metal of the VSI.

Documents:

1368-MUM-2007-ABSTRACT(7-2-2011).pdf

1368-mum-2007-abstract.pdf

1368-MUM-2007-CLAIMS(AMENDED)-(29-10-2012).pdf

1368-MUM-2007-CLAIMS(AMENDED)-(7-2-2011).pdf

1368-MUM-2007-CLAIMS(MARKED COPY)-(29-10-2012).pdf

1368-MUM-2007-CLAIMS(MARKED COPY)-(7-2-2011).pdf

1368-mum-2007-claims.pdf

1368-MUM-2007-CORRESPONDENCE(22-6-2012).pdf

1368-mum-2007-correspondence-received.pdf

1368-mum-2007-description (complete).pdf

1368-MUM-2007-DRAWING(29-10-2012).pdf

1368-mum-2007-drawings.pdf

1368-MUM-2007-FORM 1(7-2-2011).pdf

1368-MUM-2007-FORM 2(TITLE PAGE)-(7-2-2011).pdf

1368-MUM-2007-FORM 26(29-10-2012).pdf

1368-MUM-2007-FORM 26(7-2-2011).pdf

1368-mum-2007-form-1.pdf

1368-mum-2007-form-18.pdf

1368-mum-2007-form-2.pdf

1368-mum-2007-form-26.pdf

1368-MUM-2007-REPLY TO EXAMINATION REPORT(29-10-2012).pdf

1368-MUM-2007-REPLY TO EXAMINATION REPORT(7-2-2011).pdf

1368-MUM-2007-REPLY TO HEARING(29-10-2012).pdf