Title of Invention

A MACHINE FOR MANUFACTURING FLASH-LIME/CEMENT BRICKS

Abstract

A machine for manufacturing flash-lime/cement bricks which comprises a metallic chassis (1) consisting of one or more trapezoidal frames (2) and having top and bottom cross bracings (3 & 4), characterized in that the said chassis being provided at its bottom portion with a rigidly fixed horizontal platform (5), a prime mover (6) having electromagnetic clutches (7) and pulleys (8) being fixed to the said platform(5), the said prime mover being connected through V-belts (9) to one or more eccentric shaft (10) housed in housing (11), the said housing(ll) being mounted at the bottom of one or more horizontal plate (12), the said plate(s)(12) resting on a plurality of compression springs (13) mounted on the top of the said cross bracings (3), each of the said plate(s) (12) having fixed at its top at least two channels (14) so as to support a removable pallet (15), the said removable pallet (15) being provided with a plurality of vertically movable moulds (16) held in position by mould support (17) so as to allow a plurality of vertically and horizontally movable punches (18) to impinge on to the said plurality of moulds (16), the said movable punches (18) to impinge on to the said plurality of moulds (16), the said movable punches(18) being swiveling attached to a vertical column(21) through means such as punch holding plate (20), thrust bearings (22), punch support (23), bracket (25) and provided with punch stopper (19) and handle (24), the said column (21) being fixed to the said chassis CD.

Full Text

The present invention relates to a machine for manufacturing fiyash-lime/cement bricks and a process thereof. The machine of the present invention is useful in converting waste like flyash into building bricks on a small scale in urban as well as rural areas, using the process of the present invention. Brick is the cheapest building material presently available in the- country and will continue to be so in the coining decades. Demand of bricks in the country for building construction activities is around 70,000 million bricks whereas the production is 55,000 million bricks per year. The huge shortage (15,000 million bricks) cannot be met by the present production of traditional red clay bricks alone. Therefore, there is a need to develop a parallel material such as flyash-lime bricks that can reduce the heavy burden on traditional red clay bricks Fly ash is an unwanted industrial waste produced as a bye-product of thermal power stations produced when coal is burnt as fuel for generation of electricity. There has been a steady increase in its production due to increased demand of power for industrial, agricultural and other sectors. Presently about 90 million tonnes of flyash is produced in India which with the planned growth of thermal power generation will go to about 120 million tonnes per year in the next decade. It has no apparent use and is causing various problems related to disposal, environmental pollution, health hazard and land use. Sufficient amount of money is spent on its disposal which is dumped on large area of land subsequently making them waste lands. Flyash, has a reasonable order of physico-chemical and mineralogicul compatibility and can be turned into a useful building material such as flyash-Iimc/cemenl bricks. A technology for the production of flyash-sand-lime bricks by high pressure moulding and autoclaving exists in India and abroad. In this technology flyash, sand and hydrated lime in fixed proportions are passed through elevators and double shaft mixers and conveyed to the high pressure press. The bricks are pressed at a pressure of 250-300 kg/cm2. The bricks are removed and loaded on to the trolleys and placed inside curing chamber and are autoclaved at a pressure of 15 kg/cnr. As it is apparent from the description of above mentioned various machines, they are suitable only for large scale production units invariably installed in a centralised factory. Generally the machines associated with the above process consist of the following sub-assemblies. (a) Pressing system consisting of a hydraulic pumping unit to create high pressure for shaping bricks. (b) Brick ejection system incorporating the same hydraulic pumping unit. (c) System for picking and removing the green bricks from the press. M/s. Dorestener, West Germany developed a toggle press for the production of calcium silicate bricks generally known as sand lime bricks. This press consists of a rotary table having 4-12 moulds. The table is rotated in such a manner that when the first pair of moulds is being filled with semi-dry mix, the second is under pressure head while the third pair is under ejection and the fourth pair is under cleaning or brushing operation. Both the pressing and ejection of bricks are done simultaneously by using two different rams which arc kept precisely at their respective places by a hand brake. The maximum pressure exerted by the press is 600 tonnes. By this pressing system, the semi-dry mix in M/s. Atlas-Mak, West Germany have developed a stationary mould type press to produce sand lime bricks. The press consists of a stationary table in which a number of moulds are housed in pairs. At one stage all the moulds are filled with the semi-dry mix one by one and then the pressing operation starts. After the completion of the pressing stroke, the ejection of bricks begins and the automatic take-off device lifts the bricks and stack them on trolleys. The mechanical press later on was modified into a hydraulic model known as Intertechnik. Its drawback is that the press is very expensive because it is a sophisticated machine which makes it out of reach of small entrepreneurs. Another firm M/s. Bruck, Schlosser & Co., GmbH (Germany) have developed various presses which are completely automatic and hydraulically operated. The production rale of these machines vary from 3500 bricks per hour to 5400 bricks per hour. The American "Boyd Press" is a toggle lever press and can also be used for producing sand lime bricks. In this press, pressure is exerted upon both top and bottom faces of the brick in the mould. The press is made in two sizes, each working at a speed of 8 strokes per minute. At this speed the smaller model, fitted with four moulds, has an output of 1920 bricks per hour and exerts a total pressure on six moulds, has an output of 2800 bricks per hour and exerts a total pressure of 600 tonnes. Its drawback is that the press is also very expensive which makes it out of reach of small entrepreneurs. Reference may be made to Indian Patent No. 151381 called "A Rotary Table Press for sand-lime bricks". A rotary table press consists of a horizontal rotary table containing 4 pairs of moulds. The table is rotated in such a manner that while the first pair of moulds is being charged with semi-dry flyash, lime/cement mixture, the next pair of moulds is under the pressure head, while the third pair is under ejection and the fourth pair of moulds is under cleaning operation simultaneously. Both the pressing and ejection of the bricks are achieved at the same time by using two different rams. The table is rotated by a gear mechanism and is stopped automatically after every 90° rotation by a system incorporating an electromagnetic brake, clutch and a shear pin, during this period when the table is stationary the filling of moulds, pressing, ejection and cleaning operations are done simultaneously. After the completion of each cycle, the green bricks are picked up manually and placed on the trolley for the onward transmission to autoclaves. Its drawback is that the rotary table press is very expensive which makes it out of reach of small entrepreneurs. The main object of the present invention is to provide a machine for manufacturing flyash-lime / cement bricks which obviates the drawbacks detailed above. Another object of the present invention is to provide a machine capable of providing vibro-compaction. Still another object of the present invention is to provide a process for manufacturing flyash-lime/cemenl bricks using the machine of the present invention. Yet another object of the present invention is to provide/generate employment in rural sector. In the drawings accompanying this specification, Fig. 1 represents schematic diagram of the machine of the present invention wherein following parts have been shown: 1. Chassis 13. Compression Spring 2. Frame 14. M.S.Channel 3. Top Cross Bracing 4. Bottom Cross Bracing 15. Wooden Pullet 21. Vertical Column 6. Electric Motor 9. V-Belt 22. Thrust Bearing 23. Punch Support 12. Vibrating Plate 24. Handle . Fig. 2 represents front elevation of the machine and shows the following parts : 3. Top Cross Bracing 10. Eccentric Shaft 17. Mould Support 4. Bottom Crossing Bracing 11. Housing 18. Punch 5. Horizontal Platform 12. Vibrating Plate 19. Punch Stopper 6. Electric Motor 13. Compression Spring 20. Punch holding plate 7. Electromagnetic Clutch 14. M.S. Channel 25. Bracket 8. Pulley 9. V-Belt 15. Wooden Pallet 16. Mould 26. Ejection Handle 27. Horizontal Shaft 29. Vertical Shafts Fig. 3 represents side elevation of the machine and shows the following parts : 1. Chassis 12. Vibrating Plate 21. Vertical Column 2. Frame 13. Compression Spring 22. Thrust Bearing 3. Top Cross Bracing 14. M.S. Channel 23. Punch Support 4. Bottom Cross Bracing 15. Wooden Pallet 24. Handle 9. V-Belt 16. Mould 28. Eccentrics Fig. 4 represents the front elevation of prime mover assembly and shows the following parts : 5. Horizontal Platform 7. Electromagnetic Clutch 6. Electric Motor 8. Pulley A very simple machine which is also cost effective has been developed for manufacturing flyash-sand-lime/cement bricks. In this, high pressure moulding technology has been completely replaced by vibro-cornpaction technique. The bricks are shaped by simultaneously vibrating and compacting the bricks from the bottom and top respectively during shaping. Bricks afler shaping are removed manually on pallets. These bricks are kept for natural drying for 24-48 hours depending on the weather conditions and then are steam cured at atmospheric pressure or wet cured for 28 days. Vibro compaction technique has been developed as it requires very little energy during the shaping of bricks. Frequency and amplitude chosen lor vibro compaction mechanism range between 40-60 Hz and 1-2 mm respectively. The water content of the mix is kept ground 20-30% so that during vibration the binder in the slurry form completely envelops the filler material resulting into a very strong bond between the particles and hence optimum strength. The machine is portable and can be easily shifted to different construction sites. The machine has been provided with a novel ejection system wherein all the bricks are ejected easily by applying very little manual effort. Normally for releasing the bricks from the moulds after shaping through vibro-compaction, moulds holding the shaped bricks are removed from the machine and the bricks remolded by applying pressure on top of the mould simultaneously moving the mould box upward. In the machine of the present invention all these operations are in-built. The punches already resting over the bricks during shaping now apply pressure from the top when ejection system operates. This system consist of a horizontal shaft (27) connected to two eccentrics (28) rigidly fixed at the other end. Two vertical shafts (29 are pivoted and fixed to the bottom of the moulds(16). When ejection handle (26) is operated, the vertical shafts (20) push the mould (16 upwards, leaving the bricks at the wooden pallet (15). Accordingly the present invention provides a machine for manufacturing flash-lime/cement bricks which comprises a metallic chassis (1) consisting of one or more trapezoidal frames (2) and having top and bottom cross bracings (3 & 4), characterized in that the said chassis being provided at its bottom portion with a rigidly fixed horizontal platform (5), a prime mover (6) having electromagnetic clutches (7) and pulleys (8) being fixed to the said platform(5), the said prime mover being connected through V-belts (9) to one or more eccentric shaft (10) housed in housing (11), the said housing(ll) being mounted at the bottom of one or more horizontal plate (12), the said plate(s)(12) resting on a plurality of compression springs (13) mounted on the top of the said cross bracings (3), each of the said plate(s) (12) having fixed at its top at least two channels (14) so as to support a removable pallet (15), the said removable pallet (15) being provided with a plurality of vertically movable moulds (16) held in position by mould support (17) so as to allow a plurality of vertically and horizontally movable punches (18) to impinge on to the said plurality of moulds (16), the said movable punches (18) to impinge on to the said plurality of moulds (16), the said movable punches(18) being swiveling attached to a vertical column(21) through means such as punch holding plate (20), thrust bearings (22), punch support (23), bracket (25) and provided with punch stopper (19) and handle (24), the said column (21) being fixed to the said chassis (1). In an embodiment of the present invention, the prime mover is an electric motor capable of providing 3000 rpm to eccentric shaft(10). In another embodiment of the present invention, the eccentric shaft(10) is provided with an eccentricity of 5-10mm. In yet another embodiment of the present invention, the vertically movable moulds are connected top an ejection system consisting of pivoted vertical shafts (29) fixed to the bottom of the moulds, the said vertical shafts being interconnected through horizontal shafts (27), eccentrics (28) to a handle(26). Accordingly the present invention provides a process for manufacturing flyash-lime/cement bricks using the machine of the present invention as described above, which comprises mixing of raw materials such as flyash, sand, lime/cement and water to obtain a homogeneous semi-dry mix, filling the moulds with the mix so obtained, lowering the punches on to the said moulds, subjecting the said mix filled moulds to vibrations of the order of 40-60 Hz and amplitude of the order of l-2mm for 4-6 seconds, raising the punches and ejecting the bricks so formed, followed by drying and then curing. In an embodiment of the present invention, the curing of bricks is done either by steam at atmospheric pressure or wet curing for 28 days. For operating the machine for shaping bricks, the exact quantity of semi-dry mix of flyash, sand and lime/cement is fed to four cavities of steel mould(16) and the punches(18) are swivelled through 180 degrees manually and lowered down to rest on the filled cavities of the mould(16) by operating the handle(24) and the filled moulds are vibrated for 5 seconds by activating the eccentric shaft(10) of the vibrator with the dead load of the punches. After stopping the vibrator, the bricks are ejected by operating a handle(26) and the wooden pallet(15) holding four bricks is taken out manually and placed in the sun for semi-drying, and a fresh wooden pallet(15) is inserted in its place. The machine has an in-built brick ejection system consisting of a horizontal shaft(27) connected to two eccentrics(28) rigidly fixed at the other end. Two vertical shafls(29) are pivoted and fixed to the bottom of the moulds(16). When ejection handle(26) is operated, the vertical shafts(29) push the mould(16) upwards, leaving the bricks at the wooden pallet(15). The mould(16) is brought down to rest on the fresh wooden pallet(15) by operating ejection handle(26). At the time of vibrations, the cavities of the second mould(16) are filled with semi-dry mix and the punches are rotated and brought down to rest on freshly filled cavities. The vibrations are given to the mould(lo) and the whole cycle is repeated. Two sets of moulds(16) have been provided in the machine so that when one of them is being vibrated the other is in the process of filling so that the machine does not remain idle, resulting into optimum production of about 5000 bricks per shift of 8 hours. The machine of the present invention is based upon Vibro-compaction principle as against the pressing principle utilized in hitherto known brick making machines. The novel machine of the present invention converts waste powdery materials into useful building bricks. The inventive step resides in vibro-compaction shaping of bricks. Examples: The following examples are given by way of illustration of the machine and process of the present invention and should not be construed to limit the scope of the present invention. Example I: Flyash : sand : lime-bricks 50 : 40 : 10 The designed machine has been provided with two sets of moulds and one set of four punches which swivel through 180 degrees to rest on both the filled moulds one after the other when required to exert pressure from the top during the vibration period and also to help while ejecting the bricks from moulds. Semi dry mix of flyash sand lime and water is prepared either manually or by feeding the mix to *p+5Xa pan mill. Exact quantity of above mentioned semi dry mix is fed to the moulds and the punches are swivelled manually and lowered down to rest on the filled cavities of the mould. Filled moulds arc subjected to vibrations of the order of 40-60 Hz and amplitude of the order of l-2mm for 4-6 seconds. After vibiation the bricks are ejected through ejection device on to the wooden pallets. Pallet, holding bricks, is removed from the machine and carried to the drying area where they are placed in the sun for 24 to 48 hrs. depending upon the weather conditions. Dried bricks are then loaded into a steam chamber where the bricks are steam cured for 8 hrs. at atmospheric pressure. Bricks are unloaded from the steam chamber on the next day and fresh bricks are loaded in their place and the cycle repeated. In this process the bricks are ready to be used in 24 hrs. after curing. The bricks thus made have the following engineering properties. Wet compressive strength Water Absorption 50-70 kg/cm2 15-18% Example II: Flyash : sand : cement-brick 50 : 40 : 10 The designed machine has been provided with two sets of moulds and one set of four punches which swivel through 180 degrees to rest on both the filled moulds one after the other when required to exert pressure from the top during the vibration period and also to help while ejecting the bricks from moulds. Semi dry mix of flyash sand cement and water is prepared either manually or by feeding the mix to a pan mill. Exact quantity of above mentioned semi dry mix is fed to the moulds and the punches are swivelled manually and lowered down to rest on the filled cavities of the mould. Filled moulds are subjected to vibrations of the order of 40-60 Hz and amplitude of the order of l-2mm for 4-6 seconds. After vibration the bricks are ejected through ejection device on to the wooden pallets. Pallet, holding bricks, is removed from the machine and carried to the drying area where they are placed in the sun for 24 to 48 hrs. depending upon the weather conditions. Dried bricks are then taken to the curing yard and regularly sprinkled with water for 28 days. The bricks are then ready for use. The structural properties of the bricks are : Wet Compressivc Strength Water Absorption 60-80 kg/cm2 13-15% The main advantages of the present inventions : 1. The present invention is cost effective, easy to handle and very much suitable to small entrepreneurs. 2. The machine is cheaper than the existing devices. 3. The machine is capable of producing bricks from various industrial wastes using lime/cement as binder. 4. The machine provides an easy mounting and dismounting of worn out parts. 5. It is simple in construction and requires considerably less attention for repair and maintenance. 6. The machine is so designed that after little training, semi-skilled labour can easily run and maintain it. This increases its suitability for rural areas also, besides urban sectors. We Claim: 1. A machine for manufacturing flash-lime/cement bricks which comprises a metallic chassis (1) consisting of one or more trapezoidal frames (2) and having top and bottom cross bracings (3 & 4), characterized in that the said chassis being provided at its bottom portion with a rigidly fixed horizontal platform (5), a prime mover (6) having electromagnetic clutches (7) and pulleys (8) being fixed to the said platform(5), the said prime mover being connected through V-belts (9) to one or more eccentric shaft (10) housed in housing (11), the said housing(ll) being mounted at the bottom of one or more horizontal plate (12), the said plate(s)(12) resting on a plurality of compression springs (13) mounted on the top of the said cross bracings (3), each of the said plate(s) (12) having fixed at its top at least two channels (14) so as to support a removable pallet (15), the said removable pallet (15) being provided with a plurality of vertically movable moulds (16) held in position by mould support (17) so as to allow a plurality of vertically and horizontally movable punches (18) to impinge on to the said plurality of moulds (16), the said movable punches (18) to impinge on to the said plurality of moulds (16), the said movable punches(18) being swiveling attached to a vertical column(21) through means such as punch holding plate (20), thrust bearings (22), punch support (23) , bracket (25) and provided with punch stopper (19) and handle (24), the said column (21) being fixed to the said chassis (1). 2. A machine as claimed in claim 1 wherein the prime mover is an electric motor for providing 30000 rpm to eccentric shift (10). 3. A machine as claimed in claims 1-2 wherein, the eccentric shaft (10) is provided with an eccentricity of 5 to 10mm. 4. A machine as acclaimed in claims 1-3 wherein, the vertically movable moulds are connected to an ejection system consisting of pivoted vertical shafts (29) fixed to the bottom of the moulds, the said vertical shafts being interconnected through horizontal shaft (27), eccentrics (28) to a handle (26). 5. A process for manufacturing flyash-lime/cement bricks using the machine as claimed in claims 1-4, which comprises mixing of raw materials such as flyash, sand, lime/cement and water to obtain a homogeneous semi-dry mix, filling the moulds with the mix so obtained, lowering the punches on to the said moulds, subjecting the said mix filled moulds to vibrations of the order of 40-60 Hz and amplitude of the order of l-2mm for 4-6 seconds, raising the punches and ejecting the bricks so formed, followed by drying and then curing. 6. A process as claimed in claim 5 wherein the curing of bricks is done either by steam at atmospheric pressure or wt curing for 28 days. 7. A machine for manufacturing flyash-lime/cement bricks substantially as herein described with reference to the examples and drawings accompanying this specifications.

Documents:

366-del-2001-abstract.pdf

366-del-2001-claims.pdf

366-del-2001-correspondence-others.pdf

366-del-2001-correspondence-po.pdf

366-del-2001-description (complete).pdf

366-del-2001-drawings.pdf

366-del-2001-form-1.pdf

366-del-2001-form-18.pdf

366-del-2001-form-2.pdf

366-del-2001-form-3.pdf