International Journal of Engineering and Technology Volue No., February, 01 Developent of a Meat Slicing Machine Using Locally Sourced Materials Odior, A. O. Departent of Production Engineering, University of Benin, Nigeria ABSTRACT In an attept to facilitate the processing of eat which is a daily nutritional food requireent of an, a eat slicing achine has been developed. The achine consists of a cutting blade, a eat feeder, a eat tray, a eat clap, the crank echanis and a control unit. The achine was designed to enhance the hygienic slicing of eat for both doestic and coercial consuption and it can accoodate fro one to six cutting blades which are spaced 6.5 fro each other to give a eat slice thickness of 5 per slice. It takes an average of 4 seconds to cut a slice and one hour for.673 tonnes. Keywords: Meat Slicing, Slicing Machine, Hygienic Slices, Slice Thickness. 1. INTRODUCTION Meat is the flesh of anials consued for food and it is a very iportant food delicacy that has been eaten since the existence of an. The consuption of eat along with other basic food is very iportant as it enriches both the nutritional content of the food and also acts as iportant delicacies. It is a nutritious food containing soe quantities of essential aino acids, in the for of proteins and also contains group of vitains. Anial eat is coposed of uscles, bones, fats and connective tissues, and the ain edible and nutritional part of the eat is the uscle or lean eat [1]. Therefore the eat has to be cut into large chunks, and then into bits and pieces so as to bring out the flavour and ake it in edible for. Meat is cut using various sharp instruents such as atches, knives and eat saw. These ipleents are only efficient in cutting the eat into chunks and de-boning but cannot cut the eat into sall bits and as a result of this, different achines have been developed over tie for slicing eat []. The principles of slicing achine is based on the action of shearing by blades and other types of cutters with sae principles as the slicing which include the ipact-type cutter, the ower cutter bar and the knife drive syste. A nuber of authors have studied the principles of slicing and slicing achines. Otto Rohwedder designed and anufactured the first slicing achine that would slice and wrap bread in 195 [3]. The first eat slicing achine was invented by an Aerican in 1873. The achine ade use of an oblique knife in a vertical sliding frae for slicing dry beef and it worked with the frae holding the eat while slicing it against the cutting blade [4]. The conventional slicing achine was originally designed to slice eat into pieces of unifor thickness. It was also used for slicing cheese, vegetables, ha, onions green peppers an sandwich ingredients [5]. There are basically three types of slicer; the gravity slicer, the horizontal slicer, and the bacon slicer and these three groups of slicer have their own shortcoing. The slicing achine for slicing food, such as eat, cheese, sausage and vegetable consists of a conveying device, a rotating blade and a knocking-off echanis for transferring the slices fro the conveying device to deposit area. [6] studied a vegetable slicing achine and divided the operations into four stages, consisting of aterial intake, aterial transission, aterial slicing and aterial ejection. He also stated that the vegetable slicing achine echanis is siply the action of shearing by the blades just like that of eat slicing achine.. PARTS AND OPERATION OF MACHINE The developed eat slicing achine was designed to slice eat in frozen for. It can accoodate one or ore cutting blades as required by the user. Fig. 1 shows the assebly of the eat slicing achine which works on the principle of a noral slicing achine. It is ade up of a frae on which on which are ounted, electric otor, the tray carriage, the eat feeder, the eat clap, the slide way which carries the slider in which a set of cutting blades are arranged. The cutting blades are spaced 6.5 fro each other to give a eat slice thickness of 5. Fig. shows the cutting blades arrangeent and the cross section of the eat hopper. The achine is designed to produce sooth and hygienic slices with a total ass of about 3.15 tonnes in one hour. This achine slicing capacity is anticipated with the assuption that the eat being sliced is boneless and in frozen for. It consists of the following ain coponents; the rotating disc cutter, the tray-carriage, the eat feeder, the eat clap and the control unit 0
International Journal of Engineering and Technology (IJET) Volue No., February, 01.1 THE ROTATING DISC CUTTER The rotating disc cutter is a flat disc ade of stainless steel aterial. It is 40 in outside diaeter with a bore of 15 diaeter and is coupled to an AC electric otor. The blade rotates at a speed of 100 revolutions per inute and it is shown in Fig. 3.. THE TRAY CARRIAGE The tray - carriage is the coponent that carries the eat to be sliced to the slicing point. It consists of a fraed part known as tray carriage ade of stainless steel that is used to carry and ove the eat towards the blade for slicing. It exhibits a reciprocating to and fro otion towards the blade for cutting to take place and this is shown in Fig. 4..3 MEAT TRAY The eat tray is the basin which collects the sliced pieces of eat during the slicing operation. It is ade of stainless steel to avoid corrosion and containation of the the sliced eat. The eat tray is shown in Fig. 5. (1) Cutting Blades Cage/Slider () - Cutting Blade (Ф 40) (3) - Slideway (4) - Machine Frae (600 X 50). (5) - Connecting Rod (6) - Crank Wheel (7) - Bearing Elevation (Section B-B) Figure 1. Plan and front view of the eat slicing achine. (8) Crank Shaft (9) Crank Pulley (10) Electric Motor (hp) (11) Machine Cover (1) Slice Collecting Bowl (13) Meat Feed Spring (14) Meat (15) Meat Hopper 03
International Journal of Engineering and Technology (IJET) Volue No., February, 01 100 Cutting blades spaced at 6.5 apart Reciprocating cutting blade edge 100 Hopper section 100 300 Figure. Cutting blades arrangeent and cross section of eat hopper Figure 3. Cutting blade 38 178 60 Rollers Figure 4. Tray carriage 04
International Journal of Engineering and Technology (IJET) Volue No., February, 01 84 108 190 Figure 5. Meat tray..4 Meat Feeder The eat feeder feeds the eat to be sliced towards the blade by pushing the eat out of the tray towards the blade. The eat feeder consists of a pusher and threaded screw length as shown in Fig. 6..5 Meat Clap The eat clap is a device that holds the eat to be cut in place. As the eat is fed out by the eat feeder, the clap is activated to hold and clap the eat in position for slicing. This is shown on the assebly of eat feeder, eat clap and tray carriage in Fig. 7. Feeder 84 Pusher Screw D.C Motor 108 10 Coupler Figure 6. Meat feeder Meat Tray Meat Feeder Thread Carriage Direction of Travel Meat Clap Figure 7. Assebly of eat feeder, eat clap and tray on the carriage 05
International Journal of Engineering and Technology (IJET) Volue No., February, 01.6 Operation of the Machine The eat to be sliced is loaded on the tray placed on the tray-carriage which oves the tray with the eat towards the blade for cutting. The eat feeder then oves the eat through a pre-set distance before the eat clap is activated to hold the eat in position for cutting. When the power source is switched on, the cutting blade begins to rotate while the required size of the eat to be cut is selected for the slicing. The eat feeder then feeds the selected size of the eat towards the cutter and stops autoatically A signal is then set to the eat clap to hold the eat to be sliced and the tray echanis oves quickly to the rotating blade which then cuts the eat into the pre-set slice sizes. After that the tray returns to its original position and as it stops, another signal is set to the eat clap to release the eat by pushing it towards the blade. It takes on the average about 4 seconds to cut a slice. The process continues until the whole eat is copletely cut into the required slices. 3. DESIGN ANALYSIS 3.1 Power Required for Slicing Operation In cutting processes, the power required for slicing is [7], where P = cutting power. P e = electric otor rating, = overall drive syste efficiency, P s = specific cutting energy Z w = aterial reoval rate, f e = feed per stroke of cutter, a c = undefored eat thickness, v = cutting speed. 3. Cutting Speed The cutting speed required for slicing is given by, V = Dn 60 Where V = cutting speed of blade, n = rotational speed of blade (rp), D = cutter diaeter. The speed of cutter is obtained fro equation (4) as, 60V n = D 3.3 Crank Mechanis of the Tray-Carriage (4) (5) P = P e (1) or P = P s Z w () while Z w = f a a c v (3) Fig. 6 shows the crank echanis which produces the reciprocating otion of tray-carriage that carries the eat and oves to and fro relative to the disc cutter. The displaceent, velocity and acceleration of the slider are now evaluated. Figure 6. Crank Mechanis for the Tray Carriage x R l R(1 cos ) sin (6) a d x R R (cos cos ) (8) dt l v dx R R (sin sin ) (7) dt l Where x = distance oved fro axiu end of dead centre, 06
International Journal of Engineering and Technology (IJET) Volue No., February, 01 v = velocity, a = acceleration l = length of connecting rod, R = crank length, = angular velocity of the crank, = crank angle, = connecting rod angle. 3.4 Turning Moent and Axial Load on Meat Feeder The turning oent and axial load on the eat feeder is obtained fro the relationship, f tan T w[ r ( cos ) fcrc ] tan 1 f cos Where T = torque applied to turn the eat feeder, w = load parallel to screw axis, r = ean thread radius, r c = effective radius of rubbing surface, f = coefficient of friction at collar, = helix angle at ean radius, = angle between tangent to tooth profile and a radial line. 4. THE THROUGHPUT OF THE MACHINE The achine capacity is deterined fro the ass of the sliced eat per unit tie. Fro the perforance of the achine, the tie taken for the carriage to ove to and fro the blade is 4 seconds and the thickness of each slice is 5, while the length of the slice is 108. Thus the cross section of the eat sliced by the blade is A = 10.8 x 0.5 c = 5.4 c The stroking rate of the to and fro the blade is S r = 15 strokes per inute, The feed rate of cutting the eat is f = 0.5 c /stroke. Therefore, the height of eat cut in one inute is H = S r x f = 7.5 c. Thus, volue of eat sliced in one inute is V = A x H = 40.5 c 3 The density of eat (at 75 percent oisture content), = 1100g/c 3. Thus, the ass of the eat cut per inute, (9) M = V x = 40.5 c 3 x 1100 g/c 3, = 44550g = 44.55 kg per inute. The ass of eat sliced in one hour, 5. CONCLUSION M = 44.5 x 60 kg. = 673 kg or.673 tonnes. Over the year, the traditional process of slicing eat has always been slow, tedious, boring, tie consuing and in soe cases unhygienic. The possibility of echanizing the process of eat slicing becoes very necessary. A eat slicing achine was therefore designed to echanize the process of slicing eat for both doestic and coercial consuption. The anufacture of the eat slicing achine involves the design and fabrication of soe principal coponents which include the tray-carriage, the disc cutter, the eat feeder, the eat clap and the control unit. Each part was carefully designed to eet the functional requireent of the achine, and different sizes of slices are obtainable by activating the eat feeder to give the desired sizes of sliced eat. The efficiency of the achine is quite encouraging as very sooth and hygienic slices are obtained and it takes on the average, about 4 seconds to cut a slice, while the ass of eat sliced in one hour is about.673 tonnes. REFERENCES [1] Ihekoronye, A.I. and Ngoddy, P.O., (1985). Cocoyas, in In Integrated Food Science and Technology for the Tropics. Macillan, London, UK, pp80 81. [] Charles, P. (001). Operational Principles of Soe Cutting Tools. International Journal of Machine Tools and Manufacture. Vol. 13, No. 8 47 53. [3] Frank, F. (004). Historical Albion Michigan, Albion History / Genealogy Resources. Morning Star, February 15, 004 pp16. [4] Hardin, C.W. (001): The Principles of Slicing Machines. Journal of Manufacturing Engineering. Vol.6, No. 13, pp 31-4. [5] R. Tannahill, R. Food in History. 5th Edition, Three Rivers Press, New York, (003). [6] Odior, A.O., Oyawale, F. A. and Orsarh, E. S. (009): Developent of a Vegetable Slicing Machine fro Locally Sourced Materials. The Journal of the 07
International Journal of Engineering and Technology (IJET) Volue No., February, 01 Nigerian Institution of Production Engineers. Vol. 11, No. 1, pp 143 156. [7] Boothroyd, J. Mechanics of Machining and Machine Tool Technology, McGraw-Hill Book Copany, New Delhi, (1985). 08