~2372~4 This invention relates to a can opener. More specifically it rela~es to the driving means used for the feed mechanism and cutter mechanism in a can opener. It is an object of the invention to provide a cutter means and feed means on the same shaft with the power applied directly to the said shaft. More particularly, it is an object of the invention to provide a cutter means and a feed means which can be varied as in a continuously variable clutch, without the use of gears, by the use of a gripping groove which engages the top rim of the can and a smooth-rimmed free-rotating pressure wheel which engages the bottom rim of the can bead. It is a further object of the invention to provide a means for the quick and easy removal of the cutter from the can opener for the purpose of washing said cutter without difficulty and without washing the lubricants fro~ the bearings in the can opener. The invention provides a means of replacing the cutter in a firm position after cleaning. At present, all power driven can openers, be they hand-operated or electrically-operated, employ a jagged-toothed feed wheel which bites into the bottom lip of the bead on the can and to which the power is applied. The power is then indirectly transmitted to either a knife-like blade or a cutting wheel. Some can openers employ a pair of gears to transmit the power from the feed wheel to a cutting wheel. Because the cutting and feed action are directly powered, my invention requires less power to operate without the use of gears. The use of the clutch can make the operation even easier. Only smooth surfaces make contact with the bead on the can, top and bottom, resulting in a smoother operation. The clutch feature is of great value to those with physical problems of the hands, especially arthritis sufferers. The clutch also makes the invention particularly suitable for electrically driven can openers. ,~,y~ ~Z37274 Because the crank on the manually operated version of the invention is set at an angle of approximately 20 instead of vertically, as with other can openers, the right hand is in a slightly more natural position for rotating the crank, thereby making the operation easier. Because the cutter is wedged tightly against the inside wall of the can, the finished cut is clean and leaves the peripheral edge of the can pressed tightly against the inner surface of the side wall of the can. .~ Can openers observed by the inventor in most households are extremely dirty and could be a breeding ground for harmful bacteria. This invention provides for a simple method of keeping the cutter clean. This invention provides a can opener which is much more efficient than prior openers of this type, and yet, because of the simplicity of the embodiments, it may be manufactured at a relatively low cost. In the accompanying drawings which illustrate embodiments of the invention, Figure 1 is a side elevation of a hand-actuated can opener shown in open position. Figure 2 is a vertical section through the can opener, taken on the line 2-2 in Figure 1. ~0~9O,,~l A Figure 3 is a side elevation, from the rear, of the ~~-r~ feed wheel and cutting wheel. In operation, the gripping groove 4 is placed on the top lip of the can to be opened. When the upper handle 8 and lower handle 13 are closed with the left hand, the pressure wheel 16 which is a smooth-rimmed free-rotating wheel engages the bottom lip of the can bead. The crank 11 is turned in a clockwise direction with the right thumb and forefinger. With a little pressure applied with the left hand, the first part of the turn causes the cutting wheel 3 to puncture the can. Continued pressure on the handle causes the top of the can lip to be wedged into the gripping groove 4 and the cutting wheel 3 to be driven in a forward direction as the crank 11 is turned. . Pressure applied by the left hand is important. Sufficient pressure must be applied to prevent the cutter 3 from riding up on top of the can lid. Beyond that, the left hand pressure on the handles 8 and 13 controls the forward drive of the cutter 3 and hence the amount of power required of the right hand to rotate the crank 11. This is a natural and simple operation based on the ordinary feel of the hands. The equivalent amount of left hand pressure as is required to operate any other hand-actuated can opener will cause the cutter 3 to be driven forward in a positive manner. That is, without any slipping action. In this event, the power required from the right hand will be approximately equal to that re~uired to turn the crank oE the better made can openers, with gears, currently being marketed. However, when required, the pressure of the left hand can be eased which will cause the gripping groove 4 to slip somewhat on the can lip, thereby making the turning of the crank 11 easier. This left hand action can be varied to any degree, except as already indicated, thus converting the gripping groove 4 into a continuously variable clutch. To remove the cutter 3 for cleaning~ close the handles fully, with no A can in the way, causing the oclt~gonal feed wheel to lock against the flange 18. Turning the crank 11 in a counter clockwise direction will cause the feed wheel 5 and with it the cutter 3 to be unscrewed and removed. To replace, screw unit back on, close handles and turn crank clockwise until tight. The can opener includes an upper handle 8, a lower handle 13 and a pivotal stud 20 which hinges the two handles. Handles can be of any reasonable design. The upper handle 8 has a forwardly and downwardly stamped portion 7 upon which is mounted a bearing 9 downwardly inclined towards the centre of the can at an angle of approximately 20 from the horizontal. The bearing 9 contajns a driving shaft 10 upon one end of which is mounted a crank 11. At the other end, the shaft 10 has a reduced threaded portion 12 on which ~Z37274 -- 4 -- is tightened a lock nut 6 to retain the shaft 10 within the bearing 9. Also screwed onto the shaft 10 is the feed wheel 5 and cutting wheel 3, which is one integral unit, forming the gripping groove 4. For the purpose of removing the cutting wheel 3, which operation is explained later, the feed wheel 5 is polygonal in shape. The cutting wheel is machined at an angle of approximately 20 from the vertical to match the inclination of the driving shaft 10 to which said cutting wheel is attached, thereby keeping the inside face of the cutting wheel parallel with the upper handle 8. Providing the thrust for the variable clutch is the pressure wheel 16 which is a smooth-rimmed wheel rotating freely around a stub shaft 14 fixed to the lower handle 13. The bearing 15 is an integral part of the pressure wheel. To retain the pressure wheel, the stub shaft 14 is lightly riveted at its outer end 17 where no pressure is applied. An important feature of the can opener is the fact that the stub shaft 14 is fixea at an angle of some 5 downward from its outer end to the lower handle 13. The effect of this, is a tilting of the pressure wheel 16 so that the bottom circumference of said pressure wheel stands away from the side wall of the can while the top circumference rides under the lip of the can bead. The purpose is to eliminate any possible friction between the face of the pressure wheel 16 and the can wall. The flange 18 is stamped out from the lower handle 13 to leave a gap 19 in Figure 1. Said flange is set downward, at its outer end, at an angle of approximately 20 or parallel with the polygonal end of the feed wheel 5. Function of the flange is to provide a lock for the feed wheel so that when the crank 11 is turned in a counter-clockwise direction, said feed wheel and cutter wheel 3 will unscrew for cleaning. The flange 18 is positioned just above and behind the pressure wheel 16 so that it is low enough not to touch the feed wheel 5 when a can is in the can opener but high enough to make firm contact with the polygonal edge of the feed wheel 5, when the handles are closed, with no can in the way. lZ37274 A bottle opener may be cut into the lower handle. This can opener can be used as would a pair of scissors or cutters. That is~ without the necessity to rotate the crank 11. A ball--filled bearing could be substituted for the pressure wheel 16. However, this will likely increase the manufacturing cost with little or no increased efficiency. For manufacturing pur?oses the cutting wheel and feed wheel, which are shown as one integral unit, may be made in two separate parts, neces- sitating slight modifications in order to unscrew the feed wheel.