THE DRAW ROTARY ENGINE

Abstract: A reciprocating piston rotary internal combustion engine; comprising a non-rotating circular cylinder engine block (16) containing a rotor (21) on which piston (32) reciprocate at right angles to the direction of centrifugal force, and parallel with the rotor, and at right angles to the direction of rotation of the rotor. These pistons form three sides of the combustion chamber (36) and the combustion chamber ignition blocks (24), (which are built on to the rotor (21)) along with rotor (21) form two more sides, finally the cylinder (16) forms the sixth side. Compression and decompression is affected by cams (28) on front and back plates (27) guiding pistons (32) by means of cam followers (33) built into the pistons. By altering cams (28) one can produce variable delays (pauses (37)) between the strokes of the combustion cycle or change the number of strokes in a given combustion cycle. The rotor (21) can have the blanks (23) recessed to allow for counterbalances to be inserted, and pistons (32) can have guide rails added to take the counterbalances.

Description: The Draw Rotary Engine. This invention relates to an internal combustion rotary engine, either spark ignition or fuel injection. Internal combustion rotary engines are well known and there are four general categories; (1) Cat- and- Mouse ( or scissor ) engines; (2) Eccentric- rotor engines; (3) Multiple- rotor engines; (4) Revolving block engines, which combine reciprocating piston and rotary motion. The problems with Cat and Mouse engines were stop and go forces, gas seal and lubrication. The problems with eccentric - rotor engines were retained burnt gases reducing engine performance and pollution of the air. Multirotor engines have low efficiency, difficulty sealing and high rubbing velocities. The revolving engine block engine's biggest problem, is the revolving engine block. According to the present invention there are provided reciprocating pistons ( any number of ) laid on a rotor. The pistons rotating concentrically with the rotor, inside a annulus formed by the rotor and a non-revolving circular cylinder engine block with means of ignition and inlet and exhaust of gases. The rotor may or may not have recesses for the purpose of housing counterbalance weights to the pistons, counterbalance weights would be attached to the rotor. The pistons reciprocate along the length of the rotor, parallel with the rotor, at right angles to the direction of rotation of the rotor, and are known as Draw pistons. The cam following Draw pistons are arc shaped over their width, and straight over their length with a hollow centre, and may or may not have in depth a guide rail attached for the purpose of being counterbalanced. A Draw piston forms three sides of a combustion chamber, the rotor with built in combustion chamber ignition blocks forms two more sides, finally the circular cylinder engine block forms the sixth side. Draw pistons drive their rotor forward by pushing against it. The Draw piston's motions of compression and decompression are guided by cams and the pistons reciprocate on a path at right angles to the direction of the rotor's centrifugal force. The cams are situated on the cylinder's front and back plates. The cams can give the pistons a four or six stroke combustion cycle, with one or more cycles per revolution. The fifth and sixth strokes are used as a flushing stroke and second exhaust stroke, and for cooling purposes. The cams can also allow pauses of variable lengths ( degrees ) between strokes, to allow for combustion time lags and inlet and exhaust time lags. The pistons are held by the rotor in the direction of rotation, and either by the cylinder engine block against the direction of centrifugal force, or by a part of the rotor, or by counterbalance weights against the direction of centrifugal force. Draw pistons require a special centrifugal device for their inner piston rings, to maintain a gas tight seal in the opposite direction of the centrifugal force. The centrifugal device is heavier at one end than the other, either pivoting on part of the piston, or rotating on a shaft, so that the centrifugal force pushes out the heavy end in the direction of the centrifugal force, and forcing the lighter end, and thereby the piston ring it is in contact with, in the opposite direction to the centrifugal force, affording a gas tight seal, equal or proportionate to, the centrifugal force. A vanned fixed rotor on the main rotor's shaft, opposed to a stationary fixed vanned rotor on the cylinder's front or back plate supplies either oil or air pressure for lubrication. A specific embodiment of the invention will now be described by way of example, drawn free hand as a representation and not to any scale, of a three piston six chambered version, with reference to the accompanying drawings, in which;- Figure 1 shows in perspective the circular cylinder block. Figure 2 shows in perspective the basic rotor. Figure 3 shows the side view of the two cammed four stroked cycle, without pauses, front or back plate. Figure 4 shows the inside face view of a two cammed four stroked cycle, without pauses, front or back plate. Figure 5 shows a representation of the centrifugal device for the inside piston ring or rings. Figure 6 shows an end view (arc) of the basic Draw piston. Figure 6a shows an end view (arc) of the Draw piston with counterbalance rail. Figure 7 shows a top view of the basic Draw piston. Figure 7a shows a side view of the Draw piston with counterbalance rail. Figure 8 shows a cross-sectional representation of Draw Rotary Engine. Figure 9 shows a representation of the working parts unrolled and laid out flat, of a four stroked cycle version without pauses. Figure 10 shows a side view of the two cammed four stroked cycle, with pauses, front or back plate. Figure 11 shows the inside face view of a two cammed four stroked cycle, with pauses, front or back plate. Figure 12 shows a representation of the working parts unrolled and laid out flat, of a four stroked cycle version with pauses . Figure 13 shows a side view of a three cammed six stroked cycle, with pauses, front or back plate. Figure 14 shows the inside face view of a three cammed six stroked cycle, with pauses, front or back plate. Figure 15 shows a representation of the working parts unrolled and laid out flat, of a six stroked cycle version with pauses. Figure 16 shows an end view of a rotor with recesses for counterbalances. The Draw pistons with counterbalance rails, and the counterbalances in position. Figure 17 shows a counterbalance weight. Referring to the drawings; the Draw piston rotary engine comprises a non moving circular cylinder engine block 16 with a hole for spark plug or fuel injecter 17 and holes for bolts 18 with inlet ports 19 and exhaust ports 20. Inside this fits a rotor 21 with shaft 22 on the shaft is fitted the rotating half a vanned rotor pump 26 for lubrication purposes. There are blanks 23 on the rotor's surface, such blanks depend on the number of pistons desired or engine block circumference desired. Also on the rotor's surface is the combustion chamber ignition blocks 24 with ignition recess 25 around which the pistons 32 fit. At either end of the circular cylinder engine block fits the front and back plates 27 both identical and doing the same job. On these front and back plates are the cams 28 with heads 29 and bases 30. These cams guide the reciprocating pistons and may or may not have pauses 37, these flat areas (pauses) on the heads and bases of the cams allow for delays of variable length (degrees) between reciprocating strokes. Also on the plates 27 are the bearing holes 31 through which the rotor shaft 22 fits and bolt holes 18 to secure it to the circular cylinder block 16. The second non rotating half of the vanned rotary pump 26 is fitted to the plates as well. The pistons 32 have at their ends cam followers 33 which when in contact with the cams drive the rotor foreword in the direction of rotation and guide the pistons reciprocating motions across the surface of the rotor 21 with the combustion chamber ignition blocks in between the pistons affording compression and decompression, forming the combustion chamber 36. A gas tight seal is achieved by device 35 pushing piston ring 34 in the opposite direction to the centrifugal force. The blanks 23 can be recessed 40 to take counterbalance weights 38 held by pins 41to rotor body 21 and pistons 32 can have guide rails 39 added to take the counterbalance weights.

Claims: Claims. 1. A rotary engine comprising reciprocating pistons ( any number of ) held on a rotor, the pistons rotating concentrically with the rotor, inside a annulus formed by the rotor and a non revolving circular cylinder engine block with means of ignition and the inlet and exhaust of gases. The rotor may or may not have recesses for the purpose of housing counterbalance weights to the pistons, counterbalance weights would be attached to the rotor. The pistons reciprocating at a angle along the length of the rotor, parallel with the rotor, at right angles to the direction of rotation of the rotor. The piston forms three sides of a combustion chamber, the rotor forming two more sides, finally the circular cylinder engine block forms the sixth side. The pistons drive their rotor forward by pushing against it. The piston's motions of compression and decompression are guided by cams and the pistons reciprocate on a path at right angles to the direction of the rotor's centrifugal force. The cams are situated on the circular cylinder engine block's front and back plates. The pistons are held in position by the rotor in the direction of rotation, and by either the circular cylinder engine block, or by counterbalance weight against the direction of centrifugal force, or by part of the rotor against the direction of centrifugal force, or any combination of the above. 2. A reciprocating piston rotary engine as claimed in Claim 1 wherein the cams situated upon the front and back plate of the circular cylinder engine block can vary in number, size, position and shape, to allow for the reciprocating pistons to have a two, four or six stroke combustion cycle, with one or more cycles per revolution of the rotor. The fifth and sixth strokes could be used as a flushing stroke and second exhaust stroke, and for cooling purposes. 3. A reciprocating piston rotary engine as claimed in Claim 1 or Claim 2 wherein the cams can vary in number, size and position and shape to allow for the pistons to pause for variable lengths ( degrees ) between strokes of a combustion cycle, to allow for combustion time lags and inlet and exhaust time lags. 4. A reciprocating piston rotary engine as claimed in Claim 1 or Claim 2 or Claim 3 wherein the cam following piston is arc shaped over it's width, and straight over it's length, which may or may not have in depth a rail attached for the purpose of being counterbalanced, and with cam followers at it's ends and with a hollow centre. A piston forms two combustion chambers alternately while reciprocating across the length of the rotor, around the combustion chamber ignition block. 5. A reciprocating piston rotary engine as claimed in Claim 1 or Claim 4 wherein a centrifugal device fitted within the piston, which is heavier at one end than the other, either pivoting on part of the piston, or rotating on a shaft. So that the centrifugal force pushes out the heavier end of the device in the direction of the centrifugal force of the piston, and forcing the lighter end of the device, and thereby any piston ring it is in contact with, in the opposite direction to the centrifugal force of the piston affording a gas tight seal, equal or greater than the centrifugal force of the piston. 6. A reciprocating piston rotary engine substantially as described herein with reference to Figures 1-17 of the accompanying drawings.

Inventors: LEATHWAITE MALCOLM, LEATHWAITE, MALCOLM
Applicants: LEATHWAITE MALCOLM, LEATHWAITE, MALCOLM
Application year: 1999
Main classification: F02B75
IPC codes: F01B3, F02B59, F02B75, F02F1