GB2273317A

GB2273317A - Rotary motor or pump.

Info

Publication number: GB2273317A
Application number: GB9321528A
Authority: GB
Inventors: John Moore
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-12-08
Filing date: 1993-10-19
Publication date: 1994-06-15
Anticipated expiration: 2013-10-19
Also published as: GB2273317B; GB9321528D0

Abstract

A motor or pump with two or more pistons 1 - 3 each rotatable about an associated spindle 7 - 9 and having an operative surface of non-circular shape and comprising a plurality of intersecting curves 10 - 21, 22 - 33 so constructed that on operation of the motor or pump with the pistons rotating in the same direction and at the same speed the surfaces of adjacent pistons are able to maintain continuous physical contact with each other. The pistons 1 - 3 are housed in cylinders 4 - 6 with adjacent cylinders intersecting and communicating with each other, each cylinder having a radius equal to the maximum radius of the associated piston, the design enabling the pistons to rotate synchronously through intersecting swept volumes. A preferred design of pump has two pistons (Figs. 6, 7 and 8). A four piston design of motor (Figs 9a - d) produces an efficient volumetric configuration. <IMAGE>

Description

ROTARY MOTOR OR PUMP This invention relates to motors or pumps incorporating rotary pistons.

According to the present invention there is provided a motor or pump including at least two pistons each rotatable about an associated spindle extending axially and centrally of the piston, the pistons each having an operative surface of non-circular shape and comprising a plurality of intersecting curves, a transverse section through each piston having major and minor axes, said surfaces being so constructed that, on operation of the motor or pump, the pistons rotate in the same direction and at the same speed about their associated spindles with the surface of adjacent pistons maintaining continuous physical contact one with the other. the major and minor axes of a piston at all times being perpendicular to the corresponding major and minor axes of the other or each adjacent piston.

The pistons may each be housed in associated cylinders, adjacent cylinders intersecting one another to communicate one with the other, the radius of each cylinder being equal to the maximum radius of the associated piston.

By way of example only, embodiments of the invention will now be described in greater detail with reference to the accompanying drawings Fig. 1 is a schematic vertical section through a first motor or pump of the invention: Fig.2 is a section on the centre line of Fig.1; Fig.3 illustrates the geometric construction of the curves of two adjacent quadrants of pistons of Fig.1; Fig.4 illustrates the formation of adjacent pistons with certain angles and curves reduced to zero; Fig.5 shows the sequence of operations of a motor of the invention as illustrated in Fig. 1; Figs.6,7 & show alternative configurations of pumps of the invention utilising two rotary pistons contained in cylinders with various examples of inlet and exhaust ports.

Fig.9 shows a sequence of operations of an alternative configuration of a motor or pump of the invention utilising four rotary pistons either contained or not contained in cylinders.

Refering to Figs. 1 and 2, the motor or pump is of generally known configeration but comprising three rotary pistons 1,2 and 3, constructed as described later in conjunction with Fig.3, rotating in the associated intersecting cylinders 4, 5 and 6 on spindles 7. 8 and 9. The distances between the spindles 7 and 8, and 8 and 9 are equal.

The two smaller pistons 1 and 3 are identical in shape and size. The larger centre cylinder 5 is intersected by the two smaller cylinders 4 and 6.

which cylinders are of equal diameter.

Each of the pistons has an operative surface comprising 12 intersecting curves (10 to 21 on pistons 1 and 3, and 22 to 33 on piston 2). The pistons further comprise opposed. flat end faces (34, 35 on pistons 1 and 3 and 36. 37 on piston 2). The pistons are adapted to rotate in the same direction within their cylinders and are kept in step by main gears 38. 39, 40 coupled by idler gears 41, 42. End plates 43, 44 maintain the pistons 1,2 and 3 in position within their associated cylinders, which plates form a seal to said cylinders.

When the device is used as a rotary motor, inlet and outlet ports 45, 46 are provided in the small cylinder 6 and when used as an internal combustion engine a spark plug is provided at an appropriate position in the small cylinder 4. On synchronous rotation of the pistons in a clockwise direction as viewed in Fig. 1. fuel mixture is drawn into space 48, transfered to space 49 under compression and, after ignition, is expanded into space 50. The piston 3 separates the induction cycle from the exhaust cycle.

Here particularly, the sequence of operation of an internal combustion engine of the invention is shown in Fig.5 where the pistons are again rotating in a clockwise direction.

Fig.5a shows the positions of the pistons at the commencement of induction at V and compression in W.

Combustion is taking place at X and exhaust at Z.

Fig.5b shows the progression of the cycle with expansion taking place at Y.

Fig.5c shows the position where compression into W is complete, expansion having taken place into Y and exhaust about to commence at Z. The induction volume is now at a maximum and from this point all volumes remain comparatively constant as the system passes through the state shown in Fig.5d to return to the position illustrated in Fig.5a. Induction continues during the constant volume period and the exhaust cycle will be a continuation of gas flow and expansion. Ignition takes place during the period of constant volume.

When the device is used as a rotary pump, suitably positioned inlet and exhaust ports may be added to cylinder 4 of Fig.1: or alternative configurations may be used, examples of which are shown in Figs. 6.7 and 8, which each comprise two rotary pistons of the invention incorporated in two cylinders with inlet and exhaust ports suitably placed, either directly in the cylinder walls or through ducts in the rotary pistons.

In each case non return valves may be fitted to prevent reverse flow of fluids and in the case of the example shown in Fig.7, fluids may bypass the small rotary piston in the general direction of flow by a suitable duct or by modification of the profile of the small rotary piston.

The following is one method of constructing the curved surfaces of two adjacent rotary pistons of the example with reference to Fig.3. Two adjacent quadrants are dealt with and the remaining quadrants can be constructed in the same way although it is not necessary for each rotary piston to be symmetrical in shape.

Construct a quadrilateral ADBC with sides approximately in the required ratio of the major axes of the two adjacent rotary pistons. Join AB. Points A and B will be the centres of their respective rotary pistons which will be referred to as pistons A and B.

Construct a circle with centre B and an arbitary suitable radius less than BC. This radius will be half the length of the major axis of piston B.

Construct < EBC and < FBC such that arc EF forms part of the periphery of the piston B and is of an arbitary desired length. On piston A, construct < DAH equal to < EBC and < DAG equal to < FBC. On piston A construct < KAC and < LAC in a like manner and on piston B, construct < MBD equal to < KAC and < NBD equal to < LAC.

Choose a point P on EB to give a suitable arbitrary radius for curve ER. Draw a line through P parallel to AB and cutting the extension of HA at J and the extension of MB at O. It will also intersect AK at S. With centre P and radius PE construct an arc from E joining SP at R and with radius SR construct an arc from R joining AK at T. With centre A and radius AT construct an arc meeting AL at U. Arcs ER, RT and TU form parts of the periphery of their respective pistons and AT is now the determined length of the major axis of piston A.

With centre 0 and radius OR (which equals AB-SR), construct arc RV and with centre B and radius BV construct arc VW. Similarly with centre J and radius JR (AB-RP) construct arc RH and with centre A and radius AH construct arc HG. Arcs RV, VW, RH and HG form part of the periphery of their respective pistons.

The remaining quadrants of the pistons can now be determined in a similar manner.

It will be appreciated that as < EBC on piston B in Fig.3 is decided arbitrarily, the angle may be reduced to zero, in which case point P will fall on the major axis BC and curve RE will also extend to the major axis eliminating part of the curve EF. In this case, the corresponding angle HAD and the curve that subtends it will also be reduced to zero. If we proceed to symmetrical construction of the pistons, each piston will be reduced to four intersecting curves as in Fig.4.

By way of further example, Fig.9 shows a sequence of operations of a motor or pump constructed with four pistons of the invention, each piston having, for simplicity of demonstration, four intersecting curves, as illustrated in Fig.4, the pistons so arranged that each maintains continuous physical contact smith each adjacent piston. Pistons rotate synchronously with their major axes always perpendicular to the major axis of each adjacent piston. Fig.9a shows the commencement of a cycle with induction taking place at K through a suitably placed port. Induction continues in Fig.9b at L and reaches a maximum in Fig.9c at M. When used as a pump exhausting of the fluids will commence through a suitably placed exhaust port and continue by contraction of volume N in Fig.9d, and returning to the original position in Fig.9a.When used as a motor with a four stroke cycle, Fig.9d depicts the progress of a compression cycle with ignition at Fig.9a and a second rotation to include the expansion and exhaust cycle.

Adjacent pistons constructed in various forms following the method described above, when rotated in the same direction and at the same speed, and with their major axes always perpendicular to each other, will maintain continuous physical contact with each other.

Curves 10,11,22,23 in Fig.1 forming the piston tips, having a radius equal to the radius of their associated cylinders, will also be in contact with the associated cylinder wall during part of the rotation of their pistons.

It will be seen that the invention provides a system of two or more rotary pistons of a design which enables them to rotate synchronously through intersecting swept volumes in such a manner that adjacent pistons maintain continuous physical contact with each other.

The periphery of each piston consists of a series of intersecting curves such that, with adjacent pistons rotating in the same direction and with their major axes remaining perpendicular to each other the following conditions will apply: a) All intersecting curves on one piston have a common tangent at their points of intersection and a common tangent with an adjacent piston at any point of contact with an associated curve of that adjacent piston.

b) Each curve on the one piston will have a radius equal to the distance between the centres of the relevant adjacent pistons minus the radius of the associated curve on the adjacent piston. (i.e. RO=AB-SR and VB=AB-AT).

c) Any curve comprising part of the operative surface of the one piston will whilst part of the surface of that curve is in sliding contact with the surface of an adjacent piston, have a progressive point of contact which follows a curve on the said surface of the adjacent piston that is an arc of a circle having a radius equal to the distance between the centres of rotation of the two pistons minus the length of the radius of the said curve comprising part of the operative surface of the one piston.

d) Associated curves will subtend equal angles at their centres. (i.e. < RST= < ROV and < TAC= < VBD)

Claims

CLAIMS What I claim is:

1. A motor or pump including at least two pistons each rotatable about an associated spindle extending axially and centrally of the piston, the pistons each having an operative surface of non-circular shape and comprising a plurality of intersecting curves, a transverse section through each piston having major and minor axes, said surfaces being constructed as described and illustrated by Figs. 3 and 4, so that, on operation of the motor or pump, the pistons rotate in the same direction and at the same speed about their associated spindles with the surfaces of adjacent pistons maintaining continuous physical contact one with the other, the major and minor axes of a piston at all times being perpendicular to the corresponding major and minor axes of the other or each adjacent piston.

2. A motor or pump as claimed in claim 1, including at least two rotary pistons each rotatable about an associated spindle and each having an operative surface of non circular shape and comprised of or mainly comprised of a plurality of intersecting curves constructed as described with reference to and as illustrated by Figs.3 and 4, so that on operation of the motor or pump, the surfaces of adjacent rotary pistons maintain physical contact one with the other for a substantial part of their rotation such physical contact to include near physical contact allowing for engineering tollerances and operational clearances.

3. A motor or pump as claimed in claims 1 and 2 in which the pistons are each housed in associated cylinders, adjacent cylinders intersecting each other to communicate one with the other, the radius of each cylinder being equal to the maximum radius of the associated rotary piston.

4. A motor or pump as claimed in claims 1,2 or 3 in which the operative surfaces of each piston are either symmetrical or non-symmetrical about the associated spindle.

5. A motor or pump as claimed in any one of claims 1 to 4, in which the pistons are constructed as described with reference to and as illustrated by Figs. 1 to 9, or by a combination of said figs. 1 to 9 of the accompanying drawings.

6. Motors or pumps substantially as described herein and illustrated by Figs. 1, 2, 5, 6, 7 and 8 and incorporating pistons as described herein with reference to and as illustrated by Fig. 3.

6. A motor or pump as claimed in any one of claims 1 to 4, in which the pistons are as illustrated in Figs. 1 to 9 of the accompanying drawings

7. Motors or pumps substantially as described herein with reference to and as illustrated by the accompanying drawings.

Amendments to the claims have been filed as follows

1. A motor or pump including at least two pistons each rotatable about an associated spindle extending axially and centrally of the piston, the pistons each having an operative surface of non-circular shape and comprising a plurality of intersecting curves, a transverse section through each piston having major and minor axes, said surfaces being constructed as described and illustrated by Fig. 3, so that, on operation of the motor or pump, the pistons rotate in the same direction and at the same speed about their associated spindles with the surfaces of adjacent pistons maintaining continuous physical contact one with the other, the major and minor axes of a piston at all times being perpendicular to the corresponding major and minor axes of the other or each adjacent piston.

2. A motor or pump as claimed in claim 1, including at least two rotary pistons each rotatable about an associated spindle and each having an operative surface of non circular shape and comprised of or mainly comprised of a plurality of intersecting curves constructed as described with reference to and as illustrated by Fig. 3, so that on operation of the motor or pump, the surfaces of adjacent rotary pistons maintain physical contact one with the other for a substantial part of their rotation such physical contact to include near physical contact allowing for engineering tollerances and operational clearances.

5. A motor or pump as claimed in any one of claims 1 to 4, in which the pistons are constructed as described with reference to and as illustrated by Fig. 3, and incorporated in motors or pumps as decribed and illustrated in Figs. 1, 2, 5, 6, 7 and 8 or by any combination of Figs. 1, 2, 5, 6, 7 and 8.