GB2139704A - Rotary positive displacement machines - Google Patents

Description

SPECIFICATION Rotary prime movers and positive displace- ment pumps 1, Aylmer James Martinus Aldwinckle, of Pin Farm, South Hinksey, Oxford, England, a British subject, do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement: My invention constitutes a concept of rotary aspirating machines in which working media such as air, steam, gas or other fluid mixtures are worked upon or work in volumes of variable capacity by curved vanes oscillating within tracts of rectangular cross section.

The outer bodies of these machines contain the tracts of variable capacity and are formed by a series of laminations consisting of paral- lel tract plates, sideplates and endplates held together by a number of tension members passing at right angles to, and through the parallel plates.

This type of construction enables conventional machine tools to be used and the simplicity of the design will permit low costs of manufacture.

Rotary machines previously designed for similar functions have embodied lobes which have been termed rotary pistons while others have used sliding and/or oscillating vanes, but in any like machines where such components perform the function of a piston, it is preferable they should not be so termed as pistons are designed to function in cylinders, and the term'rotary piston'is therefore misleading.

The fundamental components of this invention applicable to all rotary machines envisaged are tracts formed by tract plates and sideplates in which pivoted or rocking vanes function.

These vanes are hitherto refered to as rocking vanes, abreviated for convenience to R/V's.

Broadly, the form of the R/V is a curved component, pivoted at one end and having a pivoted tip member at the other end.

The curvature is in the length of the R/V, the sides are straight and parallel, the width being the same as the width of the accommodating tract, and the depth tapers from the pivot end towards the tip member.

The R/V's in accordance with this invention lie in tracts formed in plates of the same width as the R/V's and have sideplates on either side.

The tract in each tract plate is the result of an eccentric circle or other profile form cut from the full width of the tract plate, the inner surface of which forms the peripheral surface of the tract.

The tract plates and the sideplates together with the endplates in which the bearings of the machine are located, comprise the series of parallel plates or laminated assembly already refered to in this specification.

The R/V's functioning within their tracts have been designed to operate either as pumps or as prime movers.

When operating as pumps the R/V's lie in eccentric tracts and the relative movement of R/V to tract is contra to the direction of R/V cuw ature and depth taper from the R/V pivot pin. This relative movement applies whether the outer body of the pump rotates or is stationary.

The body of the compressor consists of a laminated assembly of plates being the endplates containing the bearings of the machine and between these, the alternate tract plates and sideplates according to the number of tracts for the particular machine. However, a small version of pump with a stationary outer body may have only one tract plate between endplates and bearings.

When the body assembly rotates contra to the curvature and taper of R/V's, the relative movement between tract surface and R/V is such that the R/V tip is leading and the R/V pivot pin trailing.

When the outer body is stationary, the rotor carrying the R/V's pivoted thereto rotates also with the R/V tips leading. In this case air delivery valves and intake ports may be positioned in the side or endplates of the pump, as differing from the valves in rotating outer body pumps which pass compressed air or gas into a central hollow shaft.

The R/V's are provided with light springs which keep the R/V tips in contact with the tract peripheral surface when pivoting outwards. As relative movement takes place the eccentric surface of the tract forces the R/V to pivot inwards. The pivoting tip of the R/V is in itself a pressure operated seal, and the sides of the R/V also have pressure operated seals.

In rotating body pumps air or gas is drawn through radial ducts formed between the tract peripheral surface and the outer surface of the tract plate.

In stationary body pumps air or gas is drawn through ports or grilles located in the side or endplates of the pump.

In either case the ducts, ports or grilles for air or gas entry are so positioned that the relevant R/V will have closed such openings when that R/V begins to pivot inwards under pressure of tract piate eccentric surface.

At the point of minimum eccentricity for each tract plate, a conventional spring pressure seal is provided across the full width of the tract.

A tract plate may have one, two or more R/V's and a complete machine may have one or more tract plates.

Certain applications envisaged for this in vention require the axis of rotation, when in the form of a compressor, to be vertical instead of horizontal, therefore the rotational axes of compressors according to this invention may be vertical or in any other plane.

Having described the function of R/V's in tracts operating as pumps, the other versions of the aspirating rotary machines in accordance with this invention, are prime movers.

As a rotary steam motor this invention consists of a stationary outer body comprising the laminated assembly of plates previously described, with an inner rotor carrying the R/V's which lie in tracts and between sideplates as already described.

In this case the inner peripheral surfaces of the tract plates are not in the form of eccentric circles but have profiles designed to obtain optimum benefit of steam expansion and are offset in relation to the central axis.

The essential feature for prime movers in accordance with this invention is that relative movement between R/V and tract surface is opposite to the relative movement when functioning as pumps, which means that for prime movers, the pivot end of the R/V is leading and the R/V tip trailing within a stationary outer body.

For the steam motor the width and depth of tracts differ one from another and the sideplates between tracts incorporate ports designed to permit optimum transfer of steam from one tract to an adjacent tract.

In the design of a three tract steam motor according to this invention, the machine would be a triple expansion rotary steam motor. The steam would be admitted to the first tract either via a tangential port or via ports in the rotor and hollow central shaft similar to the air motor or interna combustion engine application of this invention. Thus the first tract is the high pressure tract and within the tract may be one or more R/V's, but for steam, preferably three, each being attached to the rotor by its pivot pin at an angular separation of 120 . When one of the high pressure R/V's has moved through approxi- mately 120 under pressure of throttle admitted steam, it uncovers a port in the sideplate allowing the steam to pass into the adjacent intermediate pressure tract. The width and depth of this tract are greater than those of the high pressure tract.

The intermediate tract has the same number of R/V's lying in it similarly attached to the rotor by their pivot pins, but at positions a number of degrees in advance of those in the high pressure tract. When the sideplate port is uncovered, the relevant R/V in the intermediate pressure tract (hereafter referred to as the IP tract) is in a position to receive the benefit of the steam entering from the high pressure tract (hereafter referred to as the HP tract).

Meanwhile the next or following R/V in the HP tract is under the influence of a fresh volume of steam whiist the back or leading side of the same HP R/V is scavenging the tract ahead of it into the adjacent IP tract via the open port in the sideplate.

The third plate in this design is the low pressure tract (hereafter referred to as the LP tract), the width and depth of the tract being again greater than those of the adjacent IP tract. This LP tract also accommodates the same number of R/V's as in the adjacent two tracts, and here again the R/V's are attached to the rotor by their pivot pins but advanced a number of degrees to the R/V's in the IP tract so that the relevant R/V in the LP tract receives the benefit of the steam passing out of the IP tract when the appropriate R/V in the IP tract uncovers the port in the sideplate between the IP and LP tracts. The function of following R/V's in both IP and LP tracts is as described for the HP and IP tracts except that radial exhaust ports may be formed in the LP plate through which steam may pass on to a condenser.

Grooves may be machined on the sides of tract plates and/or sideplates to receive compressible seals.

A triple expansion rotary steam motor in accordance with this invention has herein been described, but a single tract steam motor is equally applicable whilst a multiple tract rotar steam prime mover will follow the same principe of construction and operation and is similarly covered by this invention.

As a rotary air motor or interna combustion engine, the outer body comprising the laminated assembly of plates is also stationary while the centre portion consists of a rotating rotor. In this case also, the tract peripheral surfaces are not in the form of eccentric circles but have profiles designed to obtain optimum benefit of air or gas expansion, and are offset in relation to the central axis.

The air or gas entry port may be in the expansion chamber of the relevant tract fed from a rotar sleeve valve, in which case the shaft of the machine rotates and drives the rotary sleeve valve. In a further embodiment of the design, the rotor rotates on a stationary hollow shaft and air or gas entry is via a curved duct or ducts in the rotor admitting air or gas from the stationary hollow shaft. The relevant ports in the hollow shaft and rotor are so positioned as to align at a point to give optimum entry and expansion of compressed air or gas. Figure 3 refers to the latter embodiment.

Air motors or internal combustion engines in accordance with this invention may have one or more tracts, and tracts may have one or more R/V's per tract, but for air motors or interna combustion engines, the prefered number of R/V's is two in each tract positioned in the rotor with pivot pins at an angular separation of 180 .

When designed as an optional air motor or interna combustion engine, this invention provides for the incorporation of injector and/or ignition equipment in the tract plate where expansion begins to take place.

The tract plates are designed to provide space and sufficient depth of material for the integral embodiment of expansion or combustion chamber and the fitment of one or more injector and/or ignition component located therein for optimum flame propagation.

The drawings which accompany this specification refer in Figure 1 to the function of this invention as a positive displacement pump in which the outerbody'1'consisting of the laminated assembly of tract plates'T', sideplates'S'and endplates'e'are held in compression by tension members, all of which rotate about a stationary core'C'.

Each tract plate'T'has curved radial intake ducts'a'formed in the advancing sector of the tract eccentric, and has two curved vanes'R/V'lying in it.

In this diagram of a three tract compressor, the other two tracts'T2'and'T3'are indicated by dotted line eccentric circles with R/V's not shown for reason of clarity.

Each tract plate has a conventional spring pressure seal'm'across the full width of the tract at the position of minimum eccentricity.

The R/V's have hinged tip members'r/t' and the complet R/V's are attached by their pivot pins'p'to a stationary core'c'.

The core consists of segments, one to each tract which are keyed onto the central hollow shaft'h'with woodruff keys'k'and are held together by threaded members'b'parallel to the shaft'h'.

Between the core segments and held in compression by threaded members'b' (Figure 1) are pairs of metal rings'g' (Figure 4) and nipped between them a flexible diaphragm'f', having tapered edges and of larger diameter than rings'g'.

The rings'g'are so positioned as to align with the sideplates's' (Figure 4) which have vee section grooves machined into their inner bore.

The tapered edge of the diaphragm'f'pro- jects into the vee section groove to provide inter-tract sealing.

The segments of the core'c'are fitted with valves'v'which allow the air in the diminishing space of tract'T'to pass into the bore of hollow shaft'h'.

The drawing in Figure 2 refers to the function of this invention as a triple expansion rotar steam motor.

The laminated outer body'1'consisting of tract plates'T', sideplates'S'and endplates 'e'held in compression by tension members 'n'is stationary in this function.

Long dowels'w', split longitudinally serve to locate tract plates and sideplates accurately in relation to one another.

Figure 2 shows a tangential steam entry port'in', formed in the HP tract plate T1 through which steam enters the HP tract.

Three R/V's each having a pivoting tip member'r/t'are attached by their pivot pins 'p'to rotor'r'which is carried on hollow shaft 'h'and bearings located in endplates'e'.

The sideplate between HP tract T1 and adjacent IP tract T2 terminates for the exposed depth of HP tract at optimum position for steam transfer being 140 as shown in Figure 2.

The R/V's in IP tract T2 are a number of degrees in advance of R/V's in HP tract so that when an R/V in HP tract T1 uncovers the termination of sideplate at 140 , transfer of steam from HP tract T1 to IP tract T2 takes place.

The sideplate between IP tract T2 and LP tract T3 terminates similarly but at 290 as shown in Figure 2.

Steam transfer then again occurs and the third expansion of steam takes place in LP tract T3 from whence it escapes radially via exhaust ducts'Ex'formed in the LP plate which in practice would incorporate a manifold passing the steam on to a condenser.

The drawing in Figure 3 refers to the function of this invention as a prime mover either in the form of an air motor or as an interna combustion engine. The R/V's with their hinged tips'r/t', lie in their tracts T being hinged on their pivot pins'p'and attached thereby to a rotor'r'which is carried on bearings located in endplates of laminated stationary body'1', held together by tension members'n'.

In this function the rotor rotates on a stationary hollow shaft'h', and compressed air or gas supplied to the end or ends of hollow shaft'h'passes via ports in stationary hollow shaft'h', and ducts'd'in rotating rotor'r' into the expansion or combustion chamber formed integrally with tract T.

An alternative method of air or gas entry is from a rotary sleeve valve lying across the plane of the tract or tracts through suitably shaped ports in the expansion chamber of the tract and is driven directly from the main shaft which in this adaptation rotates with the rotor.

Products of combustion or expanded air escape via ducts'Ex'formed radially in tract plate T.

Figure 4 shows a section A-B of Figure 1 with the axis thereof in a vertical position.

Claims (14)

CLAIMS Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I now claim is:

1. Rotary aspirating machines having, for prime mover function, stationary outer bodies with rotating inner rotors and for pumping function, rotating outer bodies with stationary inner cores. These machines, whether func tioning as prime movers or pumps, embodying a laminated principe of construction for outer bodies consisting of series of parallel tract plates, sideplates and endplates held together by tension members and in which tracts in the tract plates are the result of eccentric circles or other profile forms cut from the full width of tract plate and lying in which are curved vanes pivoted at one end and having pivoted tip members at the other end.

2. The principe of compressing air or other mixtures taken from the circumference of a circula body into the centre of that body, and in particular, rotary positive displacement pumps in accordance with claim 1 in which curved vanes are anchored by their pivot pins to a stationary core while the outer body, being an assembly of tract plates, sideplates and endplates, rotates about a central hollow shaft on which the core is mounted with the curved vanes lying in their tracts and rocking about their pivot pins during rotation of the pump body, segments of the core incorporating suitable valves for the effective passage of air into the hollow shaft, the rotational axis of such machines being vertical, horizontal, or in any other plane.

3. Rotary steam prime movers in accordance with claim 1 in which steam is admitted to one or more tracts either via a curved tangential duct in the stationary tract plate, or via a curved duct in the rotating rotor body from a stationary hollow shaft, and in which the sideplates between tracts incorporate ports designed to permit the transfer of steam from HP tract to IP tract and from IP tract to LP tract, and similarly for additional numbers of tracts according to the required capacity of an individual machine.

4. Rotary prime movers in accordance with claims 1 and 3 in which, to accomplis the helical passage of steam ascertained in claim 3, the rocking vanes (R/V's) in tracts adjacently subsequent to the initial steam entry tract are attached to the rotor in advance of rocking vanes (R/V's) in tracts from which the steam has passed.

5. Rotary prime movers in accordance with claim 1 in which the tract plate internal profile embodies a volumetrically limited space which may function as a combustion or expansion chamber in which a port may be formed for the intake of air or gas.

6. Rotary prime movers in accordance with claims 1 and 5 in which the tract plate incorporates threaded apertures within the width of the plate and within the space of the combustion or expansion chamber in which injection and/or ignition components may be fitted.

7. Rotary prime movers in accordance with claim 1 in which curved vanes lying in their tracts within a stationery outer body are attached to a rotating rotor by their pivot pins, the rotor being mounted on a hollow shaft and supported in bearings located in the end plates, and in which when functioning either as a rotary air motor or interna combustion prime mover, compressed air or gas is sup plied to one end of a rotary sleeve valve lying across and at right angles to the plane in which the relevant tract lies and adjacent to the expansion chamber of the tract, the sleeve valve being driven at the opposite end and directly from the main shaft of the machine.

8. Rotary positive displacement pumps in accordance with claims 1 and 2 but in which the outer body comprising the eccentric tract plate or plates is stationary, with air or gas intake and delivery ports and valves located therein at side positions of the tract, and in which the rotor carrying the R/V's rotates with tips leading and the R/V pivot pins trailing.

9. A type of construction in accordance with the preceeding claims in which tracts of rectangular cross section are formed by a laminated assembly consisting of parallel plates being tract plates, sideplates and end plates held in compression by tension mem- bers passing at right angles to and through the parallel plates and in which the peripheral inner surfaces of the tracts are the result of eccentric or other profile forms being cut from the full width of the relative tract plate.

10. A primary component according to and compatible with the preceeding claims which when oscillating within a tract of variable cubic capacity as rotation movement be tween core or rotor occurs, performs the func tion of a piston, and which consists of a rocking vane (R/V) curved in its length with straight and parallel sides with a pivotal eye at one end of major depth and tapering to a minor pivotal eye at the other end where a tip member also tapered in its length pivots about the minor eye and has a width equal to that of the R/V and tract, and which by virtue of its form and offset nature performs the function of a pressure operated seal between the R/V and the tract peripheral surface.

11. Rotary aspirating machines in accor dance with claims 1 and 2 in which the rotational axis consists of a hollow shaft either stationary or rotating according to function of the machine, and adapted to receive or deliver air, gas, steam or other working medium, and which may be connected to outer or other reservoirs or sources of supply.

12. Rotary aspirating machines in accor dance with claims 1,5 and 6 in which a rotor incorporating radial ducts, curved or straight, rotates about a central stationary hollow shaft which is supplie with compressed air or gas and which embodies ports so located as to align with the said radial ducts in such a manner as to effectively perform the function of a s) eeve va) ve mechanism.

13. Rotary aspirating machines in accor dance with the preceeding claims in which vee section grooves formed in the bore of sideplates or other plates compatible with this invention, rotate astride the tapered edge of a flexible diaphragm held stationary or vice versa so as to function effectively as an air seal between adjacent tracts.

14. The principe of using curved vanes in tracts of rectangular cross section as described and ascertained in this specification for the purpose of translating the work of natural elements such as air, steam, gas or other mixtures into useful mechanical work and in particular, the principes of compressing mixtures such as air or gas by means of eccentric tracts rotating contra to stationary curved vanes lying within them, and of rotating curved vanes in stationary tracts transmitting the pressures of expanding steam or gases into moments of force on rotors of the relevent machines.

CLAIMS (12 Dec) 1984 Rotary aspirating machines of the eccentric and pivoting vane type having, for prime mover function, stationary outer bodies with rotating inner rotors, and for pumping function, rotating outer bodies with stationary inner cores, in which latter function improved volumetric capacity is achieved by the location of intake ports in the advancing side of tract eccentric thus providing a steadily expanding volume for induction throughout each revolution inasmuch that the point of maximum tract eccentricity traces a circula orbit with same radius, giving an intake capacity of maximum tract cross-section multiplie by circumference of mean tract depth. Such machines embodying a laminated type of con struction consisting of series of parallel tract plates, sideplates and endplates compressed together by tension members and in which tracts are the result of eccentric circles or other profile forms cut from the full width of tract plate lying in which are curved vanes pivoted at one end and having pivoted tip members at the other end.