The invention relates to vane machine where part of the cylinder is stationary while other cylinder parts rotate.
The vane machine may be a working machine (engine) for continuous converting of fluid energy into mechanical power or a driving machine (pump) for continuous raising, forcing, compressing, or exhausting of fluid by mechanical power or other means, from the volumetric rotating machine group, utilising compressible or incompressible fluids as the working media.
In the International Patent Classification, it is classified as the Field F—Mechanical engineering; Class F 01—Machines or engines in general; Subclass F 01 C—Rotary piston machines or engines; Group 13/00—Adaptations of machines or engines for special use, combinations of engines and devices driven thereby; Subgroup 13/02—for driving hand-held tools or the like; and 13/04—for driving pumps or compressors.
The greatest problem present with volume machines, especially with vane volumetric machines, are the volumetric and the mechanic losses. Volume losses result from the insufficiently large openings letting the working media in and out of the working chamber of the machine. Volumetric losses also appear due to leakage of the fluid from higher-pressure space of the working chambers into lower-pressure space of the working chambers. Mechanic losses result from friction between the machine's mutually contacting rotating and stationary parts that make parts of the working chamber.
Consequence of the higher volumetric and mechanical losses is the lower volumetric and mechanical effectiveness of the machine, that is, its low total effectiveness.
The technical problem solved by the invention is an enhanced charging and discharging of the working chamber with the working media, also decrease of wear of the vane surfaces in contact with the cylinder axial and radial surfaces, and enhanced sealing of vanes against the cylinder axial and radial surfaces.
In vane machines, the vanes are pressed against the cylinder walls in the working chamber by the centrifugal force, in some embodiments additionally by springs or providing the vane inner radial surface with the working-media pressure.
Wear of the stationary-cylinder vane machines is proportionate to the total force pushing the vane against the cylinder surface in the working chamber and to the friction coefficient. The friction problem is being solved, among others, by selection of materials of which the vanes and the cylinder are made. The vanes may be axially moved, wherefore they lean against the working chamber stationary lateral surfaces. Due to the relative high velocities between the vane lateral surface and the working-chamber lateral surfaces, ware is present in both surfaces in contact, that is, the mechanical efficiency of the machine is deteriorated. In this embodiment, the working chamber may be charged and discharged radially, which is favourable with regard to the volumetric efficiency.
In another vane-machine embodiment, the cylinder rotates, wherefore the relative velocities at the contact between the cylinder surface, which rotates in the chamber, and the vane is decreased, this again resulting in decrease of wear, which is favourable with regard to the mechanic efficiency. The setback of this embodiment are the working-media axial intake and exhaust, unfavourably effecting charging and discharging of the chamber, thus worsening the volumetric efficiency.
Similar to the first embodiment, the vanes may be axially moved, wherefore they lean against the chamber stationary lateral surfaces. Due to the relatively large velocities between the vane lateral surface and the working-chamber lateral surfaces, wear is present in both surfaces in contact.
The state of the art is defined by two patent documents, that solve the known technical problems only partially.
JP 08 18987 A—offers solution of the problem of wearing of cylinder parts.
U.S. Pat. No. 3,437,079 A—solves mechanical losses at cylinder and working chamber lateral surfaces and the losses from leakage on cylinder. It has vanes with axial grooves on upper side of the vane body.
The essence of the invention is machine that has stationary and rotating cylinder parts.
In the stationary cylinder part there are radial openings allowing the working media to pass through in and out of the cylinder working chamber.
The cylinder rotating parts are roller or sliding bearings, firmly inserted in the cylinder stationary part. Bearing inner rings, or additional rings, firmly inserted in the bearing inner rings, are actuated by the vanes to rotate.
Lateral plates, closing the cylinder working chamber are firmly pulled over the rotor and rotate with it.
The vanes with axial and radial grooves are inserted in rotor, enhancing sealing of working media between the vanes and other parts in contact. Sealing is of the labyrinth type.
The invention description relates to the vane-machine basic version, the cylinder of which consists of one stationary and two rotating parts.
More complex versions of the vane machine may consist of several stationary and rotating cylinder parts, where all combinations of layouts and sizes, depending on the required technical characteristics, are possible.
The basic vane-machine embodiment, as shown in the
Cylinder Stationary Part A
The cylinder stationary part A is shown in the
The cylinder stationary part A is shaped as a hollow roller, in the centre of its hollow part having the inner shroud 1 with the working surface 2 and the lateral surfaces 3. Within the shroud rotates the rotor C.
At the intake and the exhaust, the cylinder stationary part has the openings 4, for the covers D.
In the shroud 1 there is the opening 5, allows the working media to pass through in, and the opening 6, allows the working media to pass through out of the cylinder working chamber. Openings 5 and 6 are rectangular and radial relative to the cylinder. Openings 5 and 6 may be of other shapes as well.
Cylinder Rotating Parts B
The cylinder rotating parts B may be designed in one of the following two variants:
variant 1—without additional rings;
variant 2—with additional rings.
The cylinder rotating parts B, in the variants 1 and 2, may be roller or sliding bearings.
Rotor C
As shown in the
The rotor may have one or several vanes.
Slots in the rotor body may also be designed to enable the vanes to move under an angle formed by the vane surface and the rotor radial direction.
As shown in the
Covers D
As shown in the
Vanes F
The vanes may be made with or without grooves. This invention description relates to a vane machine having vanes with grooves in its rotor (labyrinth sealing).
The vanes F,
As the rotor rotates, the vane flat parts 23 actuate the inner rings 8 or the inner rings 10 respectively, of the cylinder rotating part.
Functioning of the Invention
Views of a closed and assembled vane machine are shown in the FIGS. 1—front, 2—side, 3—back, and 4—cross-section X-X.
The vane-machine working chamber 16,
The vane machine works by the principle of creating the tangential force, resulting from the pressure difference at the rotor vanes. The tangential force at the rotor shaft appears as the torque momentum that, besides the working number of revolutions of the machine, generates the engine power. As with driving machines (engines), the machine power transforms into the mechanic work available, whereas as working machines (pump) the available power is used to change the working fluid pressure with a given flow.
The vane machine with cylinder stationary and rotating parts is powered by bringing the media through the opening 5 into the cylinder working chamber 16. In this process the working media, due to the pressure difference, makes the rotor to rotate. Media in the space between two vanes leaves the cylinder working chamber 6 through the media exhaust opening at the opposite side of the cylinder, and the cycle repeats.
Rotation of the rotor creates a centrifugal force that pushes the vanes F out of the slots 13, this creating friction between the vane flat parts 23 and the working surface 9 of the bearing inner rings 8 or the additional ring 10, and them (putting inner rings 8 or the additional rings 10) in motion.
The velocities of sliding of contact surfaces of the vanes and the bearing inner rings or the additional rings firmly inserted in them, makes the difference between the momentary peripheral velocities of the vane outer edge and the momentary peripheral speed due to the inner ring rotation. In this machine, the said velocities depends on the number of vanes. For only one vane in the rotor the relative velocities is zero, whereas for several vanes the maximum sliding velocities equals the mean speed resulting from the difference of the vane velocities of the maximum and minimum peripheral velocities relative to the current bearing inner-ring rotation velocities. The role of the cylinder rotating part with the bearing rings is to decrease the sliding velocities, thereby to decrease the friction, noise and wear rate, which all increase the vane-machine's mechanical efficiency.
The vanes are axially movable, leaning against the plates 14 of the rotor C. The plates are firmly connected to the rotor and, therefore, rotate with it. This way it is achieved the minimum relative velocities of sliding between the vane lateral edges and the plates, this again resulting in decrease of the rate of friction wear and increase of mechanical efficiency. The relative velocities between the vane lateral edges and the working-chamber plates results from the vane radial motion. Between the vanes and the cylinder stationary part, or the working surface 2 of the shroud 1, there is a clearance wherefore there is no mutual contact, which avoids friction wear at this region.
Such vane-machine embodiment enables the working media intake opening 5 and the exhaust opening 6 to be positioned radially, whereby, and due to their size, shape and position, better charging and discharging of the working chamber is achieved (volume efficiency), which is among major setbacks of the presently known vane-machine embodiments.
The relative speed between the rotating inner rings, or the bearing additional rings, and the vanes is significantly decreased, wherefore the vane friction wear is decreased.
Pressure of the vanes against the rotating inner rings, or the bearing additional rings, creates sealing at this region. The pressure may, if necessary, be additionally increased by a spring placed in the vane slot or by providing the vane inner radial surface with the working media of higher pressure, which results in an additional radial force.
Rotation of the rotor creates conditions for periodical charging and discharging of the working chamber, wherefore, depending on the vane-machine purpose, the working-chamber pressure, from intake to exhaust, is increased or decreased.
The vane machine with cylinder stationary and rotating parts decreases ware of the vane contact surfaces in contact with the cylinder axial and radial walls in the vane-machine working chamber, enhances charging and discharging of the working chamber with the working media, and solves the issue of sealing between the vanes and the cylinder inner stationary part and the rotor lateral plates. This enhances the volumetric efficiency of the machine and decreases losses resulting from friction between the contact surfaces, wherefore the mechanical efficiency of the machine is increased.
The work of a vane machine with cylinder stationary and rotating parts, for one rotor revolution, is the algebraic sum of the works of charging, expansion and discharge. The process may be described simply in a closed working cycle with compressible working media. The working chamber charging is isobaric, change of the state from a to b. The expansion process is the change of the working chamber volume from b to c. The working media discharge consists of three stages. The first stage is a sudden expansion from c to c′, when the exhaust canals start opening. The second stage of exhaust from c′ to d is discharge caused by the working volume decrease. The third stage, from d to a′, is compression of the residual working media in the working chamber after closing of the exhaust canals. The last stage of the cycles is charging the working chamber with new working media, wherefore the isochoric pressure suddenly rises from a′ to a.
The following equation shows the process and results from the energy equilibrium:
EdQ+dZ
M
=dU+dL+dZ
V
where:
The last two energy quantities may be determined with the following equations:
dZM=PMdGM and dZV=PVdGV,
where:
The primary problem of the vane-machine total efficiency is the volumetric efficiency, resulting from charging and discharging the working media in and from the working chamber (processes a′-a and c-c′-d-a′ in the p-v diagram). The volumetric efficiency problem is solved in this invention by the possibility of maximum utilisation of the stationary part of the working-chamber cylindrical wall for the working-media radial intake and exhaust canals. The structural design enables additional increase of cross-sections of the working-media intake and exhaust canals, since vane does not touch the canals, wherefore the canals may be designed as rectangular openings, which design reaches their largest possible area, which improves conditions of charging and discharging of the vane-machine working chamber.
Another important problem solved by the invention is wearing of the vanes, the rotating bearing inner or additional rings, and the rotating rotor plates. Introduction of roller or sliding bearings, the inner rings of which may be firmly inserted additional rings of adequate sliding properties, against which the vanes lean, decreases the relative speed of sliding at the sliding contact points, thereby their wear as well.
The vanes may be axially moved, wherefore they lean against the rotor lateral plates. In the existing vane-machine embodiments, the cylinder working chamber lateral plates are stationary, wherefore the resulting high velocities between the vane lateral edge and the lateral plates cause wear of both surfaces in contact. Introduction of lateral rotating plates at the rotor, that close the working chamber, decreases the relative velocities related to the vanes, wherefore the lateral wear caused by friction of vanes and plates is decreased. The relative velocities between the vane lateral edges and the working chamber plates results from the radial motion of the vane only. Decrease of the friction losses improves the machine's mechanical efficiency.
Presentation of Vane Machine With Several Stationary and Rotating Cylinder Parts
The cylinder stationary and rotating parts may, besides the above decsribed basic vane-machine version, be distributed in several other ways, depending on the given technical characteristics of the machine.
In the embodiments presented, the lateral plates 14, rotating together with the rotor C, are placed in eccentric openings in covers D, whereas between the lateral plates 14 and the bearings 15, in which the rotor rotates, there are inserted rings 15′.
In vane machines with several stationary cylinder parts, in each of them are made rectangular openings letting the working fluid in (5) and out (6) of the working chamber 16 of the cylinder, Gigures 31a) and b), or are made with working fluid intakes and exhausts through the vane-machine casing,
The additional rings 10 on rotating parts of the cylinder B can be wider than the inner ring 8,
The above mentioned complex vane-machine versions do not change the spirit of the invention as presented in the basic version of the vane-machine with stationary and rotating cylinder parts.
The vane machine with cylinder stationary and rotating parts may be applied in industry as driving or working machine. When used as a working machine, the imported mechanical work, with a given flow, is transformed into change of pressure of compressible or uncompressible working fluid, and when used as a driving machine, it transforms the primary available pressure of compressible or uncompressible working fluid into mechanical work.
As a working or driving machine with compressible fluid, it is used as: pneumatic tool, in mechanisation of various technological processes, as large Diesel engine starter, compressor, vacuum pump, internal-combustion engine.
As a working or driving machine with uncompressible fluid, it is used with: force, movement and momentum transmission systems in building machines, hydraulic cranes, ship hydraulic systems, machine hydro-drive, and with control, regulation or protection in hydraulic systems aimed to automation of working processes.
As a pump or a hydro-engine, it has two fields of application—with regard to the working fluid. When the working fluid is mineral oil, self-lubrication decreases friction and, therefore, wear of the vanes and the casing, which makes the vane-machine greatest setback. This is applied with force, movement and momentum transmission systems in building machines, hydraulic cranes, ship hydraulic systems, machine hydro-drive, and with control, regulation or protection in hydraulic systems aimed to automation of working processes. Hydraulic vane machines have a wide range of rotation speed. Small inertial forces of its rotating parts often make starting and stopping of the machine easier. When applied with non-lubricant working media, the issue of vane and casing wear remains the main hindrance in vane machines or pumps.
Letters and numbers used in the invention description have the following meanings:
A—Stationary Part of the Cylinder
B—Rotating Parts of the Cylinder
C—Rotor
D—Cover
F—Vanes With Grooves
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/HR2006/000002 | 3/6/2006 | WO | 00 | 8/29/2008 |