EP1503034A1

EP1503034A1 - Gerotor type machine

Info

Publication number: EP1503034A1
Application number: EP03725936A
Authority: EP
Inventors: Vladimir Vsevolodovich Davydov
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-04-24
Filing date: 2003-04-22
Publication date: 2005-02-02
Anticipated expiration: 2023-04-22
Also published as: RU2214513C1; WO2003091543A1; AU2003231438A1; ATE522700T1; EP1503034A4; EP1503034B1

Abstract

The invention relates to hydro and pneumatic engineering and can be used as a pump, a compressor or a motor.

The inventive gerotor type machine for displacing liquids and gases along the longitudinal axis thereof comprises a stator, a screw rotor and a shell. The rotor is arranged in the shell in such a way that working chambers are formed between the mating surfaces thereof.

The shell is disposed inside the stator in such a way that it is rotatable and that working chambers are formed between the mating surfaces thereof. The passage area between the rotor and shell and between the shell and stator is embodied in such a way that it is variable along the longitudinal axis of the machine. Said rotor and shell are embodied in such a way that they are displaceable by an axial force for tightening the rotor, shell and stator to each other, thereby automatically taking up clearances when they are formed.

The inventive gerotor type machine makes it possible to automatically compensate the clearances formed between the rotor and shell, and between the shell and stator.

Description

Technical field

Background of the invention

Patent SU, A1, 909305 protects a gerotor machine, comprising a ring stator with contactors, a rotor with displacers, coaxially-mounted with respect to the stator with the formation of working chambers between their matingsurfaces; end surfaces of the rotor and the stator are provided with ring grooves and collars with matingsurfaces, and every working chamber is performed in the form of two profiled grooves, located at one of the matingsurfaces on both sides of collar in one angular sector.

A disadvantage of said device is its low efficiency as a result of small capacity of working chambers.

Patent SU, A1, 1237092 protects a gerotor machine, comprising a frame-mounted stator, performed with constant or alternating thread pitch and epicycloidal in cross-section, a spindle located in the stator with outer screw vaulted cross-section surface, having a thread pitch different from the inner screw surface of the stator, stator's inner screw surface and spindle's outer screw surface are mounted with the possibility of locking with or without clearance; the device is provided with a gear unit mounted between the stator and the spindle, spindle's vaulted cross-section is performed with the thread pitch one-unit bigger than stator's thread pitch, spinder's thread pitch is divisible by stator's thread pitch, and the gear unit is performed with transmission ratio equal to the ratio of stator's and spindle's pitches.

A disadvantage of said device is a huge constructive complexity and, as a consequence, low reliability.

A more simple and reliable is a gerotor type machine for displacing liquids and gases along the longitudinal axis thereof comprises a stator, a screw rotor and a shell. The rotor is arranged in the shell in such a way that working chambers are formed between the mating surfaces thereof. The shell is disposed inside the stator in such a way that it is rotatable and that working chambers are formed between the mating surfaces thereof. The passage area between the rotor and shell and between the shell and stator is embodied in such a way that it is variable along the longitudinal axis of the machine. Said rotor and shell are embodied in such a way that they are displaceable by an axial force for tightening the rotor, shell and stator to each other, thereby automatically taking up clearances when they are formed (US, A, 2085115).

This engineering solution is taken as prototype of the present invention.

The elements of the machine - rotor, shell and stator - always deteriorate during operation and clearances are formed between them, which stipulates partial loss of compression. These clearances can not be compensated in the process of machine's operation since the possibility of axial displacement of the rotor with respect to the shell and the shell with respect to the stator is absent. There are stops serving for the perception of axial force which is a consequence of excess pressure in the discharge pipe, which excludes the possibility of axial displacement of the rotor and the shell and depression in the suction pipe (bearing).

In order to remove clearances between the machine elements and, respectively, to restore the compression, the machine shall be disassembled and worn-out elements or their elastic covers shall be changed, which is a rather labour-intensive process.

Summary of the invention

The aim of the said invention is to develop a gerotor machine which makes it possible to automatically compensate the clearances formed between the rotor and shell, and between the shell and stator.

According to the invention, the inventive gerotor type machine for displacing liquids and gases along the longitudinal axis thereof comprising a stator, a screw rotor and a shell, the rotor being arranged in the shell in such a way that working chambers are formed between the mating surfaces thereof, and the shell being disposed inside the stator in such a way that it is rotatable and that working chambers are formed between the mating surfaces thereof, the passage area between the rotor and shell and between the shell and stator being embodied in such a way that it is variable along the longitudinal axis of the machine, wherein said rotor and shell are embodied in such a way that they are displaceable by an axial force for tightening the rotor, shell and stator to each other, thereby automatically taking up clearances when they are formed.

The applicant hasn't found any sources of information containing data on engineering solutions, identical to the claimed. In applicant's opinion, that enables to conclude that the invention conforms to the criterion "novelty" (N).

A direct technical result which may be obtained when realizing substantial features of the claimed invention is the fact that the clearances formed on account of rotor, shell and stator deterioration are automatically removed, as under the effect of axial force the said machine elements are displaced and tightly compressed one to another. No stops for the perception of axial force exerting effect upon the rotor and the shell are required, as the rotor rests upon the shell, and the shell - upon the stator. As a result of the automatic removal of clearances, the reduction of compression of the gerotor machine is prevented and the necessity of frequent disassembly and assembly of the machine when its components deteriorate is eliminated.

The applicant hasn't found any data on the influence of distinguishing features of the invention on the achievable technical result. The mentioned condition enables to conclude that the claimed engineering solution conforms to the criterion "inventive step" (IS).

Brief description of drawings

Hereinafter the invention is illustrated by detailed description of its embodiment with references to drawings as follows:

Fig.1 - gerotor machine, longitudinal section;

Fig.2 - section I-I in fig.1;

Fig.3 - section II-II in fig.1;

Fig.4 - section III-III in fig.1.

Preferred embodiment

The gerotor machine comprises screw rotor 1 and shell 2. Rotor 1 is located in shell 2 in such a way that working chambers 3 are formed between their mating surfaces, the passage area between rotor 1 and shell 2 is variable along the longitudinal axis of the machine; roller 4 is connected with rotor 1; shell 2 is disposed in such a way that it can be rotated inside stator 5.

In section I-I in fig.1, given in fig.2, total passage area S_Ipo between the rotor and the shell consists of the sum of passage areas a₁, b₁, c₁ of working chambers 3: S_Ipo= a₁+ b₁+ c₁. Total passage area S_Ioc between the shell and the stator consists of the sum of passage areas ℓ₁, f₁, g₁, h₁ of working chambers 6, formed between the matingsurfaces of shell 2 and stator 5: S_Ioc= ℓ₁+ f₁+ g₁+ h₁.

In section II-II in fig.1 (fig.3) total area S_IIpo= a₂+ b₂+ c₂, and total area S_IIoc= ℓ₂+ f₂+ g₂+ h₂.

In section III-III in fig.1 (fig.4) total area S_IIIpo= a₃+ b₃+ c₃, and total area S_IIIoc= ℓ₃+ f₃+ g₃+ h₃.

Drawings in fig.2, 3, 4 distinctly show that S_Ipo> S_IIpo> S_IIIpo, and S_Ioc > S_IIoc > S_IIIoc, i.e. that the passage area between the rotor and the shell changes along the longitudinal axis of the machine (decreases in the given example); the passage area between the shell and the stator changes, too.

The gerotor machine comprises suction pipe 7 and discharge pipe 8. Lower end of the rotor is provided with axis 9, located in bearing 10. Roller 4 is located in bearing 11. Roller 4 is fixed into blind hole 12; torque is transferred by means of dowel 13. Axis 9 can slide relative to bearing 10 within clearance 14.

In the given example the machine is used as a pump, but can be used also to transfer gas. The machine can also be operated in hydro- or pneumomotor mode.

The device works as follows.

The liquid enters into suction pipe 7 and then, under the rotation of rotor 1 and shell 2, enters into discharge pipe 8 through

working chambers

3 and 6. When the rubbing elements (rotor, shell, stator) deteriorate, the rotor and the shell are displaced along the machine longitudinal axis in the direction of the suction pipe as a result of axial force effect, the clearance between them is taken up and they are tightened to one another thereof, which prevents from the decrease of compression of the gerotor machine.

Industrial applicability

Common equipment and inexpensive materials are used for the production of the machine, which stipulates that the invention corresponds to the criterion "Industrial applicability" (IA).

Claims

Gerotor type machine for displacing liquids and gases along the longitudinal axis thereof comprising a stator, a screw rotor and a shell, the rotor being arranged in the shell in such a way that working chambers are formed between the mating surfaces thereof, and the shell being disposed inside the stator in such a way that it is rotatable and that working chambers are formed between the mating surfaces thereof, the passage area between the rotor and shell and between the shell and stator being embodied in such a way that it is variable along the longitudinal axis of the machine, wherein said rotor and shell are embodied in such a way that they are displaceable by an axial force for tightening the rotor, shell and stator to each other, thereby automatically taking up clearances when they are formed.