GB2043783A

GB2043783A - Rotary Positive-displacement Fluid-machines

Info

Publication number: GB2043783A
Application number: GB7943700A
Authority: GB
Original assignee: Jocottet SA Ets
Current assignee: Jocottet SA Ets
Priority date: 1979-01-04
Filing date: 1979-12-19
Publication date: 1980-10-08
Also published as: DE2941567A1; FR2445898A1

Abstract

An actuator comprises a stator (1) and a rotor (2) with blades (4) extending across chambers formed by fixed partitions (3), said blades being separate parts secured to the hub of the rotor. <IMAGE>

Description

SPECIFICATION Alternating Rotary Jack The invention relates to an alternating rotary jack, i.e. a hydraulic motor, fed by a fluid under pressure, to which an alternating movement with a limited amplitude is imparted, and providing an output torque.

The alternating movement with limited amplitude is obtained by means of a feed effected by a servo-valve alternately to two diametrically opposed chambers of a stator, while the rotor comprises two diametrically opposed blades, which are therefore housed respectively in said chambers which are defined by two diametrically opposite partitions forming part of the stator and bearing on the rotor to ensure the sealing.

Hitherto, the blades have been made integral with the rotor. This has required sophisticated machines for machining the parts of the rotor against which the partitions of the stator come to bear to ensure the sealing.

It is an object of the present invention to avoid the use of such sophisticated machines.

The present invention is an alternating rotary jack comprising a stator and a rotor housed in the stator, two communicating chambers formed by an internal partitioning connected to the stator and each containing a blade connected to the rotor, said blades being separate parts secured to the rotor.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a section perpendicular to the axis of rotation of a conventional motor; Fig. 2 is a section through the axis of rotation of the motor of Fig. 1; Fig. 3 is a section perpendicular to the axis of rotation of a motor according to the invention; and Figs. 4 to 1 3 illustrate the different stages of the machining of the motor illustrated in Fig. 3.

In Fig. 3, the two blades 4 are rigidly connected to the rotor 2 by any known technological means, for example by shrinking on, fitting cold or by screws, without this list being limiting.

The two fixed partitions 3 are fitted into the actual stator 1 and come into contact with the central portion of the rotor 2 in order to ensure the sealing.

The mode of sealing will not be described or illustrated, and may be ensured by any conventional means, either outside the blades or between the rotor and the blades. More particularly there is designated on Figs. 1 and 2: by 1 the stator, by 2 the rotor and more particularly the body of this, by 3 the fixed partitions rigidly connected to the body 1, by 4 the blades, by 5 and 5' the feed conduits which feed the chambers 6 and 7 alternately, the alternation being ensured by a servo-valve, not illustrated. Finally, there will be noted in Fig. 1, the drill-holes 8 and 8', one of which is in the plane of the Figure. They ensure the balancing of the pressures at each side of the axis of rotation.

Referring to Fig. 3, for which the same reference numerals are used, the blades 4 are clearly seen which constitute independent parts fitted to the rotor. As has been stated, these parts are rigidly connected to the rotors by any known technological means.

Another difference is the locality of the drillholes 8 of the rotor, disposed parallel to one another, in a plane of symmetry.

Finally, it will be noted that this form of embodiment, contrary to the solution in the public domain, permits any method for the regulation of the contact between the fixed blades and the rotor.

So far as the sealing is concerned, it does not appear necessary to describe it; this can be ensured by any conventional means of the public domain either outside the blades or between the rotor and the blades.

The machining process permitted by the invention is as follows: Rotor: the machining of the rotor is carried out in accordance with the indications of Figs. 4 and 5, to the appropriate dimensions and tolerances.

Fig. 4 is a view from above, Fig. 5 is a section perpendicular to the axis of rotation.

Fig. 4 is a view from above in which 10 is the drive shaft of the motor and 1 2 the parts which rotate in the body of the motor.

The drill-holes which ensure the communication between the opposite chambers are indicated at 8 and 8'.

In Fig. 6, the seatings provided for the feet of the blades are designated by 12.

These two figures therefore indicate by X the useful dimension to be machined and by Y the depth of the seatings of the feet of the blades.

Blades: the machining of the two blades is carried out in accordance with the indications of Figs. 6 and 7, the dimensions A' and D' of the blades corresponding to the dimensions A and D of the rotor. Then the fitting of the two blades is effected in the two seatings provided for this purpose in the rotor.

Partitions: the machining of the two partitions is carried out in accordance with Figs. 8 and 9, the B', D' and the dimension C' corresponding to the same dimensions B, C, D of Fig. 4 concerning the rotor.

Body: the machining of the body (Figs. 10, 1 1 ) in a parallelepiped or circular block with a bore D' corresponding to the Q)D of the rotor of Fig. 4 and two bores E' corresponding to the Q)E of the blades and partitions of Figs. 9 and 8.

Assembly: the fitting of the rotor 2 in the body 1, Figs. 12, 13. The placing in position of the two partitions and the fixing of these to the body 1 is effected by any conventional means.

The motor is then assembled.

By comparing Fig. 3 of the motor according to the invention and Fig. 1, (a motor in the public domain), the following remarks may be made in favour of the former: 1-absence of bearings the rotor serves as a bearing by turning in the bore of the body.

2-absence of axial stress on the bearings, due to the hydraulic pressure.

3-absolute machinability on conventional machine (lathe, milling machine, boring machine).

Claims

1. An alternating rotary jack comprising a stator and a rotor housed in the stator, two communicating chambers formed by an internal partitioning connected to the stator and each containing a blade connected to the rotor, said blades being separate parts secured to the rotor.

2. A jack as claimed in claim 1, in which the communication between the two chambers is provided by drill-holes in the rotor, which extend into the blades.

3. A jack as claimed in claim 1 or claim 2, in which the rotors serve as bearings and turn in corresponding bores formed in the body of the stator.

4. A jack as claimed in any preceding claim, in which fluid pressures in the chambers are so balanced as to avoid any axial stress on the bearings.

5. A jack as claimed in any preceding claim, in which the partitions are externally accessible for the regulation of their pressure on the rotor,

6. A method of manufacturing a jack as claimed in any preceding claim, in which the machining of the rotors and of the blades precedes the fitting of the blades in the rotor.

7. A method as claimed in claim 6, in which the machining of a body in a parallelepiped or circular block precedes the fitting of the rotor in the body and the placing in position of the partitions, as well as the fixing of these to the body by any suitable means.

8. An alternating rotary jack substantially as hereinbefore described with reference to, and as shown in, Figs. 3 to 13 of the accompanying drawings.

9. A method of manufacturing an alternating rotary jack substantially as hereinbefore described with reference to Figs. 4 to 1 3 of the accompanying drawings.