DE1010790B - Axial seal - Google Patents

Description

GERMAN

The invention relates to an axial seal between structural elements rotating relative to one another with a slip ring, which is guided in one construction element and from which to be sealed pressure is pressed against the other structural element.

Axial seals of known type can have a slip ring and a guide part between which a chamber is formed in which a sealing ring is located. This sealing ring represents the sealing limit between two rooms to be sealed against each other.

You can use another known construction for the pressing of the slip ring essentially use the pressure of a medium to be sealed, with an axial spring being provided, which at Standstill of the machine can press the corresponding parts against each other or for a relatively has to provide a low constant overpressure. Sealing arrangements of this known However, Art cannot be used for any print ratio between the two sides will.

When sealing between a shaft and the housing of a component surrounding the shaft Devices known that should allow a seal regardless of which side the higher pressure prevails.

With facilities of this type, special precautions are required to prevent any occurring Operating requirements to ensure a sufficiently reliable seal.

The invention aims at a seal between the surfaces of two relatively circumferential Construction elements that have a simple structure and always reliably seal, especially when when the direction of pressure on the sealing device is reversed.

According to the invention, there is an axial seal between structural elements that rotate relative to one another provided, which has a slip ring which is guided in the one construction element is and is pressed against the other structural element by the pressure to be sealed, and at between the slip ring and the guide part of a construction element with a chamber a round rubber ring is arranged, which through channels with under different, reversible pressure standing rooms is in communication, the chamber being arranged between the rooms, that in each case the pressure prevailing in the space with the greater pressure and on the end faces acts and presses the slip ring against the other construction element, is higher than the pressure.

Axial seal

Applicant:
Cambi Idraulici Badalini S. p. A., Rome

Representative: Dipl.-Ing. W. Cohausz, patent attorney,
Düsseldorf, Schumannstr. 97

Claimed priority:
Italy March 8, 1954

Giovanni Badalini, Rome,
has been named as the inventor

which acts on the surface of the slip ring and wants to lift it off the construction element.

The invention is described in more detail with reference to the drawings.

Fig. 1 shows to explain the problem of the invention a longitudinal section through a sealing device of known type;

Fig. 2 shows in longitudinal section a preferred embodiment of the axial seal according to the invention.

In Fig. 1, which shows a known embodiment of a rotary seal acted upon on one side, two chambers 6 and 7 are shown, in which different pressures prevail. Chambers 6 and 7 are bounded on the sides by surfaces 8 and 9, one of which is fixed, while the other is rotates, or between which a mutual rotation is possible. The seal between the two Surfaces is caused by a sliding ring 1, which is supported by an annular counter bearing 2 of the surface 9 is held.

The sliding ring 1 is pressed by the pressure against the surface 8 to by its adhesion to the Surface 8 to form a seal for the liquid, which due to the pressure difference between wants to flow from one chamber into the other in both chambers.

If z. B. in the chamber 7 there is an overpressure, the diameter D _{2 of} the sliding ring 1 with respect to the diameter D ₃ and D _{1 of} this ring must be chosen so that the force due to the liquid pressure on the annular surface 12 between the Circles with the diameters D ₂ and D ₁ acts on the ring, is greater than the force that is exerted on the ring by the gradually decreasing fluid pressure from the inside to the outside.

709-549/223

Förtnige surface 13 is exerted between the circles with the diameters P ₃ and D ₁ , which acts in the opposite direction and tends to lift the ring 1 from the surface 8.

The diameters D ₁ and D _{3 of} the slide ring shown in FIG. 1 for the case that overpressure prevails in chamber 7 are dimensioned so that there is no longer a seal when there is overpressure in chamber 6 with respect to chamber 7; the force generated by the pressure on the annular surface 14 between the circles with the diameters D ₃ and D ₂ is less than the force exerted by the decreasing, from the outside inwards acting pressure acting in the opposite direction on the annular surface 13 acts, which is limited by the circles with the diameters D ₃ and D ₁ , so that a lifting of the sliding ring 1 from the surface 8 is effected.

In Fig. 2, a preferred embodiment of the seal according to the invention is shown in which the Sliding ring 1 and the annular counter bearing 2 have such a shape that an inner recess 11 which is connected to the chamber 6 by conduits 4; there is also an inner recess 10, which adjoins the recess 11 and is connected to the chamber 7 by lines 5 connected is. The annular recesses 10 and 11 are separated by an annular seal 3, the consists in a known manner of a material that in the presence of the liquid in the Chambers 6 and 7 can work.

Instead of the lines 4 and 5, suitable cutouts can be made between the contact surfaces of the ring 1 and the counter bearing 2 can be provided, which establish the connection.

If the pressure in chamber 7 is higher than that in chamber 6, the liquid enters chamber 10 through lines 5 and presses sealing ring 3 against lines 4. This creates a seal between sliding ring 1 and counter bearing 2. At the same time, the pressure prevailing in chamber 7 is also established in chamber 10, so that a force is exerted on the annular surfaces 15, 16 between the circles with the diameters D ₀ and D _{i of} the ring 1. Since this force is greater than the force that acts due to the decreasing pressure on the annular surface 13 of the ring 1 between the circles with the diameters D ₁ and D ₄ , and tends to lift the ring 1 from the surface 8, causes the the former force that the ring 1 rests firmly on the surface 8 and seals effectively.

If, on the other hand, there is an overpressure in the chamber 6 with respect to the chamber 7, the liquid enters the chamber 11 through the lines 4 and the seal 3 is pressed against the lines 5 in such a way that the liquid is prevented from flowing through. In this case, the pressure of chamber 6 also prevails in chamber 11, so that a force is exerted on the annular surfaces 14, 15 of the ring 1 between the circles with the diameters D ₁ and D ₃ ; this force is greater than the force acting in the opposite direction of the decreasing pressure on the annular surface 13 between the diameters D ₁ and D ₁ .

The invention advantageously enables the formation of a seal with the aid of a sliding ring, which is generated solely by the fluid pressure without the use of special auxiliary equipment, z. B. od springs. Like. Is held. As mentioned. are the vertical parts of the sliding ring 1 and the with it cooperating element 2 dimensioned so that the greater fluid pressure a force generated, which presses the sliding ring 1 against the surface 8 and which is larger than that due to the difference the pressures in the spaces 6 and 7 occurring force that the contact surface 13 of the sliding ring 1 of the Area 8 tries to take off.

The seal according to the invention can therefore also be used to advantage in particular when the location the greater pressure, i.e. the direction of pressure, changes. By the measures according to the invention are formed in the sliding ring 1 surfaces, one of which is always from the pressure in the chamber 7 and one other is always acted upon by the pressure in the chamber 8, while the third radial surface is always from the Pressure is applied which is greater.

The invention has the particular advantages that as a pressure medium for pressing the seal the already existing fluid pressure is used, so that springs or similar auxiliary devices are superfluous. This significantly reduces wear and tear. When the pressure of the liquid to be sealed is used as the pressure generator, the pressure is also generated only be as large as necessary between the sealing surfaces. This is additional the wear is significantly reduced.

Claims (1)

Claim Axial seal between relatively rotating construction elements with a Slip ring that is guided in one structural element and of the one to be sealed Pressure is pressed against the other structural element, characterized in that between the slip ring (1) and the guide part (2) of one construction element (9) a Chamber (10, 11) with a round rubber ring (3) is arranged through channels (4, 5) with under different, reversible pressure standing spaces (6, 7) is in communication, the Chamber (10, 11) is arranged between the spaces (6,7) in such a way that in each case the pressure which prevails in the room with the greater pressure and is applied to the end faces (14, 15 or 15, 16) acts and presses the slip ring (1) against the other structural element (8), is higher than the pressure that acts on the surface (13) of the slip ring (1) and this from the Construction element (8) wants to take off. Considered publications:
U.S. Patent No. 2,672,357;
British Patent Nos. 632 957, 671 165;
French patents nos. 983 992, 1 034 254. 1 sheet of drawings © 709 54ft'223 6.57