GB1589269A

GB1589269A - Rotary face seal

Info

Publication number: GB1589269A
Application number: GB3051176A
Authority: GB
Original assignee: WOODVILLE RUBBER CO Ltd
Current assignee: WOODVILLE RUBBER CO Ltd
Priority date: 1976-07-22
Filing date: 1976-07-22
Publication date: 1981-05-07
Also published as: ES230083Y; ES230083U; JPS5313052A; FR2359336A1; IT1092254B; DE2732658A1; NL7708138A

Description

(54) ROTARY FACE SEAL (71) We, WOODVILLE RUBBER COM PANY LIMITED, a British Company, of Rosson-Wye, Herefordshire, HR9 5NF, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : This invention relates to face seal assemblies which allow relative rotation between a shaft and another part such as housing, bearing or shaft collar, but which prevent escape of fluid between the parts.

Face seal assemblies are known which for their operation make use of a face seal component which bears resiliently against a counterface component adapted to be secured to a portion of the shaft and an annular seal which engages the housing or other part.

It is an object of the invention to provide a face seal assembly which can be handled as a complete unit prior to and during installation on the shaft.

In accordance with the present invention there is provided a rotary shaft seal assembly for providing a seal between a shaft and a housing or other part rotatable relative to the shaft comprising an annular seal for engaging one of the relatively rotatable parts and shaped to form an extension whose end surface is sealed to a face seal component, a counterface component engaging the face seal component, resilient means urging the annular seal and the end surface of the extension apart, and a retaining means lying adjacent the shaft and engaging the counterface component and being operatively connected to the end of the resilient means remote from the counterface component; the retaining means holding the face seal component to the counterface component to form an assembly which can be installed as a single unit and adapted to be compressed when mounted on the shaft so that it forms a fluid-tight seal between the shaft and the counterface component.

More specifically the present invention may take the form of a fluid face seal assembly comprising an annular seal for engaging a relatively stationary housing or like compo nent, a carrier member coaxial with, support ted by and extending from said annular seal, a face seal component sealingly secured to said carrier member, at least one compres sion spring urging said face seal and said annular seal axially apart, a counterface component engaging said face seal component, and retaining means extending between said annular seal and said counterface component to unite the face seal component and counter face component into a single assembly wherein they are retained in axially adjoining relation with one another.

Reference will now be made to the accom panying drawing which shows one embodi ment of the invention, by way of example, and in which a fluid face seal assembly 10 com prises an annular seal 11 for engaging within a recess of a relatively stationary housing or like component, and a carrier member 12 coaxial with, supported by and extending integrally from said annular seal 11 at a radially intermediate zone 13. The carrier member 12 is formed as an extension of annular seal 11 in one piece of elastomeric material. The surface 40 of the annular seal 11 may be threaded so that the assembly can be screwed into the housing with which the assembly is to be used (not shown).The carrier member 12 has at its end remote from the annular seal 11 an annular sealing protuberance 14 moulded thereon and a radially inwardly directed flange 15 to which is sealingly secured a face seal component 16 which may be made of graphite impregnated phenolic material. The sealing protruberance 14 is compressed during assembly and fits snugly into the face seal component 16. The annular seal 11 has at least two diametrically opposed slots 17 in its inner periphery which receive mating axially directed projections 18 on the face seal component 16 to inhibit relative rotation between the annular seal 11 the face seal component 16. Alternatively the projections could be on the annular seal 11 and the slots in the face seal component 16.

Compression means, such as a spring 19, located within the carrier member 12 urges the face seal component 16 and the annular seal 11 axially apart. At its ends the spring 19 bears against pressings 20 and 21, respectively.

Pressing 20 supports and restricts the movement of the elastomeric material between the spring 19 and the face seal component 16 in both axial and radial directions.

The face seal component 16 engages a counterface component 22 which is adapted to be secured to a rotary member such a shaft (not shown) and rotates therewith. It is very convenient to supply a face seal assembly complete with its counterface component.

To enable this to be done a retainer means 23 of elastomeric material is provided within the carrier member 12 and this unites the counterface component 22 and face seal component 16 by engaging the counterface component 22 and pressing 21, for example. In the free state the retainer means 23 is held under tension by spring 19 prior to and during installation of the assembly onto a shaft.

This holds the counterface component 22 against the face seal component 16 and also stops the projections 18 from working out of the slots 17. On assembly, part 24 of retainer means 23 is compressed between the counterface component 22 and the shaft and sealingly secures the counterface component to the shaft. If a pump impellor, for example, is force fitted onto the shaft, the part 24 of the retainer means 23 is pushed by spring 19 against the back face of the impeller. On assembly on the shaft, a flange 25 on the retainer means 23 is pushed away from pres sing 21 and may act as a flinger and help to expel any fluid or moisture from inside the seal assembly, and the cylindrical part 26 will protect part of the shaft from corroding.

Cylindrical part 27 of carrier member 12 will be compressed into bellows formation when the face seal assembly 10 is installed for use and the top flange 28 of annular seal 11 has two concentric rings 29, 30 moulded into it. This helps to localise pressure due to the load of spring 19 and the load from the bellows formation in part 27.

The various parts of the face seal assembly may be made of any suitable materials.

It will be understood that the present invention is not limited to the foregoing details, which are given by way of example, as various modifications may be made to suit requirements. For example, retainer means such as item 23 may be applied to many other forms of face seal assembly to retain a counter face component against a face seal component in axially adjoining relation prior to and during installation for use.

WHAT WE CLAIM IS:- 1. A rotary shaft seal assembly for providing a seal between a shaft and a housing or other part rotatable relative to the shaft comprising an annular seal for engaging one of the relatively rotatable parts and shaped to form an extension whose end surface is sealed to a face seal component, a counterface component engaging the face seal component, resilient means urging the annular seal and the end surface of the extension apart, and a retaining means lying adjacent the shaft and engaging the counterface component and being operatively connected to the end of the resilient means remote from the counterface component; the retaining means holding the face seal component to the counterface component to form an assembly which can be installed as a single unit and adapted to be compressed when mounted on the shaft so that it forms a fluid-tight seal between the shaft and the counterface component.

2. An assembly as claimed in claim 1 in which the retaining means is composed of a resilient material and engages a rigid annular element which embraces the end of the resilient means remote from the counterface component and engages the annular seal component.

3. A rotary shaft seal assembly substantially as hereinbefore described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. the face seal component 16 and the annular seal 11 axially apart. At its ends the spring 19 bears against pressings 20 and 21, respectively. Pressing 20 supports and restricts the movement of the elastomeric material between the spring 19 and the face seal component 16 in both axial and radial directions. The face seal component 16 engages a counterface component 22 which is adapted to be secured to a rotary member such a shaft (not shown) and rotates therewith. It is very convenient to supply a face seal assembly complete with its counterface component. To enable this to be done a retainer means 23 of elastomeric material is provided within the carrier member 12 and this unites the counterface component 22 and face seal component 16 by engaging the counterface component 22 and pressing 21, for example. In the free state the retainer means 23 is held under tension by spring 19 prior to and during installation of the assembly onto a shaft. This holds the counterface component 22 against the face seal component 16 and also stops the projections 18 from working out of the slots 17. On assembly, part 24 of retainer means 23 is compressed between the counterface component 22 and the shaft and sealingly secures the counterface component to the shaft. If a pump impellor, for example, is force fitted onto the shaft, the part 24 of the retainer means 23 is pushed by spring 19 against the back face of the impeller. On assembly on the shaft, a flange 25 on the retainer means 23 is pushed away from pres sing 21 and may act as a flinger and help to expel any fluid or moisture from inside the seal assembly, and the cylindrical part 26 will protect part of the shaft from corroding. Cylindrical part 27 of carrier member 12 will be compressed into bellows formation when the face seal assembly 10 is installed for use and the top flange 28 of annular seal 11 has two concentric rings 29, 30 moulded into it. This helps to localise pressure due to the load of spring 19 and the load from the bellows formation in part 27. The various parts of the face seal assembly may be made of any suitable materials. It will be understood that the present invention is not limited to the foregoing details, which are given by way of example, as various modifications may be made to suit requirements. For example, retainer means such as item 23 may be applied to many other forms of face seal assembly to retain a counter face component against a face seal component in axially adjoining relation prior to and during installation for use. WHAT WE CLAIM IS:-

1. A rotary shaft seal assembly for providing a seal between a shaft and a housing or other part rotatable relative to the shaft comprising an annular seal for engaging one of the relatively rotatable parts and shaped to form an extension whose end surface is sealed to a face seal component, a counterface component engaging the face seal component, resilient means urging the annular seal and the end surface of the extension apart, and a retaining means lying adjacent the shaft and engaging the counterface component and being operatively connected to the end of the resilient means remote from the counterface component; the retaining means holding the face seal component to the counterface component to form an assembly which can be installed as a single unit and adapted to be compressed when mounted on the shaft so that it forms a fluid-tight seal between the shaft and the counterface component.