AU2005203166A1 - A Combined Floating S. Seal System - Google Patents

Description

Australia Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT A COMBINED FLOATING SPINDLE SEAL SYSTEM The following statement is a full description of this invention, including the best method of performing it known to me: SA COMBINED FLOATING SPINDLE SEAL SYSTEM This invention relates to improvements in rotating glands for conveying a gas or liquid through a rotating assembly.

Established rotating glands are based around bearings which are arranged in a linear or axial INDfashion, to provide adequate radial and axial alignment, along with a seal of some sort at one end of the above bearing assembly. This makes a compact, small diameter unit ideal for C many industrial purposes, but some uses would be better suited by having a shorter gland.

0 C The best known system that provides a shorter rotating gland is made possible by incorporating the sealing component inside or co-axially with a larger single bearing (a separate patent application covers this invention). Therefore, the ultimate in shortness is limited only by the bearing thickness, and the required room for air passages, sealing system, and distribution ports. The difficulty is in the small components, the amount of accurate machining required, and the necessity of tight tolerances.

Convention has been to accurately and fully machine a housing to match the exterior of the bearing, and accurately machine the depth to suit the bearing or bearings, along with any retaining components, like circlips. When operated in hostile environments, added complexity is required to minimize contamination of the bearing/s and seals. These additions also add to the length of the gland.

This solution addresses these problems. A concentric, clamp together, co-axial rotating gland, consisting of a single, relatively large bearing that is clamped between two bodies, for instance, a washer or plate or component and a base, or other component with the seal component located co-axially within the bearing center thereby allowing liquid or gas transferal in a short compact unit. A further refinement which can help minimize the total length is for the clamping ring to clamp down onto standard ball bearing race's locating circlip. These standard supply, bearings, with the attached circlip, are often used to help locate the bearing axially, for instance in gearboxes. This clamping system provides room for the retaining bolt heads or other means of locating to exist below the bearing face, allowing a shorter overall gland. The pitch circle diameter of these retaining bolts provides minimal clearance of the bearing's circlip, therefore maintaining it's position.

A small bearing locating recess or depression is machined or formed into the base or body to locate and align the bearing, and it's components. Thus the bearing and it's related and supported components is securely located, and sealed away from outside contaminants. Sufficient air passages are provided to connect to the external requirements. One such means is a flat cir- ND cular air passage body, that is secured to the center spindle via a standard hollow bolt with a peripheral drilled hole, as is often used in pneumatics. This circular body can have a recess of 0 a similar diameter to the bearing, and when mounted close to it, provides added bearing protection, in a minimal overall length. Alternatively, a straight fitting can be attached, providing an Saxial fluid flow.

This invention consists of a new way to support and locate the sealing system, which is a conventional oil type seal onto a shaft. Conventionally, a face seal, like a water pump seal can be used, but this is expensive and requires accurate machining. Another conventional method is to machine the shaft integral with either the body or the rotating bit, and provide a seal to match. This seal can be mounted inside the bearing support shaft, and retained by staking, or by other means. A short, smooth, and often hardened, hollow shaft or spindle is fitted to the other piece, which may be the base, or 'body'. If this spindle were machined from the parent metal of this 'body', it would have to be machined very smooth, and very concentric, and then probably need to be hardened. Complex and expensive Or, a short, small diameter, hardened, ground, and chromed shaft or spindle can be interference fit into the body. But again, the accuracy required to get the exact concentric fitting is difficult, especially when shortness is required. And, if any damage or wear occurs, the entire body would need to be replaced. This refinement locates this hard smooth hollow spindle in a conventional ring. This retains the shaft, provides for self alignment, and even some degree of misalignment as it floats in the ring. This allows hard, chromed, smooth, commercial, shafting to be used, and replaced if needed. Because the pressures are identical on each end, this spindle truly floats inside the gland.

Alternatively, the seal can be mounted in the base, and the spindle and ring can be mounted concentric to the bearing in the bearing support shaft.

The gland can be made of any suitable material, such as metal, or plastic.

3 tn To assist with understanding the invention, reference will now be made to accompanying 0 0 drawings, which show one example of the invention.

C-I

In the drawings: FIG. 1 shows a side view of one example of a concentric, clamp together, co-axial, floating INO spindle, rotating gland, according to this invention: FIG. 2 shows an exploded isometric drawing of the main components of one example of this invention: FIG. 3 shows an exploded cross section of the main components of one example of this invention; FIG. 4 shows an isometric drawing of one example of this invention.

Referring to Figure 1, the shortness is evident. Referring to drawings in general, the bearing 2 is supported and located by the bearing locating recess 6 in the body 1. The standard bearing locating circlip 4 is clamped and located by the bearing clamp ring 5 via bolts 10. These bolts 10 control the bearing locating circlip 4, keeping it within it's groove. The bolts screw into threaded holes 11 provided on the body 1.

A bearing shaft 3 is pressed into the bearing 2. The seal 9 is pressed into the end of the bearing shaft 3. The other end of the bearing shaft 3 is usually threaded to take conventional gas or fluid fittings.

The spindle 8 is a hollow, polished chrome plated shaft which fits neatly into the ring 7.

This supports the spindle 8 while allowing some flexibility for self alignment. The seal 9 seals onto this spindle 8. This is the subject of this patent.

Air passages, 12 provide for flow of substance from the bearing shaft 3 through the spindle 8 to the other threaded passage on the body 1.

Claims (2)

1. A combined floating spindle, seal system wherein the spindle or shaft is supported by an C1 'O'ring or other flexible sealant ring to control rotation and position, while providing controlled movement to allow self alignment with the sealing mechanism and

2. A combined floating spindle, seal system as in claim 1 substantially as herein described tC< with reference to the accompanying description and drawings. 0 c-