A SPHERICAL ROLLER BEARING WITH INTEGRATED LOCKING DEVICE

The present invention refers to a spherical roller bearing provided with integrated locking device.

Rolling bearings are mounted on a rotating or non-rotating shaft either as a locating bearing or as a non-locating bearing for supporting a machine component of arbitrary design, and when such bearings shall be mounted independently if it shall act as a locating bearing or as a non-locating bearing it is evident that it must be possible to arrest the inner race ring in a well defined exact location in a simple and reliable manner.

The most commonly used components for such arresting of a bearing with a taper bore is an adapter sleeve having an outer envelope surface with a taper corresponding to that of the bearing bore. The adapter sleeve, which is slotted, is used together with a lock nut and a locking device, making it possible to arrest the bearing ring axially on the shaft. However, the taper required results in a rather large big end thickness of the adapter sleeve, which in turn means that a part of the cross section available for accommodating the bearing is required for the large section of the adapter sleeve, and consequently the assembly space will permit only a limited bearing size.

Spherical roller bearings or similar self-aligning bearings are typically mounted with an interference fit. With the above mentioned commonly used method and components it is required quite a high force for tightening the lock nut whereby it is very difficult to give the bearing the desired interference fit and a desired residual clearance, which is a prerequisite for a well functioning bearing.

There are methods developed for measuring the resulting interference fit and residual clearance, but these are complicated and can not be used in a secure manner, particularly with an internally sealed bearing.

In accordance with another solution, a thin-walled sleeve has an outer envelope surface with a saw-tooth profile and the bearing bore has a corresponding saw-tooth profile. When these saw-toothed profiles are axially displaced relative to each other, a very safe and reliable locking of the bearing on the shaft is achieved, whereby the thickness of the thin-walled sleeve is much smaller than that of the common adapter sleeve.

Such arrangements have been used in plummer block housings, where the bearing has been mounted on the shaft together with an annular flange for tightening devices, such as set screws arranged to extend through threaded bores extending in the longitudinal direction of the shaft for being tightened thus that they subject the bearing inner ring and the thin-walled sleeve to a force, thereby increasing the grip between bearing inner ring and sleeve and between sleeve and a shaft, on which the spherical bearing is to be arrested.

The plummer block housing is provided with sealing members positioned outside the bearing.

The position and direction of the threaded through bores in the annular flange, often will make it difficult to tighten or loosen the set screws, as the tool to be used not always can be easily inserted in the screw head groove.

The purpose of the present invention therefore now is to provide a spherical roller bearing, provided with integrated locking device, with tapering cooperating surfaces provided on one hand in the outer envelope surface of a thin-walled sleeve and on the other hand in the inner envelope surface of the bearing inner ring, which forms a self-contained unit which can be easily and readily mounted and dismounted without being influenced by the drawbacks experienced with earlier solutions such as described hereabove and this is achieved in that the bearing and locking device unit has been given the features defined in the accompanying claims.

Hereinafter the invention will be described with reference to a non-limiting embodiment illustrated in the accompanying drawing.

Fig. 1 shows in a side view a bearing with a locking device in accordance with the invention as seen in mounted position, and

Fig. 2 is a cross section along line A - A in Fig. 1.

The side view of Fig. 1 shows the bearing 1 and portions of the inner thin- walled sleeve 5, with its slotted portion 5a, and three set screws 7, extending through an annular flange 6.

From the cross section according to Fig. 2, which is seen along line A - A in Fig. 1, it can be seen how the two-row spherical roller bearing 1, forms an integrated unit with the locking device 2, which is formed as a thin-walled slotted sleeve 5 with saw-tooth tapering cooperating 3, 4 surfaces provided on one hand in the outer envelope surface of the thin-walled sleeve 5 and on the other hand in the inner envelope surface of the bearing inner ring Ia.

An annular flange 6 for tightening devices in form of set screws 7 is arranged for displacing the sleeve 5 and the bearing inner ring Ia relative to each other, thereby increasing the grip between bearing inner ring Ia and sleeve 5 and between sleeve 5 and a (not shown) shaft, on which the spherical bearing is to be arrested.

The set screws 7 are arranged to extend through threaded bores 8 in said annular flange 6. The threaded bores 8 thereby are arranged inclined under an acute angle to the axial extension of the bearing 1, thereby facilitating access to the screw head with a tool.

A separate loose thrust flange 9 is provided between the bearing inner ring Ia and said annular flange 6, and this separate loose thrust flange 9 has a surface 9a facing the annular flange 6, which is inclined, thus that it is substantially perpendicular to the extension of said inclined bores 8 in the annular flange 6.

The annular flange 6 is axially non-displaceable relative to the thin-walled sleeve 5, by the fact that the inner thin-walled sleeve 5 at its outer envelope surface has a circumferential groove 10 axially spaced apart from its tapering

surfaces, in which groove 10 a circumferential ridge 11 extending inwardly from the inner envelope surface of the annular flange 6 enters.

The spherical roller bearing 1 is equipped with integrated sealing means 12, whereby the entire unit can be mounted for delivery from the manufacturing factory as a self-contained unit, which is sealed off, provided with a proper volume of lubricating grease, and is ready to be mounted on a shaft simply by loosening the set screws, pushing up the unit on the shaft, and thereupon tightening the screws again, when the bearing has been pushed up to the desired position.

In the embodiment illustrated the unit has three tightening set screws but this is not a critical number, and it is possible to use any number of corresponding fastening and tightening devices.

The invention is not limited to the embodiment illustrated and described in connection to the drawing, but modifications and variants are possible within the scope of the accompanying claims.