Surveying device for the running parameters of railway bearings

Surveying device (1) for the running parameters of railway contact bearings (2) which is provided with a rotating race (3) and a non-rotating race (4) which are coaxial to a rotation axis (A) of the railway contact bearing (2) itself, the device (1) being provided with a sealing shield (5) which is mounted onto the non-rotating race (4); and which is also provided with a sealing lining/covering (7) which is integral with the shield (5), and which is in contact with a sliding surface (11s) which is in turn integral with the rotating race (3): the device also being provided with a signal generating element (15) which is integral with the sliding surfaces (3s) (11s) themselves and which is arranged inside the shield (5); and which is also provided with a sensor (16), which faces the generating element (15) in order to read the signal itself, and which is itself integral with the shield (5) in a position which is outside the railway bearing (2).

The present invention relates to a surveying device for the running parameters of railway bearings.

The Italian patent Application No. T096A000752 describes a surveying device for the rotation speed applied to a bearing for railway axles, and it comprises a magnetic wheel which generates impulses; a sensor which faces the magnetic wheel in order to receive the impulses; two sealing shields which are mounted onto a rotating race and a non-rotating race of the bearing, and which, respectively, support the magnetic wheel and the sensor.

The aim of the present invention is to produce a surveying device for the running parameters of railway bearings, which presents better sealing qualities than those presented by the device described in the above-mentioned patent application, and which is also defined by a reduced number of components, so that it is both simple and cost-effective to manufacture.

According to the present invention, a surveying device for the running parameters of railway bearing will be produced which is provided with a rotating race and a non-rotating race of the railway bearing itself, the device comprising:a sealing shield which is mounted on the non-rotating race;a sealing covering which is integral with the shield and which is in contact with a sliding surface which is integral with the rotating race;a signal generating element which is integral with the sliding surface itself and which is arranged outside the shield; anda sensor, which faces the generating element in order to read the signal itself, and which sensor itself is also integral with the shield in a position which is outside the railway bearing.

With reference toFIG. 1, the number1indicates, in its entirety, a surveying device for the running parameters of a railway bearing2, shown as a tapered roller bearing, which comprises a rotating race3and a non-rotating race4which are coaxial to each other and to a rotation axis A (FIG. 3) of the railway bearing2itself.

The device1comprises a sealing shield5which is mounted onto the non-rotating race4, an annular element6which is mounted onto the rotating race3, and a sealing covering7which is integral with the shield5and which is provided with a lip8which his turned towards the element6.

In particular, in an axial section which is intended as a section obtained by means of a passing plane for the axis A and for any diameter of the railway bearing2, the shield5presents a shape which is substantially in the form of an L, and comprises a cylindrical wall9which is mounted inside and in contact with the non-rotating race4, and an annular wall10, which extends transversally to the axis A between the two races3and4starting from the wall9towards the race3, and which supports the covering7in correspondence with one of its own internal radial free ends.

The element6comprises a cylindrical wall11, which is shrink fit onto an internal radial surface3sof the race3, and which is radially delimited towards the inside by a cylindrical surface11swhich is arranged in sliding contact with the lip8. The element6also comprises an annular wall12, which is transverse to the axis A and is axially staggered towards the outside of the railway bearing2in relation to the wall10, and a further cylindrical wall13, which is integral with the wall12, and which extends transversally to the wall12itself towards the shield5while overlapping the surface11sin an axial direction.

The device1also comprises a signal generating element15, and a sensor16which faces the signal generating element15in order to read the signal itself.

The signal generating element15is defined by a phonic wheel which is obtained directly on the wall13by alternating a number of teeth17and a number of notches18in relation to each other, the rotation of which around the axis A, together with the rotating race3of the railway bearing2, turns the wall13into an emission wall which emits a signal which is captured by the sensor16. As an alternative to the teeth17and the notches18, it is possible to provide a number of magnetised areas which have alternating magnetic fields: the effect on the sensor16is, however identical, as both the teeth17and the positively magnetised areas can be considered to be the equivalent of positive poles, and both the notches18and the negatively magnetised areas can be considered to be the equivalent of negative poles or vice versa.

As is illustrated inFIGS. 1,2and3, the sensor16is mounted onto an external surface19of the wall10, is physically separate from the shield5, and comprises a main body20and two fixing screws21for fixing the body20to the wall10itself. As an alternative to the fixing screws21, the sensor16can also comprise a rapid coupling system or any other element which is suitable for guaranteeing the rapid removal of the sensor16in the case of any damage or breakdown.

Furthermore, the sensor16comprises a connecting cable23which connects the sensor16itself to a peripheral decoding unit (of a well-known kind, which is not illustrated), and a sensitive element22, which is arranged in a position facing the wall13on a cylindrical plane P1which is coaxial to the rotation axis A and which, as is illustrated inFIGS. 6 and 7, extends around the axis A itself in a circumference arc which is of a determined width or which, alternatively, is equal to a circle.

The surveying device which has just been described is particularly suitable for being applied to a railway bearing2and, by simply inserting a number of analogous transducers46to the sensitive element22inside the sensor16, it can also be used for surveying a number of different parameters such as, for example, the speed and direction of rotation, the temperature, vibrations, humidity or dampness, or the eventual presence of fumes or smoke. Furthermore, if the element5is produced as has been described above, it is possible to reduce production costs and it is also possible to use the sealing covering7by exploiting its well-known characteristics of sealing and efficiency.

The forms of embodiment which are illustrated inFIGS. 8,9,10,11and12relate, respectively, to a surveying device1a,1b,1c,1dand1ewhich is analogous to the device1, from which:

the device1adiffers from the device1due to the fact that, while the wall13still extends transversally to the wall12, it is opposite the shield5and overlaps the surface3sin an axial direction;

the device1bdiffers from the device1due to the fact that the annular element6is not provided with a large part of the wall11, and so the lip8is arranged in direct sliding contact with the surface3sas well as with the surface11s;

the device1cdiffers from the device1due to the fact that the wall11extends opposite the shield5leaving the lip8in direct sliding contact with the surface3s, and also due to the fact that the wall13still extends transversally to the wall12, but opposite the shield5and so overlapping the wall11in an axial direction;

the device1ddiffers from the device1due to the fact that the wall12presents a thickness which is such as to completely incorporate the wall13inside one of its own external free radial ends: and

the device1ediffers from the device1due to the fact that the wall12presents a thickness which is such as to completely incorporate the wall13inside one of its own free radial ends, and also due to the fact that there is no wall11, so the lip8is arranged in direct sliding contact with the surface3sand the element6is presented in its simplest form.

So, the body20of the sensor16presents an appendage42, which is arranged transversally to the axis A, and which extends frontally to the wall12. While the sensitive element22is supported by the appendage42, it is arranged in a position which faces the wall12on an annular plane P2which is transverse to the rotation axis A and, as is illustrated inFIGS. 5 and 6, it extends around the axis A itself in a circumference arc of a determined width or which, alternatively, is equal to a circle.

Furthermore, the device41differs from the device1due to the fact that the wall13no longer extends towards the shield5, but, instead, it extends towards the outside of the railway bearing2in such a way as to define an external radial appendage13which is substantially in the shape of a truncated cone. The appendage13together with the body20of the sensor16creates a hollow space44, which is provided with a window45which substantially faces the sensitive element22.

The surveying device41which has just been described presents the same advantages as the device1, to which should be added the centrifugal effect which results in the expulsion of any eventual detritus towards the hollow space44in dynamic conditions.

According to a form of embodiment which is not illustrated in the attached drawings, but which may be easily deduced in accordance with the above-written description, the sensor16, instead of being physically separate from the shield5, is incorporated into the shield5itself, and is defined by a body which is rendered integral with the second shield itself by means of cold pressing, or welding, resin finishing or moulding, or by means of other well-known techniques.

It is intended that the present invention should not be limited to the forms of embodiment which are herein described and illustrated, which are to be considered as examples of forms of embodiment of the surveying device for the running parameters of railway bearings, and which may be subject to further modifications in terms of the shape and disposition of the parts, as well as details pertaining to construction and assembly.