BEARING DEVICE FOR POKER VIBRATOR

Abstract: Bearing device particularly intended to be used in the type of poker vibrator whose rotor shaft (2) exhibits an eccentric arranged between two needle roller bearings (3, 4). Besides being carried in these bearings, the rotor shaft (2) is also carried in a deep-groove ball bearing (5) intended to take up any axial forces acting on the rotor shaft. In order to relieve it from radial forces, the deep-groove ball bearing (5) is mounted in accordance with this invention with a positive clearance in both the radial and axial directions. The radial clearance can thereby be provided either between the deep-groove ball bearing's outer race (6) and the bearing sleeve (7) or between its inner race (8) and the rotor shaft (2). The purpose of the axial clearance is to permit the radial movement of the deep-groove ball bearing (5) that is the purpose of the radial clearance.

Description: BEARING DEVICE FOR POKER VIBRATOR The present invention relates to a bearing device for the type of poker vibrator which is brought to vibrate by means of a rotor shaft designed with an eccentric rotating inside a cylindrical casing and in which the rotor shaft is carried in two needle roller bearings mounted on either side of the eccentric. The invention is especially focused on a device that relieves the loads on the bearings in which the rotor shaft is carried, whose function is to take up axial forces acting on the rotor shaft. The type of bearing in which the rotor shaft in the type of poker vi- brator in question is carried is ' , as a rule, a needle roller bearing. The reason is that the needle roller bearing has a higher load-bearing capacity for radial forces than a deep-groove ball bearing of equiva¬ lent diameter. However, the needle roller bearing cannot take up axi¬ al forces, which means that the rotor shaft must also be carried in a bearing that has this capacity, for example a deep-groove ball bear¬ ing. Owing to the radial clearances that always exist in a bearing, whether it be a needle roller bearing or a deep-groove ball bearing, load cases can arise where the deep-groove ball bearing has to take up all of the centrifugal force generated by the rotor shaft. The deep-groove ball bearing must therefore be sized to take up these radial forces as well, which means that the advantage of smaller bearing dimensions provided by the needle roller bearing cannot be exploited. The purpose of the present invention is to eliminate this disadvantage, and it is particularly characterized by the fact that the deep-groove ball bearing is given a positive cleariance in both the radial and axi¬ al directions when mounted, whereby the radial clearance is chosen so that it exceeds the radial clearance specified for the needle roller bearing. The positive radial clearance of the deep-groove ball bearing can be brought about either between the outer race of the bearing and the bearing sleeve or between the inner race and the rotor shaft. The invention will be described in greater detail below with reference to.the appended drawing where Fig 1 shows a longitudinal section OMPI St IPO through an electrically powered poker vibrator whose rotor shaft is • carried in needle roller bearings and a deep-groove ball bearing, and Fig 2 shows the rotor shaft's deep-groove ball bearing on a larger scale. I designates a poker vibrator whose vibration element consists of an eccentrically carried rotor shaft 2. The rotor shaft is driven by an electric motor M encased inside the vibrator 1 and is carried in two needle roller bearings 3 and 4 plus a deep-groove ball bearing 5 moun¬ ted at the lower end of the shaft. The needle roller bearings 3 and 4 are mounted at either end of the eccentric portion of the shaft 2, their purpose being to take up the radial forces that arise when the shaft rotates. Through their construction, the needle roller bearings are well suited to take up large radial forces, even when the bearings are of small size. The bearings are not designed to take up axial forces, however. Deep-groove ball bearing 5 is intended to take up such forces. However, the needle roller bearings exhibit some radial clearance, as a result of which the deep-groove ball bearing 5 can come to be loaded with radial forces arising from the eccentric forces of the rotor shaft The deep-groove ball bearing is also designed with a certain amount of clearance, and if this is less than the needle roller bearing's clea¬ rance, the deep-groove ball bearing 5 may be subjected to the entire eccentric force generated by the rotor shaft. The ball bearing 5 must therefore be sized to take up this load, v/hich means a larger size of the deep-groove ball bearing and thereby of the entire vibrator. By mounting the deep-groove ball bearing 5 with a positve clearance in the radial direction - which can be provided either between its outer race 6 and the bearing sleeve 7 or between its inner race 8 and the rotor shaft 2 - it is possible to eliminate the aforementioned radial load on the bearing entirely, resulting in a considerable reduction n the size of the deep-groove ball bearing 5 and thereby also of the vibrator. C PI

Claims: AMENDED CLAIMS (received by the International Bureau on 7 October 1982 (07.10.82)) 1. (original claims 1. and 2 . ) A bearing device intended to be used in the type of poker vibrator which is brought to vibrate by means of a rotor shaft designed with an eccentric rotating inside a cylindrical cas¬ ing and in which the rotor shaft is carried in two needle roller bearings mounted on either side of the eccentric, and in an additional bearing whose object is to take up axial forces on the shaft, characterized by the fact that the addi¬ tional bearing consists of a deep-groove ball bearing (5) mounted with a positive clearance in the radial direction between the bearing's outer race (6) and the bearing sleeve (7), which clearance is so chosen as to exceed the clearance specified for the needle roller bearings (3, 4). 2. (original claim 3.) A bearing device in accordance with claim 1, characterized by the fact that the ball bearing (5) is mounted with a positive clearance in the radial direction between the bearing's inner race (8) and the rotor shaft (2), which clearance is so chosen as to axceed the clearance specified for the need! * ? roller bearings (3, 4).

Inventors: BATAILLE JEAN MARIE
Applicants: BATAILLE JEAN MARIE, DYNAPAC MASKIN AB
Application year: 1982
Main classification: F16C19
IPC codes: A61H23, F16C19