Porous solid lubricant, bearing, and constant velocity universal joint

Abstract

The present invention provides a solid lubricant which is improved in the ability to retain a lubricating oil therein and in which the amount of the lubricating oil oozing out due to a deformation caused by external force can be reduced to a minimum necessary amount; and a bearing or constant velocity universal joint containing the lubricant enclosed therein. The porous solid lubricant comprises a lubricating component comprising a lubricating oil and a resin component as essential components, wherein the resin component is a solid matter having porosity imparted thereto by foaming and the lubricating component is occluded in the resin. Since the lubricating component is occluded in the resin in a foamed state, the resin, which is flexible, deforms upon reception of an external force, e.g., compression, expansion, flexing, or torsion, to ooze out the lubricating component. Thus, the lubricating component is gradually released from spaces among the molecules of the resin. The amount of the lubricating oil which can be retained is larger than that of the lubricating oil held by mere infiltration into the pores. With the lubricant, the bearing can have a long life, can be operated even at a high revolution, and can be produced at low cost. Furthermore, the constant velocity universal joint can have a long life and be reduced in damage to the boot made of rubber.

Description

technical field [0001] The present invention relates to a porous solid lubricant capable of supplying lubricating oil to a sliding part or a rotating part of a mechanical device, a bearing and a constant velocity universal joint using the same. Background technique [0002] Generally, lubricants are used in sliding parts, rotating parts, and the like of most machines represented by automobiles and industrial machines. Lubricants are broadly classified into liquid lubricants and solid lubricants, and there are also known greases that grow lubricating oil to make them self-contained, and solid lubricants that keep liquid lubricants and prevent them from scattering or running. [0003] For example, there is known a solid lubricant ( Patent Documents 1, 2, 3). [0004] In addition, a self-lubricating polyurethane elastomer is known in which polyol and diisocyanate, which are polyurethane raw materials, are reacted in a lubricating component in the presence of a lubricant (Pate...

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Problems solved by technology

[0019] In addition, in the rolling bearing filled with the solid lubricant based on the above-mentioned prior art, there are following disadvantages, that is, the service life is short, and it is easy to burn in high-speed rotation. melted, making it unusable

In addition, in the full filling method of filling the solid lubricant without gaps, there is a problem that the solid lubricant shrinks during the post-cooling process of solidifying the solid lubricant in the bearing, so that the lubricant itself is adsorbed on the bearing. The rolling element tends to increase the rotational torque, which leads to the problem of easy heat dissipation

[0020] In the process of manufacturing such a solid lubricant, in order to reliably impregnate lubricating oil or grease, a large number of manufacturing steps are required, which also makes it difficult to meet the demand for cost reduction.

[0021] In addition, if the remaining lubricating oil comes into contact with a rubber exterior such as a protective cover installed to cover the shaft and the outer ring in the constant velocity universal joint, the additives of the lubricating oil may corrode or deteriorate the rubber.

[0022] Furthermore, since a large number of steps are required to reliably impregnate lubricating oil or grease, there is a problem in manufacturing constant velocity universal joints at low cost.

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