JP5045554B2 - Rolling bearing device - Google Patents

Description

  The present invention relates to a rolling bearing device used for a main shaft of a machine tool.

  Conventionally, oil lubrication and grease lubrication are known as lubrication for a rolling bearing device that rotatably supports a main shaft of a machine tool.

In recent years, grease lubrication has attracted attention from the viewpoint of energy saving and environmental load reduction (see, for example, Patent Document 1 and Patent Document 2).
JP 2005-188757 A JP 2005-201346 A

  However, grease lubrication has a large temperature rise due to stirring resistance, has a limited grease life, and requires regular maintenance. Therefore, grease lubrication is inferior in performance to oil lubrication. Oil-air lubrication has been common for rolling bearings that rotatably support a main shaft.

  Oil-air lubrication has high lubrication performance for high-speed rotation, but requires an expensive oil-air lubrication device, and wind noise (noise) due to air becomes a problem.

  An object of the present invention is to provide a rolling bearing device that solves the above-described problems, is inexpensive, and has high lubrication performance against high-speed rotation.

A rolling bearing device according to the present invention is a rolling bearing device in which an inner ring of a rolling bearing is fixed to a rotating shaft via an inner ring spacer that is in contact with one end surface thereof, and the inner ring spacer has a lubricant reservoir space therein. those hollow, our Ri is assumed that the rolling bearing by the lubricant sealed in the lubricant reservoir space is lubricated, the inner ring spacer, and the lubricant supply path to the rolling bearing, the lubricant supply A lid that opens and closes the path and opens the lubricant supply path by centrifugal force. The larger the centrifugal force increases as the rotating shaft rotates at a higher speed, the greater the amount of opening of the lubricant supply path increases. Is supplied .

  A rolling bearing usually includes an inner ring, an outer ring, rolling elements such as a plurality of balls interposed therebetween, and a cage.

  As the lubricant, grease, grease base oil, oil (lubricating oil) or the like is used.

  While the rotating shaft is stopped, the lid portion of the inner ring spacer closes the lubricating oil supply path, so that the lubricant does not leak.

  When the rotating shaft rotates, the lid portion opens the lubricating oil supply path by centrifugal force, and the lubricating oil is supplied into the bearing from here. Since the centrifugal force is small during low-speed rotation, the opening of the lubricating oil supply path is small, and the amount of lubricant supplied to the bearing is small. During high-speed rotation, the centrifugal force is large, so the opening of the lubricating oil supply path is large, and the amount of lubricant that cooperates with the bearing is large.

  In the rolling bearing device of the present invention, for example, the hollow inner ring spacer has a first end wall that contacts one end surface of the inner ring of the rolling bearing, a second end wall on the opposite side that contacts the rotating shaft side, A bottom wall that is connected to the inner periphery of the first end wall and the second end wall and fits on the rotation axis; a base end portion is fixedly provided on the second end wall; and a free end portion is formed on the first end wall. A lid portion in contact with the outer periphery, and a lubricant supply path is formed between the outer periphery of the first end wall and the free end portion of the lid portion, and the free end portion of the lid portion is the first when the rotating shaft is stopped. The lubricant supply path is closed in pressure contact with the outer periphery of the end wall, and when the rotary shaft rotates, the free end of the lid part is elastically deformed by centrifugal force to move away from the outer periphery of the first end wall. The lubricant supply path is opened.

  According to the rolling bearing device of the present invention, as described above, when the rotary shaft rotates, the lubricant can be reliably supplied into the bearing to lubricate the bearing, and an expensive oil-air lubrication device or the like can be provided. It is unnecessary and can be configured at low cost.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an example of a rolling bearing device provided with a rolling bearing (2) that rotatably supports a main shaft (rotating shaft) (1) of a machine tool. In the following description, the left and right in FIG.

  In this example, the rolling bearing (2) is a ball bearing and includes an inner ring (3), an outer ring (4), a plurality of balls (rolling elements) (5) interposed between them, and a cage (6). It is made up of.

  The inner ring (3) and the inner ring spacer (7) in contact with the right end face of the inner ring (3) are fitted into the small diameter part (1b) on the right side of the large diameter part (1a) of the main shaft (1), and the annular part at the right end of the large diameter part (1a) It is clamped between the end face (1c) and the cylindrical body (8) fixed to the small diameter part (1b). Similarly, the outer ring (4) is fixed to the housing (10) which is a fixed part via an outer ring spacer (9).

  The inner ring spacer (7) is a hollow shape having a lubricant reservoir space (11) inside, and opens and closes the lubricant supply path (12) and the supply path (12) into the bearing (2). And a lid (13) that opens the supply path (12) by centrifugal force.

  In this example, the inner ring spacer (7) is integrally formed with a cylindrical bottom wall (14) and a perforated disk-shaped first end wall (15) projecting from the left end face to the outer peripheral side. From the inner member (16) and the outer member (18) integrally formed with the perforated disc-shaped second end wall (17) and the cylindrical lid portion (13) extending leftward from the outer peripheral edge thereof It is configured. The bottom wall (14) fits into the main shaft small diameter portion (1b), and the first end wall (15) is in contact with the right end surface of the inner ring (3). The inner peripheral portion of the second end wall (17) is fixed to the right end surface of the bottom wall (14). The base end on the right side of the lid (13) is integrated with the outer peripheral edge of the second end wall (17), and the free end on the left extends to the periphery of the first end wall (15). A supply path (12) is formed between the outer peripheral surface of the first end wall (15) and the free end of the lid portion (13). In the space (11) in the inner ring spacer (7), an appropriate lubricant such as grease, grease base oil, or oil (lubricating oil) is sealed.

  The lid (13) is thinner than the other walls (14) (15) (17). When the main shaft (1) is stopped and centrifugal force does not act on the inner ring spacer (7), the free end of the lid (13) is elastically applied to the outer periphery of the first end wall (15). The supply path (12) is closed in pressure contact with the surface. When the main shaft (1) rotates and centrifugal force acts on the inner ring spacer (7), the free end side of the lid (13) is elastically deformed to the outer peripheral side, and the first end wall (15). Away from, open the supply channel (12). Then, lubricant such as grease base oil and oil in the space (11) flows out of the open supply passage (12) by centrifugal force and is supplied into the bearing (2). As the spindle (1) rotates at a high speed and the centrifugal force increases, the amount of opening of the supply passage (12) increases and a larger amount of lubricant is supplied.

  In the above embodiment, the inner ring spacer (7) is composed of two members, the inner member (16) and the outer member (18). However, the configuration of the inner ring spacer is not limited to this and can be changed as appropriate. It is.

  For example, you may make it fix the base end part of the cover part made separately from the 2nd end wall to the outer periphery of the 2nd end wall. In such a case, by appropriately selecting the material of the lid portion, it is possible to more reliably open and close the lubricant supply path by the lid portion during rotation and when stopped. In that case, the bottom wall and the first and second end walls may be integrated, or may be composed of two or more members.

  The overall configuration of the rolling bearing device is not limited to that of the above embodiment, and can be changed as appropriate.

  Furthermore, the present invention can also be applied to a rolling bearing device other than the main spindle of the machine tool.

FIG. 1 is a longitudinal sectional view of a rolling bearing device showing an embodiment of the present invention.

Explanation of symbols

(1) Main shaft (rotating shaft)
(2) Rolling bearing
(3) Inner ring
(7) Inner ring spacer
(11) Lubricant pool space
(12) Lubricant supply path
(13) Lid
(15) First end wall
(17) Second end wall

Claims (3)

In the rolling bearing device in which the inner ring of the rolling bearing is fixed to the rotating shaft via an inner ring spacer that is in contact with one end surface thereof,
The inner ring loci, those hollow having a lubricant reservoir space therein, our Ri rolling bearing is intended to be lubricated by the lubricant sealed in the lubricant reservoir space, the inner ring spacer, rolling a lubricant supply path to the bearing, the lubricant opening and closing the supply path and the lid to open the lubricant supply passage is provided by the centrifugal force, the greater the centrifugal force the rotating shaft is rotated at a high speed is, the lubricant A rolling bearing device characterized in that the amount of opening of the supply path is increased and a large amount of lubricant is supplied . A hollow inner ring spacer includes a first end wall that contacts one end surface of the inner ring of the rolling bearing, a second end wall on the opposite side that contacts the rotating shaft side, a first end wall, and a second end wall. A bottom wall that connects the inner circumference of the first end wall and a base wall that is fixed to the second end wall, and a free end that is in contact with the outer circumference of the first end wall. 1 between the outer periphery of the end wall 1 and the free end of the lid is a lubricant supply path, and when the rotary shaft is stopped, the free end of the lid is pressed against the outer periphery of the first end wall, The lubricant supply path is closed, and when the rotary shaft rotates, the free end portion of the lid portion is elastically deformed by centrifugal force so that the lubricant supply path is opened away from the outer periphery of the first end wall. The inner ring spacer includes an inner member in which the first end wall and the bottom wall are integrally formed, and an outer member in which the second end wall and the lid portion are integrally formed. Saha First end wall, the rolling bearing apparatus according to claim 1, characterized in that it is made thinner than the thickness of the bottom wall and the second end wall.   The rotating shaft has a large diameter portion and a small diameter portion connected thereto, and the inner ring and the inner ring spacer are fitted to the small diameter portion of the rotating shaft with the first end wall of the inner ring spacer in contact with the inner ring. The rolling bearing device according to claim 2, wherein the rolling bearing device is sandwiched between an annular end surface of the large-diameter portion of the rotating shaft and a cylindrical body fixed to the small-diameter portion.

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