Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
  • F16C33/30—Parts of ball or roller bearings
  • F16C33/38—Ball cages
  • F16C33/41—Ball cages comb-shaped
  • F16C33/412—Massive or moulded comb cages, e.g. snap ball cages
  • F16C33/414—Massive or moulded comb cages, e.g. snap ball cages formed as one-piece cages, i.e. monoblock comb cages
  • F16C33/416—Massive or moulded comb cages, e.g. snap ball cages formed as one-piece cages, i.e. monoblock comb cages made from plastic, e.g. injection moulded comb cages
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
  • F16C33/30—Parts of ball or roller bearings
  • F16C33/38—Ball cages
  • F16C33/41—Ball cages comb-shaped
  • F16C33/418—Details of individual pockets, e.g. shape or ball retaining means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
  • F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
  • F16C19/04—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly
  • F16C19/06—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly with a single row or balls

Definitions

• the present invention relates to the field of cages made of synthetic material intended for rigid ball bearings.
• the cages used in the bearings are intended to permanently maintain a regular circumferential spacing between the rolling elements.
• the synthetic cages are produced by injection molding of a plastic material, for example polyamide 6.6, loaded or not with a reinforcing material such as glass fibers.
• These cages consist of an annular ring provided with spherical cells opening axially on one face of the ring and radially on both sides of the ring, each cell extending axially by tongues directed in a direction axially opposite the bottom of the socket.
• Such a type of cage is mounted by axial snap-fastening on the row of balls of the bearing, said balls coming to adjust with very little play in the cells.
• the enveloping spherical shape of the cells ensures the axial retention of the cage on the row of balls and allows the centering of the cage relative to the bearing rings.
• inner edges of cells means the edges of cells located towards the axis of rotation of the bearing.
• lower part of the cell means the part of the cell closest to the axis of rotation of the bearing.
• the object of the present invention is to remedy the drawbacks of conventional cages and to propose a cage the shape of which allows to improve the conditions of ball-cell contact by moving the contact zone away from the sharp edge.
• the cage device according to the invention is of the type intended for holding balls in a bearing comprising at least one row of balls arranged between two raceways.
• the cage comprises an annular part axially adjacent to the balls and a plurality of cells in each of which is arranged a ball.
• a cell is formed by a concave surface, the cells opening axially on one face of the ring and radially on both sides of the ring, said cells being separated by the spacing parts extending opposite the ring. by tabs.
• the concave surface comprises a frustoconical portion connecting to a spherical portion.
• the frustoconical portion is disposed along the inner edge of the cell and is connected to the spherical portion which occupies the rest of the concave surface, the conical portion going in the direction of closing of the axis of revolution of the cage.
• the spherical portion is arranged on the outer edge of the cage. This removes the ball-cell contact area from the inner edges of the cell, thus avoiding edge contact on sharp angles between balls and cells, which considerably improves the characteristics of contact pressures at this level, with consequent noticeably reduced cage wear.
• lubrication is improved due to the conical shape at the base of the cell which gives the lubricant more space.
• a reservoir of lubricant is thus formed at the base of the cell, which is entirely beneficial for the proper functioning of the bearing.
• the cage according to the invention retains its capacity for retaining the balls in the cage cells, both in the axial direction and in the radial direction.
• the frustoconical and spherical portions are connected tangentially. In another embodiment of the invention, the frustoconical and spherical portions are connected in a secant manner, preferably by forming a re-entrant angle or a hollow.
• the distance d between the base of the truncated cone and the center of the spherical portion of the cell is between zero and D / 2-Y, D being the diameter of the circle passing through the centers of the spherical portions of the cells, Y being equal to (D; 2 + D p 2 - D a 2 ) / (4 * D p ).
• the diameter B of the base of the truncated cone is between 2 * X and D ⁇ ,, D ⁇ ., Being the diameter of the cell.
• the present invention also relates to a ball bearing comprising a cage as described above.
• the cage will thus offer resistance to wear due to the improvement of the so-called "edge" contacts between the balls and the cage and to better lubrication, thereby reducing the risks of premature failure of the bearings due to cage rupture.
• the present invention will be better understood on studying the detailed description of an embodiment taken by way of nonlimiting example and illustrated by the appended drawings, in which: FIG.
• Figure 1 is a view in axial section of a conventional ball bearing
• Figure 2 is a partial front view of a conventional cage
• Figure 3 is a sectional view along III-III of Figure 1
• Figure 4 is a schematic view of the contact surface between the cellular balls in a conventional cage
• Figure 5 is a schematic view showing the distribution of contact pressures in two perpendicular directions in the case of a conventional cage
• Figure 6 is a view similar to Figure 5 for the cage according to the invention
• Figure 7 is a partial cross-sectional view of a cage according to the invention
• Figure 8 is a perspective view of a cage according to the invention.
• the bearing 1 of the conventional type comprises an outer ring 2 provided on its bore with an O-ring raceway 3, an inner ring 4 provided on its outer surface with a raceway O-ring bearing 5, and a row of rolling elements 6, for example balls, arranged between the raceway 3 of the outer ring 2 and the raceway 5 of the inner ring 4.
• the row of rolling elements 6 is held by a cage 7 made of synthetic material and comprising an annular part 8 disposed between the outer 2 and inner rings 4 on one side of the row of rolling elements 6, and spacing parts 9 arranged between said outer 2 and inner 4 rings and between the elements rolling 6.
• the ring 8 and the spacing parts 9 define a plurality of spherical cells 10 circumferentially regularly distributed and in each of which is disposed a rolling element 6.
• the spacing parts 9 end axially opposite the ring 8 by tongues 11 ensuring the maintenance of the cage 7 relative to the rolling elements 6.
• FIG. 4 shows the theoretical contact surface between a cell and a rolling element. To study the behavior of the cage, we divided this surface into several sectors. It has been observed that the sector shown in gray shows the highest contact pressures between the cage and the rolling element. This sector, shown in gray, corresponds to the inner edge of the cell near a tongue of the cage located in the direction of rotation.
• the cage 17 comprises concave cells 22 provided with a frustoconical portion connecting to a portion spherical 23.
• the frusto-conical portion 24 is disposed on the inner edge of the cage cell and is closed in the direction of the axis of revolution of the cage, the spherical portion 23 occupying the rest of the cell.
• These spherical 23 and frustoconical 24 portions can either be connected tangentially, or be connected in a secant fashion at an angle of a few degrees. It can be seen, in particular in FIG.
• D a is the diameter of a cell
• D j is the diameter of the cage bore
• D is the diameter of the circle passing through the center of the spherical portions of the cells.
• O is located on the axis of rotation of the cage, the OY axis passing through the center of the cell and the OX axis being perpendicular to the OY axis in O.
• B is the diameter of the base of the truncated cone, that is to say the diameter at the connection between the frustoconical portion and the spherical portion; d is the distance between the base of the truncated cone and the center of the spherical portion of the cell; ⁇ is the angle of the truncated cone.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Rolling Contact Bearings (AREA)

Applications Claiming Priority (3)

Publications (1)

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ID=9523298

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (5)

Family Cites Families (11)

• 1998
  • 1998-02-24 FR FR9802215A patent/FR2775323B1/fr not_active Expired - Fee Related
• 1999
  • 1999-02-15 US US09/403,299 patent/US6200038B1/en not_active Expired - Fee Related
  • 1999-02-15 WO PCT/FR1999/000329 patent/WO1999043964A1/fr not_active Application Discontinuation
  • 1999-02-15 EP EP99903755A patent/EP0977953A1/fr not_active Withdrawn
  • 1999-02-15 JP JP54321299A patent/JP2002503326A/ja active Pending

Non-Patent Citations (1)

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