GB1578349A - Bearing assemblies - Google Patents

Bearing assemblies Download PDF

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Publication number
GB1578349A
GB1578349A GB37572/76A GB3757276A GB1578349A GB 1578349 A GB1578349 A GB 1578349A GB 37572/76 A GB37572/76 A GB 37572/76A GB 3757276 A GB3757276 A GB 3757276A GB 1578349 A GB1578349 A GB 1578349A
Authority
GB
United Kingdom
Prior art keywords
roller
bearing assembly
plastics
race member
assembly
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB37572/76A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BRIDGE BEARINGS
Original Assignee
BRIDGE BEARINGS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BRIDGE BEARINGS filed Critical BRIDGE BEARINGS
Priority to GB37572/76A priority Critical patent/GB1578349A/en
Priority to SE7709836A priority patent/SE7709836L/en
Priority to DE19772740302 priority patent/DE2740302A1/en
Priority to FR7727344A priority patent/FR2364171A1/en
Publication of GB1578349A publication Critical patent/GB1578349A/en
Expired legal-status Critical Current

Links

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
    • F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
    • F16C35/04—Rigid support of bearing units; Housings, e.g. caps, covers in the case of ball or roller bearings
    • F16C35/06—Mounting or dismounting of ball or roller bearings; Fixing them onto shaft or in housing
    • F16C35/067—Fixing them in a housing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
    • B65G39/00—Rollers, e.g. drive rollers, or arrangements thereof incorporated in roller-ways or other types of mechanical conveyors 
    • B65G39/02—Adaptations of individual rollers and supports therefor
    • B65G39/09—Arrangements of bearing or sealing 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
    • F16C13/00—Rolls, drums, discs, or the like; Bearings or mountings therefor
    • F16C13/02—Bearings
    • F16C13/022—Bearings supporting a hollow roll mantle rotating with respect to a yoke or axle
    • 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
    • F16C27/00—Elastic or yielding bearings or bearing supports, for exclusively rotary movement
    • F16C27/06—Elastic or yielding bearings or bearing supports, for exclusively rotary movement by means of parts of rubber or like materials
    • F16C27/066—Ball or roller bearings
    • 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
    • F16C33/58—Raceways; Race rings
    • F16C33/60—Raceways; Race rings divided or split, e.g. comprising two juxtaposed rings
    • 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
    • F16C2326/00—Articles relating to transporting
    • F16C2326/58—Conveyor systems, e.g. rollers or bearings therefor

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Rollers For Roller Conveyors For Transfer (AREA)
  • Rolls And Other Rotary Bodies (AREA)

Description

(54) BEARING ASSEMBLIES (71) We, BRIDGE BEARINGS LIMITED, a British Company of Stour Vale Road, Lye, Stourbridge, West Midlands, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : This invention relates to a conveyer roller assembly which comprises a tubular roller member having at each end a bearing assembly with inner and outer race members and a plurality of rolling elements, e.g. balls or rollers, operative between the inner and outer race members, providing for support of the roller assembly on stub axles or a spindle carried between conveyor side rails. Such a conveyor roller assembly will hereafter be referred to as a conveyor roller assembly of the kind specified.
It is an object of the present invention to provide an improved form of conveyor roller assembly.
According to the present invention, we provide a conveyor roller assembly of the kind specified wherein the outer race member of each bearing assembly includes a plastics portion and a hardened metal insert which provides a surface which contacts the rolling elements, the outer race member being at least partially received within the tubular roller member and an end portion of the latter being deformed inwardly from an initial condition to retain the bearing assembly in position and also to deform the plastics portion of the outer race member in a manner to retain the metal insert therein.
Such an assembly presents an advantage in that it is relatively cheap to manufacture since only a small portion of the outer race member, i.e. the part actually contacted by the rolling elements, is required to withstand high loads and be made of metal, whilst the remainder of the outer race member is of plastics which can be produced relatively economically as a moulding. Further, the arrangement whereby the plastics portion is deformed by deformation of the tubular roller member, to retain the bearing assembly in position relative to the roller member and the hardened metal insert in the plastics portion by virtue of friction forces therebetween, gives a high degree of security in service against possible failure and yet permits easy assembly.
The plastics portion of the outer race member may afford a central aperture with a radially inwardly extending flange, the metal insert being received in such aperture and being further retained therein by a locking member which has snap engagement in the aperture, the deformation of the tubular roller member preventing the plastics portion from undergoing expansion which would be necessary in order to permit the locking member to be removed from the aperture.
The plastics portion of the outer race member may include radially inner and outer portions defining between them, prior to deformation, an axially extending annular groove, the groove being closed as a result of the deformation.
The effect of this construction is that the plastics portion of the outer race member incorporates a relatively small quantity of plastics material, thereby rendering manufacture more economical compared with a solid plastics portion which would be required to be present if the plastics portion were not deformed to form the final assembly.
In other words, the strength of the assembly is derived from the deformation of the tubular roller member and plastics outer race portion rather than from the provision of a large mass of material.
The invention also provides a bearing assembly as set forth above for a conveyor roller assembly of the kind specified.
These and other features of the invention will be apparent from the following description with reference to the accompanying drawing, which is a radial section through one end of a conveyor roller with a bearing assembly according to the invention, two stages in manufacture of the assembly being illustrated.
Referring to the drawing, there is shown one end of a conveyor roller assembly comprising a tubular roller member 1 with two bearing assemblies 4 one in each end of the roller, the roller assembly being mounted between two conveyor side rails 2 on a spindle 3. Each bearing assembly comprises an inner metal race member 5 and an outer race member 6 which consist of an outer plastics portion 7 and an inner hardened metal insert 8.
The insert 8 is of annular form and has an L-shaped cross-section, with a radially inwardly extending limb 16. The insert is retained in a central aperture 9 in the outer race member 6 between a radially inwardly extending flange 10 and a separate plastics locking member 11. The locking member 11 is retained in position by an annular lip 1 la on the locking member which snaps into a cdrresponding groove 13 in the outer plastics portion 7.
A plurality of steel balls 12 are disposed between the inner race member 5 and the outer race member 6. The balls run in a groove 18 cut into the inner race member 5 which is hardened in order to resist indentation by the balls. The balls thus run between hardened metal surfaces provided on the inner and outer race members respectively.
The outer plastics portion 7 of the bearing assembly has, initially, a cross section of generally Z shape, with radially inner and outer parts which define between them, on the side of the bearing assembly open to the exterior of the assembly, an axially extending annular groove 7a. A further groove 7b is defined on the side of the assembly facing the interior of the roller member 1. A lip 7c on the outer edge of the portion 7 limits the extent to which the outer race is entered into the roller member 1.
Oil seal members 17 are press-fitted on the inner race member 5 on each side of the bearing assembly for preventing egress of lubricant therefrom and ingress of dirt.
Each bearing assembly is retained in the end of the roller member 1 by deforming the respective end portion la slightly radially inwardly to adopt the configuration shown in the lower part of the drawing. This deforms the outer part of portion 7 inwardly to close the groove 7a, which in turn prevents release of the insert 8 from the central aperture 9 and prevents the inner part of the plastics portion 7 from expanding to release the locking member 11 from its snap engagement therein.
The retention of the bearing assembly in the roller member 1 thus also retains the insert in its position in the bearing assembly.
The inner race member 5 of each bearing assembly is provided with a portion 14 which projects axially beyond the outer race member 6. The bearing assemblies are secured in the ends of the conveyor roller in a back to back configuration so that the portions 14 of the two assemblies project outwardly from the ends of the roller, i.e. the radially extend ing limbs 16 of the metal inserts are towards one another.
Considering the bearing assembly shown in the drawing, if the roller 1 should be displaced in the direction of the arrow A during use sufficiently to cause the portion 14 of the inner race member to contact the adjacent inside surface 15 of the side member 2, further axial displacement of the roller will be resisted by contact between the balls 12 and the radially inwardly extending limb 16 of the insert 8.
If the roller is displaced axially in the direction of the arrow B during use the projecting portion 14 of the other bearing assembly (not shown) will contact the adjacent inside surface of the other side rail again causing the force which has resulted in the axial displacement of the roller to be resisted by the radially inwardly extending limb portion 16 of the other bearing assembly.
Thus should the roller be displaced axially in either direction during use through a sufficient distance to cause either of the portions 14 of the inner race members to contact the side rails, any axial force transmitted through the balls 12 will be reacted against by hardened metal portions of the bearing assembly, thus removing the danger of the balls identing any of the plastics portions of the assemblies.
If desired, the inner race member 5 may itself be of a composite plastics metal construction. For example, the portion of the inner race member contacted by the balls 12 may be hardened metal insert and the inner part of the race member which engages the spindle 3 may be of a plastics construction.
The present invention thus provides an improved form of bearing assembly which is relatively cheap to produce and which is capable of withstanding rasonably high radial and axial loads without the ball or roller members of the bearing assembly indenting the race members.
WHAT WE CLAIM IS: 1. A conveyor roller assembly of the kind specified wherein the outer race member of each bearing assembly includes a plastics portion and a hardened metal insert which provides a surface which contacts the rolling elements, the outer race member being at least partially received within the tubular roller member and an end portion of the latter being deformed inwardly from an initial condition to retain the bearing assembly in position and also to deform the plastics portion of the outer race member in a manner to retain the metal insert therein.
2. An assembly according to Claim 1 wherein the plastics portion of t'le outer race member affords a central aperture having a radially inwardly extending flange, the metal insert is received in such aperture and abuts
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (10)

**WARNING** start of CLMS field may overlap end of DESC **. assemblies 4 one in each end of the roller, the roller assembly being mounted between two conveyor side rails 2 on a spindle 3. Each bearing assembly comprises an inner metal race member 5 and an outer race member 6 which consist of an outer plastics portion 7 and an inner hardened metal insert 8. The insert 8 is of annular form and has an L-shaped cross-section, with a radially inwardly extending limb 16. The insert is retained in a central aperture 9 in the outer race member 6 between a radially inwardly extending flange 10 and a separate plastics locking member 11. The locking member 11 is retained in position by an annular lip 1 la on the locking member which snaps into a cdrresponding groove 13 in the outer plastics portion 7. A plurality of steel balls 12 are disposed between the inner race member 5 and the outer race member 6. The balls run in a groove 18 cut into the inner race member 5 which is hardened in order to resist indentation by the balls. The balls thus run between hardened metal surfaces provided on the inner and outer race members respectively. The outer plastics portion 7 of the bearing assembly has, initially, a cross section of generally Z shape, with radially inner and outer parts which define between them, on the side of the bearing assembly open to the exterior of the assembly, an axially extending annular groove 7a. A further groove 7b is defined on the side of the assembly facing the interior of the roller member 1. A lip 7c on the outer edge of the portion 7 limits the extent to which the outer race is entered into the roller member 1. Oil seal members 17 are press-fitted on the inner race member 5 on each side of the bearing assembly for preventing egress of lubricant therefrom and ingress of dirt. Each bearing assembly is retained in the end of the roller member 1 by deforming the respective end portion la slightly radially inwardly to adopt the configuration shown in the lower part of the drawing. This deforms the outer part of portion 7 inwardly to close the groove 7a, which in turn prevents release of the insert 8 from the central aperture 9 and prevents the inner part of the plastics portion 7 from expanding to release the locking member 11 from its snap engagement therein. The retention of the bearing assembly in the roller member 1 thus also retains the insert in its position in the bearing assembly. The inner race member 5 of each bearing assembly is provided with a portion 14 which projects axially beyond the outer race member 6. The bearing assemblies are secured in the ends of the conveyor roller in a back to back configuration so that the portions 14 of the two assemblies project outwardly from the ends of the roller, i.e. the radially extend ing limbs 16 of the metal inserts are towards one another. Considering the bearing assembly shown in the drawing, if the roller 1 should be displaced in the direction of the arrow A during use sufficiently to cause the portion 14 of the inner race member to contact the adjacent inside surface 15 of the side member 2, further axial displacement of the roller will be resisted by contact between the balls 12 and the radially inwardly extending limb 16 of the insert 8. If the roller is displaced axially in the direction of the arrow B during use the projecting portion 14 of the other bearing assembly (not shown) will contact the adjacent inside surface of the other side rail again causing the force which has resulted in the axial displacement of the roller to be resisted by the radially inwardly extending limb portion 16 of the other bearing assembly. Thus should the roller be displaced axially in either direction during use through a sufficient distance to cause either of the portions 14 of the inner race members to contact the side rails, any axial force transmitted through the balls 12 will be reacted against by hardened metal portions of the bearing assembly, thus removing the danger of the balls identing any of the plastics portions of the assemblies. If desired, the inner race member 5 may itself be of a composite plastics metal construction. For example, the portion of the inner race member contacted by the balls 12 may be hardened metal insert and the inner part of the race member which engages the spindle 3 may be of a plastics construction. The present invention thus provides an improved form of bearing assembly which is relatively cheap to produce and which is capable of withstanding rasonably high radial and axial loads without the ball or roller members of the bearing assembly indenting the race members. WHAT WE CLAIM IS:
1. A conveyor roller assembly of the kind specified wherein the outer race member of each bearing assembly includes a plastics portion and a hardened metal insert which provides a surface which contacts the rolling elements, the outer race member being at least partially received within the tubular roller member and an end portion of the latter being deformed inwardly from an initial condition to retain the bearing assembly in position and also to deform the plastics portion of the outer race member in a manner to retain the metal insert therein.
2. An assembly according to Claim 1 wherein the plastics portion of t'le outer race member affords a central aperture having a radially inwardly extending flange, the metal insert is received in such aperture and abuts
said flange, and the metal insert is further retained therein by a locking member which has snap engagement in said aperture, the deformation of the tubular roller member preventing the plastics portion from expanding to release the locking member.
3. An assembly according to Claim 2 wherein the plastics portion of the outer race member includes radially inner and outer parts defining between them, prior to deformation, an axially extending annular groove, said deformation of the tubular roller member deforming said radially outer part inwardly to close said groove.
4. An assembly according to Claim 2 wherein the metal insert is of L-shaped crosssection having an axially extending limb and a radially inwardly extending limb, said radially inwardly extending limb abutting said flange.
5. An assembly according to Claim 4 wherein the bearing assemblies in the ends of the roller assembly are arranged with said radially extending limbs of the metal inserts towards one another.
6. An assembly according to Claim 2 wherein said locking member is of plastics material.
7. A bearing assembly for a conveyor roller assembly of the kind specified, comprising an inner race member, a plurality of rolling elements, and an outer race member including a plastics portion and a hardened metal insert which provides a surface which contacts the rolling elements, the metal insert being received in a central aperture in the plastics portion of the outer race member, the plastics portion of the outer race member including radially inner and outer parts defining between them an axially extending annular groove and said outer part being inwardly deformable, to close said groove thereby to prevent removal of said metal insert.
8. A bearing assembly according to Claim 7 wherein plastics portion of the outer race member affords the central aperture having a radially inwardly estending flange, the metal insert is received in such aperture and abuts said flange, and the metal insert is further retained therein by a locking member which has snap engagement in said aperture, the deformation of the tubular roller member preventing the plastics portion from expandng to release the locking member.
9. A conveyor roller assembly substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.
10. A bearing assembly substantially as hereinbefore described with reference to and as shown in the accompanying drawing.
GB37572/76A 1976-09-10 1976-09-10 Bearing assemblies Expired GB1578349A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
GB37572/76A GB1578349A (en) 1976-09-10 1976-09-10 Bearing assemblies
SE7709836A SE7709836L (en) 1976-09-10 1977-09-01 ROLLER UNIT FOR A TRANSPORTER
DE19772740302 DE2740302A1 (en) 1976-09-10 1977-09-07 CONVEYOR ROLL
FR7727344A FR2364171A1 (en) 1976-09-10 1977-09-09 CONVEYOR ROLLER PROVIDED WITH ADVANCED BEARINGS

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB37572/76A GB1578349A (en) 1976-09-10 1976-09-10 Bearing assemblies

Publications (1)

Publication Number Publication Date
GB1578349A true GB1578349A (en) 1980-11-05

Family

ID=10397463

Family Applications (1)

Application Number Title Priority Date Filing Date
GB37572/76A Expired GB1578349A (en) 1976-09-10 1976-09-10 Bearing assemblies

Country Status (4)

Country Link
DE (1) DE2740302A1 (en)
FR (1) FR2364171A1 (en)
GB (1) GB1578349A (en)
SE (1) SE7709836L (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2156446A (en) * 1984-03-22 1985-10-09 Rayridge Installations Limited Conveyor roller
EP0278354A2 (en) * 1987-02-06 1988-08-17 Bridge Bearings Limited Bearing assembly
EP0739833A1 (en) * 1995-04-27 1996-10-30 Conveyor Units Limited Conveyors
GB2329370A (en) * 1997-09-20 1999-03-24 John Pyle Securing a circular member to the end of a tubular body

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2050531B (en) * 1979-03-09 1983-07-13 Skf Uk Ltd Conveyor roller
DE3062860D1 (en) * 1979-03-09 1983-06-01 Skf Uk Ltd End cap assemblies for conveyor rollers
EP0015738B1 (en) * 1979-03-09 1984-03-07 Skf (U.K.) Limited Bearing assemblies for conveyor rollers fitted with end covers
US4441601A (en) * 1981-04-20 1984-04-10 C. L. Frost & Son, Inc. Plastic conveyor roller and method of making same
GB2165621B (en) * 1984-10-11 1988-04-07 Skf Svenska Kullagerfab Ab End cap assemblies for conveyor rollers

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2156446A (en) * 1984-03-22 1985-10-09 Rayridge Installations Limited Conveyor roller
EP0278354A2 (en) * 1987-02-06 1988-08-17 Bridge Bearings Limited Bearing assembly
EP0278354A3 (en) * 1987-02-06 1989-05-10 Bridge Bearings Limited Bearing assembly
AU613007B2 (en) * 1987-02-06 1991-07-25 Bridge Bearings Limited Bearing assembly
EP0739833A1 (en) * 1995-04-27 1996-10-30 Conveyor Units Limited Conveyors
US5857554A (en) * 1995-04-27 1999-01-12 Conveyor Units Limited Conveyors
GB2329370A (en) * 1997-09-20 1999-03-24 John Pyle Securing a circular member to the end of a tubular body
GB2329370B (en) * 1997-09-20 2002-04-10 John Pyle A method of securing a bearing housing to the end of a conveyor roller tubular body

Also Published As

Publication number Publication date
DE2740302A1 (en) 1978-03-23
SE7709836L (en) 1978-03-11
FR2364171A1 (en) 1978-04-07

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Legal Events

Date Code Title Description
PS Patent sealed
PE20 Patent expired after termination of 20 years

Effective date: 19970907