GB2357242A - Castor with brake means retained by the wheel - Google Patents

Castor with brake means retained by the wheel Download PDF

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Publication number
GB2357242A
GB2357242A GB9929558A GB9929558A GB2357242A GB 2357242 A GB2357242 A GB 2357242A GB 9929558 A GB9929558 A GB 9929558A GB 9929558 A GB9929558 A GB 9929558A GB 2357242 A GB2357242 A GB 2357242A
Authority
GB
United Kingdom
Prior art keywords
wheel
castor
brake means
engaging portion
formations
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.)
Granted
Application number
GB9929558A
Other versions
GB9929558D0 (en
GB2357242B (en
Inventor
Kelvin Anthony John Daniels
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.)
Guy Raymond Engineering Co Ltd
Original Assignee
Guy Raymond Engineering Co Ltd
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 Guy Raymond Engineering Co Ltd filed Critical Guy Raymond Engineering Co Ltd
Priority to GB9929558A priority Critical patent/GB2357242B/en
Publication of GB9929558D0 publication Critical patent/GB9929558D0/en
Publication of GB2357242A publication Critical patent/GB2357242A/en
Application granted granted Critical
Publication of GB2357242B publication Critical patent/GB2357242B/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/0028—Construction of wheels; methods of assembling on axle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/0036—Castors in general; Anti-clogging castors characterised by type of wheels
    • B60B33/0042—Double or twin wheels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/0047—Castors in general; Anti-clogging castors characterised by details of the rolling axle
    • B60B33/0049—Castors in general; Anti-clogging castors characterised by details of the rolling axle the rolling axle being horizontal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/0047—Castors in general; Anti-clogging castors characterised by details of the rolling axle
    • B60B33/0057—Castors in general; Anti-clogging castors characterised by details of the rolling axle the rolling axle being offset from swivel axis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/006—Castors in general; Anti-clogging castors characterised by details of the swivel mechanism
    • B60B33/0065—Castors in general; Anti-clogging castors characterised by details of the swivel mechanism characterised by details of the swivel axis
    • B60B33/0068—Castors in general; Anti-clogging castors characterised by details of the swivel mechanism characterised by details of the swivel axis the swivel axis being vertical
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/006—Castors in general; Anti-clogging castors characterised by details of the swivel mechanism
    • B60B33/0065—Castors in general; Anti-clogging castors characterised by details of the swivel mechanism characterised by details of the swivel axis
    • B60B33/0073—Castors in general; Anti-clogging castors characterised by details of the swivel mechanism characterised by details of the swivel axis the swivel axis being symmetrical to wheel or wheels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/0078—Castors in general; Anti-clogging castors characterised by details of the wheel braking mechanism
    • B60B33/0086—Castors in general; Anti-clogging castors characterised by details of the wheel braking mechanism acting on rim or side portion of tyre
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B33/00—Castors in general; Anti-clogging castors
    • B60B33/02—Castors in general; Anti-clogging castors with disengageable swivel action, i.e. comprising a swivel locking mechanism
    • B60B33/021—Castors in general; Anti-clogging castors with disengageable swivel action, i.e. comprising a swivel locking mechanism combined with braking of castor wheel

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Braking Arrangements (AREA)

Abstract

A castor 10 comprises: a body 12; a first wheel 14 rotatably mounted to the body 12; and a brake member 16 mounted to the body 12 for operation between a first position for preventing rotation of the wheel 14 relative to the body 12 and a second position for allowing rotation; wherein when mounted to the body 12 the wheel 14 retains the brake member 16 mounted for the said operation. A second wheel 18 is rotatably mounted to the body 12 and, in the first position, the brake member 16 prevents rotation of the second wheel 18 and, in the second position, the brake member 16 allows rotation. The first wheel 14 and the second wheel 18 are independently rotatably relative to the body 12 and are mounted to opposite sides of the body 12. The body 12 comprises an end portion having a bore 20 for receiving a metal stem (not shown) which extends from the bore for mounting the castor 10 to a piece of furniture.

Description

2357242 Castor The invention relates to a castor and to a method of
assembling a castor.
Castors are known hereto and a castor having a brake is known from the Applicant's GB 2306106A. In that patent, a castor is disclosed which comprises a body, two wheels and a brake member which is operable to prevent rotation of the wheels. Assembly of the disclosed castor is hampered by the way in which the brake member is mounted in the castor and does not easily submit to automated assembly or mass production methods.
It Is an object of the invention to solve or at least mitlaate the abovementioned problem.
To this end, the present invention provides a castor comprising: a body; a wheel rotatably mountable to said body; and brake member mountable to said body for operation between a first position for preventing rotation of said wheel relative to said body and a second position for allowing said rotation; wherein when mounted to said body said wheel retains said brake member mounted for said operation.
It is preferred that when mounted to said body said wheel retains said brake member mounted for said operation by engagement of a surface of said wheel against a corresponding surface of said brake member and engagement of a surface of said body against a corresponding surface of said brake member.
2 Said brake member may be pivotally mounted to said body.
Preferably, said brake member is pivotal in response to a torque applied to an operating portion thereof which extends externally of said body. -In a preferred arrangement, said brake member comprises a spigot which is received in a corresponding bore in said body and about which said brake member is pivotal between said first position and said second position.
Advantageously, said wheel comprises a plurality of uniformly circumferentially spaced apart formations and said brake member comprises an engaging portion; and in said first position, said engaging portion is engaged with at least one of said forniations and, in said second position, said engaging portion is disengaged from said formations.
More advantageously, said engaging portion is capable of interlocking with a said formation of said wheel and engaging with portions of an adjacent pair of said formations and whether in said first position the engaging portion interlocks with a said formation or engages with portions of an adjacent pair of said formations depends upon the rotational position of said wheel relative to said body.
Still more advantageously, said formations are projections extending radially to an axis of rotation of said wheel and said engaging portion comprises a generally W-shaped cross-section.
3 Preferably, said brake member comprises a snap finger cooperable with a pin on said body to prevent pivotal movement of said brake member If said torque is below a predetermined value.
More preferably, if said torque is above the predetermined value, the brake member is caused to snap between said first position and the second position.
In a preferred arrangement, the castor further comprises a second wheel rotatably mounted to said body and wherein, in said first position, said brake member prevents rotation of said wheels relative to said body and in said second position, said brake member allows said rotation.
In a more preferred arrangement, when the brake member is in said first position said engaging portion engages with an at least one said formation on said second wheel to prevent rotation of said second wheel relative to said body and in said second position said engaging portion is disengaged from said formations on said second wheel to allow rotation of said second wheel relative to said body.
Said wheels may be independently rotatable relative to said body.
Preferably, said engaging portion is capable of interlocking with a said formation of said second wheel and engaging with portions of an adjacent pair of said formations of said second wheel and whether in said first position the engaging portion interlocks with a said formation of said second wheel or engages with portions of an adjacent pair of said formations of said second 4 wheel depends upon the rotational position of said second wheel relative to said body.
The present invention also provides a method of assembling a castor having a brake member, comprising the steps of. inserting a spigot of said brake member into a bore of a castor body and mounting a wheel to said body thereby retaining said brake member in an operable condition wherein in a first position of said brake member said wheel is prevented from rotating relative to said body and in a second position of said brake member said wheel is allowed to rotate relative to said body.
In order that the present invention may be well understood, an embodiment thereof which is given by way of example only will now be described with reference to the accompanying drawings, in which:
Figure 1 is a side view of a castor; Figure 2 is a top view of the castor of Figure 1; Figure 3 is a bottom view of the castor of Figure 1; Figure 4 is a rear view of the castor of Figure 1; Figure 5 is a ftont view of the castor of Figure 1; Figure 6 is a perspective view of a brake member which is a part of the castor of Figure 1; Figure 7 is a side view of the brake member taken in the direction indicated by arrow A shown in Figure 6; Figure 8 is a side view of a body which is a part of the castor shown in Figure 1; Figure 9 is a view of a shaft which is part of the castor shown in Figure 1; Figure 10 is a side view of a wheel which is a part of the castor shown in Figure 1; Figure 11 is a cross-sectional view taken along line B-B shown in Figure 8; Figure 12 is a schematic drawing of the brake member mounted to the body with the brake member in a second position; Figure 13 is a schematic drawing of the brake member mounted to the body with the brake member in a first position; and Figures 14 and 15 are schematic drawings showing part of the castor of Figure 1 taken along line C-C in Figure 11 showing a wheel and an engaging portion of the brake member with the brake member in the first position shown in dashed lines.
Referring to Figures 1 to 5, a castor indicated generally at 10 comprises: a body 12; a first wheel 14 rotatably mounted to the body 12; and brake member 16 mounted to the body 12 for operation between a first position for preventing rotation of the wheel 14 relative to the body 12 and a second position for allowing rotation; wherein when mounted to the body 12 the wheel 14 retains the brake member 16 mounted for the said operation.
6 A second wheel 18 is rotatably mounted to the body 12 and, in the first position, the brake member 16 prevents rotation of the second wheel IS and, in the second position, the brake member 16 allows rotation thereof The first wheel 14 and the second wheel 18 are independently rotatably relative to the body 12 and are mounted to opposite sides of the body 12.
The body 12 comprises an end portion having a bore 20 for receiving a metal stem (not shown) which extends from the bore for mounting the castor to a piece of furniture.
The illustrated castor may be classified as low height and high-load as it is especially suitable for mounting to furniture designed to receive heavy loading and where overall height is important for example drawer units which are to be positioned under desk table tops. Appropriate dimensions for the castor are 45mm length by 40mm width by 30mm height although any suitable dimensions may be adopted as required.
The assembled castor and its constituent parts will now be described with reference to Figures 6 to 15. The body 12 (see Figure 8) comprises a central bore 22 into which a shaft 24 extends (see Figure 9). A strengthening nm 26 supports a central portion of the shaft 24. The body 12 is further strengthened by a radially extending nb 28. The wheels 14, 18 are mounted on respective end portions of the shaft 24 for rotation about. a longitudinal axis of the shaft 24. The wheels 14, 18 rotate relative to the shaft 24 to permit each wheel to rotate independently relative to the body 12.
7 Each wheel is configured as shown in Figures 10 and 11, and has a blind bore 30 for receiving an end portion of the shaft 24. A circumferential ridge 32 in each blind bore 30 engages with a complementary circumferential groove 34 at an end portion of the shaft 24 to mount the wheel securely to the shaft 24. Each wheel is strengthened by radially extending ribs 36.
A spigot 38 of the brake member 16 is received for pivotal movement in a bore 40 of the body 12. Figures 12 and 13 show schematically the brake member 16 mounted to the body 12 but the shaft 24 and wheels 14,18 are not shown for simplicity. The brake member 16 is pivotal between a first position (shown in Figure 13) in which an engaging portion 42 engages with at least one of a plurality of uniformly spaced apart formations 44 on the wheels 14, 18 to prevent rotation of the wheels relative to the body 12 and a second position (shown in Figure 12) in which the engaging portion 42 is disengaged from formations 44 on the wheels to allow the wheels to rotate relative to the body.
The method of engagement between the brake member and the wheels will be described with reference to Figures 14 and 15 in which wheel 14 is shown in engagement with the engaging portion 42 - the brake member is shown in dashed lines in the first position with the shaft 24 and the body 12 not shown for simplicity. Engagement with wheel 18 works in the same way and therefore -will not be specifically described. The engaging portion 42 is 8 capable of interlocking with a forination 44 of wheel 14 (as shown in Figure 15) and engaging with portions of an adjacent pair of the forinations 44 (as shown in Figure 14) and whether, in the first position, the engaging the portion interlocks with a formation 44 or engages with portions of an adjacent pair of the formations 44 depends upon the rotational position of the wheel relative to the body. Since the rotational position of each wheel relative to the body 12 may be different, the engaging portion 42 can, for instance, interlock with a fori-nation 44 of the first wheel 14 and at the same time engage portions of an adjacent pair of formations 44 on the second wheel 18.
The engaging portion 42 comprises two sections 46, 46 with a W shaped cross-section as shown in Figure 6. The inner faces of sections 46, 46 are for interlocking with a formation 44 and the outer faces of sections 46, 46 are for engaging portions of a pair of adjacent fon-nations 44. The formations are projections extending radially outwardly from a hub 48 of a wheel but equally could extend radially inwardly from a rim 50 of a wheel.
Referring to Figures 6, 7, 12 and 13, the brake member 16 comprises a snap finger 52 cooperable with a pin 54 extending axially from the body 12 to prevent pivotal movement of the brake member 16 if the torque applied to the brake member 16 about the spigot 38 (shown in dashed lines in Figures 12 and 13) is below a predetermined value. A torque above the predetennined value causes the brake member 16 to snap between the first position (shown in 9 Figure 13) and the second position (shown in Figure 12) so that the engaging portion 42 is either engaged with at least one formation 44 or disengaged from the formations 44. This substantially prevents partial engagement and reduces the chance of the brake member 16 being pivoted accidentally.
The spigot 38 is retained in the bore 40 when the first wheel 14 is mounted to the shaft 24. This is achieved by the brake member 16 being engaged between respective surfaces of the first wheel 14 and the body 12.
Specifically in the embodiment, an axially inwardly facing surface 56 of hub 48 of the first wheel 14 engages axially outwardly facing surface 58 of the brake member 16. The strengthening rim 26 of the body has an axially inwardly stepped portion having an axially outwardly facing surface 60 which engages an axially inwardly facing surface 62 of the brake member 16. The engagement of these surfaces locates the brake member 16 correctly for operation between the first position and the second position.
The brake member 16 comprises an operating portion 64 which extends externally of the body 12 as shown in Figures 1 to 4. When the castor is assembled and mounted to a piece of furniture a torque is applied to the operating portion 64 to operate the brake member 16. Ridges 66 are provided on upwardly facing surface of the operating portion to improve grip.
Assembly of the illustrated castor is performed by inserting shaft 24 into bore 22 of body 12. Spigot 38 of brake member 16 is inserted into bore of body 12 with the brake member in its second position (Fig. 12) until outwardly facing surface 60 engages inwardly facing surface 62 of the brake member. Each end portion of the shaft is inserted into the blind bore 30 of respective wheels 14,18 which causes the axially inwardly facing surface 56 of first wheel 14 to engage axially outwardly facing surface 58 of brake member 16 thereby retaining the brake member in position for operation.
It will be appreciated therefore that assembly of the illustrated castor comprising the body 12, shaft 24, brake member 16 and two wheels 14, 18 is simple and easily lends itself to mass production techniques and automated assembly, not least because each of the constituent parts of the castor can be assembled in the same direction, ie in an axial direction.

Claims (1)

  1. CLAIMS:
    1. A castor comprising: a body; a wheel rotatably mountable to said body; and brake means mountable to said body for operation between a first position for preventing rotation of said wheel relative to said body and a second position for allowing said rotation; wherein when mounted to said body said wheel retains said brake means mounted for said operation.
    2. A castor as claimed in claim 1 wherein when mounted to said body said wheel retains said brake means mounted for said operation by engagement of a surface of said wheel against a corresponding surface of said brake means and engagement of a surface of said body against a corresponding surface of said brake means.
    3. A castor as claimed in claim 1 or 2 wherein said brake means is pivotally mounted to said body.
    4. A castor as claimed in claim 3 wherein said brake means is pivotal in response to a torque applied to an operating portion thereof which extends externally of said body.
    12 5. A castor as claimed in any one of the preceding claims wherein said brake means comprises a spigot which is received in a corresponding bore in id body and about which said brake me 1 sai ans is pivotal between said first position and said second position.
    6. A castor as claimed in any one of the preceding claims wherein said wheel comprises a plurality of uniformly circumferentially spaced apart formations and said brake means comprises an engaging portion; and wherein, in said first position, said engaging portion is engaged with at least one of said formations and, in said second position, said engaging portion is disengaged ftom said formations.
    7. A castor as claimed in claim 6 wherein said engaging portion is capable of interlocking with a said formation of said wheel and engaging with portions of an adjacent pair of said formations and whether in said first position the engaging portion interlocks with a said formation or engages with portions of an adjacent pair of said formations depends upon the rotational position of said wheel relative to said body.
    8. A castor as claimed in claim 7 wherein said formations are projections extending radially to an axis of rotation of said wheel and said engaging portion comprises a section with a generally W-shaped cross-section.
    13 9. A castor as claimed in any one of claims 4 to 8, wherein said brake means comprises a snap finger cooperable with a pin on said body to prevent pivotal movement of said brake means if said torque is below a predetermined value.
    10. A castor as claimed in claim 9, wherein if said torque is above the predetermined value, the brake means is caused to snap between the first position and the second position.
    11. A castor as claimed in any one of the preceding claims comprising a second wheel rotatably mounted to said body and wherein, in said first position, said brake means prevents rotation of said wheels relative to said body and in said second position, said brake means allows said rotation.
    12. A castor as claimed in claim 11 wherein when the brake means is in said first position said engaging portion engages with at least one formation on said second wheel to prevent rotation of said second wheel relative to said body and in said second position said engaging portion is disengaged from said formations on said second wheel to allow rotation of said second wheel relative to said body.
    14 13. A castor as claimed in claim 11 or 12 wherein said wheels are independently rotatable relative to said body.
    14. A castor as claimed in claim 13 wherein said engaging portion is capable of interlocking with a said formation of said second wheel and engaging with portions of an adjacent pair of said formations of said second wheel and whether in said first position the engaging portion interlocks with a said formation of said second wheel or engages with portions of an adjacent pair of said formations of said second wheel depends upon the rotational position of said second wheel relative to said body.
    15. A castor substantially as hereinbefore described with reference to the accompanying drawings.
    16. A method of assembling a castor having a brake means, comprising the steps of. inserting a spigot of said brake means into a bore of a castor body and mounting a wheel to said body thereby retaining said brake means in an operable condition wherein in a first position of said brake means said wheel is prevented from rotating relative to said body and in a second position of said brake means said wheel is allowed to rotate relative to said body.
    17. A method of assembling a castor having a brake means, said method being substantially as herein described with reference to the accompanying drawings.
GB9929558A 1999-12-14 1999-12-14 Castor Expired - Lifetime GB2357242B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9929558A GB2357242B (en) 1999-12-14 1999-12-14 Castor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB9929558A GB2357242B (en) 1999-12-14 1999-12-14 Castor

Publications (3)

Publication Number Publication Date
GB9929558D0 GB9929558D0 (en) 2000-02-09
GB2357242A true GB2357242A (en) 2001-06-20
GB2357242B GB2357242B (en) 2003-09-10

Family

ID=10866305

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9929558A Expired - Lifetime GB2357242B (en) 1999-12-14 1999-12-14 Castor

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2913201A1 (en) * 2014-02-27 2015-09-02 Steinco Paul vom Stein GmbH Single wheel roller

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2306106A (en) * 1995-10-16 1997-04-30 Guy Raymond Eng Co Ltd Castor wheel

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2306106A (en) * 1995-10-16 1997-04-30 Guy Raymond Eng Co Ltd Castor wheel

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2913201A1 (en) * 2014-02-27 2015-09-02 Steinco Paul vom Stein GmbH Single wheel roller
CN104924848A (en) * 2014-02-27 2015-09-23 施泰因科保罗沃施泰因有限公司 Single wheel caster
CN104924848B (en) * 2014-02-27 2018-03-30 施泰因科保罗沃施泰因有限公司 Single wheel caster

Also Published As

Publication number Publication date
GB9929558D0 (en) 2000-02-09
GB2357242B (en) 2003-09-10

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

Expiry date: 20191213