GB2158890A

GB2158890A - Pedal bearing for bicycles

Info

Publication number: GB2158890A
Application number: GB08418470A
Authority: GB
Inventors: Alfred Heinrich Thun
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-05-18
Filing date: 1984-07-19
Publication date: 1985-11-20
Also published as: DE3418499C1; GB8418470D0; FR2564539B1; FR2564539A1; IT1174050B; IN164399B; JPS60244686A; IT8421826A1; IT8421826A0

Abstract

Pedal bearing for bicycles comprises a tubular housing (2,3) which is detachably insertable into the pedal bearing frame bushing (1) and penetrated by a pedal crankshaft (4) provided with two shoulders (11), of which the mutually facing flanks are constructed as inner bearing races. The housing is composed of two housing parts (2,3) screwed together coaxially and mounted in the frame bushing, and each is provided with a coaxially integrally formed outer bearing race for rolling-contact elements (13). The arrangement is such that the internal diameter of the housing (2,3) is greater than the diameter of the shoulders (11), with this arrangement the housing parts may be assembled on the crank shaft (4) with only one pedal removed. Removable covers (17) close the space between the end of the housing and the crank shaft. <IMAGE>

Description

SPECIFICATION Pedal bearing for bicycles The invention starts from a pedal bearing for bicycles of the type stated in the pre-characterising clause of Claim 1 and known from German Utility Design 8305001.

This known pedal bearing consists of a housing detachably insertable intothe pedal bearing frame bushing,which is penetrated by a pedal crankshaft which exhibits two shoulders constructed on the mutually remote flanks as races for rolling-contact elements and arranged at a mutual interval within the housing, which are confronted by races for rolling-contact elements arranged in the housing.Rotatable rolling-contact elements are inserted between the races, whilst the races for rolling-contact elements belonging to the housing are of axially adjustable and lockable construction in order to adjust the bearing play, and whilst the housing is composed of two substantially pot-shaped housing parts with their orifices mutually facing and mutually coaxially screwable, of which the ends penetrated by the pedal shaft exhibit races for rolling-contact elements integrally moulded coaxially on the inside.

However, this configuration dictates that both pedals must be attached detachably to the crankshaft in order to permit the housing parts to be plugged onto the crankshaft.

The aim of the invention is to improve by simple means, a pedal bearing of the type stated in the pre-characterising clause of Claim 1, so that it is also applicable to those pedal bearings in which only one pedal is attached detachably to the crankshaft in each case, whereas the other pedal forms an indissoluble entity with the crankshaft, in order to simplify and cheapen both production and assembly.

This aim is achieved by the following characteristic features: a. the mutually facing flanks of the shoulders arranged on the crankshaft are constructed as inner races for rolling-contact elements; b. the two housing parts are of tubular construction, their smallest inside width is greater than the crankshaft shoulders, and the outer races for rolling-contact elements are respectively arranged on the free end faces of the housing parts which are screwed together, and c. covers closing the annular space bounded by the crankshaft and by the frame bushing are plugged onto the crankshaft.

Due to these measures it is now possible for both the housing parts, screwed together, to be plugged conjointly onto the crankshaft over a free shaft end part, so that it is no longer necessary to attach both pedals detachably to the crankshaft.

At the same time it is also ensured that, after the insertion of the rolling-contact elements between the races for the later, the respective desired rolling-contact bearing play can be adjusted and optionally also readjusted by means of the housing parts screwed together. Adequate sealing of the pedal bearing against spray water is also achieved.It is advantageous, in order to further reduce production costs, if the housing parts of small wall thickness, which exhibit annular crosssections along their total length, each have on their mutually remote end parts an integrally shaped zone widening in diameter towards the free end, the insides of which are constructed as outer races for rolling-contact elements, whilst the housing parts can be produced cheaply from tubular sections and whilst the above-mentioned zones widened in diameter should be formed by widening a tubular end part in each case.

In order to achieve the arrangement of the above-described pedal bearing securely and in the correct position in the frame bushing by simple means, an outwardly oriented flange braced in the axial direction against the adjacent end face of the frame bushing is arranged, particularly integrally shaped, on a housing part adjacent to the zone widened in inside diameter and constructed as an outer race for rolling-contact elements, and the above-mentioned widened zones of the housing parts are constructed for application without play to the inside of the frame bushing.

For this purpose it is further advantageous if the zones widened in inside diameter of the housing parts are of cylindrical construction at their circumference.

A particularly simple and nevertheless functionally reliable configuration of the covers consists in that the one first cover has an angled rim enclosing the frame bushing,but the other second cover exhibits a tubular section engaging into the frame bushing and maintained at least frictionally, which further encloses without play the adjacent housing part zone widened in inside diameter and furthermore an outwardly oriented flange, which is braced against the adjacent end face of the frame bushing, is provided on the second cover.

In this case the first cover should be applied by its outer end face to a sprocket wheel arranged integrally in rotation on the crankshaft for fixation in the axial direction.

In order to exclude any accidental twisting of the housing parts screwed together, a check nut may be associated with their screw connection.

A preferred variant of the above, which further simplifies the assembly, consists in that a ring of resiliently yielding material of high coefficient of friction, particularly of plastics, the bore of which is at least approximately aligned coaxially with the screwth readed bore and the inside diameter of which is smaller than the outside diameter of the male screwthreaded zone arranged on the other housing part and engaging frictionally into the ring, is inserted firmly into the housing part which is adjacent to the sprocket wheel in the screwing-in direction of the other housing part adjacent to a screwthreaded bore.

Due to these measures the housing parts screwed together are secured against accidental twisting, without the necessity for a check nut.

A further development of the above which is favourable for production consists in that the above-mentioned ring is of polyhedral external construction and is plugged nonrotatably into a polyhedral zone of the housing part adapted thereto.

Yet another advantageous further development of the above is characterised in that spanner grips, particularly in the form of slots, are provided in the free end face, remote from the sprocket wheel, of the one housing part.

These measures make it possible to correct the rolling-contact bearing play by twisting the other housing part by means of a tool adapted to the slots, even after the insertion of the pedal bearing into the frame bushing, when the housing part adjacent to the sprocket wheel is secured at least frictionally against twisting in the frame bushing.

In order to further simplify and reduce the cost of production, it is advantageous if the one housing part which is adjacent to the sprocket wheel and carries the ring serving as untwisting arrester is constructed as a deepdrawn part and exhibits a shorter axial length than the other housing part, whilst furthermore the axial lengths of the one housing part adjacent to the sprocket wheel and of the other housing part should preferably be the proportion of approximately 1:4.

In order to improve further the secure positioning of the pedal bearing inserted into the frame bushing, it is advantageous if the zone, widening in diameter towards the free end, of the housing part remote from the sprocket wheel is constructed to extend beyond the adjacent end face of the frame bushing and beyond the cover arranged on the free end of the crankshaft and exhibits a male screwthreaded zone onto which a screw nut is screwed which is tensioned, indirectly through the cover, onto the end face, adjacent to the latter, of the frame bushing.

In this case a ring seal enclosing and tightly sealing the crankshaft may be arranged, particularly integrally moulded, on the screw nut.

A variant of the above, which may possibly be preferred, consists in that a ring seal enclosing and tightly sealing the crankshaft, engaging and tightly sealing into the adjacent widened housing part zone, and maintained frictionally, is provided on the end part of the crankshaft remote from the sprocket wheel.

Exemplary embodiments of the invention are illustrated in the drawing and described more fully below. In the drawing: Figure 1 shows a pedal bearing in longitudinal section; Figure 2 shows a variant of the above, likewise in longitudinal section; and Figure 3 shows details of a further embodiment, only partly illustrated.

In all the embodiments, a housing composed of two tubular housing parts 2 and 3 which is inserted detachably into a frame bushing 1 of a bicycle frame, is penetrated by a pedal crankshaft 4 which has a pedal 5 attached non-detachably at the one end. A sprocket wheel 6 is further mounted integrally in rotation on the crankshaft 4. The other end part of the crankshaft 4 is constructed, in manner known per se, for the arrangement, integrally in rotation and detachably, of a further pedal, not shown.

The housing part 2 has on the end part facing the housing part 3 a screwthreaded bore 7, whilst a male screwthreaded zone 8 adapted to the screwthreaded bore 7 is arranged on the end part of the housing part 3 facing the housing part 2. This zone 8 is screwed into the screwthreaded bore 7. This adjustable screw connection is intended, in the exemplary embodiment illustrated in Fig.

1, to be secured against accidental release by means of a known element, by means of a check nut for example.

On each of the two relatively thin-walled tubular housing parts 2 and 3 of annular cross-section, on the mutually remote end parts of the housing in each case, a zone 9 widening in inside diameter towards the free end is integrally moulded, the insides of which are constructed as outer races 10 for rolling-contact elements. The zones 9 are of cylindrical external construction.

The crankshaft 4 also has two shoulders 11 arranged at a mutual interval in the axial direction, the mutually facing flanks of which are constructed as inner races 1 2 for rollingcontact elements. Rolling-contact elements 13 constructed as balls are inserted between the races 10 and 1 2 for the same.

A radially outwards oriented flange 14, which abuts the adjacent end face of the frame bushing 1, is integrally shaped on the zone 9 of the housing part 2.

The zone 9 of the housing part 2 is moreover dimensioned externally so that it abuts the frame bushing 1 internally without play.

Two covers 1 5 and 1 6 plugged onto the crankshaft 4 are also provided. The cover 1 5 has an integrally shaped angled rim 1 7 enclosing the frame bushing 1 and forming a labyrinth seal with the latter, and is braced against the sprocket wheel 6 in the axial direction by its outer end face.

A tubular section 1 8 engaging into the frame bushing 1 and abutting without play both the inside of the frame bushing 1 and the outside of the zone 9 of the housing part 3 is integrally shaped, particularly from plastics, on the cover 1 6. The cover 1 6 also has an integrally shaped flange 1 9 abutting the end face, adjacent to itself, of the frame bushing 1.

The production of the housing parts 2 and 3 is preferably effected from cylindrical tubular sections, on which the zones 9 are integrally shaped by widening the tubular section end parts. The races 10 and 1 2 for rollingcontact elements have hardened surfaces.

In order to assemble the pedal bearing,the two housing parts 2 and 3 are first of all screwed together, and are then likewise plugged onto the crankshaft 4 after the cover 1 5 has been plugged onto the crankshaft 4, and the rolling-contact elements 1 3 are then introduced between the races 10 and 1 2 for the latter. For this purpose the housing parts 2 and 3 are initially screwed towards each other so far that sufficiently large spaces are produced between the zones 9 and the shoulders 11 to enable the rolling-contact elements to be introduced through them between the races 10 and 12.

After this the housing parts 2 and 3 are screwed apart until the required rolling-contact bearing play is obtained.

Following this, this assembly unit only requires to be plugged into the frame bushing 1, and the cover 16 to be added.

In the case of the pedal bearings illustrated in Figs. 2 and 3, the zone 9 of the housing part 3 is constructed to extend beyond the free end face of the frame bushing 1, and has a male screwthreaded zone 20 onto which a screw nut 21 is detachably screwed, which is tensioned frictionally through the intermediary of the cover 1 6 onto the free end face of the frame bushing 1.

A ring 22 of plastics, which is arranged coaxially with the screwthreaded bore 7 and exhibits a cylindrical bore smaller compared to the nominal diameter of the male screwthreaded zone 8, is also inserted firmly into the housing part 2 beside the screwthreaded bore 7. The free end part of the housing part 3, which exhibits the male screwthreaded zone 8, is screwed frictionally into this bore of the ring 22, whilst the screw lands of the male screwthreaded zone 9 resiliently displace corresponding zones in the ring 22 and thus secure the housing parts,when screwed together, against accidental twisting. For the non-rotatable arrangement of the ring 22, the latter is of polyhedral external construction and plugged frictionally from the zone 9 into a correspondingly polyhedrally profiled zone of the housing part 2.In the case of this development it is advantageous, from rational considerations, to produce the housing part 3 by deep drawing from a round,whilst the housing part 3 should exhibit the shortest possible axial length in order to keep the waste for producing the round as low as possible.

Furthermore, circumferentially arranged spanner grips in the form of polyhedra may be integrally shaped on both housing parts between the zones 9, whilst in the case of the housing part 2 previously described, this external polyhedron should be arranged in the region of the inserted ring 22.

In order to seal also the rolling-contact bearing remote from the sprocket wheel 6 in the case of the pedal bearing shown in Fig. 2, a ring seal 23 plugged onto and tightly sealing the crankshaft 4, plugged into and tightly sealing the zones 9 of the housing part 3, and frictionally maintained is provided.

According to Fig. 3 a ring seal 23' enclosing and tightly sealing the crankshaft 4 is integrally shaped on the screw nut 21, whilst the screw nut 21 together with the ring seal 23 may be produced from plastics, to enable an annular flexible sealing lip to be integrally shaped on the ring seal 23'.

The ring seal 23' could also be prefabricated and attached to the screw nut 21, although this would result in longer assembly times.

The invention is also applicable to pedal bearings in which both pedals are attached detachably to the crankshaft 4.

It is also possible to prefabricate the shoulders 11 of the crankshaft 4 and to anchor them on the crankshaft.

The frame bushing 1 has an inside diameter of 34 mm, which is current international practice. The externally cylindrical zone 9 of the housing part 2 is adapted between outside diameter to the inside diameter of the frame bushing 1 so that this zone 9 can be plugged into the frame bushing 1 as a tight fit, whereas the remaining region of the housing 2, and the housing part 3 including its zone 9 are constructed so much smaller in diameter than the inside diameter of the frame bushing 1 that an electric line for a rear light laid in the frame tubes of a bicycle and passed through the frame bushing neither obstructs the introduction into the frame bushing 1 of the pedal bearing arranged on the crank axis, nor leads to damage to the above-mentioned electric line.

The above-described pedal bearing can moreover be inserted into the frame bushing in the correct position even if the frame tubes attached to the frame bushing protrude slightly into the frame bushing, so that the difficult and onerous elimination of the frame tube residues projecting into the frame bushing which is otherwise necessary can be eliminated.

The above-described pedal bearing furthermore permits a careful adjustment of the bearing play and a functional control before installation into the frame bushing, a possible readjustment of the bearing play after the running-in of the pedal bearing, without the need to detach the pedal bearing out of the frame bushing, and, before the installation of the pedal bearing, the control of the frame bushing inter alia for possible residues of paint and/or solder and a simple elimination thereof, because the above-described pedal bearing requires only relatively short cylindrical bearing zones in the end regions of the frame bushing for its installation in the correct position.

Claims

1. Pedal bearing for bicycles, comprising a housing detachably insertable into the pedal bearing frame bushing of a bicycle, and penetrated by a pedal crankshaft provided with two integrally shaped shoulders constructed as inner races for rolling-contact elements and arranged at a mutual axial interval within the housing,wherein the inner races are confronted by outer races for rolling-contact elements arranged in the housing, and between which races rotatable rolling-contact elements are arranged; the housing comprising two mutually coaxially screwable housing parts retained in the frame bushing, which each exhibit a coaxially integrally shaped outer race for rolling-contact elements, characterised by the following features: a) The mutually facing flanks of the shoulders arranged on the crankshaft are constructed as inner races for rolling-contact elements; b) the two housing parts are of tubular construction; their smallest inside diameter being greater than the diameter of the crankshaft shoulders, and the outer races for rolling-contact elements being respectively arranged on the free end faces of the housing parts which are screwed together, and c) covers closing the annular space bounded by the crankshaft and by the frame bushing are plugged onto the crankshaft.

2. Pedal bearing according to Claim 1 characterised in that the housing parts (2 + 3) of small wall thickness, which exhibit annular cross-sections along their total length, each have at their mutually remote end parts an integrally shaped zone (9) widening in inside diameter towards the free end, the insides of which are constructed as outer races (10) for rolling-contact elements.

3. Pedal bearing according to Claim 2, characterised in that an outwardly oriented flange (14) braced in the axial direction against the adjacent end face of the frame bushing (1) is arranged, particularly integrally shaped, on a housing part (2) adjacent to the zone (9) widened in inside width and constructed as an outer race (10) for rollingcontact elements.

4. Pedal bearing according to any of the previous Claims, characterised in that the zones (9) of the housing parts (2 + 3) which are widened in inside diameter are of cylindrical construction at their circumference.

5. Pedal bearing according to any of the previous Claims, characerised in that the one first cover (15) has an angled rim (17) enclosing the frame bushing (1).

6. Pedal bearing according to any of the previous Claims, characterised in that the other second cover (16) exhibits a tubular section (18) engaging into the frame bushing (1) and retained at least frictionally, which further encloses without play the adjacent housing part zone (9) widening in inside diameter and that moreover an outwardly oriented flange (16), which is braced against the adjacent end face of the the frame bushing, is provided on the second cover (16).

7. Pedal bearing according to any of the previous Claims, characterised in that the first cover (15) is aplied by its outer end face to a sprocket wheel (6) arranged on the crankshaft (4).

8. Pedal bearing according to any of the previous Claims, characterised in that a ring (22) of resiliently yielding material with a high coefficient of friction, particularly of plastics, the bore of which is at least approximately coaxially aligned with a screwthreaded bore (7), and the inside width of which is smaller than the outside diameter of the male screwthreaded zone (8) arranged on the other housing part (3) and engaging frictionally in the ring, is inserted firmly into the housing part (2) which is adjacent to the sprocket wheel (6) in the screwing-in direction of the other housing part (3) next to the screwthreaded bore (7).

9. Pedal bearing according to Claim 8, characterised in that the above-mentioned ring (22) is of externally polyhedral construction and is plugged non-rotatably into a polyhedral zone of the housing part (2) adapted thereto.

10. Pedal bearing according to any of the previous Claims, characterised in that spanner grips, particularly in the form of slots, are provided in the free end face, remote from the sprocket wheel (6) of the one housing part (3).

11. Pedal bearing according to any of the previous Claims, characterised in that the one housing part (2) which is adjacent to the sprocket wheel (6) and carries the ring (22) serving as an untwisting arrester, is constructed as a deep-drawn part and exhibits a shorter axial length than the other housing part (3).

1 2. Pedal bearing according to Claim 11, characterised in that the axial lengths of the one housing part (2) adjacent to the sprocket wheel (6) and of the other housing part (3) are in the proportion of approximately 1:4.

1 3. Pedal bearing according to any of the previous Claims, characterised in that the zone (9) widening in diameter towards the free end of the housing part (3) remote from the sprocket wheel (6) is constructed to extend beyond the adjacent end face of the frame bushing (1) and beyond the cover (16) arranged on the free end of the crankshaft (4) and exhibits a male screwthreaded zone (20) onto which a screw nut (21) is screwed which is tensioned indirectly through the cover (16) onto the end face of the frame bushing (1) adjacent to the latter.

1 4. Pedal bearing according to Claim 13, characterised in that a ring seal (23') enclosing and tightly sealing the crankshaft (4) is arranged, particularly integrally shaped, on the screw nut (21).

1 5. Pedal bearing according to any of the previous Claims, characterised in that a ring seal (23) enclosing and tightly sealing the crankshaft (4) and engaging into and tightly sealing in the adjacent widened housing part zone (9) and retained by friction is provided on the end part, remote from the sprocket wheel (6), of the crankshaft (4).

1 6. A pedal bearing for a bicycle substantially as described herein with reference to the accompanying drawings.