GB2117333A

GB2117333A - Bicycle frames

Info

Publication number: GB2117333A
Application number: GB08208813A
Authority: GB
Inventors: Patrick O'brien
Original assignee: Tekton
Current assignee: Tekton
Priority date: 1982-03-25
Filing date: 1982-03-25
Publication date: 1983-10-12

Abstract

The frame is in the form of a bifurcated assembly adapted to be disposed diagonally between the rear wheel (10) of the vehicle and the handle-bars. The assembly is adapted to grip a seat supporting element (7) and the steering head seat (8) and to define a fork for the reception of the rear wheels (10). The assembly may be formed from a single metal sheet, two metal half shells, cast or pressed metal or plastics material. <IMAGE>

Description

SPECIFICATION Bicycle frames This invention relates to bicycle and like frames.

The conventional bicycle frame is often described as a diamond frame and this type of frame has been in use for a period approaching a hundred years. The diamond frame is now relatively expensive to produce considering the nature of the parts involved and an object of the present invention is the provision of a basic frame arrangement which the applicant believes will at least minimize the above disadvantage.

According to the present invention such a frame includes a bifurcated assembly adapted to be disposed between the rear wheel of the vehicle and the handle-bars thereof, the assembly being adapted to grip a seat supporting element and the steering head set, with the assembly defining a fork for the reception of the rear wheel.

In a preferred form of a bicycle frame according to the invention, a single metal sheet is employed to form the bifurcated assembly.

In an alternative frame arrangement according to the invention, two parts from separate metal sheets are employed to define the bifurcated assembly, the parts being mirror images of one another.

Preferably the bifurcated assembly is disposed diagonally between the rear wheel of the vehicle and the handle-bars thereof.

In one form of the invention the parts are formed in a pressing, casting or moulding operation and are clamped together in operative position with suitable clamping means. The material used in the formation of the frame parts is a matter of choice; generally metal being preferred although the use of suitable synthetic resinous material, fibreglass or the like, or combination of such materials is not precluded.

It is anticipated that after the frame of the invention has been provided, conventional bicycle components may thereafter be used in the construction of the finished vehicle.

To illustrate the invention an example is described hereunder with reference to the accompanying drawings in which:- Figure 1 is a perspective view with parts broken away and parts in ghost line of one form of bicycle using one embodiment of the new frame; Figure 2 is a plan view of the frame of Figure 1; Figure 3 is a side view showing the lie of the frame of Figure 1 when wheels are in position thereon: and Figure 4 is a view similar to that of Figure 1 of a presently preferred embodiment of a bicycle frame according to the invention.

Referring particularly to Figure 1 of the drawings, the frame comprises two mirror image parts 4 and 5 which are clamped together in any suitable form. In one arrangement the parts 4 and 5 are separate pressings. In a presently preferred embodiment as shown in Figure 4 of the drawings, a single pressing which is bent at the fore-end 6 defines a bifurcated assembly according to the invention.

The two parts shown in Figure 1 and the corresponding parts of the embodiment of Figure 4 act to nip between them the seat tube 7 and the steering head set 8 as illustrated, each of which is of generally conventional form with the pedal structure being attached at region 9 of the seat tube. The rear wheel 10 of the vehicle is located in the fork zone 1 2 provided by the frame.

It is anticipated that the arrangement of the invention will result in the provision of a bicycle of the same or greater strength than that produced using the diamond type frame.

Also, the applicant believes that the frame of the invention will be less expensive in its production. Furthermore, the general appearance of a bicycle made in accordance with the invention should be of a pleasing and modern nature.

By providing the frame parts with large apertures such as those shown by the references 11, 12 and 13 in Figures 1 and 3 substantial reduction in the overall weight of the vehicle may be obtained.

Clamping of the parts 4 and 5 of the embodiment of Figures 1 to 3 may be achieved satisfactorily by passing suitable bolts through receiving orifices in the frame. For instance, in the vicinity of reference 14 a suitable number of clamping bolts may be located. It will be noted that the seat tube and the steering head set are accommodated in apertures defined by the mating frame parts. These apertures are shown merely in diagrammatic form and may, and probably will, in fact comprise specially formed bearing tubes which contact the seat tube over a fairly substantial area to prevent undue point loading on the structural elements.

It will be understood that substantially the same principles apply to the presently preferred embodiment illustrated in Figure 4 save that the bifurcated assembly comprises a single frame part. Thus, the rear wheel of the vehicle is received in suitable slots 1 6 provided in each part of the bifurcated assembly forming a fork 1 8. The seat tube 7 may be secured to the bifurcated assembly through any convenient means such as welding or clamping by means of bolts and the like. Also the head set 8 may be secured to the frame by means of bolts 20 in suitable apertures provided in the fore-end 6 of the frame.

Many more examples of the invention exist each differing from one another merely in detail.

1. A bicycle frame including a bifurcated assembly adapted to be disposed between the rear wheel of the vehicle and the handle-bars thereof, the assembly being adapted to grip a seat supporting element and the steering head set, the assembly defining a fork for the reception of the rear wheel.

2. The frame of Claim 1 in which a single metal sheet is employed to form the bifurcated assembly.

3. The frame of either Claim 1 or Claim 2 in

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Bicycle frames This invention relates to bicycle and like frames. The conventional bicycle frame is often described as a diamond frame and this type of frame has been in use for a period approaching a hundred years. The diamond frame is now relatively expensive to produce considering the nature of the parts involved and an object of the present invention is the provision of a basic frame arrangement which the applicant believes will at least minimize the above disadvantage. According to the present invention such a frame includes a bifurcated assembly adapted to be disposed between the rear wheel of the vehicle and the handle-bars thereof, the assembly being adapted to grip a seat supporting element and the steering head set, with the assembly defining a fork for the reception of the rear wheel. In a preferred form of a bicycle frame according to the invention, a single metal sheet is employed to form the bifurcated assembly. In an alternative frame arrangement according to the invention, two parts from separate metal sheets are employed to define the bifurcated assembly, the parts being mirror images of one another. Preferably the bifurcated assembly is disposed diagonally between the rear wheel of the vehicle and the handle-bars thereof. In one form of the invention the parts are formed in a pressing, casting or moulding operation and are clamped together in operative position with suitable clamping means. The material used in the formation of the frame parts is a matter of choice; generally metal being preferred although the use of suitable synthetic resinous material, fibreglass or the like, or combination of such materials is not precluded. It is anticipated that after the frame of the invention has been provided, conventional bicycle components may thereafter be used in the construction of the finished vehicle. To illustrate the invention an example is described hereunder with reference to the accompanying drawings in which:- Figure 1 is a perspective view with parts broken away and parts in ghost line of one form of bicycle using one embodiment of the new frame; Figure 2 is a plan view of the frame of Figure 1; Figure 3 is a side view showing the lie of the frame of Figure 1 when wheels are in position thereon: and Figure 4 is a view similar to that of Figure 1 of a presently preferred embodiment of a bicycle frame according to the invention. Referring particularly to Figure 1 of the drawings, the frame comprises two mirror image parts 4 and 5 which are clamped together in any suitable form. In one arrangement the parts 4 and 5 are separate pressings. In a presently preferred embodiment as shown in Figure 4 of the drawings, a single pressing which is bent at the fore-end 6 defines a bifurcated assembly according to the invention. The two parts shown in Figure 1 and the corresponding parts of the embodiment of Figure 4 act to nip between them the seat tube 7 and the steering head set 8 as illustrated, each of which is of generally conventional form with the pedal structure being attached at region 9 of the seat tube. The rear wheel 10 of the vehicle is located in the fork zone 1 2 provided by the frame. It is anticipated that the arrangement of the invention will result in the provision of a bicycle of the same or greater strength than that produced using the diamond type frame. Also, the applicant believes that the frame of the invention will be less expensive in its production. Furthermore, the general appearance of a bicycle made in accordance with the invention should be of a pleasing and modern nature. By providing the frame parts with large apertures such as those shown by the references 11, 12 and 13 in Figures 1 and 3 substantial reduction in the overall weight of the vehicle may be obtained. Clamping of the parts 4 and 5 of the embodiment of Figures 1 to 3 may be achieved satisfactorily by passing suitable bolts through receiving orifices in the frame. For instance, in the vicinity of reference 14 a suitable number of clamping bolts may be located. It will be noted that the seat tube and the steering head set are accommodated in apertures defined by the mating frame parts. These apertures are shown merely in diagrammatic form and may, and probably will, in fact comprise specially formed bearing tubes which contact the seat tube over a fairly substantial area to prevent undue point loading on the structural elements. It will be understood that substantially the same principles apply to the presently preferred embodiment illustrated in Figure 4 save that the bifurcated assembly comprises a single frame part. Thus, the rear wheel of the vehicle is received in suitable slots 1 6 provided in each part of the bifurcated assembly forming a fork 1 8. The seat tube 7 may be secured to the bifurcated assembly through any convenient means such as welding or clamping by means of bolts and the like. Also the head set 8 may be secured to the frame by means of bolts 20 in suitable apertures provided in the fore-end 6 of the frame. Many more examples of the invention exist each differing from one another merely in detail. CLAIMS

3. The frame of either Claim 1 or Claim 2 in which two parts from separate metal sheets are employed to define the bifurcated assembly, the parts being mirror images of one another.

4. The frame of Claim 3 in which the parts are clamped together in operative association through the agency of suitable clamping means.

5. The frame of any one of the above claims in which the bifurcated assembly is formed in a pressing operation.

6. The frame of any one of Claims 1 to 4 above in which the bifurcated assembly is formed in a casting operation.

7. The frame of either Claim 5 or Claim 6 in which the assembly is formed from metal.

8. The frame of any one of Claims 1 to 4 which the bifurcated assembly is formed from a synthetic resinous material, fibreglass or the like.

9. The frame of Claim 8 in which the assembly is formed in a moulding operation.

1 0. The frame of any one of the above claims in which the bifurcated assembly is adapted to be disposed diagonally between the rear wheel of the vehicle and the handle-bars thereof.

11. A bicycle frame substantially as herein described and as illustrated with reference to the accompanying drawings.