Bicycle handlebar assembly with integrated oleo-hydraulic controls

Abstract

The bicycle handlebar assembly comprises a handlebar rod and at least one oleo-hydraulic group for controlling on-board bicycle equipment; the oleo-hydraulic group is housed inside the handlebar rod. The internal housing in the handlebar rod overcomes any problems of bulk of the oleo-hydraulic group. Moreover, thanks to the relatively large size of the handlebar rod, the dimensional constraints imposed on the designer are much less stringent with respect to controls associated directly to the brake lever; it is thus relatively easy to make controls capable of exerting very large forces.

Claims

1. Bicycle handlebar assembly, comprising: a handlebar rod that defines an outer surface and an inner cavity defining an inner surface; a hydraulic brake actuated by pressurised fluid; a brake control with a brake lever, a brake cable constrained at a first end thereof to the brake lever, a control lever constrained to the brake cable at a second end thereof, and a pin between the control lever and the handlebar rod; at least one hydraulic assembly that controls the hydraulic brake and includes a fluid containing cylinder that is structurally unitized with the inner surface, and a piston slidable in the fluid containing cylinder, wherein the piston is constrained to the control lever, so as to be actuated to compress fluid in the fluid containing cylinder following actuation of the brake lever, thereby providing the pressurised fluid to the hydraulic brake; wherein the fluid containing cylinder is provided with two parallel ears in which two holes are formed; and the handlebar rod comprises two holes at positions corresponding to the holes in the ears of the fluid containing cylinder, the pin being in engagement in both (i) the holes in the ears and (ii) the holes in the handlebar rod, and the pin provides both: (i) anchoring between the fluid containing cylinder and the handlebar rod, and (ii) hinging of the control lever to both the handlebar rod and the fluid containing cylinder.

2. Assembly according to claim 1, wherein the fluid containing cylinder comprises a hydraulic fluid passage at an opening in the handlebar rod.

3. Assembly according to claim 1, wherein the piston is hinged to the control lever in an intermediate position between the pin and the attachment position of the brake cable.

4. Assembly according to claim 3, comprising a control adjustment device between the control lever and the piston.

5. Assembly according to claim 4, wherein the control adjustment device comprises a threaded shank, mounted on the piston and in screwing engagement in a threaded seat formed in a cylinder rotatably mounted on the control lever.

6. Assembly according to claim 1, comprising a cable adjustment device between the brake cable and the control lever.

7. A method of making a bicycle handlebar assembly, the method comprising: providing a handlebar rod that defines an inner cavity; providing a brake control including a control lever; providing a hydraulic assembly that controls on-board bicycle equipment and includes a fluid containing cylinder; providing a pin between the control lever and the handlebar rod; and co-moulding the fluid containing cylinder and the handlebar rod to form a unitized structure where the pin is both (i) anchoring the fluid containing cylinder with the handlebar rod, and (ii) hinging the control lever to both the handlebar rod and the fluid containing cylinder.

8. The method according to claim 7, wherein the fluid containing cylinder includes a hydraulic fluid passage at an opening in the handlebar rod.

9. The method according to claim 7, wherein the on-board equipment is a hydraulic brake, actuated by pressurised fluid pushed by the hydraulic assembly; wherein the brake control includes a brake lever and a brake cable, constrained at a first end thereof to the brake lever, and the control lever is constrained to the brake cable at a second end thereof; wherein the hydraulic assembly comprises a piston able to slide in the fluid containing cylinder; and the piston is constrained to the control lever, so as to be actuated to compress fluid in the fluid containing cylinder following actuation of the brake lever.

10. The method according to claim 9, wherein the piston is hinged to the control lever in an intermediate position between the pin and the attachment position of the brake cable.

11. The method according to claim 10, wherein a control adjustment device is arranged between the control lever and the piston.

12. The method according to claim 11, wherein the control adjustment device comprises a threaded shank, mounted on the piston and in screwing engagement in a threaded seat formed in a cylinder rotatably mounted on the control lever.

13. The method according to claim 9, wherein the fluid containing cylinder is provided with two parallel ears, in which two holes are formed for the engagement of the pin.

14. The method according to claim 13, wherein the handlebar rod comprises two holes at the holes in the ears of the fluid containing cylinder, the pin is in engagement both in the holes in the ears and in the holes in the handlebar rod.

15. The method according to claim 9, comprising a cable adjustment device between the brake cable and the control lever.

Description

BRIEF DESCRIPTION OF THE DRAWING(S)

(1) Further characteristics and advantages of the invention will become clearer from the following description of a preferred embodiment thereof, made with reference to the attached drawings. In such drawings:

(2) FIG. 1 is a perspective view of part of a bicycle, with a handlebar assembly according to the invention;

(3) FIG. 2 is a perspective view of the handlebar assembly of the bicycle of FIG. 1;

(4) FIG. 3 is a view of a detail of the handlebar assembly of FIG. 2, with parts partially removed or separated;

(5) FIG. 4 is a view of the detail of FIG. 3, assembled and with parts partially removed;

(6) FIG. 5 is a view of the detail of FIG. 4, seen from a different angle;

(7) FIG. 6 is a view of the detail of FIG. 4, without parts removed;

(8) FIG. 7 is a section view of the handlebar assembly of FIG. 2, taken according to the line VII-VII of FIG. 5;

(9) FIG. 8 is a view of a detail of the handlebar assembly of FIG. 2, with parts partially removed or separated;

(10) FIG. 9 is a section view of the detail of FIG. 8, taken according to the line IX-IX of FIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

(11) In the figures, reference numeral 1 wholly indicates a high-performance bicycle, of which in FIG. 1 it is possible to see at least partially a frame 2, a fork 3 and a front wheel 4. The bicycle 1 is provided with disc brakes 5, the front brake of which can be seen in the figures.

(12) The fork 3 has a handlebar assembly 10 mounted on it, in accordance with the invention. The handlebar assembly 10 comprises a handlebar rod 11 provided at its two ends with respective handgrips 12, for example of the curved type as shown in the figures.

(13) The handlebar rod 11 is preferably made hollow from composite material, obtained by moulding from a matrix of polymeric material in which structural fibres (for example carbon fibres or similar) are included.

(14) In the handlebar rod 11, in a central area thereof, two oleo-hydraulic groups are housed, both indicated with 30, each for controlling one of the two brakes of the bicycle 1. The oleo-hydraulic groups 30 are housed inside the handlebar rod 11.

(15) Each oleo-hydraulic group 30 comprises a cylinder 31, fixedly housed in the handlebar rod 11, and preferably co-moulded in it, as well as a piston 32, sealably sliding in the cylinder 31 and mounted on a stem 33. The co-moulding of the cylinder 31 in the handlebar rod 11 promotes their stable attachment together, so that the cylinder 31 itself participates in the structural strength of the handlebar rod 11, to the extent that the latter can be sized thinner, indeed taking into account the strength contribution given by the cylinder 31.

(16) The cylinder 31 comprises an oil-filling passage 34, provided at an opening 13 in the handlebar rod 11; the passage 34 is removably closed by a threaded cap 35, accessible and removable through the opening 13. In the cylinder 31 there is a fluid, in particular oil (not shown in the figures) intended to be placed under pressure as will be illustrated hereafter. The cylinder 31 is provided with an outlet mouth 36, to which a tube 37 is connected that takes pressurised fluid to one of the brakes 5, where the pressurised fluid is used to control a brake caliper on a brake disc, in a per se known way, not illustrated.

(17) The handlebar assembly 10 at the handgrips 12 comprises respective brake controls 14, with a brake lever 15, a control lever 16 and a brake cable 17. The control lever 16 is hinged to the handlebar rod 11 through a pin 18, near to an end of the control lever 16 itself. The brake cable 17 is constrained at a first end thereof to the brake lever 15 (in a per se conventional way, not visible in the figures) and at a second end thereof to the control lever 16, through a cable clamp 19.

(18) The stem 33 of the piston 32 is constrained to the control lever 16, so as to be actuated to compress the fluid in the cylinder 31 following actuation of the brake lever 15. The piston 32 is hinged to the control lever 16 in an intermediate position between the pin 18 and the attachment position of the brake cable 17.

(19) The cylinder 31 is provided with two substantially parallel ears 38, in which two respective holes 39 are formed for the engagement of the pin 18. At the holes 39, the handlebar rod 11 comprises two holes 20. The pin 18 is in engagement both in the holes 39 in the ears 38, and in the holes 20 in the handlebar rod 11, so that on the one hand the mechanical action of the control lever 16 with respect to the cylinder 31 is direct and safe, thanks to the hinging of the lever 16 directly to the cylinder 31, and on the other hand the pin 18 contributes to anchoring the cylinder 31 to the handlebar rod 11.

(20) The handlebar assembly 10 also comprises a control adjustment device 41 between the control lever 16 and the piston 32. The control adjustment device 41 comprises a threaded shank 42, mounted on the pin 33 of the piston 32 and in screwing engagement in a threaded seat 43 formed in a cylinder 44, which is rotatably mounted on the control lever 16. A ring nut 45 is fixedly mounted on the stem 33 near to the shank 42, to facilitate its actuation in rotation.

(21) Each brake control 14 also comprises a cable adjustment device 47 between the brake cable 17 and the control lever 16. For example, the device 47 comprisesin a per se known way, not illustrated in detaila pair of facing ring nuts 48 and 49, having angular sectors of different axial thickness, so that the axial thickness of the assembly of the pair of ring nuts 48 and 49 varies based on the reciprocal angular position of the two ring nuts themselves; a washer 50 is provided on which to rest the end 51 of the sheath 52 of the brake cable 17.

(22) The operation of the handlebar assembly 10 can be clearly seen from the above description. In case of braking, the cyclist actuates the brake lever 15 in the normal fashion and in this way induces a traction on the brake cable 17, with respect to the sheath 52. The brake cable 17 then moves the control lever 16 angularly around the pin 18 that thus pushes the piston 32 in the cylinder 31. The result is that the fluid in the cylinder 31 is put under pressure and the pressure in transferred from the tube 37 to the brake caliper 5, obtaining braking.

(23) It is clear that the force with which the brake caliper 5 is brought together depends on the pressure of the fluid, which in turn depends not only on the force exerted by the cyclist on the brake lever 15, but also and particularly on the relationships between the lever arms on the control lever 16 and on the section of the piston 32 and of the cylinder 31. In particular, thanks to the housing of the cylinder 31 in the handlebar rod 11, the section of the cylinder 31 can be relatively large, so as to ensure proportionally high pressures of the fluid, without this resulting in inconvenient bulks.