A control assembly for a handlebar-steered vehicle with a hydraulic brake

Abstract

A cartridge (15) is inserted into the tube (10) of the handlebar, which cartridge forms a chamber (19) for the piston (16) of the brake master cylinder (13). The cartridge is locked axially along the tube and angularly according to a predetermined angular orientation, by a locking element (40) which is threaded through two opposite through-slots (37, 38) obtained in the tube of the handlebars at a predetermined axial position. The cartridge (15) is axially constrained against the locking element (40), which is received within a recess (33) obtained in the cartridge, having a non-circular shape corresponding to the shape of the locking element, in order to retain the cartridge in position according to the predetermined orientation.

Description

[0001] A control assembly for a handlebar- steered vehicle with a hydraulic brake

[0002] Technical field

[0003] The present invention is in the field of handlebar-steered vehicles equipped with a hydraulic brake. The invention relates to an integrated assembly comprising a tubular handlebar and a control assembly for a hydraulic brake.

[0004] Prior art

[0005] As is known, many bicycles and other handlebar-steered vehicles are equipped with a hydraulic braking system, wherein a brake master cylinder, actuated by a brake control lever mounted on the handlebar, controls a brake caliper associated with each wheel by means of a flexible hydraulic tube. The brake master cylinder and an associated tank containing a reserve of brake fluid are mounted on the handlebar near the control lever. The flexible tube runs externally along the handlebar.

[0006] US 2019 / 0152457 Al discloses a control assembly for a brake or a hydraulic clutch of a handlebar- steered vehicle. A brake master cylinder is arranged inside a handlebar tube; a hydraulic flexible tube is hydraulically connected to the master cylinder and runs inside the handlebar tube. A manual control lever, external to the handlebar, is connected in an articulated manner to a piston in the master cylinder by means of a tie-rod transmission element which exerts a traction force on the piston when the control lever is actuated.

[0007] WO 2023 / 187667 Al discloses a hydraulic brake control assembly for a handlebar- steered vehicle having a handlebar tube containing a brake master cylinder therein. The brake master cylinder comprises an axially elongated cylindrical cartridge, configured to be permanently mounted inside the handlebar tube. The cartridge forms an axially extended chamber inside which a piston is partially accommodated. In order to apply pressure to the brake fluid and actuate a brake of the vehicle, the user pulls a traditional brake lever mounted on the handlebar which moves the piston of the brake master cylinder axially by means of a transmission mechanism using an articulated lever on the handlebar. An adjustment screw is used to adjust the relative longitudinal position of the cartridge with respect to the piston, which adjustment screw engages through a threaded central hole made in a rigid disc that may be fixed inside the handlebar tube near one end thereof. The longitudinal position of the rigid disc inside the handlebar tube is determined by a shoulder inserted into the handlebar tube and provided with peripheral teeth that snap into respective through-openings formed through the handlebar tube. The shoulder acts as a support for the metal disc and has a central through-hole adapted to receive the adjustment screw, the head of which is accessible from the open end of the handlebar tube.

[0008] Summary of the invention

[0009] An object of the invention is to improve the accuracy and stability wherewith the axial position and angular orientation of a brake master cylinder are established inside a handlebar tube.

[0010] These and other objects and advantages, which will be better understood herein after, are achieved, according to the present invention, by a hydraulic brake control assembly having the features set forth in claim 1. Preferred embodiments are defined in the dependent claims.

[0011] In summary, a cartridge is inserted into the handlebar tube which forms a chamber for the piston of the brake master cylinder; the cartridge is locked axially along the tube and angularly, according to a predetermined angular orientation, by means of a locking element which is inserted through two opposite through-slots obtained in the handlebar tube at a predetermined axial position. The cartridge is axially constrained against the locking element, which is accommodated in a recess formed in the cartridge, having a non-circular shape corresponding at least partially to the shape of the locking element, in order to retain the cartridge in position according to the predetermined orientation.

[0012] Brief description of the drawings

[0013] A few preferred but non-limiting embodiments of a hydraulic brake control assembly according to the invention will now be described, with reference to the accompanying drawings, wherein:

[0014] Figure 1 is an axial sectional view of a hydraulic brake control assembly integrated in a handlebar tube of a handlebar- steered vehicle, with a manual control lever;

[0015] Figure 2 is a top view of the assembly of Figure 1;

[0016] Figure 3 is a cross-sectional view according to the line III-III of Figure 2;

[0017] Figure 4 is a perspective view of a cartridge which composes the assembly of Figure 1 ; and

[0018] Figure 5 is a side view according to the arrow V in Figure 2.

[0019] Detailed description

[0020] Referring to the figures, a control assembly for a hydraulic brake of a handlebar- steered vehicle, in particular (but not exclusively) a bicycle, is integrated into a handlebar tube 10, and more particularly into a straight end portion of the handlebar tube 10.

[0021] The handlebar tube 10 forms an inner cavity 11 having an inner cylindrical surface 12 which defines a central axis x herein referred to as “longitudinal” and has an open end 14.

[0022] Throughout the present description and in the appended claims, terms indicating orientations and directions such as “longitudinal”, “transversal”, “outer” and “inner” are to be interpreted with reference to the longitudinal axis x, unless otherwise noted.

[0023] The control assembly comprises a brake master cylinder 13 adapted to apply pressure to a braking fluid in order to actuate at least one brake (not shown) of the vehicle.

[0024] The brake master cylinder 13 is mounted within the cavity 11 of the handlebar tube and comprises a cartridge 15 and a piston 16.

[0025] As shown in the example of Figure 4, the cartridge 15 has a variously shaped form with a side surface 17 forming part of an axially elongated cylindrical surface, configured to be mounted in a fixed manner in the inner cavity 11 of the handlebar tube 10. The cartridge 15 may be made of a plastics material or else of a metal material such as aluminum or the alloys thereof.

[0026] The cartridge 15 is shaped such as to form at least one axially extended inner chamber 18 wherein the piston 16 is accommodated in an axially slidable manner. The cartridge 15 may also form channels therein to allow the brake fluid pressurized by the piston 16 to be sent through a delivery port (not shown) and tubing (not shown) to at least one brake of the vehicle, typically a brake caliper.

[0027] The cartridge 15 forms an end portion 19 having a transversal end face 20 that faces, in the assembled condition (Figure 1), towards the open end 14 of the handlebar tube 10.

[0028] The specific shape of the cartridge 15, with the exception of the shape of the end portion 19 thereof, as described below, is not in itself relevant to the understanding and implementation of the present invention and is therefore not described in detail herein.

[0029] For the manufacture of those parts and elements of the brake control assembly that are not shown in detail here, reference may be made, for example, to WO 2023 / 187667 Al. It will suffice here to indicate that the piston 16 of the brake master cylinder is actuated by pulling a traditional control lever 22 mounted on the handlebar tube 10. The control lever, by means of a transmission mechanism 23, which in this example comprises a rocker arm lever 24 and a connecting rod 25, biases the piston 16 along the chamber 18, against a compression spring 26 interposed between the piston 16 and the bottom of the chamber 18. A delivery port (not shown) is formed at a bottom end of the chamber 18 facing in use towards the open end 14 of the handlebar tube (on the left in Figure 1). The thrust imparted by piston 16 partially releases part of the brake fluid contained within the chamber 18 from the delivery port. The brake fluid then follows a path through a channel (not shown) obtained in the body of the cartridge 15 and is then sent to a brake of the vehicle through a flexible tube (not shown).

[0030] In the condition (Figure 1) wherein the cartridge 15 is mounted in the handlebar tube 10, the end portion 19 of the cartridge, which in this example is cylindrical in shape, is spaced apart from the free and open end 14 of the handlebar tube.

[0031] In the present example, when observed in an axial direction, the end face 20 of the cartridge is circular in shape.

[0032] A non-circular-shaped recess or axial imprint 21 is obtained in the end face 20 that extends diametrically from a first peripheral portion 27 (or circumferential arc) of the end face 20, to a second opposite peripheral portion or opposite arc 28, passing through the central axis x which passes through the center of the end face 20.

[0033] In the example shown in the drawings, the axial recess 21 is delimited by two pairs of parallel sides 29, 30 and 31, 32, which define a transversally wider recess portion 33 and a transversally narrower recess portion 34.

[0034] The axial recess 21 also extends to the center of the end face 20, where a threaded axial central hole 35 is obtained.

[0035] Two slots 37, 38 passing diametrically opposite to the central axis x are obtained in the tube 10 of the handlebar in the same transversal plane perpendicular to the longitudinal axis x: a first slot 37, in this example, circumferentially or transversally more extended, and a second slot 38, circumferentially or transversally less extended than the first.

[0036] Preferably, the two opposite slots 37, 38 have the same axial width.

[0037] The slots 37, 38 are formed in the handlebar tube 10 of the handlebar at a predetermined axial position, because they serve as an axial reference and seats to accommodate a transversal locking element 40, preferably a transversal locking plate which, once inserted into the handlebar tube, serves as a transversal wall for the axial adjustment and locking of the cartridge and also as a reference and lock of the angular orientation of the cartridge about the central axis x.

[0038] The transversal locking element 40 has a central through-hole 41, axially aligned with the threaded axial central hole 35 of the cartridge, and having a diameter not less than the diameter of the threaded hole 35.

[0039] The transversal locking element 40 is inserted into the tube 10 of the handlebar through the larger slot 37, to form a transversal wall with a shoulder or axial stop function for the end face 20 of the cartridge.

[0040] Preferably, the transversal locking element 40 has two diametrically opposite arched edges 27, 28 which, in the condition in which the transversal locking element is inserted into the handlebar tube 10 (Figure 3), do not protrude significantly transversally from the tube 10 of the handlebars and, in the illustrated embodiment, are arranged aligned with the outer cylindrical surface of the handlebar tube.

[0041] According to a preferred embodiment, the axial recess 33 has an axial depth corresponding to the axial thickness of the transversal locking element 40.

[0042] Once the cartridge 12, and thus the transversal locking element 40, has been inserted into the tube 10 of the handlebar, a locking screw 42 is inserted into the threaded hole 35 of the cartridge through the through-hole 41 of the transversal locking element, and the locking screw 42 is tightened, with the result that the cartridge is pulled axially against the transversal locking element 40 thereby abutting axially thereagainst.

[0043] The (at least partially) corresponding non-circular shape of the axial recess 33 and of the transversal locking element 40 unequivocally determines and precisely and stably establishes the angular orientation of the cartridge 15 with respect to the central axis x. This accurately ensures the exact angular position of the chamber 19 that receives the piston 16 of the brake master cylinder. The exact axial position of the cartridge 15 along the handlebar tube 10 is ensured by the tightening of the screw 42.

[0044] While specific embodiments of the invention have been described, it is to be understood that this disclosure has been provided for illustrative purposes only and that the invention is not to be limited in any way thereby. Various modifications will be evident to those skilled in the art in light of the preceding examples. The scope of the invention is limited only by the appended claims.

Claims

CLAIMS1. A control assembly for a handlebar- steered vehicle with a hydraulic brake, comprising: a handlebar tube (10) with an inner cavity (11) having an inner cylindrical surface (12) defining a longitudinal central axis (x), and an open end (14); two through-slots (37, 38) formed in the handlebar tube (10) at diametrically opposite positions with respect to the central axis (x) and lying in a same transversal plane, perpendicular to the central axis (x), a brake master cylinder (13) mounted in the inner cavity of the handlebar tube, wherein the master cylinder comprises a cartridge (15) having an axially elongated overall shape with an at least partially cylindrical outer surface (17) accommodated in the inner cavity (11) of the handlebar tube, wherein the cartridge forms therein at least one axially elongated chamber (19) wherein a plunger (16) of the brake master cylinder is slidingly accommodated, and wherein the cartridge forms an end portion (19) having a transversal end face (20) facing the open end (14) of the handlebar tube, an axial recess (33) having a non-circular shape being formed in the end face (20), wherein the axial recess extends from a first peripheral portion (27) of the end face to a second peripheral portion (28) of the end face opposite the first peripheral portion, a transversal locking element (40) inserted in the handlebar tube (10) and having two opposing peripheral portions inserted respectively into the two through-slots (37, 38) of the handlebar tube (10), wherein the transversal locking element (40) is resting against the end face (20) of the cartridge and is at least partially accommodated within the axial recess (33) and has a non-circular shape at least partially corresponding to the non-circular shape of the axial recess (33), at least one fastening element (42) for axially locking the cartridge against the transversal locking element (40) at a predetermined axial position along the tube (10) of the handlebar and according to a predetermined angular orientation with respect to the central axis (x).

2. A control assembly according to claim 1, whereina threaded hole (35) is obtained in the end face (20) and extends along the central axis (x) or parallel thereto, a central through-hole (41) is formed in the transversal locking element (40) axially aligned with the threaded hole (35) of the cartridge; the clamping element (42) is a threaded element inserted through the through-hole (41) of the transversal locking element (40) and screwed into the threaded hole (35) of the cartridge to tighten the cartridge (15) against the transversal locking element (40) at a predetermined axial position along the tube (10) of the handlebar and according to a predetermined angular orientation with respect to the central axis (x).

3. A control assembly according to claims 1 or 2, wherein the axial recess (33) extends from the first peripheral portion (27) of the end face to the second peripheral portion (28) of the end face opposite the first peripheral portion, extending across the central axis (x).

4. A control assembly according to any one of the claims from 1 to 3, wherein a first slot (37) of the two slots (37, 38) is circumferentially or transversally longer than a second slot (38) circumferentially or transversally less extended than the first slot.

5. A control assembly according to any one of the preceding claims, wherein the two opposite slots (37, 38) have a same axial width, the transversal locking element (40) being a plate element having a uniform axial thickness corresponding to the axial width of the two slots (37, 38).

6. A control assembly according to any one of the preceding claims, wherein the transversal locking element (40) has two diametrically opposite arched edges (27, 28) which do not protrude in a transversal direction from an outer cylindrical surface of the handlebar tube (10).

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