Hydraulic brake integrated control unit for handlebar-guided vehicle

Abstract

The invention discloses a hydraulic brake integrated control unit for a handlebar-guided vehicle. A hydraulic brake control unit for a handlebar lead vehicle includes a cartridge (12), a piston (14) and a transfer bar (17). The cartridge (12) is mounted in a handlebar tube (10) of a vehicle and forms an inner longitudinal cavity (13) having a port (16) at one end. A piston (14) is stored in the longitudinal bore (13). The transmission rod (17) is pivotally mounted on the handlebar tube body (10). The transmission rod (17) acts between the brake control rod (11) and the piston (14) by exerting a thrust on the brake control rod (11) and the piston (14) in a first longitudinal direction towards the port (16). A passage (18) is formed in the cartridge (12), by means of a port (16) fluidly connecting the longitudinal bore (13) and a hydraulic hose (20), determining a U-shaped path for use with the brake fluid, thereby applying a pressure to the brake fluid contained in the hydraulic hose in a second longitudinal direction opposite the first longitudinal direction.

Description

Technical Field

[0001] The present invention relates to the field of handlebar-guided vehicles equipped with hydraulic brakes. The present invention relates to an integrated control unit for the hydraulic brakes of handlebar-guided vehicles. Also particularly, but not exclusively, the control unit is applied to bicycles. Background Art

[0002] As is known, many bicycles and other handlebar-driven vehicles are equipped with a hydraulic brake system in which a brake master cylinder actuated by a brake control lever on the handlebar controls the brake calipers associated with each wheel via hydraulic hoses. The brake master cylinder and associated reservoir (a storage tank containing brake fluid) are mounted on the handlebar close to the control lever. The hose runs externally along the handlebar.

[0003] US2019 / 0152457 A1 discloses a control unit for a hydraulic brake or clutch of a handlebar-driven vehicle. A brake master cylinder is arranged inside a handlebar tube; a hydraulic hose is hydraulically connected to the master cylinder and runs inside the handlebar tube. A hand lever outside the handlebar is pivotally connected to a piston in the master cylinder via a tie rod drive element, and the tie rod drive element exerts a thrust on the piston when the control lever is actuated. Summary of the invention

[0004] The present invention provides a master cylinder control unit integrated into a handlebar of a vehicle equipped with a hydraulic brake system, wherein a brake fluid hose runs within a handlebar tube.

[0005] The object of the invention is to provide a control unit which is compact, reliable in operation, simple to install in the handlebar tube and which preferably gives the possibility of adjusting the brake load curve in different braking phases according to requirements.

[0006] According to the present invention, the foregoing and other objects and advantages, which will be better understood hereinafter, are achieved by a hydraulic brake control unit having the characteristics set forth in the appended claims.

[0007] In summary, a hydraulic brake control unit includes a cassette configured to be mounted within a handlebar body. The cassette defines an internal longitudinal cavity having a port at one end thereof. A longitudinally movable piston is partially housed in the longitudinal cavity. A transmission rod pivotally mounted on the handlebar body about a transverse axis acts between the brake control lever and the piston to apply a thrust on the piston in a first longitudinal direction toward the port. A passage is formed within the cassette defining a U-shaped path for brake fluid, wherein the passage fluidically couples the port of the longitudinal cavity to a hydraulic hose, the hydraulic hose also housed in the handlebar body.

[0008] Preferred embodiments are listed in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Several preferred but non-limiting embodiments of the hydraulic brake control unit according to the present invention will now be described; with reference to the accompanying drawings, in which:

[0010] Figure 1 A cross-sectional view of a hydraulic brake control assembly integrated into a handlebar tube of a handlebar-guided vehicle.

[0011] Figure 2 Similar to Figure 1 , but the cross-sectional views are obtained from different section angles.

[0012] Figure 3 Similar to Figure 1 and Figure 2 , but another cross-sectional view taken from yet another different cross-sectional angle.

[0013] Figure 4 for Figure 1 The details are in a cross-sectional view at an enlarged ratio. DETAILED DESCRIPTION

[0014] Referring to the drawings, a control unit for hydraulic brakes of a handlebar-guided vehicle (particularly (but not limited to) a bicycle) is integrated in a handlebar tube 10 , and more specifically at a straight end of the handlebar tube 10 .

[0015] The handlebar tube 10 defines a central axis x, referred to herein as "longitudinal." Throughout this specification and the appended claims, terms indicating orientation and direction, such as "longitudinal," "transversal," "external," and "internal," are to be interpreted with reference to the major axis x unless otherwise indicated.

[0016] A brake control lever 11 is mounted on the handlebar body 10 so as to be rotatable about an axis 11a transverse to the major axis x.

[0017] A cassette 12 is inserted into the handlebar tube 10 and is tightly matched therein, and a longitudinal hole 13 is formed inside thereof, with a position ( Figure 2 ) one end of the hole 13 and facing the end 10a ( Figures 1 to 3 The port 16 is used as a passage for the brake fluid used to operate the hydraulic brake.

[0018] A piston 14 is partially stored in a longitudinally movable manner in the longitudinal cavity 13. The piston 14 can be actuated by the brake control lever 11 through a transmission mechanism 15, which includes a transmission rod 17 mounted on the handlebar body 10 so that it can rotate around a transverse axis 17a.

[0019] According to one embodiment, the transmission rod 17 is formed as a rocker arm and has an arm 17 c that penetrates into the handlebar tube 10 through an opening 10 c and engages an end of the piston 14 that is away from the port 16 .

[0020] The drive rod 17 is operable by the brake rod 11 to exert a longitudinal thrust on the piston, causing it to advance in a first or longitudinal direction in the longitudinal cavity 13 toward the port 16 .

[0021] In the longitudinal cavity 13, a compression spring 19 is inserted between the piston 14 and the bottom of the longitudinal cavity 13 on the side of the port 16. The spring 19 urges the piston 14 away from the port 16.

[0022] In the cassette 12, a channel 18 is provided, which forms a U-shaped path for brake fluid; the channel 18 extends from the port 16 to a hydraulic hose 20, which is accommodated in the handlebar tube body 10 and extends in a second longitudinal direction or opposite to the first actuation direction of the piston 14 to transmit the pressure given by the piston 14 to a hydraulic caliper (not shown) when the brake control lever 11 is operated.

[0023] For structural reasons, the cassette 12 can be formed by combining multiple parts. The cassette 12 can be made of plastic material or metal material (such as aluminum or its alloy).

[0024] According to one embodiment, the transmission mechanism 15 may further include an intermediate rod 22 rotatably mounted on the brake control rod 11 around a transverse rotation axis 22 a .

[0025] According to the particular embodiment illustrated here, the intermediate lever 22 is mounted on the handlebar tube 10 in a manner rotatable about a transverse rotation axis 22 a coinciding with the transverse axis 11 a about which the brake control lever 11 is pivotally mounted.

[0026] In this embodiment, a wheel 21 which can rotate freely about a transverse rotation axis is mounted on an intermediate rod 22 .

[0027] When the brake lever 11 is actuated, it is pulled towards the handlebar tube 10 and the wheel 21 acts in a thrust relationship by abutting against and rolling along a surface 23 of the transmission rod 17 .

[0028] The intermediate rod 22 is pushed together with the brake control rod 11 by a spring 24 , and the spring 24 tends to drive the brake control rod 11 close to the handlebar tube body 10 , and also pushes the intermediate rod 22 toward the adjustment screw 25 installed on the handlebar brake control knob 11 .

[0029] The adjusting screw 25 is optional and can adjust the rest position of the brake lever 11 according to the size of the user's hand, especially according to the length of the user's fingers. When the brake lever 11 is pulled toward the handlebar body 10, the intermediate lever 12 is pushed by the adjusting screw 25 and rotates counterclockwise around the axis 22a.

[0030] In an alternative embodiment (not shown), the wheel 21 is rotatably mounted directly on the brake control lever 11. In this embodiment, the intermediate lever 22 and the adjustment screw 25 may not be present.

[0031] According to a preferred embodiment, a stop element 26 ( Figure 1 and Figure 3 ) can be fixed to the handlebar tube 10 in a stable position relative to the cassette 12 and in the rest or non-actuated position of the brake ( Figure 1 and Figure 3 ) cooperates with the protrusion 17b of the transmission rod 17 to determine the end-of-stroke position of the piston 14 relative to the end opposite to the end of the brake fluid supply port 16. Figure 1 and Figure 3 ), the thrust exerted by the spring 19 on the piston 14 is released onto the transmission rod 17, and its rotation is blocked by the stop element 26.

[0032] The cassette 12 is inserted into the handlebar tube 10 through its open end (on the right side) until the piston 14 abuts against the arm 17 c of the transmission rod 17 in a stop position determined by the protrusion 17 a resting on the stop element 26 .

[0033] According to a preferred embodiment, the cassette 12 also forms a storage tank 27 ( Figure 1 and Figure 3 ), which is also stored in the handlebar tube 10 and fluidically connected to the longitudinal cavity 13 ( Figure 1 ).

[0034] In a method known per se, one or more annular liners 29 are mounted on the piston 14, whose longitudinal position relative to the passage bore 28 determines the so-called "dead stroke", i.e. the length of the initial stretch covered by the piston during which a movement of the piston does not cause brake fluid to flow out of the longitudinal bore 13 through the port 16.

[0035] Preferably, the passage 18 in the cassette 12 is connected to the hose 20 ( Figure 2 ).

[0036] According to one embodiment, a longitudinal adjustment screw 31 is provided, acting on one end of the cartridge 12, to adjust the relative longitudinal position of the cartridge with respect to the piston 14. By adjusting the relative static position between the closure 29 on the piston 14 and the passage hole 28 in the cartridge 12, the "lost stroke" of the piston can be adjusted accordingly.

[0037] In the illustrated embodiment, the adjustment screw 31 engages through a central threaded hole 32 in a rigid disk-shaped plug 33 , preferably metal, which is secured within the handlebar tube 10 .

[0038] According to one embodiment, the longitudinal position of the rigid disc-shaped plug 33 inside the handlebar tube 10 is determined by a shoulder provided by a locking element 35 inserted into the handlebar tube 10 and preferably made of plastic material.

[0039] The locking element 35 may be provided with peripheral teeth 36 that snap and engage through openings 37 formed through the handlebar tube 10. The locking element 35 is a shoulder surface of a rigid disk-shaped plug 33 and has a central hole 38 therethrough adapted to receive the adjustment screw 31.

[0040] Preferably, the central hole 38 is at least partially aligned in a transverse plane with the peripheral locking teeth 36. Due to this configuration, the presence of the central adjusting screw 31 in the center of the locking element 35 prevents the peripheral teeth 36 from being defectively disengaged from the opening 37 of the handlebar tube 10. The brake control lever 11 is in this example secured by two complementary component half rings 39a, 39b ( Figure 2 ) components are mounted on the handlebar tube body 10.

[0041] During use, by actuating the brake control lever 11, i.e. pushing the brake control lever 11 towards the handlebar tube 10 in a manner known per se, the brake control 11 always rotates clockwise ( Figure 1 ), likewise causing the (optional) intermediate lever 22 to rotate clockwise therewith. The wheel 21 rolls along the specially shaped surface 23 of the transmission lever 17, causing the latter to rotate counterclockwise, pushing the piston 14 to the right in an actuating direction towards the end of the handlebars and pushing a certain amount of brake fluid filling the cavity 13 towards the port 16. Through the channel 18, the brake fluid performs a U-bend of its path and is introduced into the flexible hose 20 and from there is conveyed towards the brake calipers (not shown) on the wheels of the vehicle.

[0042] The shape of the surface 23 of the transmission rod 17 on which the wheel 21 rolls can be designed in a variable manner to adjust the load / stroke curve of the piston as required. The inclination of the rolling surface 23 for the wheel can be adjusted so that, for the same rotation angle of the intermediate rod 22, the transmission rod 17 can achieve a larger or smaller angle of rotation, and thus the linear stroke of the piston 14 is longer or shorter. This configuration allows to more or less emphasize the progression of the piston's stroke that changes during the stroke of the piston, for example, as the pull of the brake control lever 11 becomes increasingly rough, i.e. as it approaches the end of its stroke. For example, the surface 23 can be configured and variously inclined so that, with the same response given by the spring 19, the user can feel that the brake control lever 11 becomes increasingly difficult to pull as the brake control lever 11 gradually approaches the handlebar tube when the brake is applied.

[0043] According to one embodiment ( Figure 4 ), the surface 23 of the transmission rod 17 may have a slight groove 23a, preferably with a curvature corresponding to the curvature of the wheel 21, which serves as a seat for stably receiving the wheel in the non-actuated position of the brake. The groove 23a may extend to the rest of the surface 23 with a slight bump 23b, giving the user an ergonomic and helpful feeling of rocking when starting to brake.

[0044] The adjustment screw 31, in addition to allowing the adjustment of the longitudinal position of the cartridge 12 and the hole 13 relative to the piston 14, and thus the adjustment of the length of the lost travel, represents a stable shoulder surface which prevents the cartridge 12 from being ejected through one end (on the right) of the handlebar tube 10 during its operation due to the hydraulic thrust exerted by the piston 14.

[0045] Although specific embodiments of the present invention are disclosed, it should be understood that the disclosure is provided for illustrative purposes only and the present invention should not be limited in any way. Various modifications according to the foregoing examples should be obvious to those skilled in the art of the present invention. The scope of the present invention is limited only by the appended claims.

Claims

1. A hydraulic brake control unit for a handlebar-guided vehicle having a handlebar tube (10) including a hydraulic hose (20) therein, the unit comprising: A cassette (12) configured to be installed in the handlebar tube (10), wherein the cassette forms a longitudinal hole (13) inside and has a port (16) at one end of the longitudinal hole (13); a piston (14) partially received in the longitudinal cavity (13); a transmission rod (17) rotatably mounted on the handlebar tube (10) about a transverse axis (17a), the transmission rod (17) acting between a brake control lever (11) and the piston (14) to exert a thrust on the piston in a first longitudinal direction toward the port (16); A channel (18) is formed within the cassette (12) to define a U-shaped path for a brake fluid, the channel (18) fluidly coupling the port (16) of the longitudinal cavity (13) and the hydraulic hose (20) to apply a brake actuating pressure to the brake fluid contained in the hydraulic hose in a second longitudinal direction, the second longitudinal direction being opposite to the first longitudinal direction.

2. A control unit according to claim 1, comprising a roller (21) rotatable about a transverse axis (21a) and mountable on the brake control lever (11), wherein when the brake control lever (11) is actuated, the roller (21) acts by rolling along a surface (23) of the transmission rod (17).

3. A control unit according to claim 2, wherein the surface (23) of the transmission rod for rolling the roller (21) has a variable inclination thereon to provide a desired load / piston travel diagram.

4. A control unit according to claim 2 or 3, wherein the surface (23) has a groove (23a) for stably receiving the roller (21) in the non-actuated state of the brake.

5. The control unit according to claim 1 comprises a stop element (26) which can be fixed to the handlebar tube (10) and cooperates with a part (17a) of the transmission rod (17) to determine an end-of-stroke position of the piston (14) on the side of the piston farthest from the port (16).

6. A control unit according to claim 2, wherein the roller (21) can be directly mounted on the brake control lever (11) or on an intermediate lever (22), wherein the intermediate lever (22) is rotatably mounted on the handlebar tube (10) or on the brake control lever (11) around a transverse axis (22a), and wherein the angular position of the intermediate lever (22) relative to the brake control lever (11) can be adjusted by an adjustment screw (25).

7. A control unit according to any one of the preceding claims, wherein the transmission rod (17) is designed as a rocker arm and has an arm (17c) configured to penetrate into the handlebar body (10) through an opening (10c) of the handlebar body (10) and engage in a thrust relationship to an end of the piston farthest from the port (16).

8. The control unit according to claim 1, wherein the cassette (12) also forms an internal reservoir (27) for brake fluid.

9. The control unit according to claim 8, wherein the cartridge (12) further forms an internal passage (28) to allow fluid communication between the reservoir (27) and the longitudinal cavity (13).

10. A control unit according to any one of the preceding claims, further comprising a longitudinal adjustment screw (31) acting on an end of the cartridge (12) remote from the transmission rod (17) for adjusting the longitudinal position of the cartridge (12) relative to the piston (14).

11. The control unit according to claim 10, further comprising a rigid plate (33) which can be mounted in a longitudinally fixed manner inside the handlebar tube (10) and has a central screw hole (32) which is threadedly engaged with the adjustment screw (31).

12. A control unit according to claim 11, further comprising a longitudinal locking element (35) having a peripheral locking toothing (36) adapted to engage a corresponding opening (37) formed in the handlebar tube (10), the longitudinal locking element (35) determining a longitudinal fixing shoulder surface adapted for opposite displacements of the rigid plate (33).

13. A control unit according to claim 12, wherein the longitudinal locking element (35) has a central hole (38) which is at least partially aligned with the peripheral locking toothing (36) in a transverse plane and is capable of receiving a portion of the adjusting screw (31).

14. An assembly comprising a handlebar tube (10) for a handlebar-guided vehicle and a hydraulic brake control unit according to any one of the preceding claims.

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