Actuator for a bicycle gear-shift

• US 7,086,974 B2
• Filed: 04/25/2003
• Issued: 08/08/2006
• Est. Priority Date: 04/26/2002
• Status: Expired due to Term

• Current Assignee: Campagnolo S.R.L.
• Original Assignee: Campagnolo S.R.L.
• Inventors: Dal Prà, Guiseppe
• Primary Examiner(s): Johnson, Vicky A.
• Application Number:
  US10/423,312
• Publication Number:
  US 20040014541A1
• Time in Patent Office: 1,201 Days
• Field of Search: 474/70, 474 78- 83
• US Class Current: 474/78
• CPC Class Codes: B62M 25/08 with electrical or fluid transmitting systems
• CPC Class Codes: B62M 9/122 electrically or fluid actuated; Controls thereof
• CPC Class Codes: B62M 9/1244 limiting or positioning the movement

Abstract

A bicycle gear-shift actuator (10, 100) having an articulated quadrilateral support (11) with four connecting rods (21, 22, 23, 24) hinged together by four pin elements (41, 42, 43, 44), and a motor member (12), having a variable length output shaft that travels along a drive axis (13) between two opposite pin elements (41, 42) to move them for deforming the articulated quadrilateral (11). Preferably, the drive axis (13) perfectly intersects the pin axis (32) of at least one (42) of the two pin elements (41, 42).

Claims

1. Actuator device (10, 100) for a bicycle gear-shift, comprising:

an articulated quadrilateral (11) with four connecting rods (21, 22, 23, 24) hinged together according to four pin axes (31, 32, 33, 34) by four pin elements (41, 42, 43, 44), in which the first connecting rod (21) is intended to be integrally fixed to the bicycle frame, the second connecting rod (22) is opposite to the first connecting rod (21) in the articulated quadrilateral (11) and is intended to be fixed to a support for a gear-shift derailleur; and

a drive member (12), having a variable length according to a drive axis (13) and active between two opposite pin elements (41, 42) to move them towards and away from each other deforming the articulated quadrilateral (11);

wherein the drive axis (13) substantially intersects the pin axis (31, 32) of both the two pin elements (41, 42) between which the drive member (12) is active;

wherein the drive axis (13) perfectly intersects at least one of the pin axes (31, 32) of the two pin elements (41, 42) between which the drive member (12) is active;

wherein the drive member (12) comprises an electric motor (52) housed on a support (51) mounted on a first (41) of the pin elements, a screw (53) arranged axially along the drive axis (13) and put into rotation by the electric motor (52), a nut screw (54) engaged with the screw (53) and fixed to a second (42) of the pin elements opposite the first (41), wherein the drive axis (13) perfectly intersects the axis (32) of the second pin element (42);

wherein the connecting rods (21, 22, 23, 24) have a substantial width in the direction of the pin axes (31, 32, 33, 34), with such a width defining an internal space in the articulated quadrilateral (11), wherein the drive member (12) is arranged inside such an internal space; and

wherein the nut screw (54) comprises a tubular body (541) threaded internally, and two pin portions (542, 543) opposite each other and perpendicular to the tubular body (541).

2. Device according to claim 1, in which the second pin element (42) also comprises two opposite pins (421, 422), each inserted in hinging holes formed in the connecting rods (22, 23) converging in the second pin element (42) and in the pin portions (542, 543) of the nut screw (54).

3. Device according to claim 1, in which the tubular body (541) of the nut screw (54) is closed at one of its ends (544) and has a length such as to receive the screw (53) during the maximum contraction of the drive member (12).

4. Actuator device (10, 100) for a bicycle gear-shift, comprising:

an articulated quadrilateral (11) with four connecting rods (21, 22, 23, 24) hinged together according to four pin axes (31, 32, 33, 34) by four pin elements (41, 42, 43, 44), in which the first connecting rod (21) is intended to be integrally fixed to the bicycle frame, the second connecting rod (22) is opposite to the first connecting rod (21) in the articulated quadrilateral (11) and is intended to be fixed to a support for a gear-shift derailleur; and

a drive member (12), having a variable length according to a drive axis (13) and active between two opposite pin elements (41, 42) to move them towards and away from each other deforming the articulated quadrilateral (11);

wherein the drive axis (13) substantially intersects the pin axis (31, 32) of both the two pin elements (41, 42) between which the drive member (12) is active;

wherein the drive axis (13) perfectly intersects at least one of the pin axes (31, 32) of the two pin elements (41, 42) between which the drive member (12) is active;

wherein the drive member (12) comprises an electric motor (52) housed on a support (51) mounted on a first (41) of the pin elements, a screw (53) arranged axially along the drive axis (13) and put into rotation by the electric motor (52), a nut screw (54) engaged with the screw (53) and fixed to a second (42) of the pin elements opposite the first (41), wherein the drive axis (13) perfectly intersects the axis (32) of the second pin element (42);

wherein a degree of freedom is provided between the motor (52) and the articulated quadrilateral (11); and

wherein the degree of freedom is provided by a Hooke'"'"'s joint between the screw (53) and the motor (52).

5. Actuator device (10, 100) for a bicycle gear-shift, comprising:

an articulated quadrilateral (11) with four connecting rods (21, 22, 23, 24) hinged together according to four pin axes (31, 32, 33, 34) by four pin elements (41, 42, 43, 44), in which the first connecting rod (21) is intended to be integrally fixed to the bicycle frame, the second connecting rod (22) is opposite to the first connecting rod (21) in the articulated quadrilateral (11) and is intended to be fixed to a support for a gear-shift derailleur; and

a drive member (12), having a variable length according to a drive axis (13) and active between two opposite pin elements (41, 42) to move them towards and away from each other deforming the articulated quadrilateral (11), wherein the drive axis (13) substantially intersects the pin axis (31, 32) of both the two pin elements (41, 42) between which the drive member (12) is active; and

a mechanical fuse in a coupling between the drive member (12) and the articulated quadrilateral (11);

wherein the mechanical fuse comprises a calibrated interference between a Hooke'"'"'s joint and at least one among a motor (52) and a threaded screw (53).