Cable support for a derailleur

Abstract: A cable support member includes a base member (114) having an opening (122) for receiving a fastener for fastening the base member to the bicycle. First and second spaced apart cable guides (118, 120) are integrally formed with and extend from the base member. The first and/or second cable guides (118, 120) may be formed as panels, each of which may have an opening (124, 132) for receiving a derailleur cable therethrough. A rib (150) may be provided which extends from the first cable guide (118) toward the second cable guide (120) to help reinforce the first and second cable guides.

Description: BACKGROUND OF THE INVENTION The present invention is directed to a cable support member according to the preamble of claim 1. An example of such a support member may be seen in DE-U-9313254. Fig. 1 shows a prior art bicycle derailleur (10) affixed to a mounting member (14). Mounting member (14) may be a separate mounting member that is adapted to be affixed to a bicycle frame, or it may be a portion of the bicycle frame itself. Derailleur (10) includes a base member (18) affixed to mounting member (14) through a bolt (22); a linkage mechanism (26); and a chain guide assembly (30). Base member (18) may be the main attachment member for the derailleur, or it may be a cover for the main attachment member for the derailleur. An end of an inner wire (34) of a derailleur cable (38) is affixed to chain guide assembly (30) through a cable fixing bolt (42). An outer casing (46) of derailleur cable (38) is supported by a separate cable retainer (50). When inner wire (34) is pulled or released, chain guide assembly (30) moves relative to base member (18) in a known manner to shift a chain (no shown) among a plurality of sprockets shown schematically at (54). Prior art derailleurs such as derailleur (10) have the disadvantage that a separate cable retainer (50) is used to fix the derailleur cable (38) to the derailleur. This increases the manufacturing expense of the derailleur and makes assembly more complicated. Some prior art derailleurs mold the cable retainer with the base member (18) as a very thick portion of the base member which is subsequently drilled with a bore to receive the derailleur cable. The disadvantage of this structure is that a substantial amount of the material used to form the base member is wasted because of the drilled bore, and the drilling operation adds to the time and expense of manufacture. SUMMARY OF THE INVENTION The present invention is defined by a cable support member for a bicycle derailleur as claimed in Claim 1. According to the present invention, a cable support member includes a base member having an opening for receiving a fastener for fastening the base member to the bicycle. First and second spaced apart cable guides are integrally formed with and extend from the base member. In a more specific embodiment, the first and/or second cable guides may be formed as panels. Each of the cable guides has an opening for receiving a portion of a derailleur cable therethrough. Furthermore, a rib is provided which extends from the first cable guide toward the second cable guide to help reinforce the first and/or second cable guides. In any event, a cable support member constructed in accordance with the present invention may be stamped from sheet metal or may be molded from plastic or some other material very inexpensively and without the added steps or waste inherent in the methods used to manufacture prior art structures. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view of a prior art derailleur; Fig. 2 is a side view of a derailleur using a particular embodiment of a cable support member according to the present invention; Fig. 3 is a front view of the cable support member shown in Fig. 1; Fig. 4 is a rear view of the cable support member shown in Fig. 3; Fig. 5 is a view of the cable support member taken along line V-V in Fig. 4; Fig. 6A is a view of the cable support member taken along line VI-VI in Fig. 4; Fig. 6B is a view of an alternative embodiment of the portion of the cable support member shown in Fig. 6A; Fig. 7A is a view of the cable support member taken along line VII-VII in Fig. 4; Fig. 7B is a view of an alternative embodiment of the portion of the cable support member shown in Fig. 7A; and Fig. 8 is a detailed view of an alternative embodiment of a cable support member according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS Fig. 2 is a side view of a derailleur (100) according to the present invention. Derailleur (100) is similar to derailleur (10) shown in Fig. 1 in that derailleur (100) also has a mounting member (14), a bolt (22), a linkage mechanism (26), a chain guide assembly (30), a derailleur cable (38), and a cable fixing bolt (42). However, rather than have a separate base member (18) and cable retainer (50), derailleur (100) includes an integrated cable support member (110) which, in this embodiment, performs both functions. Figs. 3-5 show different views of a particular embodiment of cable support member (110). In this embodiment, cable support member (110) includes a base member (114) and first and second cable guides (118,120) extending from a side surface of base member (110). Base member (114) includes an opening (122) for receiving a fastener (such as bolt (22) for fastening base member (114) to the bicycle. In this embodiment, cable guides (118,120) are formed as flat panels; the diameter D of first cable guide (118) is greater than the thickness (T) of first chain guide (118); the diameter (d) of second cable guide (120) is greater than the thickness (t) of second cable guide, diameter d is less than or equal to D, and T=t. Of course, the panels do not necessarily have to be flat, and the size, thickness and shape of the panels may be varied according to the application, and the measurements of one panel may be switched with the other. As with the prior art derailleurs, base member (114) may be the main attachment member for the derailleur, or it may be a cover for the main attachment member for the derailleur. As shown in Fig. 5, base member (114) includes openings (123) for attachment of linkage mechanism (26). Similar openings are also disposed on the other side of base member (114). In this embodiment cable support member (110) is stamped from sheet metal, but it also may be formed from cast or molded metal or plastic. Fig. 6A is a view of cable guide (118) taken along line VI-VI in Fig. 4. As shown in Fig. 6A, cable guide (118) has an opening (124) for receiving a portion of the derailleur cable (38) therethrough. Preferably, opening (124) is wide enough to receive the outer casing (46) of derailleur cable (38), but such a width is not necessary and may be smaller if desired. Furthermore, as shown in Fig. 6B, cable guide (118) may include a passage (128) which allows a portion of derailleur cable (38) to pass through the side thereof. Groove (128) may be sufficiently big to allow outer casing (46) to pass through, preferably with some interference, but it may also be sized to allow inner cable (34) but not outer casing (46) to pass through. Fig. 7A is a view of cable guide (120) taken along line VII-VII in Fig. 4. As shown in Fig. 7A, cable guide (120) has an opening (132) for receiving a portion of the derailleur cable (38) therethrough. In this embodiment, opening (132) is wide enough to receive the inner cable (34) but not outer casing (46) of derailleur cable (38), but such a width is not necessary and may be larger if desired. Furthermore, as shown in Fig. 7B, cable guide (120) may include a passage (134) which allows a portion of derailleur cable (38) to pass through the side thereof. In this embodiment, passage (134) is sufficiently big to allow only inner cable (34) to pass through, but again the size of passage (134) may be varied as desired for the particular application. Cable support member (110) also includes a rib (150) which helps to reinforce the cable guides (118,120). In this embodiment, rib (150) extends from the first cable guide (118) toward the second cable guide (120) and connects the first cable guide (118) to the second cable guide (120). Rib (150) may be integrally formed with the first cable guide (118) and/or the second cable guide (120), or the rib may touch first cable guide (118) and/or second cable guide (120) without being integrally formed therewith. For example, Fig. 4 shows rib (150) formed integrally with cable guide (120) and touching cable guide (118). Alternatively, rib (150) may extend toward cable guide (118) and/or cable guide (120) without actually touching the cable guide. For example, Fig. 8 shows rib (150) integrally formed with cable guide (120) and extending toward cable guide (118) but without touching cable guide (118). This construction is useful when the entire derailleur cable (38) fits within cable guide (118) so that most of the force exerted by the shifting operation is borne by cable guide (120). In this case reinforcement of cable guide (120) may be desirable, but reinforcement of cable guide (118) is unnecessary. Rib 150 need only extend far enough to provide reinforcement of cable guide (120) and may be quite short. In this embodiment, rib (150) is integrally formed with base member (114). While rib (150) is shown with a width less than the diameter of cable guides (118, 120) to save material and facilitate manufacture, it may be desirable to form rib (150) with a diameter equal to cable guide (118) and/or cable guide (120) or even with a larger width, in which case rib (150) would bend around the top of cable guide (118) and/or cable guide (120). While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the scope of the present invention. Thus, the scope of the invention should not be limited by the specific structures disclosed. Instead, the true scope of the invention should be determined by the following claims.

Claims: A cable support member (110) for a bicycle derailleur comprising: a base member (114) having an opening (112) for receiving a fastener for fastening the base member to the bicycle; a first cable guide (118) integrally formed with and extending from the base member, the first cable guide having a first opening for receiving a portion of a derailleur cable (38) therethrough; a second cable guide (120) integrally formed with and extending from the base member (114), the second cable guide (120) having a second opening for receiving a portion of the derailleur cable (38) therethrough; and wherein the first cable guide (118) is spaced apart from the second cable guide (120), characterised in that the cable support member (110) further comprises a rib (150) integrally formed with and extending from the base member (114), the rib (150) extending from the first cable guide (118) toward the second cable guide (120). The cable support member according to Claim 1 wherein the first cable guide (118) is formed as a first panel, and wherein the second cable guide (120) is formed as a second panel. The cable support member according to Claim 2 wherein a thickness of the first panel is less than a diameter of the first panel. The cable support member according to either of Claims 2 or 3 wherein a thickness of the second panel is less than a diameter of the second panel. The cable support member according to any of Claims 2 to 4 wherein the thickness of the first panel is equal to the thickness of the second panel. The cable support member according to any of Claims 2 to 5 wherein the diameter of the first panel is equal to the diameter of the second panel. The cable support member according to any preceding claim wherein the first opening is larger than the second opening. The cable support member according to Claim 1 wherein the first cable guide (118) defines a first passage (128) through a side of the first cable guide into the first opening (124). The cable support member according to any preceding claim wherein the second cable guide defines a second passage through a side of the second cable guide into the second opening. The cable support member according to any preceding claim wherein the rib (150) connects the first cable guide (118) and the second cable guide (120). The cable support member according to any preceding claim wherein the rib (150) is integrally formed with the first cable guide (118). The cable support member according to any preceding claim wherein the rib (150) is integrally formed with the second cable guide (120). The cable support member according to any preceding claim wherein the rib (150) has a width (W) less than a diameter (d,D) of at least one of the first cable guide (118) or the second cable guide (120). The cable support member according to Claim 13 wherein the rib (150) has a width (W) less than a diameter (d,D) of both the first cable guide (118) and the second cable guide (120).

Inventors: ANDO YOSHIAKI, ANDO, YOSHIAKI
Applicants: SHIMANO KK, SHIMANO INC.
Application year: 1996
Main classification: B62M25
IPC codes: B62M25, B62J99, B62M9