Front derailleur of bicycle

Abstract

The utility model discloses a bicycle front derailleur which comprises a base, a chain guide piece and a connecting rod mechanism, the base is installed on a bicycle frame through a locking mechanism, and the connecting rod mechanism is configured to connect the chain guide piece to the base and can be operated to enable the chain guide piece to move relative to the base. An adjusting mechanism for adjusting the rotation range of the connecting rod mechanism is arranged on the base; the locking mechanism comprises a locking bolt and a locking nut, and the base is provided with an embedding hole for embedding the locking nut into the base; the adjusting mechanism comprises an adjusting bolt, and the base is provided with an adjusting hole matched with the adjusting bolt. The embedded hole and the adjusting hole are both arranged on the same side of the base, and the hole depth directions of the embedded hole and the adjusting hole are parallel. According to the front derailleur, the embedding hole and the adjusting hole are formed in the same side of the base of the front derailleur, and the hole depth directions of the embedding hole and the adjusting hole are parallel, so that mold splitting is easy during mold manufacturing, and the production and processing cost and difficulty are reduced.

Description

Technical Field

[0001] The utility model relates to the field of bicycles, in particular to a front derailleur of a bicycle. Background Art

[0002] Speed-shifting bicycles are increasingly becoming a popular means of transportation and recreation. These bicycles have a speed shifting device, including a front derailleur for shifting the chain. The front derailleur can be connected to a bicycle frame via a fixing device, ensuring that the front derailleur is stably supported on the bicycle frame.

[0003] In the prior art, patent application CN107042867B discloses a bicycle front derailleur comprising a base member, a chain guide, a coupling assembly, and a support structure. The base member is configured to be mounted on a bicycle frame. The coupling assembly is configured to movably connect the chain guide to the base member, thereby enabling the chain guide to move relative to the base member between a retracted position and an extended position. The support structure comprises a support member and a contact member. The support member is configured to be mounted on the base member and to advance toward the bicycle frame in a first direction. The contact member comprises a contact portion and a connecting portion extending from the contact portion. The contact portion is configured to contact the support member and the bicycle frame, and the connecting portion is configured to be movably connected to the base member. This structure is relatively complex, resulting in significant manufacturing difficulty and cost.

[0004] Therefore, it is necessary to provide a front derailleur that is simple in structure, easy to manufacture, and has low manufacturing cost. Utility Model Content

[0005] The present application provides a bicycle front derailleur to solve the problems existing in the prior art.

[0006] This application adopts the following technical solutions:

[0007] A bicycle front derailleur comprises a base, a chain guide and a connecting rod mechanism, wherein the base is mounted to the bicycle frame via a locking mechanism, the connecting rod mechanism is configured to connect the chain guide to the base and is operable to enable the chain guide to move relative to the base, and an adjustment mechanism for adjusting the rotation range of the connecting rod mechanism is provided on the base; the locking mechanism comprises a locking bolt and a locking nut, and the base has an embedding hole for embedding the locking nut into the base; the adjustment mechanism comprises an adjusting bolt, and the base has an adjusting hole adapted to the adjusting bolt; wherein the embedding hole and the adjusting hole are both arranged on the same side of the base, and the depth directions of the two holes are parallel.

[0008] The utility model designs a front derailleur for a bicycle. An embedding hole for embedding a locking nut and an adjustment hole matched with an adjustment bolt are provided on the same side of the base of the front derailleur, and the depth directions of the two holes are parallel. The structure is simple and mold separation is easy during mold manufacturing, thereby reducing the cost and difficulty of production and processing.

[0009] Furthermore, the chain guide comprises an inner derailleur plate and an outer derailleur plate, and a chain accommodating space is formed between the inner and outer derailleur plates.

[0010] Furthermore, the chain accommodating space is configured such that its width tends to increase in the direction away from the base, which is consistent with the angle of chain swing in the chain accommodating space, thereby avoiding chain rubbing.

[0011] Furthermore, the embedding hole is configured to limit the rotation of the locking nut, and the axes of the locking bolt and the adjusting bolt are perpendicular to each other, thereby preventing the locking nut from rotating during installation and facilitating installation.

[0012] Furthermore, there are two adjustment holes, namely a first adjustment hole and a second adjustment hole; there are two adjustment bolts, namely a first adjustment bolt and a second adjustment bolt; the first adjustment bolt is operably adapted to the first adjustment hole to limit the extreme position of the connecting rod mechanism rotating to the front side; the second adjustment bolt is operably adapted to the second adjustment hole to limit the extreme position of the connecting rod mechanism rotating to the rear side; the adjustment bolt and the adjustment hole cooperate to limit the rotation range of the connecting rod mechanism.

[0013] Furthermore, the connecting rod mechanism includes a first connecting rod and a second connecting rod, and the first connecting rod has: a front protrusion, which cooperates with the first adjusting bolt to form an extreme position for limiting the rotation of the connecting rod mechanism to the front side; and a rear protrusion, which cooperates with the second adjusting bolt to form an extreme position for limiting the rotation of the connecting rod mechanism to the rear side. The front protrusion and the rear protrusion cooperate with the first adjusting bolt and the second adjusting bolt respectively to limit the rotation range of the first connecting rod.

[0014] Furthermore, the first connecting rod includes a pair of connecting plates arranged at an interval, and the front convex portion and the rear convex portion are configured on one of the pair of connecting plates.

[0015] Furthermore, one end of a pair of connecting plates is connected to the base through a first pivot, and the other end is connected to the chain guide through a second pivot. A return spring for braking the chain guide to reset is provided on the second pivot. The return spring can provide elastic force for the chain guide to restore it to its initial position.

[0016] Furthermore, the first connecting rod has a hook-shaped portion, and the reset spring is a torsion spring. The first leg of the torsion spring abuts against the hook-shaped portion, and the second leg abuts against the chain guide to generate a restoring force to reset the brake chain guide.

[0017] Furthermore, one end of the second connecting rod is connected to the base through a third pivot, and the other end is connected to the chain guide through a fourth pivot. The second connecting rod has a wire fixing portion extending outward. Pulling the wire fixing portion can drive the chain guide to move relative to the base.

[0018] This utility model's bicycle front derailleur features a base with an embedding hole for a locking nut and an adjustment hole for an adjusting bolt on the same side. The holes are parallel in depth, simplifying the structure and facilitating mold separation, thus reducing production costs and difficulty. Furthermore, the coordination of the adjusting bolt and connecting rod mechanism allows for convenient adjustment of the chain guide's rotational range, enabling precise shifting control. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described below only relate to some embodiments of the present application, and are not limitations to the present application.

[0020] Figure 1 It is a schematic diagram of the entire structure of the utility model;

[0021] Figure 2 It is an exploded view of the overall structure of the utility model;

[0022] Figure 3 This is a schematic diagram of the base structure of the utility model;

[0023] Figure 4 This is a cross-sectional view of the overall structure of the utility model;

[0024] Figure 5 It is a schematic diagram of the overall structure of the utility model from another perspective.

[0025] Description of reference numerals:

[0026] 1-base; 10-first adjustment hole; 100-second adjustment hole; 11-embedding hole; 110-locking bolt; 111-locking nut; 101-first adjustment bolt; 102-second adjustment bolt; 2-first connecting rod; 20-connecting plate; 201-front convex portion; 202-rear convex portion; 203-hook-shaped portion; 3-second connecting rod; 30-wire fixing portion; 4-first pivot; 40-second pivot; 41-third pivot; 42-fourth pivot; 5-chain guide; 50-inner derailleur plate; 51-outer derailleur plate; 6-return spring; 60-first support leg; 61-second support leg. DETAILED DESCRIPTION

[0027] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the present application will be further described in detail below with reference to the accompanying drawings. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0029] Unless otherwise defined, technical or scientific terms used in this patent document shall have the ordinary meaning as understood by persons of ordinary skill in the art to which this application belongs. The terms "first," "second," and similar expressions used in this patent specification and claims do not denote any order, quantity, or importance, but are merely used to distinguish one component from another. Similarly, terms such as "a," "an," or "the" do not denote a limitation of quantity, but rather denote the presence of at least one. Terms such as "include" or "comprising" mean that the elements or objects preceding the phrase "include" or "comprising" include the elements or objects listed after the phrase and their equivalents, and do not exclude other elements or objects. Terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" are used solely to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. These terms are used solely to facilitate the description of this application and to simplify the description. They are not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation, and are not to be construed as limitations on this application.

[0030] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0031] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the features of the following embodiments can be combined with each other.

[0032] Example 1:

[0033] Please see Figure 1-Figure 5 The present embodiment provides a bicycle front derailleur, which has a reasonable structural design, is easy to manufacture, and has a low manufacturing cost. At the same time, it can be stably supported on the bicycle frame and accurately control the switching of the chain between the front sprockets.

[0034] Please see Figure 1 Specifically, the bicycle front derailleur of this embodiment comprises a base 1, a chain guide 5, and a linkage mechanism. The base 1 is the core supporting component of the entire front derailleur and is securely mounted to the bicycle frame via a locking mechanism. The linkage mechanism is responsible for coupling the chain guide 5 to the base 1 and enabling relative movement of the chain guide 5. The base 1 is also equipped with an adjustment mechanism for adjusting the rotation range of the linkage mechanism, thereby precisely controlling the movement distance and angle of the chain guide 5.

[0035] The base 1 is made of aluminum alloy casting to support the entire front derailleur and withstand various forces generated during use. The base 1 is provided with an embedding hole 11 and an adjustment hole for installing a locking mechanism and an adjustment mechanism respectively.

[0036] See also Figure 1-Figure 3 The embedding hole 11 is configured to restrict the rotation of the locking nut 111. In this embodiment, the locking nut 111 is a square nut, and the shape of the embedding hole 11 matches the locking nut 111, preventing the locking nut 111 from rotating within the embedding hole 11. Other nuts may also be used for locking. Thus, during installation, the base 1 can be securely fixed to the bicycle frame by simply inserting the locking bolt 110 through the bicycle frame and screwing it into the locking nut 111. Since the locking nut 111 is restricted from rotating by the embedding hole 11, the installation process is simpler and faster.

[0037] The adjustment holes include a first adjustment hole 10 and a second adjustment hole 100, which are used to install a first adjustment bolt 101 and a second adjustment bolt 102, respectively. The first adjustment hole 10 and the second adjustment hole 100 are both located on the same side of the base 1 and are parallel to the depth direction of the embedded hole 11. The depth direction of the embedded hole 11 is the installation direction of the locking nut 111. The opening directions of the embedded hole 11 and the adjustment hole are parallel, and the axis of the locking bolt 110 is perpendicular to the axis of the adjustment hole. During mold manufacturing, the embedded hole 11 and the adjustment hole are formed by protrusions and columns that are respectively arranged on the mold so as to face the same direction. This design makes it easier to separate the base 1 during mold manufacturing, reducing the cost and difficulty of production and processing.

[0038] See also Figure 5The chain guide 5 is responsible for guiding the chain between the front sprockets of the bicycle. In this embodiment, the chain guide 5 includes an inner derailleur plate 50 and an outer derailleur plate 51, forming a chain-holding space between them. The width of the chain-holding space tends to increase in the direction away from the base 1. When the chain is switched, the chain moves axially along the sprockets. The chain farther from the base 1 moves more significantly, requiring a larger space for movement. This is consistent with the angular change of the chain during swinging, thus preventing friction or interference between the chain and the derailleur plate.

[0039] The inner derailleur plate 50 and the outer derailleur plate 51 are integrally formed, reducing the difficulty and cost of production and processing. At the same time, the chain space between the two is reasonably designed to ensure smooth and unobstructed chain switching.

[0040] See also Figure 1-Figure 5 The link mechanism includes a first link 2 and a second link 3 , which cooperate to achieve the movement of the chain guide 5 relative to the base 1 .

[0041] One end of the first link 2 is pivotally connected to the base 1 via a first pivot 4, and the other end is pivotally connected to the chain guide 5 via a second pivot 40. The first link 2 has a front projection 201 and a rear projection 202, which engage with the first and second adjustment bolts 101, 102, respectively, to limit the forward and rearward rotation limits of the link mechanism. The first link 2 rotates about the first pivot 4. When the front projection 201 abuts the first adjustment bolt 101, the link mechanism reaches its forward rotation limit, driving the chain guide 5 to its extended position. When the rear projection 202 abuts the second adjustment bolt 102, the link mechanism reaches its rearward rotation limit, driving the chain guide 5 to its retracted position. The provision of the front and rear projections 201, 202 allows for precise control of the link mechanism's rotational range, ensuring that the chain guide 5 does not exceed the limit, preventing the chain from falling off the sprocket.

[0042] See also Figure 4 The first connecting rod 2 further includes a pair of spaced connecting plates 20, with the front convex portion 201 and the rear convex portion 202 being disposed on one of the connecting plates 20. This design makes the structure of the first connecting rod 2 more compact and stable.

[0043] Please see Figure 1 One end of the second connecting rod 3 is pivotally connected to the base 1 via a third pivot 41, and the other end is pivotally connected to the chain guide 5 via a fourth pivot 42. The second connecting rod 3 has a cable attachment portion 30 extending outward. When the cable is pulled, the cable attachment portion 30 drives the second connecting rod 3, which in turn, through the transmission action of the linkage mechanism, moves the chain guide 5 relative to the base 1.

[0044] See also Figure 1 or Figure 4 To ensure that the chain guide 5 automatically returns to its initial position after the shift is complete, this embodiment further includes a return spring 6 mounted on the second pivot 40. This return spring 6 is a torsion spring, with its first leg 60 abutting the hook 203 of the first link 2 and its second leg 61 abutting the chain guide 5. Thus, upon completion of the shift, the return spring 6 generates a restoring force, causing the chain guide 5 to automatically return to its initial position.

[0045] During the chain switching process, the connecting rod mechanism drives the chain guide 5 to move between the extended position and the retracted position of the base 1. The specific actions are as follows:

[0046] As the chain guide 5 moves toward the extended position, the first link 2 begins to rotate. As the rotation progresses, the front projection 201 of the first link 2 contacts the first adjustment bolt 101, marking the first link 2's maximum forward rotational position. The chain guide 5 now moves to the extended position. In this position, the chain guide 5 and the second pivot 40 drive the return spring 6 to rotate. This rotation generates a spring force that propels the chain guide 5 back to its initial position. Conversely, when the rear projection 202 of the first link 2 contacts the second adjustment bolt 102, the first link 2 reaches its maximum rearward rotational position. At this point, the chain guide 5 moves to the retracted position. The return spring 6 rotates with the movement of the chain guide 5 and the second pivot 40. The spring force generated by this rotation drives the second pivot 40, thereby returning the chain guide 5 to its initial position.

[0047] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A bicycle front derailleur, comprising a base (1), a chain guide (5) and a linkage mechanism, wherein the base (1) is mounted to a bicycle frame by means of a locking mechanism, the linkage mechanism being configured to couple the chain guide (5) to the base (1) and operable to enable the chain guide (5) to move relative to the base (1), and an adjustment mechanism for adjusting the rotation range of the linkage mechanism being provided on the base (1); characterized in that: The locking mechanism comprises a locking bolt (110) and a locking nut (111), and the base (1) is provided with an embedding hole (11) for embedding the locking nut (111) into the base (1); The adjustment mechanism comprises an adjustment bolt, and the base (1) has an adjustment hole adapted to the adjustment bolt; The embedding hole (11) and the adjustment hole are both arranged on the same side of the base (1), and the depth directions of the two holes are parallel.

2. The bicycle front derailleur according to claim 1, wherein: The chain guide (5) comprises an inner derailleur plate (50) and an outer derailleur plate (51), and a chain accommodating space is formed between the inner and outer derailleur plates (51).

3. The bicycle front derailleur according to claim 2, wherein: The chain-containing space is configured such that its width tends to increase in a direction away from the base (1).

4. The bicycle front derailleur according to claim 1, wherein: The embedding hole (11) is configured to limit the rotation of the locking nut (111), and the axes of the locking bolt (110) and the adjusting bolt are perpendicular to each other.

5. The bicycle front derailleur according to claim 1 or 4, characterized in that: The adjustment holes are configured into two, namely a first adjustment hole (10) and a second adjustment hole (100); The adjusting bolts are configured in two, namely a first adjusting bolt (101) and a second adjusting bolt (102); The first adjusting bolt (101) is operably adapted to fit the first adjusting hole (10) to limit the extreme position of the connecting rod mechanism's rotation toward the front side; The second adjusting bolt (102) is operably adapted to fit the second adjusting hole (100) to limit the limit position of the rearward rotation of the link mechanism.

6. The bicycle front derailleur according to claim 5, characterized in that: The connecting rod mechanism comprises a first connecting rod (2) and a second connecting rod (3), wherein the first connecting rod (2) has: a front convex portion (201) which cooperates with the first adjusting bolt (101) to form a limit position for limiting the rotation of the link mechanism toward the front side; and The rear convex portion (202) cooperates with the second adjusting bolt (102) to form a limit position for limiting the rotation of the link mechanism toward the rear side.

7. The bicycle front derailleur according to claim 6, wherein: The first connecting rod (2) comprises a pair of connecting plates (20) arranged at intervals, and the front convex portion (201) and the rear convex portion (202) are arranged on one of the pair of connecting plates (20).

8. The bicycle front derailleur according to claim 7, wherein: One end of the pair of connecting plates (20) is rotatably connected to the base (1) via a first pivot (4), and the other end is rotatably connected to the chain guide (5) via a second pivot (40). The second pivot (40) is provided with a return spring (6) for returning the brake chain guide (5).

9. The bicycle front derailleur according to claim 8, wherein: The first connecting rod (2) has a hook-shaped portion (203), and the reset spring (6) is a torsion spring. The first leg (60) of the torsion spring abuts against the hook-shaped portion (203), and the second leg (61) of the torsion spring abuts against the chain guide (5) to generate a restoring force for resetting the brake chain guide (5).

10. The bicycle front derailleur according to claim 6, wherein: One end of the second connecting rod (3) is rotatably connected to the base (1) via a third pivot (41), and the other end is rotatably connected to the chain guide (5) via a fourth pivot (42). The second connecting rod (3) has a wire fixing portion (30) extending outward.

Images