A frame stem mounting and positioning structure

Abstract

This utility model relates to a frame stem mounting and positioning structure, including a fork sleeve and a handlebar stem. The handlebar stem is inserted into the fork sleeve and is securely connected to the fork sleeve by a fastening and positioning structure. The fastening and positioning structure includes an anti-rotation positioning component and a fastener disposed between the fork sleeve and the handlebar stem. The anti-rotation positioning component prevents circumferential rotation of the handlebar stem and the fork sleeve, and the fastener locks the handlebar stem securely installed in the fork sleeve. This utility model, through the design of the anti-rotation positioning component at the connection between the handlebar stem and the fork sleeve, forms a mechanical limiting structure. Even under strong impact or a decrease in bolt preload, it prevents relative rotation between the handlebar stem and the fork sleeve, ensuring that the handlebar and the front wheel always maintain the same direction. This avoids loss of steering control due to loosening or misalignment, significantly improving the safety, reliability, and durability of the steering system.

Description

Technical Field

[0001] This utility model relates to the field of frame connection structure technology, and in particular to a frame stem mounting and positioning structure. Background Technology

[0002] The steering system of electric bicycles and tricycles consists of handlebars, stem, and front fork. The stem's function is to fix the handlebars to the front fork sleeve, reliably transmit torque, and enable the front fork and front wheel to steer synchronously when the rider turns the handlebars.

[0003] The common connection between the handlebar stem and fork sleeve today involves inserting the handlebar stem into the fork sleeve (usually a straight steel fork). A wedge or expansion block mechanism converts the axial force of the bolt into radial friction, ensuring a tight fit between the stem and fork sleeve. With increasing demands for lightweight and high strength, modern bicycles are increasingly adopting threadless fork sleeves and upright stems. The stem is directly clamped to the outer wall of the fork sleeve by clamping bolts, and pre-tightened by the top cap bolts in conjunction with the headset to maintain a secure steering system.

[0004] The existing technologies mentioned above typically rely on the friction between the handlebar stem and the fork sleeve to achieve coaxial fixation when connecting them. There is no structure to restrict relative rotation between them. During riding, if the handlebar is subjected to a large impact (sudden braking, jumping, crashing, etc.), the torque may exceed the upper limit of the clamping friction. The stem may rotate slightly around the fork sleeve, causing the handlebar and the front wheel to be out of sync. Once relative rotation occurs, the rider's operation cannot be accurately transmitted to the front wheel. At high speeds or on complex terrain, this can cause steering deviation and loss of control risks. Therefore, it is necessary to continuously improve the technology based on market demand and customer feedback. Summary of the Invention

[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the existing technology and provide a frame stem mounting and positioning structure.

[0006] This utility model is achieved through the following technical solution:

[0007] A frame stem mounting and positioning structure includes a fork sleeve and a handlebar stem, characterized in that the handlebar stem is inserted into the fork sleeve and is fastened to the fork sleeve by a fastening positioning structure. The fastening positioning structure includes an anti-rotation positioning member and a fastener disposed between the fork sleeve and the handlebar stem. The anti-rotation positioning member can prevent the circumferential rotation of the handlebar stem and the fork sleeve, and the fastener can lock the handlebar stem into the fork sleeve.

[0008] According to the above technical solution, preferably, the anti-rotation positioning component includes a positioning pin and a positioning groove respectively provided on the handlebar stem and the fork sleeve.

[0009] According to the above technical solution, preferably, the positioning pin is disposed on the handlebar stem, and the positioning groove is disposed at the end of the fork sleeve. When the handlebar stem is securely connected to the fork sleeve, the positioning pin is placed in the positioning groove of the fork sleeve.

[0010] According to the above technical solution, preferably, the positioning pin is fixedly connected to the positioning ring, and the positioning ring is disposed on the outer wall of the handlebar stem.

[0011] According to the above technical solution, preferably, the positioning ring is fixedly connected to or detachably connected to the outer wall of the handlebar stem.

[0012] According to the above technical solution, preferably, two positioning pins are arranged opposite to each other, and two positioning slots are arranged opposite to each other.

[0013] According to the above technical solution, preferably, the fastener achieves a tight connection between the handlebar stem and the fork sleeve through threaded fastening.

[0014] According to the above technical solution, preferably, the fastener includes a fastening bolt and a beveled fastening head. The end of the fastening bolt is rotatably connected to the end of the handlebar stem, the middle of the fastening bolt is located inside the handlebar stem, and the other end of the fastening bolt is threadedly connected to the beveled fastening head. By rotating the fastening bolt, the beveled fastening head is made to abut tightly against the inside of the fork sleeve.

[0015] According to the above technical solution, preferably, the tail end of the handlebar stem and the end face of the beveled fastening head are both beveled structures, which are used to make the beveled fastening head generate radial displacement and tightly abut against the inner wall of the fork sleeve.

[0016] The beneficial effects of this utility model are:

[0017] The structure of this utility model is scientific and reasonable and easy to implement. Through the design of the anti-rotation positioning component at the connection between the handlebar stem and the fork sleeve, a mechanical limiting structure is formed. Even under strong impact or when the bolt preload decreases, it can prevent relative rotation between the handlebar stem and the fork sleeve, ensuring that the handlebar and the front wheel always maintain the same direction, avoiding loss of steering control due to loosening or deviation, and improving riding safety.

[0018] Meanwhile, the locating pins and locating grooves at the connection between the handlebar stem and the fork sleeve ensure that torque transmission relies not only on the friction of traditional fasteners, but also on the cooperation of the locating pins and locating grooves in the anti-rotation locating components. This further improves the durability of the connection between the stem and the fork sleeve and enhances the overall user experience. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0020] Figure 2 This is a partial three-dimensional view of the front fork sleeve of this utility model.

[0021] Figure 3 This is a three-dimensional structural diagram of the handlebar stem of this utility model.

[0022] Figure 4 This is a three-dimensional structural diagram of the fastener of this utility model.

[0023] Figure 5 This is a three-dimensional structural diagram of the inclined fastening head of this utility model.

[0024] Figure 6 This is a three-dimensional structural diagram of the lower part of the handlebar stem of this utility model.

[0025] In the diagram: 1. Handlebar stem; 2. Fork sleeve; 3. Positioning groove; 4. Positioning ring; 5. Positioning pin; 6. Angled fastener head; 7. Fastening bolt. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and preferred embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0027] In the description of the utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the utility model.

[0028] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0029] Example 1: As shown in the figure, this utility model includes a front fork sleeve 2 and a handlebar stem 1. The handlebar stem 1 is inserted into the front fork sleeve 2 and is fastened to the front fork sleeve 2 by a fastening positioning structure. The fastening positioning structure includes an anti-rotation positioning component and a fastener disposed between the front fork sleeve 2 and the handlebar stem 1. The anti-rotation positioning component can prevent the handlebar stem 1 and the front fork sleeve 2 from rotating circumferentially, and the fastener can lock the handlebar stem 1 into the front fork sleeve 2.

[0030] The anti-rotation positioning component includes positioning pins 5 and positioning grooves 3 respectively located on the handlebar stem 1 and the fork sleeve 2. The positioning pins 5 are located on the handlebar stem 1, and the positioning grooves 3 are located at the ends of the fork sleeve 2. In this example, preferably, but not limited to, two positioning pins 5 and two positioning grooves 3 are arranged opposite each other. When the handlebar stem 1 is securely connected to the fork sleeve 2, the positioning pins 5 are placed in the positioning grooves 3 of the fork sleeve 2. Through the cooperation of the positioning pins 5 and the positioning grooves 3, a mechanical limiting structure is formed to prevent relative rotation between the handlebar stem 1 and the fork sleeve 2, ensuring that the handlebars and the front wheel always maintain the same direction.

[0031] Specifically, in this example, the positioning pin 5 is fixedly connected to the positioning ring 4, which is located on the outer wall of the handlebar stem 1. The positioning ring 4 is either fixedly connected to or detachably connected to the outer wall of the handlebar stem 1. In this example, the positioning ring 4 and the handlebar stem 1 can be fixedly connected by welding or by a clamp, thereby allowing for height adjustment of the handlebar stem 1.

[0032] Example 2: As shown in the figure, this utility model includes a front fork sleeve 2 and a handlebar stem 1. The handlebar stem 1 is inserted into the front fork sleeve 2 and is fastened to the front fork sleeve 2 by a fastening positioning structure. The fastening positioning structure includes an anti-rotation positioning component and a fastener disposed between the front fork sleeve 2 and the handlebar stem 1. The anti-rotation positioning component can prevent the handlebar stem 1 and the front fork sleeve 2 from rotating circumferentially, and the fastener can lock the handlebar stem 1 into the front fork sleeve 2.

[0033] The fasteners can be used to coaxially lock the fork sleeve 2 and the handlebar stem 1 using the fastening method described in the background art of this application. Those skilled in the art can refer to the fastening structure of the fork sleeve 2 and the handlebar stem 1 in the prior art to understand the locking principle of the fasteners in this application, so it will not be elaborated in this solution. In this example, the preferred implementation structure of the fastener is described in the background art as "inserting the handlebar stem 1 into the fork sleeve 2 (usually a straight steel fork), and using a wedge or expansion block mechanism to convert the axial force of the bolt into radial friction force, so that it is tightly connected with the fork sleeve 2". Preferably, the fastener secures the handlebar stem 1 to the fork sleeve 2 via a threaded connection. In this example, the fastener includes a fastening bolt 7 and a beveled fastening head 6. The end of the fastening bolt 7 is rotatably connected to the end of the handlebar stem 1, and the middle of the fastening bolt 7 is located inside the handlebar stem 1. The other end of the fastening bolt 7 is threadedly connected to the beveled fastening head 6. By rotating the fastening bolt 7, the beveled fastening head 6 is brought into tight contact with the interior of the fork sleeve 2. Specifically, both the tail end of the handlebar stem 1 and the end face of the beveled fastening head 6 are beveled structures, which are used to cause the beveled fastening head 6 to undergo radial displacement and come into tight contact with the inner wall of the fork sleeve 2. During the tightening of the fastening bolt 7, the beveled fastening head 6 will undergo radial displacement due to the aforementioned beveled structure, supporting the inner wall of the fork sleeve 2, thereby locking the handlebar stem 1.

[0034] In summary, this application, through the design of an anti-rotation positioning component at the connection between the handlebar stem and the fork sleeve, effectively eliminates the potential risk of relative rotation between the stem and the fork sleeve, ensuring that the handlebars and the front wheel always maintain the same direction, avoiding loss of steering control due to loosening or deviation, and significantly improving the safety, reliability, and durability of the steering system.

[0035] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A frame stem mounting positioning structure comprising a front fork sleeve (2) and a handlebar stem pipe (1), characterized in that, The handlebar stem (1) is inserted into the fork sleeve (2) and is securely connected to the fork sleeve (2) by a fastening and positioning structure. The fastening and positioning structure includes an anti-rotation positioning component and a fastener disposed between the front fork sleeve (2) and the handlebar stem (1). The anti-rotation positioning component can prevent the handlebar stem (1) and the front fork sleeve (2) from rotating circumferentially, and the fastener can lock the handlebar stem (1) into the front fork sleeve (2).

2. The frame stem mounting and positioning structure according to claim 1, characterized in that, The anti-rotation positioning component includes a positioning pin (5) and a positioning groove (3) respectively provided on the handlebar stem (1) and the fork sleeve (2).

3. The frame stem mounting and positioning structure according to claim 2, characterized in that, The positioning pin (5) is set on the handlebar stem (1), and the positioning groove (3) is set at the end of the fork sleeve (2). When the handlebar stem (1) is securely connected to the fork sleeve (2), the positioning pin (5) is placed in the positioning groove (3) of the fork sleeve (2).

4. The frame stem mounting and positioning structure according to claim 3, characterized in that, The positioning pin (5) is fixedly connected to the positioning ring (4), which is located on the outer side wall of the handlebar stem (1).

5. The frame stem mounting and positioning structure according to claim 4, characterized in that, The positioning ring (4) is fixedly connected to or detachably connected to the outer wall of the handlebar stem (1).

6. The frame stem mounting and positioning structure according to any one of claims 3-5, characterized in that, Two positioning pins (5) are arranged opposite each other, and two positioning slots (3) are arranged opposite each other.

7. The frame stem mounting and positioning structure according to claim 1, characterized in that, The fasteners achieve a secure connection between the handlebar stem (1) and the fork sleeve (2) through threaded fastening.

8. The frame stem mounting and positioning structure according to claim 7, characterized in that, The fasteners include fastening bolts (7) and beveled fastening heads (6). The end of the fastening bolt (7) is rotatably connected to the end of the handlebar stem (1). The middle part of the fastening bolt (7) is located inside the handlebar stem (1). The other end of the fastening bolt (7) is threadedly connected to the beveled fastening head (6). By rotating the fastening bolt (7), the beveled fastening head (6) is tightly abutted against the inside of the fork sleeve (2).

9. The frame stem mounting and positioning structure according to claim 8, characterized in that, The tail end of the handlebar stem (1) and the end face of the inclined fastening head (6) are both inclined structures, which are used to make the inclined fastening head (6) generate radial displacement and closely abut against the inner wall of the fork sleeve (2).

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