Bicycle handlebar stem assembly
By introducing a protective cover and adjustment mechanism into the bicycle stem assembly, the problem of rainwater ingress caused by exposed screw heads was solved, resulting in reduced corrosion and improved aesthetics.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUXI XINQI INTELLIGENT TECHNOLOGY CO LTD
- Filing Date
- 2025-08-11
- Publication Date
- 2026-05-19
AI Technical Summary
In existing bicycle handlebar structures, the head of the adjusting screw is exposed, causing rainwater to enter the front fork seat tube, resulting in corrosion and affecting handling safety and aesthetics.
A bicycle stem assembly was designed, comprising a protective cover and an adjustment mechanism. The protective cover covers the screw head, and the distance between the left and right pressure blocks is adjusted by adjusting the bolt to achieve precise control of the gap. The protective cover is also fixed in the receiving groove to prevent rainwater from entering.
It effectively prevents rainwater from entering the fork riser, reduces rust, improves handling safety and aesthetics, and avoids the safety hazard of exposed screw heads.
Smart Images
Figure CN224256857U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of bicycle technology, and in particular to bicycle stem components. Background Technology
[0002] In the bicycle handlebar structure, the stem is fixed to the top of the fork seat tube, and the handlebars extend to both ends of the stem. When the rider turns the handlebars, the stem can drive the fork seat tube and the fork to rotate synchronously, thus achieving steering.
[0003] The fork seat tube and the frame head tube are connected by the headset. The headset, as the steering hub, consists of an upper headset, a lower headset, and internal bearings. The precision of its fit with the fork seat tube and the frame head tube directly determines steering stability. Excessive clearance between the fork seat tube and the headset can cause the front of the bike to wobble during riding, affecting handling safety; insufficient clearance will increase rotational resistance and cause steering jamming.
[0004] To achieve precise adjustment of the clearance, the tightness is essentially adjusted by changing the relative distance between the upper and lower headsets. A typical bicycle headstock structure is as follows: the stem is mounted on the outer wall of the fork seat tube, the lower headset is fixedly connected to the fork seat tube, and the upper headset is positioned above the lower headset. A sunflower nut is embedded inside the fork seat tube; its petals expand elastically and fit tightly against the fork seat tube wall to form a fixed base. A pressure cap is located above the headset, which mates with the upper headset. A screw passes through the pressure cap and is threaded into the sunflower nut. When the screw is tightened, the pressure cap applies downward pressure, pushing the upper headset closer to the lower headset, reducing the clearance between them. When the screw is loosened, the pressure is released, and the clearance between the upper and lower headsets increases accordingly. Therefore, by adjusting the axial pressure of the pressure cap on the headset bearings, precise control of the clearance is achieved; this is the core function of the adjusting screw.
[0005] In the prior art, such as the quick-release device for bicycle handlebar gaskets disclosed in Chinese Patent Application No. 202122006675.5 and the rotatable bicycle stem assembly disclosed in 201310548783.2, the heads of the adjusting screws used to adjust the clearance are directly facing upwards and exposed. Since the upper side of the handlebar is a high-frequency part that users pay attention to visually, the exposed screw heads will disrupt the overall harmony of the front of the bicycle, making the bicycle unsightly. Moreover, with the exposed screw heads facing upwards, rainwater can easily enter, which can easily cause corrosion of related parts and affect subsequent clearance adjustment operations. Utility Model Content
[0006] To address the aforementioned technical problems, the bicycle stem assembly provided by this utility model can reduce the amount of rainwater entering the fork stem tube from the screw, thereby reducing the phenomenon of corrosion inside the fork stem tube.
[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0008] The bicycle stem assembly provided by this utility model includes a stem body and a protective cover; the stem body is provided with an adjustment mechanism; the adjustment mechanism includes a left pressure block, a right pressure block and several adjusting bolts; the left pressure block and the right pressure block are arranged opposite each other; both the left pressure block and the right pressure block are fixed to the stem body; the opposing surfaces of the left pressure block and the right pressure block are semi-cylindrical concave surfaces; the left pressure block has several first adjustment holes; the right pressure block has several second adjustment holes; the holes of the first adjustment holes and the second adjustment holes extend horizontally; the first adjustment holes and the second adjustment holes are respectively aligned; the adjusting bolts can pass through the first adjustment holes and the second adjustment holes simultaneously. The second adjusting hole is fixed; the adjusting bolt can adjust the tightness to change the distance between the left pressure block and the right pressure block; a first receiving groove is opened on the upper right side of the left pressure block; a second receiving groove is opened on the upper left side of the right pressure block; the bottom of the first receiving groove and the second receiving groove are flush with the upper bottom surface of the semi-cylindrical concave surface of the left pressure block; the first receiving groove and the second receiving groove are interconnected; the protective cover can be placed in the first receiving groove and the second receiving groove; the first receiving groove and the second receiving groove can respectively abut against the left and right sides of the protective cover to fix the protective cover; the protective cover can cover the upper opening of the semi-cylindrical concave surface between the left pressure block and the right pressure block.
[0009] The bicycle handlebar assembly provided by this utility model preferably has the upper side of the protective cover being a plane; the openings of the first receiving groove and the second receiving groove are both planes; when the protective cover is fixed in the first receiving groove and the second receiving groove, the upper side of the protective cover is flush with the upper side of the first receiving groove.
[0010] The bicycle stem assembly provided by this utility model preferably includes a connecting block fixed to the lower side of one end of the protective cover; a blocking block fixed to the lower side of the connecting block; the blocking block extending away from the protective cover; the vertical projection of the blocking block onto the bottom surface of the protective cover being outside the protective cover; a gap being left between the stem body and the left and right pressure blocks; the gap allowing the connecting block and the blocking block to pass through; the protective cover covering the gap; a limiting groove being formed on the surface of the stem body facing the left and right pressure blocks; the limiting groove extending horizontally; and the limiting groove matching the shape of the blocking block.
[0011] The bicycle stem assembly provided by this utility model preferably has a bolt head receiving groove provided in the opening of the first adjustment hole facing away from the right pressure block; a nut receiving groove provided in the opening of the second adjustment hole facing away from the left pressure block; the adjustment bolt includes a bolt body and a nut; the head of the bolt body can be received in the bolt head receiving groove; the nut can be received in the nut receiving groove; the bottom of the bolt head receiving groove can restrict the tail of the bolt body from protruding out of the nut receiving groove.
[0012] The above technical solution has the following advantages or beneficial effects:
[0013] This utility model provides a bicycle stem assembly, relating to the field of bicycle technology, including a stem body and a protective cover; the stem body is provided with an adjustment mechanism; the adjustment mechanism includes a left pressure block, a right pressure block and several adjustment bolts; the left pressure block and the right pressure block are arranged opposite each other; both the left pressure block and the right pressure block are fixed to the stem body; the opposing surfaces of the left pressure block and the right pressure block are semi-cylindrical concave surfaces; the left pressure block has several first adjustment holes; the right pressure block has several second adjustment holes; the holes of the first adjustment holes and the second adjustment holes extend horizontally; the first adjustment holes and the second adjustment holes are respectively aligned; the adjustment bolts can pass through the first and second adjustment holes simultaneously. The adjustment hole and the second adjustment hole are fixed; the adjustment bolt can adjust the tightness to change the distance between the left pressure block and the right pressure block; a first receiving groove is opened on the upper right side of the left pressure block; a second receiving groove is opened on the upper left side of the right pressure block; the bottom of the first receiving groove and the second receiving groove are flush with the upper bottom surface of the semi-cylindrical concave surface of the left pressure block; the first receiving groove and the second receiving groove are interconnected; the protective cover can be placed in the first receiving groove and the second receiving groove; the first receiving groove and the second receiving groove can respectively abut against the left and right sides of the protective cover to fix the protective cover; the protective cover can cover the upper opening of the semi-cylindrical concave surface between the left pressure block and the right pressure block. The bicycle stem assembly provided by this utility model solves the problem in the prior art that the screw head for adjusting the tightness of the handlebar rotation faces upward, making it easy for rainwater to enter and causing corrosion of related components. It can reduce the amount of rainwater entering the fork stem tube from the screw, thereby reducing the phenomenon of corrosion inside the fork stem tube. Attached Figure Description
[0014] The present invention, its features, shape, and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference numerals denote like parts throughout the drawings. The drawings are not intentionally drawn to scale; the focus is on illustrating the gist of the invention.
[0015] Figure 1This is a schematic diagram of the overall structure of the bicycle stem assembly provided in Embodiment 1 of this utility model.
[0016] Figure 2 This is a schematic diagram of the structure of the bicycle stem assembly fixed to the rear of the bicycle front fork stem tube according to Embodiment 1 of this utility model.
[0017] Figure 3 This is a schematic diagram of the position and structure of the left pressure block and bolt head receiving groove after the hidden protective cover of the bicycle stem assembly provided in Embodiment 1 of this utility model.
[0018] Figure 4 This is a schematic diagram of the position and structure of the right pressure block and nut receiving groove behind the hidden protective cover of the bicycle stem assembly provided in Embodiment 1 of this utility model.
[0019] Figure 5 This is a schematic diagram of the protective cover structure of the bicycle stem assembly provided in Embodiment 1 of this utility model. Detailed Implementation
[0020] Example 1:
[0021] The bicycle stem assembly provided in Embodiment 1 of this utility model, such as Figures 1 to 5 As shown, the device includes a handlebar stem body 1 and a protective cover 2. An adjustment mechanism 3 is provided on the handlebar stem body 1. The adjustment mechanism 3 includes a left pressure block 31, a right pressure block 32, and several adjusting bolts 33. The left pressure block 31 and the right pressure block 32 are arranged opposite each other. Both the left pressure block 31 and the right pressure block 32 are fixed to the handlebar stem body 1. The opposing surfaces of the left pressure block 31 and the right pressure block 32 are semi-cylindrical concave surfaces. Several first adjustment holes 311 are provided on the left pressure block 31. Several second adjustment holes 321 are provided on the right pressure block 32. The holes of the first adjustment holes 311 and the second adjustment holes 321 extend horizontally. The first adjustment holes 311 and the second adjustment holes 321 are aligned. The adjusting bolts 33 can pass through both the first adjustment holes 311 and the second adjustment holes 321 simultaneously. The adjusting hole 321 is fixed; the adjusting bolt 33 can adjust the tightness to change the distance between the left pressure block 31 and the right pressure block 32; a first receiving groove 312 is opened on the upper right side of the left pressure block 31; a second receiving groove 322 is opened on the upper left side of the right pressure block 32; the bottom of the first receiving groove 312 and the second receiving groove 322 are flush with the upper bottom surface of the semi-cylindrical concave surface; the first receiving groove 312 and the second receiving groove 322 are interconnected; the protective cover 2 can be placed in the first receiving groove 312 and the second receiving groove 322; the first receiving groove 312 and the second receiving groove 322 can be pressed against the left and right sides of the protective cover 2 respectively to fix the protective cover 2; the protective cover 2 can cover the upper opening of the semi-cylindrical concave surface between the left pressure block 31 and the right pressure block 32.
[0022] In this embodiment, the bicycle stem assembly is used as a structural component of the bicycle as a whole. The semi-cylindrical concave surfaces between the left pressure block 31 and the right pressure block 32 respectively abut against both sides of the (bicycle) fork stem tube. The distance between the left pressure block 31 and the right pressure block 32 is adjusted by controlling the adjusting bolt 33. Specifically, the adjusting bolt 33 passes through the first adjusting hole 311 and the second adjusting hole 321. Using the limiting structures at both ends of the adjusting bolt 33 (the head of the bolt body 331 and the nut 332, detailed below), it compresses the ports of the first adjusting hole 311 and the second adjusting hole 321, thereby adjusting the distance between the left pressure block 31 and the right pressure block 32 along the axial direction of the bolt body 331, thus compressing the fork stem tube and achieving the adjustment of the distance between the stem body 1 and the bicycle stem tube. The assembly of the vehicle differs from the prior art in that the top of the left pressure block 31 and the right pressure block 32 in this embodiment is improved. The first receiving groove 312 and the second receiving groove 322 can be combined into a space for placing the protective cover 2. By adjusting the distance between the left pressure block 31 and the right pressure block 32, the protective cover 2 is squeezed by the side walls of the first receiving groove 312 and the second receiving groove 322, thereby fixing the protective cover 2. Since the protective cover 2 is fixed on the upper side of the semi-cylindrical concave surface formed by the left pressure block 31 and the right pressure block 32, the protective cover 2 can block the front fork stem tube between the left pressure block 31 and the right pressure block 32 from above, thereby blocking the screws on the upper part of the front fork stem tube, thereby reducing the situation where rainwater falls into the front fork stem tube and causes corrosion of the internal components.
[0023] The bicycle stem assembly provided in Embodiment 1 of this utility model solves the problem in the prior art where the screw head for adjusting the handlebar rotation tension faces upwards, making it easy for rainwater to enter and cause corrosion of related components. It can reduce the amount of rainwater entering the fork stem tube from the screw, thereby reducing the phenomenon of corrosion inside the fork stem tube.
[0024] To ensure the protective cover 2 maintains an aesthetically pleasing appearance when fitted onto the left and right pressure blocks 31 and 32, as a preferred structure in this embodiment, the upper side of the protective cover 2 is flat; the openings of the first receiving groove 312 and the second receiving groove 322 are both flat; when the protective cover 2 is fixed within the first and second receiving grooves 312 and 322, the upper side of the protective cover 2 is flush with the upper side of the first receiving groove 312. The upper side of the protective cover 2 can be perfectly flush with the upper sides of the left and right pressure blocks 31 and 32, avoiding any visual abruptness caused by the protective cover 2 protruding or recessing from the surfaces of the left and right pressure blocks 31 and 32, thus creating a continuous and flat top for the assembly. The flush structure also prevents the formation of steps between the protective cover 2 and the left and right pressure blocks 31 and 32, and reduces dust accumulation in the gaps.
[0025] Since bicycles experience bumps during travel, to prevent the protective cover 2 from bouncing up and down and falling off the stem assembly, as a preferred solution in this embodiment, a connecting block 21 is fixed to the lower side of one end of the protective cover 2; a blocking block 22 is fixed to the lower side of the connecting block 21; the blocking block 22 extends away from the protective cover 2; the vertical projection of the blocking block 22 on the bottom surface of the protective cover 2 is outside the protective cover 2; a gap is left between the stem body 1 and the left pressure block 31 and the right pressure block 32; the gap allows the connecting block 21 and the blocking block 22 to pass through; the protective cover 2 can cover the gap; a limiting groove 11 is opened on the surface of the stem body 1 facing the left pressure block 31 and the right pressure block 32; the limiting groove 11 extends horizontally; the limiting groove 11 matches the shape of the blocking block 22. The shape of the blocking block 22 matches that of the limiting groove 11, and the blocking block 22 extends away from the protective cover 2. The blocking block 22 passes through the gap between the stem body 1 and the left pressure block 31 and the right pressure block 32, and finally the blocking block 22 is stuck into the limiting groove 11. At this time, the blocking block 22 is restricted by the limiting groove 11. The upper side wall of the limiting groove 11 will restrict the blocking block 22 from detaching from the vertical. When the user needs to open the protective cover 2 to adjust the screws under the protective cover 2, he can lift the end of the protective cover 2 that is away from the blocking block 22, and then pull it out horizontally along the depth direction of the limiting groove 11, so that the blocking block 22 is detached from the limiting groove 11. Then, the protective cover 2 is moved vertically upward to complete the disassembly operation of the protective cover 2.
[0026] To avoid the end of the bolt body 331 being exposed and affecting aesthetics, in this embodiment, the opening of the first adjusting hole 311 facing away from the right pressure block 32 is provided with a bolt head receiving groove 3111; the opening of the second adjusting hole 321 facing away from the left pressure block 31 is provided with a nut receiving groove 3211; the adjusting bolt 33 includes a bolt body 331 and a nut 332; the head of the bolt body 331 can be accommodated in the bolt head receiving groove 3111; the nut 332 can be accommodated in the nut receiving groove 3211; the bottom of the bolt head receiving groove 3111 can restrict the tail of the bolt body 331 from passing through the nut receiving groove 3211. In this embodiment, the bolt head receiving groove 3111 and the nut receiving groove 3211 respectively embed the bolt body 331 head and nut 332 into the interior of the left pressure block 31 and the right pressure block 32, avoiding protrusion from the surface of the left pressure block 31 and the right pressure block 32. This improves the aesthetics of the stem assembly and also prevents the bolt body 331 head or nut 332 from being exposed and snagging on the user's body, clothing or other objects during riding, thereby reducing safety hazards.
[0027] In summary, this utility model provides a bicycle stem assembly, relating to the field of bicycle technology, including a stem body and a protective cover; the stem body is provided with an adjustment mechanism; the adjustment mechanism includes a left pressure block, a right pressure block, and several adjustment bolts; the left pressure block and the right pressure block are arranged opposite each other; both the left pressure block and the right pressure block are fixed to the stem body; the opposing surfaces of the left pressure block and the right pressure block are semi-cylindrical concave surfaces; the left pressure block has several first adjustment holes; the right pressure block has several second adjustment holes; the holes of the first adjustment holes and the second adjustment holes extend horizontally; the first adjustment holes and the second adjustment holes are respectively aligned; the adjustment bolts can pass through simultaneously. The first and second adjustment holes are fixed; the adjustment bolt can adjust the tightness to change the distance between the left and right pressure blocks; a first receiving groove is provided on the upper right side of the left pressure block; a second receiving groove is provided on the upper left side of the right pressure block; the bottom of the first and second receiving grooves is flush with the upper bottom surface of the semi-cylindrical concave surface; the first and second receiving grooves are interconnected; the protective cover can be placed in the first and second receiving grooves; the first and second receiving grooves can respectively abut against the left and right sides of the protective cover to fix the protective cover; the protective cover can cover the upper opening of the semi-cylindrical concave surface between the left and right pressure blocks. The bicycle stem assembly provided by this utility model solves the problem in the prior art where the screw head for adjusting the handlebar rotation tension faces upward, allowing rainwater to easily enter and causing corrosion of related components. It can reduce the amount of rainwater entering the fork stem tube from the screw, thereby reducing the phenomenon of corrosion inside the fork stem tube.
[0028] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the contents of the present utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present utility model.
Claims
1. A bicycle stem assembly, characterized in that, This includes the main body and protective cover; The stem body is provided with an adjustment mechanism; the adjustment mechanism includes a left pressure block, a right pressure block and several adjustment bolts; The left pressure block and the right pressure block are arranged opposite each other; both the left pressure block and the right pressure block are fixed to the handlebar body; The opposing surfaces of the left and right pressure blocks are both semi-cylindrical concave surfaces; The left pressure block has several first adjustment holes; the right pressure block has several second adjustment holes. The first adjusting hole and the second adjusting hole both extend horizontally; the first adjusting hole and the second adjusting hole are respectively aligned. The adjusting bolt can pass through both the first adjusting hole and the second adjusting hole for fixation; the adjusting bolt can adjust the tightness to change the distance between the left pressure block and the right pressure block; The left pressure block has a first receiving groove on the upper right side; the right pressure block has a second receiving groove on the upper left side; the bottom of the first receiving groove and the second receiving groove are flush with the upper bottom surface of the semi-cylindrical concave surface of the left pressure block; the first receiving groove and the second receiving groove are interconnected. The protective cover can be placed in the first receiving groove and the second receiving groove; the first receiving groove and the second receiving groove can respectively abut against the left and right sides of the protective cover to fix the protective cover; the protective cover can cover the upper opening of the semi-cylindrical concave surface between the left pressure block and the right pressure block.
2. The bicycle stem assembly as described in claim 1, characterized in that, The upper side of the protective cover is flat; The openings of both the first and second receiving slots are planar. When the protective cover is fixed in the first receiving groove and the second receiving groove, the upper side of the protective cover is flush with the upper side of the first receiving groove.
3. The bicycle stem assembly as described in claim 1, characterized in that, A connecting block is fixed to the lower side of one end of the protective cover; a blocking block is fixed to the lower side of the connecting block; the blocking block extends away from the protective cover; the vertical projection of the blocking block on the bottom surface of the protective cover is outside the protective cover. A gap is left between the handle body and the left and right pressure blocks; the gap allows the connecting block and the blocking block to pass through; the protective cover can cover the gap. The stem body has a limiting groove on the surface facing the left and right pressure blocks; the limiting groove extends horizontally; the limiting groove matches the shape of the blocking block.
4. The bicycle stem assembly as described in claim 3, characterized in that, The opening of the first adjustment hole facing away from the right pressure block is provided with a bolt head receiving groove; The second adjustment hole has a nut receiving groove in the opening facing away from the left pressure block; The adjusting bolt includes a bolt body and a nut; the head of the bolt body can be accommodated in the bolt head receiving groove; the nut can be accommodated in the nut receiving groove; The bottom of the bolt head receiving groove can restrict the tail of the bolt body from protruding from the nut receiving groove.