Two-wheeled tiltable front fork assembly

Abstract

The present invention is a two-wheeled tiltable front fork group suitable for vehicles with more than three wheels. The front fork group uses only one shock absorber, which can prevent fatal swing accidents that are easily caused by traditional vehicles using two shock absorbers, ensuring that electric bicycles, scooters and motorcycles equipped with the two-wheeled tiltable front fork group of the present invention are safer to drive, achieving a shorter braking distance, no spinning when braking, no side sliding when turning, more comfortable shock absorption, and a smoother riding experience when driving over obstacles.

Description

Technical Field The invention relates to a front fork assembly for vehicles with more than three wheels, and more specifically to a two-wheeled side-tilting front fork assembly. Technical Background The present invention is an improved design of Chinese invention application publication number CN 108 657 337 A (hereinafter referred to as Case A), and the application has a progressive technical effect compared to Case A.

[0001] First, the front fork assembly of the application only uses one shock absorber, instead of the structure of the A case which needs to install two shock absorbers. In this way, in addition to the overall structure being simpler, lighter, and more compact, the most outstanding technical effect is that the application can completely avoid the two shock absorbers arranged side by side in the A case which are prone to resonance and cause the disastrous consequences of the vehicle "death swing, loss of direction, and crash". The death swing (Speed Wobble is a century-old problem for traditional high-speed motor vehicles (especially motorcycles). The main reason is that the damping difference of the two parallel shock absorbers on the front fork group used to support the front wheel or the uneven lateral force on the front wheel will cause the front wheel to wobble left and right, causing "death wobble". Although Case A is equipped with two front wheels, unlike traditional (motorcycle) vehicles with only one front wheel, Case A still has two shock absorbers arranged side by side on the left and right. Once resonance occurs, the vibration source will be transmitted to the shoulder frame through the two shock absorber cylinder rods connected to the front fork shoulder frame. Because the two cylinder rods are arranged on the left and right, it is easy to cause the handlebars and the body to shake left and right. In severe cases, death wobble with violent left and right shaking will occur. In contrast, the embodiment of the application only uses one shock absorber. Without two shock absorbers, the possibility of "death wobble" can be absolutely avoided.

[0002] In addition, compared to Case A, since the application has only one shock absorber, space for one shock absorber can be made available, making it easier for the application to further reduce the center distance between the two wheels. If there is a demand for a product with a narrow wheelbase, the center distance between the two front wheels can be further narrowed to meet the design requirements of a narrower product.

[0003] Compared with Case A, the crank pivot of the application moves up and down with the shock absorber, which is different from the design of Case A in which the crank pivot is fixed and cannot move with the shock absorber. Therefore, under the design condition of the same crank length, the front fork group of the application can be free from the influence of the crank length and arbitrarily select the shock absorber stroke to be matched. However, in Case A, the total amplitude of the shock absorption stroke and the roll of the two wheels cannot exceed the effective swing amplitude of the crank, because the crank swing amplitude cannot be greater than 180 degrees, otherwise when it exceeds the maximum turning point of 180 degrees, the crank will be stuck and cannot move normally. Therefore, the shock absorption and roll performance of the vehicle equipped with the front fork group of Case A are restricted by the length and effective swing amplitude of the crank, and its overall product performance, structural design flexibility and manufacturing cost are not as good as those of the application.

[0004] Case A and the application belong to the same applicant. The applicant has personally experienced the shortcomings of Case A. The applicant has also personally tested why Case A should be improved and the effects of the improvements. At the beginning of the design of Case A, it was believed that the death swing of the two front wheels could be avoided by having two front wheel structures that could balance, correct and freely tilt. However, after more than a year since the authorization of Case A, intensive tests and comparisons have confirmed that Case A still has shortcomings. Compared with Case A, the application does have outstanding and significant improvements in technical effects such as avoiding "vehicle death swing", further "simplifying the structure and narrowing the vehicle width" and reducing "product costs". Summary of the invention The present invention is a two-wheeled tiltable front fork assembly, which is suitable for bicycles, motorcycles and scooters, and aims to provide a safer vehicle design, and completely prevent the front fork from being easily damaged by death swing when a traditional two-wheeled or three-wheeled vehicle is traveling at high speed.

[0005] Features and Purposes of the Invention The main features of the invention are: the combined forces of all forces between the two wheels and the ground of the two-wheeled tilting front fork assembly of the invention will eventually be transmitted to a single shock absorber for absorption, buffering and damping to achieve the shock absorption effect. Because of the single shock absorber design, the mutual excitation, interference and resonance between the two shock absorbers used in the traditional design can be avoided, and the death swing (Speed ​​​​swing) of the vehicle front fork assembly can be effectively prevented. Wobble); the secondary feature of the present invention is: the structural arrangement of a single shock absorber provides a simpler structure and a narrower design space for the center distance between the two front wheels, while also reducing the product manufacturing and maintenance costs; the application also proposes an embodiment of a double shock absorber arranged parallel to each other front and back. Although the effect of preventing the front fork from swaying is not as good as the above-mentioned single shock absorber design, it can also significantly reduce the occurrence of front wheel death sway, because the shock absorber is a structural arrangement of parallel to each other front and back. Even if the two shock absorbers are not synchronized, the vibration generated is parallel to the driving direction of the front fork group. This vibration will only cause the handlebars and frame connected to the front fork group to jump up and down, and will not cause the frame to tilt left and right or the handlebars to shake left and right to cause death sway and vehicle out of control. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is an appearance diagram of the front fork assembly of the first embodiment of the present invention

[0007] Figure 2 for Figure 1 The front fork assembly diagram of the first embodiment is shown

[0008] Figure 3 for Figure 1 Exploded view of the front fork assembly of the first embodiment shown

[0009] Figure 4 This is the appearance diagram of the front fork assembly of the second embodiment of the present invention

[0010] Figure 5 for Figure 4 The front fork assembly diagram of the second embodiment shown

[0011] Figure 6 for Figure 5 A cross-sectional view of the front fork assembly of the second embodiment shown

[0012] Figure 7 This is an appearance diagram of the front fork assembly of the third embodiment of the present invention

[0013] Figure 8 for Figure 7 A cross-sectional view of the front fork assembly of the third embodiment shown DETAILED DESCRIPTION The present invention will be further described below in conjunction with the accompanying drawings:

[0014] Figure 1 , Figure 2 and Figure 3 The first embodiment of a two-wheel tiltable front fork assembly in the application is shown. Figure 1 The two-wheeled tiltable front fork assembly (1) is suitable for assembling a left front wheel assembly (2) and a right front wheel assembly (3), and can also be pivotally connected to a head tube (4-1) of a frame (4) of a conventional vehicle and connected to a handlebar (4-2), so that the handlebar (4-2) can be directly operated to drive the entire front fork assembly (1) and the left and right front wheel assemblies (2, 3) to turn synchronously; Figure 2It can be clearly seen that its features also include: a vertical column (5), which can be pivotally connected to the head tube (4-1) of the frame (4) and connected to the handlebar (4-2); a shoulder frame (6), one end of which is connected to the vertical column (5); a crank pivot (7); a straight-tube shock absorber (8) with a damping function commonly used in vehicles, which includes: a cylinder rod (8-1) and a cylinder barrel (8-2), one end of the cylinder rod (8-1) is fixed to the shoulder frame (6), and the other end of the cylinder rod (8-1) penetrates into the inner cavity of the cylinder barrel (8-2) and can slide up and down; an anti-spin guide (9); A connecting bridge (10) connects the anti-rotation guide (9) and the cylinder (8-2) of the shock absorber in parallel and synchronously to prevent the cylinder (8-2) from rotating. One end of the connecting bridge (10) is provided with a fixing portion fixedly connected to the crank pivot (7). One end (a) of the guide (9) is fixedly pivoted on the shoulder frame (6), and the other end (b) of the guide (9) is fixedly pivoted on the connecting bridge (10). When the cylinder (8-2) and the connecting bridge (10) move up and down synchronously, the guide is driven to swing around point d through point b, because a, b, and d are parallel pivot structures. The connecting bridge (10) is not allowed to rotate relative to the shoulder frame (6) on the vertical plane of the axis of the cylinder rod (8-1), thereby achieving the design requirement that the guide cylinder barrel (8-2) and the crank pivot (7) cannot swing; one end of a left crank (11) and a right crank (12) are respectively pivoted to the crank pivot (7) so that they can swing freely, and the other ends of the two cranks can be respectively fixed to the corresponding left front wheel group (2) and right front wheel group (3), and a force-bearing pivot point (13) is respectively provided on the two cranks (11, 12) at an appropriate distance from the pivot center of the crank pivot; a rocker arm group (14) has a central axis The core (14-1) is pivotally connected to the connecting bridge (10) by means of a bracket (14-2) and moves up and down synchronously with the cylinder (8-2) of the shock absorber; the rocker arm assembly (14) can freely swing around the central axis (14-1); the rocker arm assembly (14) is also provided with left and right rocker arms of equal length, and the outer ends of the two rocker arms are respectively provided with a rocker arm pivot point (14-3); a left connecting shaft (15) and a right connecting shaft (16), one end of each of which is flexibly pivotally connected to the corresponding rocker arm pivot point (14-3), and the other end is pivotally connected to the force-bearing pivot points (13) of the two corresponding cranks;When the front wheel on any side is subjected to force or displacement, the crank on that side uses the pivot (7) as a fulcrum and the force-bearing pivot point (13) as an output point to transmit the force or displacement to the rocker arm assembly (14) through the corresponding connecting shaft (15 or 16), and then utilizes the lever action of the equal-length rocker arm to transmit the force or displacement of the front wheel to the other side to achieve the tilting and balancing correction function of the front fork assembly (1). Without considering the shock absorption effect, the frame jump height is halved when the single-side front wheel passes an obstacle. When the vehicle tilts and turns, the grip of the two front wheels is more even, safer, and less likely to slide. The special functional feature of the side tilting front fork assembly (1) is that when any one wheel of the left and right front wheel assemblies is subjected to force alone or both wheels are subjected to force simultaneously, the force on the left and right wheels is transmitted and corrected through the left and right equal-length rocker arms, so that the force on the left and right wheels is kept equally balanced. Finally, the combined force of the left and right front wheels is transmitted to a single shock absorber (8) through the rocker arm pivot point (14-3) for absorption, buffering and damping to achieve a shock absorption effect. The single shock absorber design can avoid the mutual excitation, interference and resonance between the two shock absorbers used in the traditional design, and effectively prevent the vehicle front fork assembly from deadly swinging.

[0015] Figure 2 and Figure 3 The anti-rotation guide (9) shown is a link group with a chain-like structure. The center (d) of the two links is firmly pivoted to allow only the two links to swing freely. One of the links is a fixed link (9-4), one end (a) of which is pivoted to the shoulder frame (6). The other link is a movable link (9-3), one end (b) of which is pivoted to the connecting bridge. The connecting bridge (10) is also used to fix the cylinder barrel (8-2), the rocker arm assembly (14) and the crank pivot (7) to keep them moving synchronously. Therefore, when the cylinder barrel (8-2) is subjected to When the force moves up and down, it will drive the end (b) of the anti-rotation guide (9) to move up and down through point b. Because the other end (a) of the guide (9) is fixedly pivoted on the shoulder frame (6) and cannot move relatively, the guide (9) can prevent the cylinder (8-2) from rotating. It can also ensure that the crank pivot (7) fixed to the cylinder (8-2) and the connecting bridge (10) will not shake, so as to drive the left and right cranks (11, 12) and the front wheels (2, 3) to point stably in the driving direction, which is conducive to the stable driving of the vehicle.

[0016] Figure 4 The figure shows an electric bicycle, in which a front fork assembly (1) is a second embodiment of a two-wheeled tiltable front fork assembly (1) of the application. The front fork assembly (1) can be equipped with left and right front wheels (2, 3), and is pivotally connected to a head tube (4-1) and rotates together with a handlebar (4-2). It also has a rocker arm assembly (14) that can transmit the force and displacement of the crank and the front wheel through left and right connecting shafts (15, 16) to achieve balanced correction of the force and displacement of the two front wheels and a tiltable function; Figure 5 and Figure 6It can be clearly seen that the difference between this embodiment and the first embodiment is that the guide (9) includes: a hollow cylindrical guide cylinder (9-2); an axial guide cylinder rod (9-1), one end (a) of which is fixed to the shoulder frame (6) and keeps the axis of the guide cylinder rod (9-1) parallel to the movement direction of the shock absorber (8), and the other end of the guide cylinder rod (9-1) extends into the hollow cylinder of the guide cylinder (9-2) to guide the guide cylinder (9-2) to move up and down coaxially; a connecting bridge (10), which is fixed to the rocker arm group (14) and rigidly connects the guide cylinder (9-2) and the shock absorber cylinder (8-2) and the crank pivot (7) together to move up and down synchronously, thereby achieving the design requirement that the cylinder (8-2) will not swing perpendicular to its movement direction; looking at the above-mentioned second embodiment, only one shock absorber is used, which can effectively prevent the occurrence of death swing.

[0017] Figure 7 and Figure 8 The third embodiment of the application is shown, in which a front fork assembly (1) is also suitable for assembling two front wheels (2, 3), and comprises: a vertical column (5), a shoulder frame (6), a left crank (12), a right crank (10), a rocker arm assembly (14), a left connecting shaft (15), and a right connecting shaft (16); the difference from the second embodiment is that: two shock absorbers (8, 9) arranged side by side in front and back, each of which is provided with a set of shock absorbing and damping components (8-3) available on the open market between the cylinder barrel (8-2, 9-2) and the cylinder rod (8-1, 9-1), Figure 8 It can be seen that the shock-absorbing and damping assembly (8-3) is composed of a compression spring, a piston rod assembly, a one-way spring damping sleeve and a bolt. In terms of product application, various types of pneumatic and oil-gas mixed shock-absorbing and damping assemblies commonly used in the market can also be used instead; this design of double shock absorbers (8, 9) parallel to the driving direction and arranged front and back can also reduce or avoid the possibility of death swing, that is, there is resonance between the two shock absorbers, and the impact of their vibration on the front fork assembly (1) is an up and down jump parallel to the driving direction rather than a left and right shake, so the third embodiment can also reduce or avoid the occurrence of death swing.

Claims

1. A two-wheeled tiltable front fork assembly (1), suitable for assembling a left front wheel assembly (2) and a right front wheel assembly (3), which is pivotally connected to a head tube (4-1) of a conventional vehicle frame (4) and connected to a handlebar (4-2); wherein the fork assembly is characterized by: It includes: a, a vertical column (5), which can be pivotally connected to the head tube (4-1) of the frame (4) and connected to the handlebar (4-2) to operate the swing of the entire front fork group (1); b, a shoulder frame (6), the upper end of which is fixedly connected to the vertical column (5) so as to keep synchronous rotation; c, a crank pivot (7); d. A straight-tube shock absorber (8) with a damping function, comprising at least: a cylinder rod (8-1) and a cylinder barrel (8-2), wherein the upper end of the cylinder rod (8-1) is fixedly connected to a connection point of the shoulder frame (6), and the other end of the cylinder rod (8-1) penetrates into the inner cavity of the cylinder barrel (8-2) to allow the cylinder barrel (8-2) to slide up and down coaxially; e. an anti-rotation guide (9), a fixed end (a) of which is connected to the shoulder frame (6) to prevent the anti-rotation guide (9) from rotating in a direction perpendicular to the axis of the cylinder rod (8-1); the anti-rotation guide (9) is also provided with a movable end (b); f, a connecting bridge (10), which has a fixed portion fixedly connected to the crank pivot (7), and also has a fixed portion connected to a moving end (b) of the anti-rotation guide (9), the connecting bridge (10) connects the moving end (b) of the anti-rotation guide (9) and the cylinder (8-2) of the shock absorber together to promote synchronous movement of the two and is used to prevent the cylinder (8-2) from rotating in a direction perpendicular to the axis of the cylinder rod (8-1) relative to the shoulder frame (6); g, a left front crank (11) and a right front crank (12), one end of the two cranks being respectively pivotally connected to the crank pivot (7) to swing freely, the other ends (c) of the two cranks being respectively fixed to the corresponding left front wheel assembly (2) and right front wheel assembly (3), and a force-bearing pivot point (13) being respectively provided on the two cranks (11, 12) at an appropriate distance from the pivot point of the crank pivot (7); h, a rocker arm assembly (14), the central axis portion (14-1) of which is pivotally connected to the connecting bridge (10) and moves up and down synchronously with the cylinder barrel (8-2) of the shock absorber, and the rocker arm assembly (14) can freely swing around the central axis portion (14-1), the rocker arm assembly (14) is also provided with left and right rocker arms of equal length, and the outer ends of the two rocker arms are respectively provided with a rocker arm pivot point (14-3); a left connecting shaft (15) and a right connecting shaft (16), one end of each of which is flexibly pivotally connected to the corresponding rocker arm pivot point (14-3), and the other end is pivotally connected to the force-bearing pivot points (13) of the corresponding two cranks; The functional feature of the two-wheeled tiltable front fork assembly (1) is that when any one of the left front wheel assembly (2) and the right front wheel assembly (3) is subjected to force alone or when both front wheel assembly (3) are subjected to force simultaneously, the force is transmitted and corrected via the equal-length left and right rocker arms, so that the forces on the left front wheel assembly (2) and the right front wheel assembly (3) are kept equally balanced, and finally, the combined force of the forces on the left front wheel assembly and the right front wheel assembly is transmitted to the straight-tube shock absorber (8) through the central axis of the rocker arm assembly for absorption, buffering and damping to achieve a shock-absorbing effect.

2. A two-wheeled tiltable front fork assembly according to claim 1, wherein: An anti-rotation guide (9) comprises: a fixed link (9-4), one end (a) of which is hooked to the shoulder frame (6); a movable link (9-3), one end (b) of which is pivotally connected to the connecting bridge (10); the center (d) of the fixed link (9-4) and the movable link (9-3) are pivotally connected together and allow the fixed link (9-4) and the movable link (9-3) to swing freely.

3. A two-wheeled tiltable front fork assembly according to claim 1, wherein an anti-spin guide (9) comprises: a hollow cylindrical guide cylinder (9-2), and a guide cylinder rod (9-1), one end of the guide cylinder rod (9-1) is a fixed end (a) fixed to the shoulder frame (6) and keeps the axis of the guide cylinder rod (9-1) parallel to the movement direction of the shock absorber (8), the other end (b) of the guide cylinder rod (9-1) extends into the hollow cylinder body of the guide cylinder (9-2) to guide the guide cylinder (9-2) to move coaxially up and down, a connecting bridge (10) is fixed to the rocker arm assembly (14) and rigidly connects the guide cylinder (9-2) and the shock absorber cylinder (8-2) and the crank pivot (7) together for synchronous up and down movement.

4. A two-wheeled tiltable front fork assembly according to claim 3, wherein an anti-spin guide (9) which includes a group of shock absorbing and damping components (8-3) of the shock absorber (8) is assembled between the guide cylinder rod (9-1) and the guide cylinder barrel (9-2) to perform a shock absorbing function.

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