CVT speed change mechanism

Abstract

The utility model discloses a CVT speed change mechanism which comprises a driving belt pulley assembly, a driven belt pulley assembly and a driving triangular belt. The driving belt wheel assembly comprises a driving disc and a moving wheel which are coaxially arranged, a box body is arranged on the side, back to the driving disc, of the moving wheel, a moving shaft is slidably connected to the box body in the axial direction of the moving wheel, a fixed shaft is rotationally connected into the box body, and the fixed shaft is in threaded fit with the moving shaft; the box body is connected with a motor used for driving the fixed shaft to rotate, a slope plate is arranged between the movable shaft and the movable wheel, a pulley ball is connected between the slope plate and the movable wheel, and the movable wheel is provided with an inclined sliding groove matched with the pulley ball. According to the scheme, the problem that in the prior art, a CVT speed change mechanism is poor in compatibility is solved.

Description

Technical Field

[0001] The utility model relates to a continuously variable transmission, in particular to a CVT speed changing mechanism. Background Art

[0002] CVT transmission mechanism, also known as continuously variable transmission mechanism or stepless transmission mechanism, is a transmission device that can continuously obtain any transmission ratio within the speed range.

[0003] Chinese patent document CN102109032A discloses an electrically controlled V-belt stepless speed change mechanism, comprising a V-belt; a driving puli disk, having a fixed portion fixed on a support shaft of the driving puli disk and a movable portion capable of axially moving on the support shaft of the driving puli disk, wherein the driving puli disk is driven by the power source; a driven puli disk, connected to the driving puli disk, having a fixed portion fixed on a support shaft of the driven puli disk and a movable portion capable of axially and rotationally moving on the support shaft of the driven puli disk, wherein the driven puli disk is driven by the driving puli disk through the V-belt; a puli disk drive system, connected to the driving puli disk, for providing power to drive the movable portion of the driving puli disk to move axially on the support shaft of the driving puli disk, and the distance of the axial movement is between the fixed portion and the movable portion of the driving puli disk, and The movable part of the driven pullitium reacts to the change in the distance of axial movement of the movable part of the driving pullitium on the driving pullitium support shaft and correspondingly performs axial and rotational movement on the driven pullitium support shaft to change the rotational speed of the driven pullitium; and a transmission case base for accommodating the driving pullitium, the driven pullitium and the pullitium driving system; wherein the pullitium driving system comprises: a bearing seat, which is provided on the movable part of the driving pullitium and slidably connected to the driving pullitium support shaft to which the driving pullitium is attached, and has at least one cam guide groove; a gear case cover, which is connected to the front end portion of the transmission case base; and at least one cam guide device, which is provided between the gear case cover and the cam guide groove of the bearing seat provided on the movable part of the driving pullitium to guide the bearing seat provided on the movable part of the driving pullitium to make axial movement. The electronically controlled V-belt continuously variable transmission mechanism includes a transmission case base cover engaged with the transmission case base to cover the driving pullites and the driven pullites; the pullites drive system includes: a motor for providing power; a gear system disposed between the motor and the driving pullites, for transmitting the power output by the motor to the movable portion of the driving pullites, and having a lead screw connected to a bearing seat disposed on the movable portion of the driving pullites; and a sealing unit disposed between the gear case cover and the bearing seat disposed on the movable portion of the driving pullites, for preventing the gear system, which adopts wet lubrication, from leaking lubricating oil.

[0004] In this prior art, the motor directly drives the outer lead screw and the inner lead screw through the gear mechanism to drive the sliding pulley to move. However, due to the fast response speed of the motor, it is easy to cause the transmission ratio of the speed change mechanism to switch too quickly and generate power transmission fluctuations, thereby reducing the smooth speed change performance of the speed change mechanism and making it difficult for the speed change mechanism to meet conventional power transmission requirements; and the speed change mechanism needs to be adjusted by the motor all the time during use, which increases the complexity of the use of the speed change mechanism and thus increases the difficulty of use. Utility Model Content

[0005] The purpose of the utility model is to provide a CVT transmission mechanism to solve the problem of poor compatibility of the CVT transmission mechanism in the prior art.

[0006] In order to achieve the above-mentioned purpose, the basic scheme of the present utility model provides a CVT transmission mechanism, including a driving pulley assembly, a driven pulley assembly and a driving V-belt; the driving pulley assembly includes a coaxially arranged driving disc and a moving wheel, and a box is provided on the side of the moving wheel facing away from the driving disc, and the box is connected to a moving shaft along the axial direction of the moving wheel, and a fixed shaft is rotatably connected to the box, and the fixed shaft is threadedly engaged with the moving shaft, and the box is connected to a motor for driving the fixed shaft to rotate, and a ramp plate is provided between the moving shaft and the moving wheel, and a puli bead is connected between the ramp plate and the moving wheel, and the moving wheel is provided with an inclined slide groove that cooperates with the puli bead.

[0007] The beneficial effects of this basic solution are as follows: by utilizing a motor to control the fixed and movable shafts to adjust the force between the ramp plate and the puli bead, thereby changing the force and positional relationship between the movable wheel and the drive V-belt, this solution allows the CVT transmission mechanism to better meet the requirements of sudden changes in power demand (such as during starting and acceleration), while also ensuring smoother speed adjustments and less prone to power fluctuations. When the motor is not in use, the CVT transmission mechanism can perform regular adjustments via the puli bead to meet conventional power transmission requirements. Compared to existing technologies, the CVT transmission mechanism of this solution can accommodate multiple power requirements, improving compatibility.

[0008] Preferably, a slider is connected between the ramp plate and the moving wheel and slides along the axial direction of the moving wheel. Such an arrangement is beneficial to avoiding sliding wear of the ramp plate and increasing the stability of the ramp plate, thereby improving structural reliability.

[0009] Preferably, the movable shaft and the ramp plate are rotatably engaged with each other via a deep groove ball bearing. This arrangement is beneficial for reducing wear of the ramp plate, thereby improving structural reliability.

[0010] Preferably, the fixed shaft and the motor are connected via a gear transmission mechanism, which is arranged inside the box. This arrangement facilitates lubrication of the gear transmission mechanism, thereby reducing wear and tear and further reducing maintenance costs.

[0011] Preferably, an oil seal is provided at the mating surface between the movable shaft and the housing. This arrangement is helpful in preventing the lubricating oil in the housing from flowing out from the mating surface between the movable shaft and the housing and affecting the use of the speed change mechanism.

[0012] Preferably, a support bearing is connected between the outer side of the fixed shaft and the box body. With such an arrangement, the fixed shaft is directly positioned outside the box body, thereby facilitating the assembly operation of the fixed shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of an embodiment of a CVT transmission mechanism of the present utility model;

[0014] Figure 2 for Figure 1 Schematic diagram of the middle driving pulley assembly;

[0015] Figure 3 for Figure 1 Schematic diagram of the driven pulley assembly. DETAILED DESCRIPTION

[0016] The following is further described in detail through specific implementation methods:

[0017] The figure marks in the drawings of the specification include: driving disk 1, moving wheel 2, driving V-belt 3, box body 4, displacement sensor 5, motor 6, fixed disk shaft assembly 7, moving disk shaft assembly 8, slider 9, ramp plate 10, deep groove ball bearing 11, support bearing 12, crankshaft 13, moving shaft 14, fixed shaft 15, Pulley bead 16, inclined slide 17, oil seal 18, gear transmission mechanism 19, speed regulating spring 20, and driving main shaft 21.

[0018] The embodiment is basically as shown in the attached Figure 1 、 Figure 2 and Figure 3As shown: A CVT transmission mechanism includes a driving pulley assembly, a driven pulley assembly and a driving V-belt 3, wherein the driving V-belt 3 is connected between the driving pulley assembly and the driven pulley assembly. The driving pulley assembly includes a coaxially arranged drive disc 1 and a moving wheel 2. In this embodiment, a ramp plate 10 is provided between the moving shaft 14 and the moving wheel 2, and a bead 16 is connected between the ramp plate 10 and the moving wheel 2. The moving wheel 2 is provided with an inclined groove 17 that cooperates with the bead 16. The bead 16 is confined within the inclined groove 17 under the action of the ramp plate 10. When the moving wheel 2 rotates, the bead 16 can overcome the force of the ramp plate 10 and move radially along the moving wheel 2 according to the speed of the moving wheel 2. A slider 9 is connected between the ramp plate 10 and the moving wheel 2, which slides along the axial direction of the moving wheel 2, so that the ramp plate 10 and the moving wheel 2 are slidably matched through the slider 9, thereby reducing the problem of performance degradation of the ramp plate 10 due to wear. In this embodiment, the movable shaft 14 and the ramp plate 10 are rotatably engaged via the deep groove ball bearing 11 , so that the movable shaft 14 and the ramp plate 10 can rotate relative to each other while transmitting a large thrust, thereby reducing frictional resistance.

[0019] In this embodiment, a housing 4 is provided on the side of the ramp plate 10 facing away from the moving wheel 2. The housing 4 is connected to a moving shaft 14 in a sliding manner along the axial direction of the moving wheel 2. A fixed shaft 15 is rotatably connected inside the housing 4. The fixed shaft 15 is threadedly engaged with the moving shaft 14, so that the moving shaft 14 can be driven to move axially by the rotation of the fixed shaft 15. In this embodiment, a support bearing 12 is connected between the outer side of the fixed shaft 15 and the housing 4, so that the housing 4 supports and positions the fixed shaft 15 through the support bearing 12. An oil seal 18 is provided at the mating surface between the moving shaft 14 and the housing 4. The housing 4 is connected to a motor 6 for driving the fixed shaft 15 to rotate. Preferably, the fixed shaft 15 and the motor 6 are connected by a gear transmission mechanism 19, and the gear transmission mechanism 19 is arranged inside the housing 4. Specifically, the motor 6 and the fixed shaft 15 are connected by a two-stage reduction gear transmission mechanism 19. In this embodiment, a displacement sensor 5 for monitoring the movement displacement of the moving wheel 2 is installed on the box body 4. The displacement sensor 5 is electrically connected to the controller of the motor 6, thereby facilitating better implementation of automated operation of the motor 6 control.

[0020] In this embodiment, the driven pulley assembly includes a coaxially arranged fixed disc shaft assembly 7 and a movable disc shaft assembly 8. The fixed disc shaft assembly 7 is connected to a speed regulating spring 20 for driving the movable disc shaft assembly 8 to move axially, so that the movable disc shaft assembly 8 and the fixed disc shaft assembly 7 can clamp the driving V-belt 3 under the elastic force of the speed regulating spring 20.

[0021] The specific implementation process is as follows: During use, the driving pulley assembly is mounted on the crankshaft 13, and the driven pulley assembly is mounted on the drive spindle 21, so that the power of the crankshaft 13 is transmitted to the drive spindle 21 through the CVT transmission mechanism. Taking a motorcycle equipped with a CVT transmission mechanism as an example, when the motorcycle starts, the fixed shaft 15 is rotated by controlling the motor 6. The fixed shaft 15 drives the movable shaft 14 in a direction away from the ramp plate 10. The rotation of the movable wheel 2 drives the pulley 16, which reduces the pressure on the drive V-belt 3. This prolongs the time that the CVT transmission mechanism is in a high transmission ratio state, thereby causing the driven pulley to output a large driving force through the drive spindle 21 and maintain it for a long time, allowing the motorcycle to overcome greater resistance and increase speed as quickly as possible, achieving a quick start. When the vehicle speed increases, the ramp plate 10 is returned to its initial position by controlling the motor 6, returning the CVT transmission mechanism to normal use. When the vehicle speed needs to be increased as quickly as possible during driving, the fixed shaft 15 is controlled by the motor 6 to drive the movable shaft 14 toward the ramp plate 10, so that the ramp plate 10 squeezes the bead 16. Under the squeezing action of the ramp plate 10, the bead 16 moves toward the center of the moving wheel 2, and due to the centrifugal force, the bead 16 moves away from the center of the moving wheel 2, thereby causing the moving wheel 2 to squeeze the drive V-belt 3, causing the transmission ratio of the CVT transmission mechanism to change to a small transmission ratio state, thereby achieving a faster increase in vehicle speed. After the vehicle speed increase is completed, the ramp plate 10 is controlled by the motor 6 to return to its initial position, so that the CVT transmission mechanism returns to its normal use state. By adopting this solution, the transmission ratio of the CVT transmission mechanism can be adjusted as needed to meet different power requirements.

[0022] The above description is merely an embodiment of the present invention. The well-known specific structures and characteristics of the scheme are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention. These modifications and improvements should also be considered within the scope of protection of the present invention and will not affect the effectiveness of the implementation of the present invention or the practical application of the patent.

Claims

1. A CVT transmission mechanism, comprising a driving pulley assembly, a driven pulley assembly, and a driving V-belt; the driving pulley assembly comprises a coaxially arranged drive disc and a movable pulley, a housing being provided on the side of the movable pulley facing away from the driving disc, the housing being slidably connected to a movable shaft along the axial direction of the movable pulley, a fixed shaft being rotatably connected to the housing, the fixed shaft being threadedly engaged with the movable shaft, and the housing being connected to a motor for driving the fixed shaft to rotate, characterized in that: A ramp plate is provided between the moving shaft and the moving wheel, a puli bead is connected between the ramp plate and the moving wheel, and the moving wheel is provided with an inclined slide matched with the puli bead.

2. A CVT transmission mechanism according to claim 1, characterized in that: A sliding block is connected between the ramp plate and the moving wheel and slides along the axial direction of the moving wheel.

3. The CVT transmission mechanism according to claim 2, characterized in that: The movable shaft and the ramp plate are rotationally matched via a deep groove ball bearing.

4. A CVT transmission mechanism according to claim 3, characterized in that: The fixed shaft and the motor are connected via a gear transmission mechanism, and the gear transmission mechanism is arranged inside the box.

5. The CVT transmission mechanism according to claim 4, characterized in that: An oil seal is provided at the matching surface between the movable shaft and the box body.

6. The CVT transmission mechanism according to claim 5, characterized in that: A support bearing is connected between the outer side of the fixed shaft and the box body.

Images