A multi-speed ratio belt drive mini-tiller and a control method thereof

Abstract

This invention relates to the field of micro-tiller technology and discloses a multi-speed belt-driven micro-tiller, including an internal combustion engine, a gearbox, and a handlebar frame mounted on a wheeled frame. The internal combustion engine is connected to the gearbox via a tensioning belt drive mechanism. The tensioning belt drive mechanism includes: a belt assembly consisting of a drive pulley, a driven pulley, a first belt, and a second belt; and two tensioning devices, which act on the first and second belts respectively. The drive pulley is mounted on the output shaft of the internal combustion engine, and the driven pulley is mounted on the input shaft of the gearbox. The first and second belts are loosely coupled side-by-side between the drive pulley and the driven pulley, and the drive pulley and the driven pulley are configured with two corresponding sets of different transmission ratios. This micro-tiller enables a single-ratio gearbox to achieve adjustable multi-speed belt drive output, with quick and reliable switching speed. This invention also discloses a control method for the multi-speed belt-driven micro-tiller.

Description

Technical Field

[0001] This invention belongs to the field of micro-tiller technology, and provides a multi-speed ratio belt-driven micro-tiller and its control method. Background Technology

[0002] Mini tillers are agricultural and garden machinery designed for operation in orchards, vegetable gardens, greenhouses, hilly areas, and small plots of land. They have been widely promoted and used. However, the power of current mini tillers is generally provided by internal combustion engines or motors. The internal combustion engine or motor has a power output shaft that extends out of the machine body, and a drive wheel is located on this shaft. For protection and other considerations, belt transmission is used to reduce the impact on the internal combustion engine or motor. The power is then transmitted to the gearbox after the belt is tensioned, thus realizing the engagement and disengagement of power.

[0003] However, existing mechanical structures often use a master and driven wheel with the same transmission ratio and a single tensioner for power transmission. The mechanical speed change can only be achieved by a gearbox. The result is that, on the one hand, the gearbox consists of two parts: a transmission mechanism and a control mechanism. The main function of the transmission mechanism is to change the value and direction of torque and speed, while the main function of the control mechanism is to control the transmission mechanism to change the transmission ratio, that is, to shift gears, so as to change speed and torque. In this case, on a mini-tiller, it is usually necessary to operate a separate control mechanism to achieve the effect of changing mechanical speed. However, the control mechanism is located close to the gearbox, which means that after the operator holds the handlebars of the mini-tiller, there is a certain distance between the operator and the control mechanism, making the speed change not quick enough. On the other hand, the gear ratio of a transmission is limited for a mini-tiller. Using too many gear ratios will inevitably increase the overall structure of the transmission, resulting in an excessively large transmission size and thus increasing the manufacturing cost of the mini-tiller. On the other hand, if too few gear ratios are used, such as a transmission with only forward and reverse gears, although the transmission can be miniaturized, it will not have variable speed and will only have forward and reverse gear switching. Therefore, it will not allow the mini-tiller to adapt well to different working conditions or occasions and meet the possible driving speed and tillage torque. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a multi-speed belt-driven micro-tiller and its control method, in order to solve the problems of insufficient speed switching of mechanical speed and the lack of variable speed in a single-speed gearbox.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a multi-speed belt-driven micro-tiller, including an internal combustion engine, a gearbox, and a handlebar frame mounted on a wheeled frame. The internal combustion engine is connected to the gearbox via a tension belt drive mechanism. The tension belt drive mechanism includes: a belt assembly consisting of a drive pulley, a driven pulley, a first belt, and a second belt; and two tensioning devices, which act on the first belt and the second belt respectively. The drive pulley is mounted on the output shaft of the internal combustion engine, and the driven pulley is mounted on the input shaft of the gearbox. The first belt and the second belt are loosely coupled side-by-side between the drive pulley and the driven pulley, and the drive pulley and the driven pulley are configured to have two corresponding sets of different transmission ratios.

[0007] Optionally, the wheel belt assembly further includes: a first pressure block on the wheel frame and near the driven wheel for pressing against the first belt; a second pressure block on the wheel frame and near the driving wheel for pressing against the second belt; and a belt cover on the wheel frame for covering the driving wheel and the driven wheel.

[0008] Optionally, a single tensioning device consists of a rocker arm, a rotating cylinder, a control line, a tension spring, and a tension wheel. One end of the rocker arm is equipped with a rotating cylinder, and the other end is equipped with a tension wheel for acting on the first belt or the second belt. One end of the tension spring is connected to the rocker arm, and the other end is connected to the control line.

[0009] Optionally, the rotating cylinders on the rocker arms of the two tensioning devices are rotatably connected in series on the same rotating shaft, and a spacer tube is provided on the rotating shaft and located between the two rotating cylinders. The rotating shaft is located on the gearbox housing or the wheel frame.

[0010] Optionally, the control lines of the two tensioning devices are respectively set on the same clutch line seat via a connecting pin at the end opposite to their respective tension springs, and the clutch line seat is located on the wheeled vehicle body.

[0011] Optionally, the tensioner belt drive mechanism also includes: two clutch devices for controlling the control lines of the two tensioning devices respectively. Each clutch device consists of an extension cable and a clutch handle. One end of the extension cable is connected to the control line, and the other end is connected to the clutch handle set on the handrail.

[0012] Optionally, the tensioning pulley belt drive mechanism also includes: an interlocking device for interlocking control of the two tensioning devices, consisting of a pull rope and a pulley, with the pulley rotating on the wheel frame, the pull rope wound around the pulley, and both ends of the pull rope connected to the rocker arms of the two tensioning devices respectively.

[0013] Optionally, the interlocking device also includes a bracket, a pin, and a housing. The pulley rotates on the bracket via the pin, and the housing covers the bracket and the pulley, and is fixed to the wheel frame along with the bracket.

[0014] Optionally, the gearbox has a herringbone structure, consisting of a main gearbox, a front axle gearbox, a rear axle gearbox, and a cutter shaft gearbox. The driven wheel is mounted on the input shaft of the main gearbox, and the output shaft of the main gearbox drives the front axle gearbox, the rear axle gearbox, and the cutter shaft gearbox respectively. The transmission ratio of the front axle gearbox is smaller than that of the rear axle gearbox and the cutter shaft gearbox.

[0015] This invention also discloses a control method for a multi-speed belt drive micro-tiller. The control method for the multi-speed belt drive micro-tiller includes: using two clutch devices to control two tensioning devices to act independently on the belt device, and the individual actions of the two tensioning devices are interlocked by an interlocking device to quickly switch between belt devices with two different transmission ratios, so that the power of the internal combustion engine is transmitted to the gearbox through the belt device to obtain an adjustable multi-speed belt drive output.

[0016] The technical effects of this invention are as follows:

[0017] 1. This mini-tiller enables a single-ratio gearbox to achieve multi-ratio belt drive output. For example, a gearbox with only forward and reverse gears can utilize a belt system with two different gear ratios to transmit power from the internal combustion engine to the gearbox. This transforms the original single forward and reverse gears into two forward and two reverse gears with different speed ratios. Furthermore, the number of belt ratios or gearbox ratios can be increased to provide up to six gears or more, meeting the needs of users in various application scenarios.

[0018] 2. This mini-tiller uses two clutch handles on the handlebar frame to control two tensioning devices that act independently on the tire belt. Simply operating the clutch handles allows for easy and quick switching between the two sets of different transmission ratios of the tire belt, making it very convenient to use.

[0019] 3. This mini-tiller achieves independent belt drive for two sets of belt devices with different transmission ratios by interlocking control through the individual operation of the two tensioning devices. It also avoids interference in the synchronous transmission of the two sets of belt devices with different transmission ratios due to accidental operation such as simultaneously pressing the two clutch levers.

[0020] In summary, this mini-tiller offers adjustable multi-speed belt drive output, features a simple and feasible structure, is quick and easy to operate, and is safe and reliable in operation, making it highly practical.

[0021] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0023] Figure 1 This is a schematic diagram of the overall structure of the multi-speed belt-driven micro-tiller of the present invention;

[0024] Figure 2 for Figure 1 A schematic diagram of the tensioner belt drive mechanism in the middle;

[0025] Figure 3 for Figure 2 A schematic diagram of the tire assembly structure in the middle;

[0026] Figure 4 for Figure 2 A schematic diagram of the tensioning and interlocking devices in the middle;

[0027] Figure 5 for Figure 1 A schematic diagram of the gearbox structure in the image;

[0028] Figure 6 for Figure 1 A schematic diagram of another configuration of the clutch device on the handrail frame;

[0029] Figure 7 This is a schematic diagram of the protective structure applied to the multi-speed belt drive micro-tiller of the present invention;

[0030] Figure label:

[0031] 1-Belt assembly, 11-Driving pulley, 12-Driven pulley, 13-First pressure block, 14-First belt, 15-Second belt, 16-Second pressure block, 17-Belt cover;

[0032] 2-Tensioning device, 21-Rocker arm, 22-Rotating cylinder, 23-Spacer tube, 24-Shaft, 25-Wire seat, 26-Connecting pin, 27-Control wire, 28-Tension spring, 29-Tensioning wheel;

[0033] 3-Interlocking device, 31-Bracket, 32-Pull rope, 33-Pulley, 34-Pin, 35-Housing shell;

[0034] 4-Clutch mechanism, 41-Extension cable, 42-Clutch handle;

[0035] 5-Handrail frame;

[0036] 6-Gearbox, 61-Main gearbox, 62-Front axle gearbox, 63-Rear axle and cutter shaft gearbox;

[0037] 7-Internal combustion engine;

[0038] 8-Wheel frame. Detailed Implementation

[0039] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0040] Example 1

[0041] like Figure 1-4As shown, the multi-ratio belt-driven micro-tiller mentioned in this embodiment mainly consists of a wheeled frame 8 and an internal combustion engine 7, a gearbox 6, and a handlebar frame 5 mounted on the wheeled frame 8. The internal combustion engine 7 is connected to the gearbox 6 via a tension belt drive mechanism, which includes a belt assembly 1, a tensioning device 2, and a clutch device 4. The belt assembly 1 consists of a drive pulley 11, a driven pulley 12, a first belt 14, and a second belt 15. The drive pulley 11 is mounted on the output shaft of the internal combustion engine 7, and the driven pulley 12 is mounted on the input shaft of the gearbox 6. The first belt and the second belt are aligned at an angle. A loosely coupled pair exists between the driving pulley 11 and the driven pulley 12, with the driving pulley 11 and the driven pulley 12 configured to have two corresponding sets of different transmission ratios. Two tensioning devices 2 are configured to act on the first belt 14 and the second belt 15 respectively. Each tensioning device 2 consists of a rocker arm 21, a rotating cylinder 22, a control line 27, a tension spring 28, and a tension wheel 29. One end of the rocker arm 21 is equipped with the rotating cylinder 22, and the other end is equipped with a tension wheel 29 that can act on either the first belt 14 or the second belt 15. One end of the tension spring 28 is connected to the rocker arm 21, and the other end is connected to the control line 28. The two tensioning devices 2 are connected in series, and the rotating cylinders 22 on the rocker arms 21 of the two tensioning devices 2 are all rotatably connected to the same rotating shaft 24, so as to facilitate the compact installation and operation of the two tensioning devices 2; the rotating shaft 24 can be installed on the gearbox 6 housing, and in different examples it can also be installed on the wheel frame 8; the two clutches 4 are respectively installed on the two handles of the armrest frame 5, for single-handed operation of the control lines 27 of the two tensioning devices 2, and each clutch 4 consists of an extension cable 41 and a clutch handle 42, one end of which is connected to the control line 27, and the other end It is connected to the clutch handle 42 installed on the handrail 5. The clutch handle acts as a clutch switch and cooperates with the handle on the handrail 5. That is, the operator can pull or release the extension cable 41 by squeezing the clutch handle and the handrail handle with one hand, thereby operating the control line 27 of a tensioning device 2. This causes the rocker arm 21 of the tensioning device 2 to be pulled, and the tensioning wheel 29 on it to generate tension on the first belt 14 or the second belt 15. This allows the pulley belt device 1 between the internal combustion engine 7 and the gearbox 6 to obtain a certain transmission ratio, thereby enabling the transmission between the three.

[0042] In this embodiment, the wheel belt device 1 further includes a first pressure block 13 on the wheel frame 8 and near the driven wheel 12, which is used to press against the first belt 14, and a second pressure block 16 on the wheel frame 8 and near the driving wheel 11, which is used to press against the second belt 15. Through the design structure of the first pressure block 13 and the second pressure block 16, the first belt 14 and the second belt 15, which are loosely fitted between the driving wheel 11 and the driven wheel 12, can be tensioned by their respective tensioning devices 2 to ensure that the first belt 14 and the second belt 15 operate reliably and do not deviate, thereby making the wheel belt device 1 operate smoothly so as to transmit the power output of the internal combustion engine 7 to the gearbox 6.

[0043] In this embodiment, a spacer tube 23 is provided on the rotating shaft 24 and between the two rotating cylinders 22 to give the two rocker arms 21 a certain distance, thereby allowing the two tensioning devices 2 to better correspond to the first belt 14 and the second belt 15 respectively. In addition, the control lines 27 of the two tensioning devices 2 are respectively mounted on the same clutch cable seat 25 through a connecting pin 26 at the end opposite to their respective tension springs 28, and the clutch cable seat is fixedly mounted on the wheeled vehicle body 8 for uniform installation.

[0044] like Figure 5 As shown, the gearbox 6 in this embodiment adopts a herringbone structure, which consists of a main gearbox 61, a front axle gearbox 62, and a rear axle and cutter shaft gearbox 63. The input shaft of the main gearbox 61 is equipped with a driven wheel 12. The output shaft of the main gearbox 61 transmits power to the front axle gearbox 62, the rear axle and cutter shaft gearbox 63 respectively. The transmission ratio of the front axle gearbox 62 is smaller than that of the rear axle and cutter shaft gearbox 63, so that the rear axle and cutter shaft gearbox 63 has a greater torque relative to the front axle gearbox 62, which is used for the movement of the tiller and the operation of the cutter shaft.

[0045] like Figure 7 As shown in this embodiment, the belt cover 17 on the wheel frame 8 is used to cover the drive wheel 11, the driven wheel 12 and the belt on it, and serves the purpose of safety protection.

[0046] In this embodiment, the tension spring 28 can also be replaced by a component such as hydraulic pressure to generate tension, which can also achieve the purpose of selecting different tensioning pulleys to tighten the belt, so that belts with different transmission ratios can be pressed on the working pulley with appropriate pressure, thereby achieving the effect of quickly switching mechanical speed.

[0047] Specifically, two sets of belt devices 1 with different transmission ratios are installed between the output shaft of the internal combustion engine 7 and the input shaft of the gearbox 6. That is, two belts (first belt 14 and second belt 15) are installed on two sets of pulleys (driving pulley 11 and driven pulley 12). Two tensioning pulleys 29 are installed sequentially at corresponding positions on the outer edges of the two belts. The two tensioning pulleys 29 are rotatably mounted on two rocker arms 21 through rolling bearings. The ends of the two rocker arms 21 away from the tensioning pulleys 29 are rotatably mounted on the same rotating shaft 24, which is fixedly mounted on the gearbox 6. Two rocker arms have three fixed point holes at different positions near the pivot point to adjust the installation position. One end of each of the two tension springs 28 is connected to the two rocker arms 21 through one of the fixed point holes, and the other end is connected to the control line 27. A clutch cable seat 25 is fixedly installed on the wheel frame 8. The clutch cable seat 25 has multiple mounting slots corresponding to the positions of the two tension springs 28. The control line 27 passes through the corresponding mounting slots and is telescopically installed on the clutch cable seat 25 through the connecting pin 26. The end of the control line 27 away from the tension springs 28 is connected to the clutch handle 42 through the extension cable 41. The clutch handle 42 is installed on the handle of the armrest 5. The clutch handle of the clutch device 4 is rotatably mounted with a pull rope box through a pin. The pull rope box is fixedly installed on the armrest 5 and the armrest 5 is fixedly installed on the wheel frame 8.

[0048] Using the above solution, this mini-tiller enables a single-ratio gearbox to achieve multi-ratio belt drive output. For example, a gearbox with only forward and reverse gears can utilize two belt systems with different gear ratios to transmit power from the internal combustion engine to the gearbox. This transforms the gearbox's original single forward and reverse gears into two forward and two reverse gears with different speed ratios. Furthermore, the mini-tiller uses two clutch levers mounted on the handlebars to control two tensioning devices that act independently on the belt system. Simply operating the clutch levers allows for easy and quick switching between the two different gear ratios of the belt system, making it extremely convenient to use.

[0049] Furthermore, those skilled in the art should understand that, according to the actual application needs of users, the transmission ratio of the wheel belt device and the gearbox can be added, so that the mini tiller can obtain four, six or more gear combinations through such additions.

[0050] Firstly, the gearbox transmission ratio is not limited to a single-gear structure; it can also employ two or three transmission ratios. Combined with a tensioner belt drive mechanism with two different transmission ratios, this allows the mini-tiller to achieve a multi-gear structure with multiple transmission ratios, providing greater variability in its output. Taking a two-ratio gearbox as an example, it can form a six-gear structure, with more targeted applications: ① Two reverse gears: suitable for use when the mini-tiller needs to reverse, outputting different torques to match soft or hard surfaces. ② One forward gear: slow speed, suitable for cultivating soils with high compaction, such as loam (compact) and clay, which are difficult to cultivate. It is also suitable for trenching and ridging in such soils. ③ Two forward gears: relatively slow speed, suitable for cultivating soils with moderate compaction, such as loam (relatively compact) and light clay, which are also suitable for trenching and ridging in such soils. ④ Fast forward first gear: This speed is moderate and suitable for soils with low compaction, such as sandy loam and other easily tilled soils. It is also suitable for subsequent tillage operations on various soil types, as well as trenching and hilling on such soils. ⑤ Fast forward second gear: This speed is faster and suitable for rapid tillage on various soil types. By changing the attachment blades, it can also achieve functions such as rapid weeding and mulching.

[0051] Secondly, the two-belt drive structure used in the aforementioned wheel belt device is a basic structure. Based on this, the belts loosely fitted between the driving and driven pulleys can be increased to three or four, depending on the size, model, specifications, or requirements of the tiller. This allows the wheel belt device to have more transmission ratios. Correspondingly, the same number of tensioning devices, a reasonably designed interlocking control scheme, and the positional relationship of the clutch levers on the handlebars can be implemented. Figure 1 and 6 As shown, by installing one or two clutch handles on a single handrail, the handrail can have three or four clutch handles to match the three- or four-speed ratio structure of the pulley system. Alternatively, a motor with dual output shafts and a reducer with dual input shafts can be installed to match two different sets of pulley systems with different speed ratios, thus obtaining a four-speed-ratio adjustable structure. All of these approaches should have corresponding inspirational effects.

[0052] Example 2

[0053] like Figure 1-4As shown, this embodiment differs from Embodiment 1 in that the tensioning pulley belt drive mechanism further includes an interlocking device 3 for interlocking control of the two tensioning devices 2. The interlocking device 3 consists of a bracket 31, a pull rope 32, a pulley 33, and a pin 34. The pulley 33 rotates on the bracket 31 via the pin 34, while the bracket 31 is fixedly mounted on the wheel frame 8. The pull rope 32 is wound around the pulley 33, and both ends of the pull rope 32 are connected to the rocker arms 21 of the two tensioning devices 2, respectively. Thus, the bracket 31 is fixedly mounted on the mudguard of the wheel frame 8, and a pin 34 is installed at its lower end. The pulley 33 is rotatably mounted inside the bracket 31 on the pin 34. The pull rope 32 is mounted on the pulley 33, and fixed terminals are installed at both ends of the pull rope 32. These two fixed terminals are respectively fixedly installed at the ends of the two rocker arms near the tensioning pulley. When one of the two tensioning devices 2 is pulled, it will simultaneously pull the pull rope 32. That is, after one end of the pull rope 32 follows the upward movement of one tensioning device 2, the other end of the pull rope 32 will pull the other tensioning device downward, thus ensuring that only one belt in the belt device 1 is tensioned, thereby avoiding misoperation or invalid operation caused by the operator simultaneously squeezing the two clutch handles.

[0054] For example Figure 7 As shown, the interlocking device 3 in this embodiment also includes a housing 35, which is covered by the bracket 31 and the pulley 33 and is fixedly installed on the wheel frame 8, which also serves the purpose of safety protection.

[0055] By adopting the above scheme, this mini-tiller uses the interlocking device to control the independent belt drive of the two sets of belt devices with different transmission ratios through the individual operation of the two tensioning devices. It will not cause problems such as interference or no transmission effect in the synchronous transmission of the two sets of belt devices with different transmission ratios due to misoperation or ineffective operation such as simultaneously pressing the two clutch levers.

[0056] Example 3

[0057] like Figure 6 As shown, the difference between this embodiment and embodiment two is that the clutch handles 42 of the two clutch devices 4 are arranged vertically relative to the handles of the handrail 5. In this way, the operator cannot hold both clutch handles and handrail handles at the same time, but can only hold one of the clutch handles and handrail handles with one hand. Thus, without setting the interlocking device 3, the synchronous misoperation of the two clutch devices 4 can be avoided.

[0058] The present invention also proposes a control method based on the multi-speed belt drive micro-tiller, that is, using two clutch devices 4 to control two tensioning devices 2 to act independently on the belt device 1, and the individual actions of the two tensioning devices 2 are interlocked by the interlocking device 3 to quickly switch the belt device 1 with two sets of different transmission ratios, so that the power of the internal combustion engine 7 is transmitted to the gearbox 6 through the belt device 1 to obtain an adjustable multi-speed belt drive output.

[0059] In the initial state, both tension wheels 29 rest on the mudguards of the wheeled vehicle frame 8. The operator selectively presses the clutch handle 42 of one of the clutch devices 4. The clutch handle 42 rotates relative to the pull rope box along the pin, and one end of the extension cable 41 of the clutch device 4 moves relative to it as the clutch handle 42 moves. The other end of the extension cable 41 is connected to the tension spring 28 through the control line 27 and also moves upward, thereby pulling the tension spring 28 upward. The rocker arm 21 connected to the tension spring 28 also rotates upward with the rotating shaft 24. The tension wheel 29, which is rotatably connected to the rocker arm 21, moves toward a corresponding belt (such as the first belt 14), approaches and tightens the corresponding belt (such as the first belt 14), so that the belt can press on the working pulley with appropriate pressure, and the belt drive mechanism starts power transmission. Releasing the clutch handle 42 stops power transmission. Simultaneously, when one of the clutch levers 42 is pressed, the rocker arm 21 of the corresponding tensioning device 2 rotates upward, and the pull rope 32 surrounding the pulley 33 of the interlocking device 3 also rotates with the pulley 33 and is pulled upward. Since the length of the pull rope 32 is fixed, the other end of the pull rope 32 remains at a fixed length and cannot be pulled upward. This ensures that if the operator accidentally touches another clutch lever 42 after pressing one clutch lever 42, the tensioning wheel 29 of the other tensioning device 2 cannot move upward and press its corresponding belt (such as the second belt 15), thus avoiding the phenomenon of two sets of pulleys with different transmission ratios transmitting power simultaneously and reducing operational risks. If different clutch levers 42 are pressed, pulleys with different transmission ratios can be selected to operate, achieving the effect of rapid speed switching.

[0060] In summary, this mini-tiller can select different speed transmission outputs by tightening two sets of belts with different transmission ratios. By installing interlocking devices on the two tensioning devices, it can prevent the two sets of belts with different transmission ratios from transmitting power simultaneously, reducing operational risks. It has the advantages of simple and feasible structure, quick and convenient operation, and safe and reliable operation, and is highly practical, while achieving adjustable multi-speed belt drive output.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A multi-speed ratio belt drive mini-tiller, comprising an internal combustion engine (7), a gearbox (6) and a handrail frame (5) arranged on a wheeled frame (8), the internal combustion engine being in driving connection with the gearbox through a tensioning wheel belt drive mechanism, the tensioning wheel belt drive mechanism comprising: The belt drive device (1) is composed of a driving wheel (11), a driven wheel (12), a first belt (14) and a second belt (15); two tensioning devices (2) are arranged to act on the first belt and the second belt respectively; the driving wheel is arranged on the output shaft of an internal combustion engine, and the driven wheel is arranged on the input shaft of a gearbox; characterized in that the first belt and the second belt are loosely fitted between the driving wheel and the driven wheel in parallel, and the driving wheel and the driven wheel are arranged to have two groups of different transmission ratios corresponding to each other. Each tensioning device is composed of a rocker arm (21), a rotating cylinder (22), a control line (27), a tension spring (28) and a tension wheel (29); one end of the rocker arm is provided with the rotating cylinder, and the other end is provided with the tension wheel for acting on the first belt or the second belt; one end of the tension spring is connected to the rocker arm, and the other end is connected to the control line. The belt drive device further comprises a interlocking device (3) for interlocking the two tensioning devices, which is composed of a pull rope (32) and a pulley (33); the pulley is arranged on a wheel frame and rotates; the pull rope is wound around the pulley, and two ends of the pull rope are connected to the rocker arms of the two tensioning devices respectively. The rotating cylinders arranged on the rocker arms of the two tensioning devices are connected in series to the same rotating shaft (24); a spacing tube (23) is arranged on the rotating shaft between the two rotating cylinders; the rotating shaft is arranged on the gearbox or the wheel frame; the control lines of the two tensioning devices are arranged on the same clutch line seat (25) through a connecting pin (26) at the end away from the tension spring respectively; the clutch line seat is arranged on the wheel frame. The belt drive device further comprises two clutch devices (4) for controlling the control lines of the two tensioning devices respectively; each clutch device is composed of an extension cable (41) and a clutch handle (42); one end of the extension cable is connected to the control line, and the other end is connected to the clutch handle arranged on the handrail frame. The interlocking device further comprises a bracket (31), a pin shaft (34) and a housing (35); the pulley rotates on the bracket through the pin shaft; the housing is arranged on the bracket and the pulley, and is fixed on the wheel frame together with the bracket.

2. The multi-speed ratio belt drive mini-tiller of claim 1, wherein, The belt drive device further comprises a first pressing block (13) arranged on the wheel frame and close to the driven wheel for pressing the first belt, a second pressing block (16) arranged on the wheel frame and close to the driving wheel for pressing the second belt, and a belt cover (17) arranged on the wheel frame for covering the driving wheel and the driven wheel.

3. The multi-speed ratio belt drive mini-tiller of claim 1, wherein, The gearbox is of a herringbone structure, which is composed of a main gear box (61), a front axle gear box (62), a rear axle and tool axle gear box (63); the driven wheel is arranged on the input shaft of the main gear box; the output shaft of the main gear box is connected to the front axle gear box, the rear axle and tool axle gear box respectively; and the transmission ratio of the front axle gear box is smaller than that of the rear axle and tool axle gear box.

4. A control method of a multi-speed ratio belt drive mini-tiller, characterized by, The control method of the multi-speed ratio belt drive mini-tiller according to any one of claims 1-3 comprises: using two clutch devices to control two tension devices to act on the wheel belt device respectively, and the independent actions of the two tension devices are controlled by interlocking devices, so as to quickly switch the wheel belt device with two groups of different transmission ratios, and after the power of the internal combustion engine is transmitted to the gearbox through the wheel belt device, the adjustable multi-speed ratio belt drive output is obtained.

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