Flexible transmission device and control method

Abstract

This invention relates to the field of mechanical transmission technology, and more particularly to a flexible gear shifting device and control method. Significant rigid impact and jamming occur during gear shifting, severely affecting shifting quality and device lifespan. This invention, through ingenious mechanism integration design, combines the gear shifting function with power input into one. Power transmission and mode switching can be completed simultaneously with the rotation of a single input handle, eliminating the need for a separate gear shifting actuator, simplifying the system structure, and reducing manufacturing costs. The coordinated operation of an angle amplification mechanism and a precision cam mechanism converts small-angle input into precise, large-stroke axial displacement. This not only achieves smooth clutch disengagement and re-engagement but also ensures smooth motion cycles through cam curve optimization, achieving efficient and reliable gear shifting.

Description

Technical Field

[0001] This invention relates to the field of mechanical transmission technology, and in particular to a flexible speed-changing device and control method. Background Technology

[0002] In existing technologies, flexible speed change mainly uses belt or steel belt drive, which achieves continuous change of transmission ratio by changing the effective diameter of the pulley. Although it can ensure smooth transmission, its transmission efficiency is low and the speed change range is limited.

[0003] Another common transmission method uses a multi-plate clutch or a jaw clutch for gear switching, but there is obvious rigid impact and jamming during the switching process, which seriously affects the shifting quality and the life of the device. Summary of the Invention

[0004] In view of the shortcomings of existing technologies, this invention proposes an innovative flexible speed change device and control method, which is applicable to mechanical speed change equipment and achieves the purpose of flexible switching of transmission ratios twice within a limited angle range.

[0005] This invention proposes a flexible speed change device, which includes an input shaft, a splined shaft, and a splined gear shaft arranged parallel to each other on a frame. A manual switching mechanism is fixedly mounted on the input shaft, and a high-speed input gear and a low-speed input gear are rotatably mounted on it. A clutch mechanism and an output gear are mounted on the splined shaft. The cam actuation mechanism includes a cam disk fixedly mounted on the splined gear shaft and a connecting rod slidably mounted on the frame. A shift fork and a cam follower are fixedly mounted on the connecting rod. The lower end of the cam follower is inserted into a Z-shaped groove of the cam disk. The shift fork is connected to the clutch mechanism. The rotation of the cam disk is controlled by the manual switching mechanism, and the clutch mechanism is moved by the shift fork based on the groove shape, thereby switching the transmission relationship with the high-speed input gear and the low-speed input gear.

[0006] Advantageously, the manual switching mechanism includes a fixed sleeve and a switching gear fixedly mounted on the input shaft, and the switching handle is integrated with the fixed sleeve.

[0007] Advantageously, the tooth ends of the splined gear shaft mesh with the switching gear.

[0008] Advantageously, the clutch mechanism is a disc-shaped structure, including a switching disc connected to the shift fork. On one side of the switching disc are a synchronously rotating high-speed clutch disc and a high-speed gear, which meshes with the high-speed input gear. The high-speed clutch disc has teeth facing the switching disc. On the other side of the switching disc are a synchronously rotating low-speed clutch disc and a low-speed gear, which meshes with the low-speed input gear. The low-speed clutch disc has teeth facing the switching disc.

[0009] Advantageously, there are multiple sets of flexible buffer mechanisms between the high-speed clutch disc and the high-speed gear, and between the low-speed clutch disc and the low-speed gear. Each set includes a pin fixedly mounted on both clutch discs. The pin passes through the gear and the cover plate and is fixed. A spring is mounted on the pin to maintain a gap between the clutch and the corresponding gear.

[0010] Advantageously, the switching disc includes a bushing, an intermediate disc, and a geared disc. The bushing is connected to a splined shaft key, the intermediate disc is fixedly connected to the shift fork, and there are geared discs on both sides of the intermediate disc, with the two geared discs fixedly connected to the bushing.

[0011] Advantageously, a reversing gear that meshes with the output gear is also mounted on the frame.

[0012] Advantageously, the frame is divided into three areas by four parallel partitions, with a splined gear shaft mounted on the first partition and an input shaft and a splined shaft mounted on the second and third partitions.

[0013] Advantageously, the middle section of the input shaft is fitted with a high-speed input gear and a low-speed input gear via bearings; the high-speed gear and the low-speed gear are connected to the splined shaft via bearings.

[0014] The present invention also proposes a control method for the flexible transmission device as described above. When the operator rotates the manual switching mechanism to the switching point of the groove, the cam follower driven by the groove shape drives the connecting rod to move axially, and at the same time drives the clutch mechanism to switch the transmission relationship with the high-speed input gear and the low-speed input gear.

[0015] Beneficial effects: 1. The innovative use of a pre-pressure adjustable switching disc effectively absorbs shifting shock through a flexible buffer device, solving the problems of jamming and rigid impact that are prone to occur during left and right switching of traditional clutches, and significantly improving shifting smoothness and device service life.

[0016] 2. Through ingenious mechanism integration design, the shifting function and power input are combined into one. Power transmission and mode switching can be completed simultaneously by rotating a single input lever, eliminating the need for a separate shifting actuator, simplifying the system structure and reducing manufacturing costs.

[0017] 3. By employing the coordinated operation of an angle amplification mechanism and a precision cam mechanism, a small angle input is converted into a precise large-stroke axial displacement. This not only enables smooth disengagement and re-engagement of the clutch, but also ensures the smoothness of the motion cycle through optimization of the cam curve, achieving a highly efficient and reliable speed switching function. Attached Figure Description

[0018] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly explained below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The reference numerals are as follows: Figure 1 This is a schematic diagram of the overall structure of the flexible speed change device of the present invention; Figure 2 This is a top sectional view of the flexible speed change device of the present invention; Figure 3 This is a schematic diagram of the manual switching mechanism; Figure 4 This is a schematic diagram of a cam actuation mechanism; Figure 5 This is a schematic diagram of the clutch mechanism; Figure 6 This is a schematic diagram of the switching disk structure; Figure 7 This is a schematic diagram of the flexible buffer mechanism between the low-speed clutch disc and the low-speed gear.

[0019] 1-Manual switching mechanism, 101-Switching handle, 102-Fixed sleeve, 103-Switching gear, 14-Splined gear shaft, 2-Cam actuation mechanism, 201-Cam disc, 202-Shift fork, 203-Cam follower, 204-Connecting rod, 3-Clutch mechanism, 301-Switching disc, 301-1-Shaft sleeve, 301-2-Intermediate disc, 301-3-Gear disc, 302-High-speed clutch disc, 303-High-speed gear, 304-Low-speed clutch disc, 305-Low-speed gear, 4-Frame, 5-Output gear, 6-Reversing gear, 7-High-speed input gear, 8-Low-speed input gear, 9-Input shaft, 10-Pin, 11-Cover plate, 12-Spring, 13-Splined shaft Detailed Implementation See Figure 1 and Figure 2 The flexible transmission device shown includes a manual switching mechanism 1, a cam actuation mechanism 2, a clutch mechanism 3, a frame 4, an output gear 5, a reversing gear 6, a high-speed input gear 7, a low-speed input gear 8, an input shaft 9, and a splined shaft 13. In this embodiment, the frame 4 is divided into three areas by four parallel partitions. A splined gear shaft 14 is installed on the first partition, and the input shaft 9 and the output splined shaft 13 are installed on the second and third partitions. The middle section of the input shaft 9 is fitted with a high-speed input gear 7 (module 0.5) and a low-speed input gear 8 (module 0.5) via bearings. The output gear 5 is installed at the outer end of the splined shaft 13, and a reversing gear 6 is also installed on the fourth partition, meshing with the output gear 5.

[0020] See Figure 3The manual switching mechanism 1 shown in the embodiment includes a switching handle 101, a fixed sleeve 102, and a switching gear 103. The fixed sleeve 102 of the manual switching mechanism 1 is fixed to the input shaft 9 via a spline and axially fixed by a snap ring. The switching handle 101 and the fixed sleeve 102 are connected as a single unit; in this embodiment, the switching handle 101 and the fixed sleeve 102 are connected by a thread. A high-speed input gear 7 and a low-speed input gear 8 are distributed on both sides of the fixed sleeve 102, respectively mounted on the input shaft 9 via bearings and axially fixed by snap rings. The switching gear 103 is connected to the input shaft 9 on the left side via a spline and axially fixed by a snap ring. A splined gear shaft 14 is mounted on the first partition via bearings and rotates on the frame 4. The switching gear 103 and the splined gear shaft 14 form a gear pair, achieving angle amplification. In this embodiment, the amplification factor is 6, allowing a small angle rotation of the switching handle 101 to achieve a large angle rotation of the splined gear shaft 14.

[0021] See Figure 4 The cam actuation mechanism 2 shown includes a cam disk 201 with grooves, a shift fork 202, a cam follower 203, and a connecting rod 204. The cam disk 201 is fixedly connected to the spline gear shaft 14 to achieve synchronous rotation. The connecting rod 204 is mounted on the upper side of the first and third partitions and can slide axially. The cam follower 203 and the shift fork 202 are both fixedly connected to the connecting rod 204 and can move synchronously with the movement of the connecting rod 204. The lower side of the shift fork 202 is connected to the intermediate disk 301-2 of the switching disk 301. The working surface of the cam disk 201 is a Z-shaped groove designed on the annular surface according to the transmission angle relationship. The extension of the cam follower 203 is inserted into the groove to cooperate. During the rotation of the cam, the cam follower 203 achieves axial translation according to the shape of the groove. Since the gear of the splined gear shaft 14 and the switching gear 103 form a gear pair, when the switching handle 101 drives the switching gear 103 to rotate by a small angle (e.g., 1°), the splined gear shaft 14 can rotate by a large angle, calculated according to the gear pair transmission ratio. During switching, the control cam follower 203 and the shift fork 202 generate the required displacement during translation, without requiring the switching handle to rotate by a large angle or even multiple turns to complete the switching process, and without any jamming.

[0022] like Figure 5 The clutch mechanism 3 shown is a disc-shaped structure, including a coaxial switching disc 301, a high-speed clutch disc 302, a high-speed gear 303, a low-speed clutch disc 304, a low-speed gear 305, and a splined shaft 13. The switching disc 301 includes a pair of outer annular gear discs and an intermediate bushing. The annular gear discs have a straight tooth structure on the circumferential surface of the disc body, which can engage with the gears.

[0023] High-speed gear 303 and low-speed gear 305 are connected to splined shaft 13 via bearings to form a rotating pair, allowing free rotation on the splined shaft. High-speed gear 303 meshes with high-speed input gear 7, and low-speed gear 305 meshes with low-speed input gear 8. A flexible buffer mechanism exists between high-speed clutch disc 302 and high-speed gear 303, and they rotate synchronously; a flexible buffer mechanism also exists between low-speed clutch disc 304 and low-speed gear 305, and they rotate synchronously. Both high-speed clutch disc 302 and low-speed clutch disc 304 have radially inward-facing teeth on their circumference, which can engage with radially outward-facing teeth on switching disc 301, respectively.

[0024] See Figure 6 The switching disk 301 shown includes a bushing 301-1, an intermediate disk 301-2, and a gear disk 301-3. The intermediate disk 301-2 is fixedly connected to the shift fork 202. There are gear disks 301-3 on both sides of the intermediate disk 301-2. The two gear disks 301-3 are fixedly connected to the bushing 301-1. The bushing 301-1 is keyed to the spline shaft 13.

[0025] See Figure 7 The flexible buffer mechanism between the low-speed clutch disc 304 and the low-speed gear 305 includes an internally nested pin 10, a cover plate 11, and a spring 12. The low-speed gear 305 has bolt holes on its body. The pin is threaded into the bolt holes. The spring 12 is sleeved on the pin. The other end of the pin passes through the low-speed clutch disc 304 and the cover plate 11 and is connected to the pin and nut. The low-speed clutch disc 304 can slide on the pin. The cover plate 11 ensures that the low-speed clutch disc 304 does not come off. The spring 12 maintains a small gap between the low-speed clutch disc 304 and the low-speed gear 305.

[0026] The flexible buffer mechanism can be rationally arranged in number and position according to the diameter of the clutch disc and gear to ensure smooth switching force. In this embodiment, four sets are set. During switching, the switching disc 301 will experience two engagement scenarios. In the first scenario, the clutch teeth do not interfere and insert normally. In the second scenario, the clutch teeth interfere, for example, the switching disc 301 and the low-speed clutch disc 304 experience tooth interference. Under the action of axial force, the low-speed clutch disc 304 compresses the spring and produces a slight displacement in the axial direction to avoid interference and jamming. When the low-speed gear 305 continues to rotate a small angle, the low-speed clutch disc 304 returns to its original axial position under the action of the flexible buffer mechanism, completing engagement with the right-side low-speed gear 305 and realizing the switching of the transmission ratio. The switching process of the switching disc 301 to the left is the same as the switching process to the right.

[0027] Low-speed to high-speed working process and principle: Initial state: Switching disc 301 is engaged with low-speed clutch disc 304.

[0028] Switching process: When it is necessary to switch to the high-speed gear, the operator rotates the switching handle 101 to the starting position of the switching point groove inflection point. During switching, for every 1° rotation of the switching handle 101, the cam disk 201 rotates 6°, and the groove pushes the cam follower 203 to move axially, converting the rotational motion of the cam disk 201 into the axial movement of the switching disk 301 driven by the connecting rod 204.

[0029] After the switching disc 301 disengages from the low-speed clutch disc 304, the switching disc 301 continues to move to the other end, and the toothed end of the gear disc 301-3 contacts the toothed end of the high-speed clutch disc 302. At this time, the flexible switching device starts to work: the axial force generated by the toothed end contact compresses the spring 12, avoiding jamming or impact. As the high-speed clutch disc 302 continues to rotate, the geared end of the switching disc 301 301 inserts into the high-speed clutch disc 302.

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this invention clearer, the invention will be further described below with reference to the accompanying drawings and embodiments. The described embodiments are only a portion of the embodiments of this invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of this invention.

Claims

1. A flexible speed-changing device, characterized in that: The device includes an input shaft (9), a spline shaft (13), and a spline gear shaft (14) arranged parallel to each other on the frame (4). A manual switching mechanism (1) is fixedly mounted on the input shaft (9), and a high-speed input gear (7) and a low-speed input gear (8) are rotatably mounted on the input shaft (9). A clutch mechanism (3) and an output gear (5) are mounted on the spline shaft (13). The cam actuation mechanism (2) includes a cam disk (201) fixedly mounted on the spline gear shaft (14) and a connecting rod (204) slidably mounted on the frame (4). A shift fork (202) and a cam follower (203) are fixedly installed on the connecting rod (204). The lower end of the cam follower (203) is inserted into the Z-shaped groove of the cam disk (201). The shift fork (202) is connected to the clutch mechanism (3). The rotation of the cam disk (201) is controlled by the manual switching mechanism (1). Based on the shape of the groove, the shift fork (202) drives the clutch mechanism (3) to move, thereby switching the transmission relationship with the high-speed input gear (7) and the low-speed input gear (8).

2. The flexible speed change device according to claim 1, characterized in that: The manual switching mechanism (1) includes a fixed sleeve (102) and a switching gear (103) fixedly installed on the input shaft (9), and the switching handle (101) is connected to the fixed sleeve (102) as a whole.

3. The flexible speed change device according to claim 2, characterized in that: The tooth ends of the splined gear shaft (14) mesh with the switching gear (103).

4. The flexible speed change device according to claim 3, characterized in that: The clutch mechanism (3) is a disc-shaped structure, including a switching disc (301) connected to the shift fork (202). On one side of the switching disc (301) are a synchronously rotating high-speed clutch disc (302) and a high-speed gear (303), which meshes with the high-speed input gear (7). The high-speed clutch disc (302) has teeth facing the switching disc (301). On the other side of the switching disc (301) are a synchronously rotating low-speed clutch disc (304) and a low-speed gear (305), which meshes with the low-speed input gear (8). The low-speed clutch disc (304) has teeth facing the switching disc (301).

5. The flexible speed change device according to claim 4, characterized in that: Multiple sets of flexible buffer mechanisms are provided between the high-speed clutch disc (302) and the high-speed gear (303), and between the low-speed clutch disc (304) and the low-speed gear (305). Each set includes a pin (10) fixedly mounted on both clutch discs. The pin (10) passes through the gear and the cover plate (11) and is fixed. A spring (12) is installed on the pin (10) to keep the clutch and the corresponding gear at a gap.

6. The flexible speed change device according to claim 5, characterized in that: The switching disk (301) includes a bushing (301-1), an intermediate disk (301-2), and a gear disk (301-3). The bushing (301-1) is keyed to the spline shaft (13), the intermediate disk (301-2) is fixedly connected to the shift fork (202), and there are gear disks (301-3) on both sides of the intermediate disk (301-2). The two gear disks (301-3) are fixedly connected to the bushing (301-1).

7. The flexible speed change device according to claim 6, characterized in that: A reversing gear (6) that meshes with the output gear (5) is also installed on the frame (4).

8. The flexible speed change device according to claim 7, characterized in that: The frame (4) is divided into three areas by four parallel partitions. A spline gear shaft (14) is installed on the first partition, and an input shaft (9) and a spline shaft (13) are installed on the second and third partitions.

9. The flexible speed change device according to claim 7, characterized in that: The input shaft (9) in the middle area is equipped with a high-speed input gear (7) and a low-speed input gear (8) via bearings; the high-speed gear (303) and the low-speed gear (305) are connected to the spline shaft (13) via bearings.

10. A control method for a flexible transmission device as described in any one of claims 1-9, characterized in that: When the operator rotates the manual switching mechanism (1) to the switching point of the groove, the cam follower (203) is driven by the groove shape to move the connecting rod (204) axially, and at the same time the clutch mechanism (3) is driven to switch the transmission relationship with the high-speed input gear (7) and the low-speed input gear (8).

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