NL2032271B1

NL2032271B1 - Automatically adjustable variable speed drive system

Info

Publication number: NL2032271B1
Application number: NL2032271A
Authority: NL
Inventors: Yan Jing; Lu Binglin
Original assignee: Shanghai Chuanlin Prec Parts Co Ltd
Priority date: 2022-06-24
Filing date: 2022-06-24
Publication date: 2024-01-08

Abstract

A new type of N-speed automatically adjustable variable speed drive systems is proposed. The power input shaft of the reducer is divided into N- 1 segments, and N drive gears are mounted on the power shaft by bearings; a single or multiple sets of N consecutive-tooth driven gears are engaged with the above N drive gears; N-1 sliding clutches are integrated with N-1 speed triggers respectively and slide between the drive gears or between the drive gears and the clutch teeth fixed on the segmented power shaft to complete gear shifting. The system allows for easy incorporation of a wide range of different gearboxes.

Description

P132302NL00

Title: Automatically adjustable variable speed drive system

Technology Field

Automatically adjustable variable speed drive systems

Technology Background

Adjustable variable speed systems, is a key technology for vehicle energy efficiency. The ideal CVT system, when implemented, is hardly ideal.

Existing CVT technologies are inherently energy intensive and have high equipment costs. Existing discrete variable speed systems are complex in structure and it takes up space, or requires manual assistance, limiting its application. For low-speed electric vehicles, adjustable variable speed may not be required. However, for vehicles with a wide range of speeds, such as high-speed and medium-speed electric motorcycles, the lack of variable speed functionality will result in waste of energy.

Variable speed system using planetary gear is a classic subject for vehicle shifting. Whereas motorcycle CVT systems use belt drives, Pulley is widely used. Are there other possible applications for planetary gear systems and

Pulley? The basic idea of the present invention starts from thinking about this question. It proposes and realizes an automatically adjustable multi- shift system with simple structure, small space occupation, low cost and reliable operation.

Invention content

The present invention is defined by the claims. The invention provides a new type of automatically adjustable variable speed systems

The automatically adjustable variable speed drive system of the present invention comprises an engine chamber with an electric motor or other engine, a speed reducer chamber with a variable speed reducer, and a power output shaft passing through end cap of said reducer chamber to the outside of the system.

The said variable speed reducer comprises: an input power shaft or input power shaft segment extending from said engine chamber to the reducer chamber through bearings installed on the wall between the engine chamber and the reducer chamber.

N drive gears each with a single side clutch teeth surface are mounted on the input power shaft or input power shaft segment via the bearings in the order of the number of gear teeth from high to lower in the direction from said engine chamber to end cover of said reducer chamber.

N-1 sliding clutches with integrated speed triggers are mounted on the input power shaft or input power shaft segments by means of sliding keys.

N-1 double lateral slipping clutches with integrated speed triggers are mounted on the input power shaft or input power shaft segments by means of sliding keys.

M driven shafts, which are parallel to said power shaft, each with N multi-linked driven gears meshing around the power shaft and said drive gears.

When M=1, the single driven shaft is the said power output shaft, extending outside through the reducer chamber wall; when M is greater than 1, the multi-linked gear shafts are mounted on a rotatable frame via bearings to form a multi-linked planetary gear train, and then engaged with N inner ring gears.

When the planetary carrier is fixed, the power output is the inner ring carrier that integrated with all inner ring gear.

When the inner ring gear holder is fixed, the output

1s the planetary gear holder.

Practical applications for the above systems could include high-speed and medium-speed motorcycles, electric bicycles, electric cars and trucks.

When larger maximum reduction ratio is required, the Group M driven gears will have their own fixed rotating shafts and an additional gear is installed at the end of each shaft.

Those M additional gears are then engaged with an inner ring gear, to form a two-stage N variable speed reducer. The power output in this case is an inner ring gear carrier connected to the said output shaft. This system could be applied to low and medium speed drive hub motors. For applications requiring much higher reduction ratios, such as electric motors for robots, each of the above sets of multiple driven gear shafts can be extended to the cycloid reducer to form an adjustable multivariable speed cycloid reducer.

The power shaft is preferably divided into N-1 segments when the gear shift

N is greater than 2. The power shaft segments are of hollow tubular construction and are attached to a support shaft by bearings and no axial movement is allowed. The first segment is an extension of the rotor power shaft with a drive gear mounted on the edge of the side near the power chamber, followed by a slipping clutch. The second segment of the input power shaft, if it is not the last segment, has a fixed annular clutch teeth surface mounted on the edge near said first segment, followed by a second drive gear, and a slipping clutch. Thereafter it is repeated in all segments in this manner until the last segment, where we have: a fixed annular clutch teeth face, a drive gear, a slipping clutch and the last drive gear. All slipping clutches have double side teeth surfaces. Each driving gear or fixed teeth surface around a slide clutch has teeth surface facing each other. The N drive gears in the different segments have different numbers of gear teeth in the order from large to small. When N = 3, the input power shaft is composed of the first segment and the last segment. When N = 2, the input power shaft is a single unit without central support shaft. In this case, there 1s only a slipping clutch between the two drive gears and the lateral clutch teeth surfaces of the drive gears facing each other.

Preferably, the speed trigger is a special Pulley device with two pre-set trigger speeds. The said speed trigger comprises: a fixed plate mounted on the input power shaft or input power shaft segment, which rotates with said input power shaft or input power shaft segment, but does not allow axial movement. A moving plate mounted on said input power shaft or input power shaft segment, which rotates with the shaft and it could also slide on the shaft. There are a few pairs of Pulley beads between the fixed plate and the moving plate. There is spring acting with the moving plate, pressing the moving plate, the Pulley beads and the fixed plate together. The said slipping clutch is coupled to the moving plate of the speed trigger. There can be paired surface bodies on both the moving plate and the fixed plate which are axisymmetric for the paired Pulley beads to move on the surface. Each

Pulley bead has its own contact body. There are fins on both sides perpendicular to the contact body of the moving plate or the fixed plate to form slotted channels to restrain the Pulley beads. There are inner and outer edge baffles on the fixed plate or moving plate to restrict the movement of Pulley beads in radial direction. The said Pulley beads of the same speed trigger are the same in mass and dimensions. The said contact bodies for a said speed trigger have the same structure and dimensions.

It is preferred that each speed trigger preferably has two trigger rotation speeds, which are called the first trigger speed and the second trigger speed.

When the trigger rotation speed is lower than the first trigger speed, while all Pulley beads are in contact with the inner edge baffle, it is the first state of Pulley beads. Once the rotation speed of the trigger exceeds the first trigger speed, the Pulley beads quickly leave the first state and accelerate into the second state, which is the state where the Pulley beads are in contact with the outer edge baffle. When the rotation speed of the trigger is not lower than the second trigger speed, the Pulley bead and the outer edge baffle are in contact. Once the rotation speed of the trigger 1s lower than the second trigger speed, the Pulley beads move and accelerates to the first state. The first trigger speed is larger than the second trigger speed.

Preferably, when the Pulley bead is in the first state, the moving plate and the fixed plate are closest to each other, and the sliding clutch engages the adjacent clutch teeth on one side of the end cover and completely separates from the adjacent clutch on the other side. When the Pulley bead is in the 5 second state, the moving plate and the fixed plate are farthest apart, and the sliding clutch engages the adjacent clutch teeth on one side of the engine compartment and completely separates from the adjacent clutch teeth on the other side.

The contact surface on said fixing plate is preferably set to be a plane perpendicular to the power shaft. The contact surface on said moving plate is a smooth surface inclined to the fixed plate. The said smooth surface starts from a plane with an angle of intersection 8; with the vertical plane of the power shaft and extends to become a segment of an outer surface of a cylinder with radius greater than the radius of the cylinder of Pulley bead immediately after the contact line between the said plane and the cylindrical Pulley bead when the bead is in the first state. The large cylinder and the cylindrical Pulley bead in the first state are tangential, and the angle at the center of the vertical section of the large cylinder corresponding to this segment of the cylinder face is 91-02 where 62 is the intersection angle between tangential plane at of the end of the segment of the large cylindrical outer surface and the vertical plane of the power axis. In general, we have: 6; >0¢ for making sure that the second trigger speed is lower than the first trigger speed to enhance the stability of the system during gear shifting. We also set that when the Pulley bead is in contact with the end of the smooth surface, the Pulley bead rests exactly on the said outer edge baffle. To be sure that the trigger has the characteristics in (a) above, we set the initial compressed length AX of the compression spring, and the distance ro, satisfy the relationship AX > ro tan 6;, where ro is the distance between the centerline of the Pulley bead in the first state and the centerline of the input power shaft.

Specific Embodiments

The description herein relates only to preferred embodiments of the present invention.

Illustration

Figure 1A shows an example of a three-speed implementation;

Figure 1B shows detail QB of Figure 1A;

Figure 1C shows detail QC of Figure 1A;

Figure 2A shows an example of a simplified two-speed gearing scheme;

Figure 2B shows detail R of Figure 2A; and

Figure 3 shows a sketch of the variable speed structure.

As in Figure 1 (i.e. Figures 1A, 1B, 1C), we illustrate the structure and action of the drive system of the present invention using an example of the electric motor system with three variable speeds. Without losing generality, we assume the inner rotor 1 of the motor is at left side of the drive train.

The rotor shaft, i.e. the power shaft 2, is of tubular construction. The outer bearing 3 of the power shaft is mounted in a bearing sleeve on the reducer fixing plate 4. The center support shaft 5 and the rotor shaft are connected with bearing 6. The other end of the central support shaft is mounted on the right end cover of the integrated motor system. Sun wheels 7, 8, 9 are placed along the shaft from left to right in order of diameter from largest to smallest and are attached to the power shaft with bearings respectively.

Sun wheels 7, 8 have a clutch teeth surface on the right side and sun wheel 9 has a clutch teeth surface on the left side. The first segment of the power shaft is on the left side. The sun wheel 7 is located on the leftmost side of the first segment. There is a slide clutch with double-sided teeth surface 10 integrated with trigger 11 on the right side. 12 is the fixed plate. The slide clutch is installed to the power shaft with sliding keys. The clearance between the second segment and the first segment of the power shaft is fairly small. The second segment 13 is fixed on the central support shaft 5 with bearings, and no axial movement is allowed. The left side of the second power shaft segment is equipped with a fixed clutch teeth surface. It allows the slide clutch teeth 10 to engage with the fixed plate when it moves toward it. 14 is a spring. The rest of the second segment are, in order, the second sun wheel 8, the spring 15, the second moving clutch teeth surface 16 and the speed trigger 17, the fixed plate 18, and the third sun wheel 9.

When power train is at rest, all slide clutch teeth surfaces move to the up- right position under spring force. The first slide teeth surface is disengaged from the leftmost sun wheel and engages with the fixed teeth surface of the second segmented power shaft. On the other hand, the second slide teeth surface is disengaged from the second sun wheel 8 under spring force and engages the third sun wheel 9 at the right. The system is ready to start. The power is transferred to the smallest sun gear, which in turn is transferred to the planetary gear 19, which in turn is output through ring gear 21 while planetary carrier 20 is fixed. For simplicity, the planetary gear train uses multiple connecting gears. At the time of starting, the maximum speed reduction ratio is functioning and the vehicle starts to move. When the vehicle speed increases and the power shaft turning speed increases beyond the first trigger speed speed of the second speed trigger, the second clutch moves to the left, disengaging the sun wheel 9 and engaging the sun wheel 8, and the system completes the gear changes. The power is transmitted from the sun wheel 8 to the planetary wheel set 22, and then output by ring gear 23. When the power continues to increase and the turning speed of the power shaft increased beyond the first trigger speed of the first speed trigger, the first speed trigger acts, pushing slide clutch traveling to the left and disengages the fixed teeth surface of the segmented shaft, causing the second segment to lose power and the second sun wheel become inactive.

The first slip clutch continues to travel to the left and engages with the first sun wheel to complete the gear changes. The power is transferred from the largest sun gear 7 to the planetary gear set 24, which is then output by ring gear 25.

When vehicle speed decreases, the power shaft speed decreases. The left slide clutch is disengaged from the first sun gear 7 and engages with the fixed tooth surface of the second segmented power shaft. The second segmented power shaft gains power, causing the right side clutch surface to travel left, gearing the sun gear 8 and completing the shift. As power continues to decrease, the second clutch surface travels right, disengaging the second sun gear 8 and engaging with the first sun gear 9, the system is operating on first gear. The speed continues to decrease until it comes to a complete stop on first gear. The system returns to its previous wait and run state.

The motor reaches its peak efficiency when it reaches its rated speed. After the maximum efficiency is reached, the motor still has certain speed range before reaching its maximum speed. Above and below the optimal efficiency speed, N-1 speed triggers with different first trigger speed and second trigger speed can be arranged to build an N-speed automatic speed reduction system that operates in sequence without interfering with each other.

Figure 2 (i.e. Figures 2A, 2B) illustrate one of the simplest examples of variable speed system of the present invention. The electric motor compartment is on the left, with a stator 27, a rotor 28 and a rotor shaft 29.

On the right of the system is a two-speed reduction gearbox. The power is transmitted to the input power shaft 30 of the gearbox. Drive gears 31, 32 are fixed to the input power shaft by bearings 33, 34. The speed trigger 37 is between gears 31 and 32 and is connected to the input shaft 30 with a fixed plate and a moving plate. Part 35 is a retaining plate, part 36 is a Pulley bead, and part 37 is a compression spring. Part 26 1s a double-linked gear shaft. Power is input through input power shaft 30 and speed trigger 38 rotates with the input power shaft. When turning speed of the trigger is below the first trigger speed, the spring force pushes the contact surface, pressing the Pulley beads against the inner baffle, and the low gears 31 and 39 begin to operate. When the power system accelerates and exceeds the first trigger speed of the speed trigger, the centrifugal force drives the

Pulley beads up and pushes the sliding gear surface to the left. At this point the Pulley beads will be accelerated to reach the outer baffle of the trigger, making gears 32 and 40 working. The system completes the shift from low to high gears. When the power system decelerates and the rotation speed of the input power shaft segment is less than the second trigger speed of the speed trigger, the movable smooth surface presses the Pulley bead back to the inner baffle, the sliding clutch surface and the clutch surface of gear 32 are completely disengaged, and gear 32 and gear 40 do not transmit power. At this point, the sliding clutch teeth surface and the side clutch teeth surface of gear 31 engages, gears 31 and 39 begin to operate, and the system 1s back to low gear.

Figure 3 gives a sketch of the speed trigger and the associated Pulley beads, contact surfaces, and axial moveable distance. In this figure, 41 is a cross- section of the input power shaft wall. 42 is the fixed plate of the trigger, and the outer and inner edge baffles are combined with the fixed plate. 43 is the

Pulley bead. 44 is the moving plate contact body surface. The solid lines represent the position of the Pulley bead in the first state. The dashed line marks the positions of the Pulley bead and the contact body when the bead is in the second state. AX is the maximum axial travel distance of the moving plate during the trigger operation. 97-82 and the corresponding large arc segment indicate how the curved contact surface should be formed.

Description of the symbols in the figure 1.motor 2. input power shaft 3. bearing 4. reducer fixing plate 5. center support shaft 6. bearing 7. sun wheel I 8. sun wheel II 9. sun wheel III 10. speed trigger 11. Pulley bead 12 fixing plate 13. second segment shaft 14. spring 15. spring 16. speed trigger II 17. Pulley bead 18. cover 19. planetary wheel set I 20. planetary frame 21. Gear ring I 22 Planet wheel set Il 23.gear ring II 24 planet wheel set ITI 25. gear ring III 26.duplex gear shaft 27 stator 28.rotor 29.rotor shaft 30.input power shaft 31.drive gear I 32.drive gear II 33.bearing 34.bearing 35.fixed plate 36. Pulley bead 37.spring 38.speed trigger III 39.driven gear I 40.driven gear II 41.1nput power shaft 42 fixed plate 43. Pulley bead 44.speed trigger

References (1) Patent Name: Pulley, Patent inventor: Warren H. Delancey, Patent

Application Number: US05877018, Date of Application: 19780213

Claims

Conclusions

1. An automatically adjustable variable speed propulsion system, comprising: -an engine compartment with an electric motor or other motor; -a speed reduction compartment containing an automatically adjustable variable speed reducer; -a power output shaft passing through the end cap of said reduction compartment to the outer part of the system; wherein said variable speed reducer comprises: -an integral input power shaft or a multi-segmented input power shaft; -for N gears, N drive gears each having a side clutch teeth surface mounted on the input power shaft or input power shaft segments via bearings according to the order of the number of gear teeth from high to low along the direction from said engine compartment to said reducer compartment; -N-1 double lateral slip clutches with integral speed triggers mounted on the input power shaft or input power shaft segments by means of sliding keys; -M driven shafts, running parallel to said power shaft, each with N multi-coupled driven gears meshing around the power shaft and said drive gears; -when M=1, the single driven shaft is the said power output extending externally through the wall of the reduction compartment; -when M is greater than 1, the multi-coupled gear shaft may be mounted on a rotatable frame via bearings to form a multi-coupled planetary gear set and then N inner ring gears connected to a frame meshing with M multi-coupled planetary gears; -when the planetary gear frame fixed for 1s, the power output is the inner ring gear frame; -when the inner ring gear frame is fixed, the power output is the planetary gear frame; -where the M sets of multi-coupled driven gears have their own independent fixed axes of rotation, a pinion is mounted on the end of each shaft, and the M additional pinions are meshed with an inner ring gear, forming a two-step N gear adjustable variable speed reducer ; -power output in this case is the inner ring gear connected to said power output shaft.

An automatically adjustable variable speed drive system according to claim 1, characterized in that: when the number of gears N is greater than 2, said input power shaft comprises N-1 segments; all input power shaft segments are of hollow tube construction, connected by bearings to a central support shaft; and the input power shaft segments are axially fixed; the first segment is an extension of the power shaft from said engine compartment; the first drive gear is mounted on the first segment next to the engine compartment, followed by a slipper clutch; the second segment of the input power shaft, if not the last segment, has a fixed annular clutch teeth surface mounted on its edge adjacent said first segment, followed by a second drive gear, and a slipper clutch; then it is repeated in this way in all segments until the last segment, where we have: a fixed annular clutch teeth surface, a driving gear, a slipping clutch and the last driving gear; wherein each drive gear or fixed tooth surface around a sliding coupling has a tooth surface facing each other; when N=3, the input power axis has only the first segment and the last segment; when N=2, the input power shaft is a single unit without a central support shaft; in this case, there is only a slip clutch between the two driven gears and the lateral clutch tooth surfaces of the driven gears facing each other.

An automatically adjustable variable speed drive system according to claim 1, characterized in that: said speed trigger is a special Pulley (ref. 1) device with two trigger speeds; wherein the speed trigger comprises: - a fixed plate mounted on said input power shaft or input power shaft segment, which rotates with said input power shaft or input power shaft segment, but fixed in the axial direction 1s; -a moving plate mounted on said input power shaft or input power shaft segment, which rotates with the input power shaft or input power shaft segment, but can also slide on the shaft; -a number of pairs of pulley rollers between the fixed plate and moving plate; -a spring that acts with the moving plate, compressing the moving plate, the pulley rollers and the fixed plate; - said slip clutch is coupled to the moving plate of the speed trigger;

- on both the moving plate and the fixed plate there are pairs of contact bodies, which are axially symmetrical for the pulley rollers to move on the surfaces of said contact bodies; -each pulley roller has its own contact body around said moving and fixed plates;

-each pulley roller is confined by a channel formed by the flanking fins perpendicular to the contact bodies of the moving or fixed plates; -the said moving or fixed plates have inner and outer edge baffles to limit the radial movement of the pulley rollers; -the said pulley rollers of a said speed trigger are the same in mass and dimensions; said contact bodies of said speed trigger have the same structure and dimensions; - wherein said speed trigger and the fixed plate, moving plate contact body are further characterized in that: (a) each speed trigger has two preset trigger rotation speeds, which are called the first trigger speed and the second trigger speed, respectively; when the Pulley rollers are in contact with the inner edge bulkhead and are stationary, the Pulley rollers are in the first state; once the speed of the trigger exceeds the first trigger speed, the pulley rollers quickly break out of the first state and accelerate into the second state, which is the state where the pulley rollers are in contact with the outer edge baffle; when the rotation speed of the trigger is not lower 1s than the second trigger speed, the Pulley rollers remain in the second state and are stationary; once the rotation speed of the trigger is lower 1s than the second trigger speed, the Pulley rollers will leave the second state and accelerate to the first state; said first trigger speed is greater than said second trigger speed. (b) the two states of the Pulley rollers correspond to two positions of the sliding clutch; when the pulley rollers are in the first state, the moving plate and the fixed plate are at the nearest positions, and the sliding clutch engages the adjacent clutch teeth on the end cap side, while it is completely separated from adjacent clutch teeth on the other by 1s silk; when the Pulley rollers are in the second state, the moving plate and the fixed plate are furthest apart, and the sliding clutch engages with the adjacent teeth on the engine compartment side, while it is completely separated with adjacent clutch on end cap side; (c) where (see Figure 3) the surface of said contact body on the fixed plate can be arranged to be a plane perpendicular to the power axis, the surface of said contact body on the moving plate 1s a smooth surface inclined to the fixed plate; said smooth surface starts from a plane with an angle of intersection 0; with the vertical plane of the power axis and extends to form a segment of an outer surface of a cylinder of radius greater than the radius of the cylinder of Pulley roller immediately after the line of contact between said plane and the cylindrical Pulley roller while the roller is in the first state, the large cylinder and the cylindrical Pulley roller in the first state are tangential; and the angle at the center of the vertical part of the large cylinder corresponding to this segment of the cylinder outer surface is 81- 02, where 62 is the angle of intersection between tangential plane at the end of the segment of the large cylindrical outer surface and the vertical plane of the power axis; in general we have 0:>82; we further state that when the Pulley roller is in contact with the end of the smooth surface, the Pulley roller rests exactly on the said outer edge baffle; to ensure that the velocity trigger has the characteristics in (a), we set the initial compressed length AX; of the compression spring, and the distance ro, satisfy the relationship AX > ro tan 01, where ro is the distance between the centerline of the Pulley roller in the first state and the centerline of the Input Power Shaft.

4. An automatically adjustable variable speed drive system according to claim 1, characterized in that the first and second trigger speeds of the N-1 trigger speeds in the N automatically adjustable variable speed drive system decrease sequentially from a high gear to a lower gear around the optimum efficiency speed of the power system; the speed trigger parameters vary for different triggers for different gears.