WO2020182163A1

WO2020182163A1 - Bidirectional overrunning clutch and two-speed transmission

Info

Publication number: WO2020182163A1
Application number: PCT/CN2020/078854
Authority: WO
Inventors: 熊建文
Original assignee: 熊建文
Priority date: 2019-03-12
Filing date: 2020-03-11
Publication date: 2020-09-17

Abstract

Disclosed are a bidirectional overrunning clutch and a two-speed transmission. The bidirectional overrunning clutch comprises input teeth (2), fixed teeth (1), a transmission assembly and an output member, wherein the output member is a planetary carrier (4); the transmission assembly comprises several groups of planetary gears (3) provided on the planetary carrier, input ends of the planetary gears are engaged with the input teeth, and other ends thereof are engaged with the fixed teeth; and per unit time, the ratio of the number of teeth passed by a planetary gear engaged with the fixed teeth to the number of the fixed teeth is equal to the ratio of the number of teeth passed by a planetary gear engaged with the input teeth to the number of the input teeth. The two-speed transmission, which comprises the bidirectional overrunning clutch, further comprises a shunting assembly and a brake (009), wherein the shunting assembly comprises an input member (008) and two shunting members (005, 007), one of the shunting members is fixedly connected to the output member of the bidirectional overrunning clutch, the other shunting member is fixedly connected to the input teeth of the bidirectional overrunning clutch, and the brake is used for controlling the input of the bidirectional overrunning clutch; and the input of the shunting assembly is a two-speed transmission input, and the output of the bidirectional overrunning clutch is a two-speed transmission output.

Description

Two-way overrunning clutch and two-speed transmission

Technical field

The invention belongs to the technical field of mechanical transmission, and particularly relates to a two-way overrunning clutch and a two-speed transmission.

Background technique

The two-way overrunning clutch, as a transmission component, is a component used for power transmission and separation between the prime mover and the working machine. It is a device with self-clutching function by using the speed change of the main and the driven part or the change of the rotation direction. The mainstream overrunning clutches transmit torque by friction, and the torque transmitted is limited by multiple factors such as the material and volume of the component. They are generally used in mechatronics products and are not suitable for driving automobiles.

At present, most electric vehicles on the market are driven by a motor plus a single-stage reducer. The advantages of a single-stage reducer are very obvious, with a simple structure, small size and high transmission efficiency. But the shortcomings of the single-stage reducer are also prominent. In the case of high speed, the efficiency and torque of the motor will drop rapidly, and the noise will increase significantly. Long-term high-speed driving will seriously affect the car's endurance; when the car starts, the motor will Output a short-term large torque, which requires very high requirements for the instantaneous peak power of the car battery, the overload capacity of the controller, and the overload capacity of the motor. Therefore, pure electric vehicles need a two-speed transmission to improve the power performance at low speeds and the economy at high speeds. The traditional two-speed transmission mostly removes the clutch on the basis of the manual transmission, and shifts gears by means of motor speed regulation. This kind of gear shifting method has extremely high requirements on the control system, and it may fail to shift gears and cause repeated shifts. The advantages of the two-speed transmission cannot be fully utilized.

Summary of the invention

The purpose of the present invention is to provide a two-way overrunning clutch capable of transmitting large torque and a two-speed transmission with simple and reliable gear shifting and without power interruption during gear shifting, aiming at the deficiencies of the prior art.

The two-way overrunning clutch provided by the present invention includes input teeth, fixed teeth, a transmission assembly and an output member; the output member is a planet carrier; the transmission assembly includes several sets of planetary gears arranged on the output member, the input end and the input gear Meshing, the other end meshes with the fixed teeth; within a unit time, the ratio of the number of teeth rotated by the planetary gear meshed with the fixed teeth to the number of fixed teeth is equal to the ratio of the number of teeth rotated by the planetary gear meshed with the input teeth to the number of input teeth.

In a specific embodiment, the input teeth and the fixed teeth are both half-shaft gears, the number of teeth of both are equal, and the fixed teeth are fixedly connected to the casing; the transmission assembly includes two sets of planetary gears with the same specifications, two sets The planetary gears are arranged side by side and mesh with each other. One set of planetary gears meshes with the input teeth, the other set of planetary gears meshes with the fixed teeth, and the gear shafts of the two sets of planetary gears are fixedly connected with the planet carrier.

As an alternative, the fixed tooth is a ring gear fixed in the casing; the input tooth is a sun gear; the planet carrier includes an inner ring and an outer ring coaxially arranged, and a connection between the two rings Rib; the transmission assembly includes two sets of inner and outer planetary gears; the inner planetary gears are double-joint gears, including large and small gears with a common gear shaft, multiple inner planetary gears are evenly distributed on the inner ring; outer planetary gears and The inner planetary gear is arranged correspondingly and fixedly connected to the outer ring by a gear shaft; the inner planetary gear meshes with the sun gear with its pinion gear, the large gear meshes with the inner ring of the outer planetary gear, and the outer ring of the outer planetary gear meshes with the ring gear; The number of sun gear teeth multiplied by the number of inner planetary gear teeth is equal to the number of ring gear teeth multiplied by the number of inner planetary pinion teeth.

As another alternative, the fixed teeth and the input teeth are ring gears with the same specifications, and the fixed teeth are fixedly connected in the casing; the transmission assembly includes a plurality of long planetary gears evenly distributed on the planet carrier. One end of the planetary gear meshes with the fixed tooth, the other end meshes with the input tooth, and the gear shaft of the long planetary gear is fixedly connected with the planet carrier.

The present invention also provides a two-speed transmission, which includes a splitter assembly, a brake and the above-mentioned two-way overrunning clutch; the splitter assembly includes an input member and two splitting members, one of which is fixedly connected with the output member of the two-way overrunning clutch, and the other A splitter component is fixedly connected with the input teeth of the two-way overrunning clutch, and the brake is used to control the input of the two-way overrunning clutch; the input member of the splitter assembly is the input of the two-speed transmission, and the output carrier of the two-way overrunning clutch is the output of the two-speed transmission.

Further, the splitter assembly is a single planetary row, which includes a sun gear, a planetary gear, a planet carrier and a ring gear, wherein the ring gear is fixedly connected to the input ring gear of the two-way overrunning clutch, and the planet carrier is connected to the two-way overrunning clutch. The output planet carrier of the overrunning clutch is fixedly connected.

Preferably, the brake is a multi-disc brake, in which one set of friction plates is connected with the casing, and the other group of friction plates is connected with the input ring gear of the two-way overrunning clutch.

In the present invention, the ratio of the number of teeth rotated by the planetary gear engaged with the fixed teeth to the number of fixed teeth is designed to be equal to the ratio of the number of teeth rotated by the planetary gear engaged with the input teeth to the number of input teeth, that is, the ratio of the two sets of planetary gears The relative displacement ratio is equal; so as to ensure that the input gear can drive the output member through the transmission assembly when the input gear rotates, and the output member cannot drive the input gear to rotate in reverse, so as to realize the one-way transmission of torque, so that the entire system has the function of an overrunning clutch, and through constant meshing The teeth are geared so that they can transmit large moments. Based on this two-way overrunning clutch, a two-speed transmission is designed. This two-speed transmission connects the input member of the splitter assembly with the power source, and directly connects a splitter member of the splitter assembly with the output end of the two-way overrunning clutch to form a transmission path. Y, another diverging member is connected with the input end of the bidirectional overrunning clutch to form a transmission path X, and a brake is provided outside the diverging member. Transmission path X and transmission path Y are in parallel with each other. When the brake is not working, the two transmission paths provide power at the same time to drive together, outputting low-speed and high-torque; when the brake is working, transmission path X is locked and cannot participate in transmission, and path Y alone It transmits power and outputs high-speed and low-torque at this time; that is, the present invention only needs one brake to realize the switching of two gears, has low requirements on the control system, simple and reliable gear shifting, smooth and simple gear shifting process, Without power interruption, it is an ideal transmission for electric vehicles.

Description of the drawings

Figure 1 is an equivalent schematic diagram of the two-way overrunning clutch of the present invention when the relative displacement ratios of the two planet wheels are equal.

Figure 2 is an equivalent schematic diagram showing that the relative displacement ratio of the lower planetary gear is greater than the relative displacement ratio of the upper planetary gear.

Figure 3 is an equivalent schematic diagram where the relative displacement ratio of the lower planetary gear is smaller than the relative displacement ratio of the upper planetary gear.

Fig. 4 is a schematic structural diagram of a preferred embodiment 1 of the two-way overrunning clutch in the present invention.

Figure 5 is a schematic structural diagram of the second preferred embodiment of the two-way overrunning clutch in the present invention.

Fig. 6 is a schematic structural diagram of a preferred embodiment 3 of the two-way overrunning clutch in the present invention.

Fig. 7 is a structural diagram of a preferred embodiment of the two-speed transmission in the present invention.

Figure 8 is a schematic diagram of the equivalent structure of the preferred embodiment of the two-speed transmission in the present invention.

Icon serial number:

a—output planet carrier; b—fixed rack; c—input rack; d—upper planetary gear; e—lower planetary gear;

1—fixed side gear, 2—input side gear, 3—planet gear, 4—planet carrier;

01—gear ring, 02—sun gear, 03—planetary gear II, 031—inner planetary gear, A—large gear, B—pinion gear, 032—outer planetary gear, 04—planet carrier II;

001—fixed ring gear, 002—moving ring gear, 003—long planetary gear, 004—planet carrier Ⅲ;

005-ring gear, 006-planetary gear IV, 007-planet carrier IV, 008-sun gear IV, 009-brake.

detailed description

In the two-way overrunning clutch provided by the present invention, the relative displacement ratio of the planetary gear refers to the ratio of the number of teeth traveled by the planetary gear per unit time and the number of non-planetary gears meshing with it in the double planetary system.

In the double planetary system, when the relative displacement ratios of the two sets of planetary gears are equal, the entire system has the nature of an overrunning clutch, so that there is a one-way transmission of force between the input gear and the planet carrier. That is: the rotation of the input gear can drive the planet carrier to rotate, but the rotation of the planet carrier cannot drive the input gear to rotate in reverse.

For ease of explanation, as shown in Figure 1, when the output planet carrier a moves to the left or right on the fixed rack b under the action of external force, it cannot drive the input rack c to move left or right, because the upper The relative displacement ratio of the planetary gear d and the lower planetary gear e is equal, and there is a unidirectional force transmission characteristic between the input rack and the output planet carrier.

The one-way transmission characteristics between the input rack and the output planet carrier will be demonstrated below.

As shown in Figure 2, the relative displacement ratio of the lower planetary gear is greater than that of the upper planetary gear. Suppose that the upper planetary gear has 100 teeth, the lower planetary gear has 100 teeth, and the lower planetary gear has 10 teeth. Now an external force is used to move the output planetary carrier to the left for a certain distance S, then the upper planetary gear rotates clockwise and the number of teeth is S, at the same time the number of teeth of the lower planetary gear to rotate counterclockwise is 10*S=10S, the distance that the lower planetary gear drives the input rack to move to the right is the number of teeth of the lower planetary gear to rotate counterclockwise minus the number of teeth for the planet carrier to move left , That is, 10S-S=9S, the displacement direction of the input rack and planet carrier is opposite.

As shown in Figure 3, the relative displacement ratio of the lower planetary gear is smaller than that of the upper planetary gear. Assuming that the upper planetary gear has 100 teeth, the upper planetary pinion has 10 teeth, and the lower planetary gear has 100 teeth, now an external force is used to move the output planet carrier to the left for a certain distance S, then the upper planetary gear will rotate clockwise The number of teeth is S, and the lower planetary gear rotates counterclockwise. The number of teeth is S/10=0.1S. The distance that the lower planetary gear drives the input rack to move to the right is the lower planetary gear rotates counterclockwise minus the planet carrier moves to the left, which is 0.1 SS=-0.9S, the input rack actually moves a distance of 0.9S to the left, and the displacement direction of the input rack and planet carrier is the same.

Returning to Figure 1, assuming that the upper planetary gear and the lower planetary gear are both 100 teeth, and now an external force is used to move the output planetary carrier to the left for a certain distance S, the upper planetary gear rotates clockwise and the number of teeth is S, and the lower planetary gear is counterclockwise The number of rotating teeth is also S. The distance that the lower planetary gear drives the input rack to move to the right is the counterclockwise rotation of the lower planetary gear minus the number of teeth that the planet carrier shifts to the left, that is, SS=0, there is no lower planetary gear on the input rack Force, the input gear is stationary.

In summary, when the relative displacement ratio of the lower planetary gear is greater than that of the upper planetary gear, the planet carrier can drive the input rack, and the displacement direction of the input rack is opposite to that of the planet carrier; the current relative displacement ratio of the lower planetary gear is less than that of the upper planetary gear. When the relative displacement ratio of the planet gears, the planet carrier can drive the input rack, and the displacement direction of the input rack is the same as the displacement direction of the planet carrier; when the relative displacement ratios of the two planet wheels are equal, the planet carrier cannot drive the input rack, rack Stand still.

The two-way overrunning clutch disclosed in the present invention includes fixed teeth, input teeth, output members and transmission components.

The first preferred embodiment, as shown in Fig. 4, in this embodiment, the fixed tooth is a fixed half-shaft gear 1, and the half-shaft is fixedly connected with the casing to limit its degree of freedom. The input tooth is the input half shaft gear 2, and the number of the input teeth and the fixed teeth are equal. The transmission assembly includes two sets of planetary gears 3 with the same specifications. Each set of planetary gears includes multiple planetary gears. The two sets of planetary gears are arranged side by side, and the gears at the corresponding positions mesh with each other. One planetary gear meshes with the input half shaft gear, and the other One planetary gear meshes with the fixed side gear. The output member is the planet carrier 4 shared by the two sets of planetary gears, and the gear shafts of the two sets of planetary gears are parallel to each other and are fixedly connected to the output member.

Because the two sets of planetary gears in the transmission assembly are directly meshed, the number of teeth that the two sets of planetary gears pass in a unit time is the same, and because the input teeth and the fixed teeth have the same specifications and the same number of teeth. Therefore, the ratio of the number of teeth rotated by the fixed side planetary gear to the number of fixed teeth per unit time is equal to the ratio of the number of teeth rotated by the input side planetary gear to the number of input teeth, that is, the relative displacement ratio of the two sets of planetary gears in this embodiment It is equal, so as to ensure that the input gear can drive the output member to output through the transmission assembly while the output member can not drive the input gear to rotate in reverse, so that this solution has the function of an overrunning clutch and is transmitted through a constant mesh gear to transmit high torque .

The second preferred embodiment, as shown in Fig. 5, in this embodiment, the fixed teeth are designed as a ring gear 01 fixed in the casing. The input gear is the sun gear 02. The transmission assembly includes two sets of inner and outer planetary gears 03Ⅱ which are evenly distributed on the planet carrier. The inner planetary gear 031 is a double gear including a large gear A and a small gear B. The small gear B meshes with the sun gear 02, and the large gear A and The outer planetary gear 032 meshes, and the outer planetary gear 032 meshes with the ring gear 01. The output member is a planet carrier 04II shared by the two sets of planetary gears. The planet carrier includes an inner ring and an outer ring arranged coaxially, and a connecting rib arranged between the two rings. In this embodiment, the number of teeth of the sun gear multiplied by the number of teeth of the large gear is equal to the number of teeth of the ring gear multiplied by the number of teeth of the pinion, that is, the ratio of the number of teeth rotated by the pinion to the number of teeth of the sun gear is equal to that of the outer planetary gear. The ratio of the number of teeth to the number of ring gear teeth.

When the sun gear rotates as input, it drives the inner and outer planet gears to rotate, while the ring gear is fixed, the planet carrier will also rotate and output; when the input sun gear stops rotating, the planet carrier can also be under the action of inertia It rotates freely and does not drive the input sun gear. This scheme has the function of an overrunning clutch, and is transmitted through a constant mesh gear so as to transmit a large torque.

Preferred embodiment three, as shown in Fig. 6, the fixed tooth in this embodiment is a fixed gear ring 001 fixed in the casing. The input tooth is a movable ring gear 002, and its specification is the same as that of the fixed tooth. The transmission assembly includes two sets of planetary gears evenly distributed on the planet carrier, and the two sets of planetary gears are merged into a set of long planetary gears 003. One end of the long gear 003 meshes with the fixed teeth and the other end meshes with the output teeth. The gear shaft and The planet carrier 004Ⅲ as the output member is fixedly connected.

In the working process of this embodiment, since the fixed teeth and the input teeth have the same specifications, and the transmission assembly is a long planetary gear, the relative displacement ratios of the two sets of planetary gears are also equal. When the movable ring gear rotates input, it drives the long planetary gear to rotate, and the planet carrier also rotates and outputs at this time; when the movable ring gear stops input, the planet carrier rotates freely under the action of inertia and will not drive the movable ring gear, so this solution It has the function of an overrunning clutch, and is transmitted through a constant mesh gear to transmit a large torque.

In the above several embodiments, the relative displacement ratios of the planetary gears meshing with the fixed teeth and the planetary gears meshing with the input teeth are designed to be equal; to ensure that the input gear can drive the output member to output through the transmission assembly, and when the input gear stops During input, due to the relative displacement ratio, it is equivalent to separating the input gear from the transmission assembly, so that the transmission assembly continues to rotate without affecting the input gear, so that the entire system has the function of an overrunning clutch and is transmitted through a constant mesh gear to transmit large Moment. This solution is not only suitable for electromechanical integration and other products like the existing overrunning clutch, but also suitable for the driving system of automobiles instead of differentials to improve the driving safety of automobiles under bad road conditions. It can also be applied to multi-axle In the transmission vehicle, the structure of the vehicle transmission system is simplified.

Based on the third preferred embodiment, the present invention also discloses a two-speed transmission. As shown in Fig. 7, the two-speed transmission includes a two-way overrunning clutch, a splitter assembly and a brake. The splitter assembly is a single planetary row, the sun gear 008IV of the single planetary row is used as the input member of the splitter assembly, the planet carrier 007IV is used as the first splitter member, and the ring gear 005 is used as the second splitter member. The planetary wheel 006IV is at the same time as the sun gear 008IV and ring gear. 005 meshing. The planet carrier 007IV of the single planetary row and the planet carrier 004Ⅲ of the two-way overrunning clutch are fixedly connected, the ring gear 005 of the single planetary row and the movable ring gear 002 of the two-way overrunning clutch are fixedly connected, and the brake 009 is used to control the ring gear 005 of the single planetary row. The single planetary sun gear 008IV is the input end of the two-speed transmission, and the planet carrier 004Ⅲ of the two-way overrunning clutch is the output end of the two-speed transmission. The brake 009 is selected as a multi-disc brake. One set of friction plates is connected with the casing, and the other group of friction plates is connected with the second shunt member of the shunt assembly to control the transmission path X to be in a transmission state or a locked state.

When this two-speed transmission is working, the power of the prime mover is input through the sun gear 008IV, and then transmitted to the first splitting member planet carrier 007IV and the second splitting member ring gear 005 through the planetary gears 006IV, and is split into two transmissions The power is combined by the two-way overrunning clutch and then output through the planet carrier 004Ⅲ. One of the transmission paths X is: sun gear 008Ⅳ, planet gear 006Ⅳ, ring gear 005, movable gear ring 002, long planet gear 003, and planet carrier 004Ⅲ. Another transmission path Y is: sun gear 008Ⅳ, planet gear 006Ⅳ, planet carrier 007Ⅳ, and planet carrier 004Ⅲ. The brake 009 is used to control whether the transmission path X participates in the transmission of power. When the brake 009 is not braking, the transmission path X and the transmission path Y transmit power at the same time. At this time, the transmission is in the first gear state and outputs low speed and high torque; when the brake 009 performs braking When moving, the transmission path X is locked and cannot transmit power, and only the transmission path Y transmits alone. At this time, the transmission is in the second gear state and outputs high speed and low torque.

In this embodiment, since the ring gear 005 and the movable ring gear 002 are fixedly connected, the two ring gears can be the same component; the planet carrier 007IV and the planet carrier 004Ⅲ are fixedly connected, so the two planet carriers can also be the same component . That is, this two-speed transmission can be simplified to the structure shown in FIG. 8.

The two-speed transmission provided by the present invention can switch between two gears with only one brake, has low requirements on the control system, simple and reliable shifting methods, smooth and simple shifting process, and no power during shifting. Interruption is the ideal transmission for electric vehicles.

Claims

A two-way overrunning clutch, which is characterized in that it includes input teeth, fixed teeth, transmission components and output components;

The output component is a planet carrier;

The transmission assembly includes several sets of planetary gears arranged on the output member, the input end of which meshes with the input teeth, and the other end meshes with the fixed teeth;

In unit time, the ratio of the number of teeth rotated by the planetary gear meshed with the fixed teeth to the number of fixed teeth is equal to the ratio of the number of teeth rotated by the planetary gear meshed with the input teeth to the number of input teeth.
The two-way overrunning clutch according to claim 1, characterized in that:

The input tooth and the fixed tooth are both half-shaft gears, the number of teeth of both are equal, and the fixed tooth is fixedly connected with the casing;

The transmission assembly includes two sets of planetary gears with the same specifications. The two sets of planetary gears are arranged side by side and mesh with each other. One set of planetary gears meshes with the input gears, and the other set of planetary gears meshes with the fixed teeth. The planet carrier is fixedly connected.
The two-way overrunning clutch according to claim 1, characterized in that:

The fixed teeth are ring gears fixed in the casing;

The input tooth is a sun gear;

The planet carrier includes an inner ring and an outer ring arranged coaxially, and a connecting rib arranged between the two rings;

The transmission assembly includes two sets of inner and outer planetary gears; the inner planetary gear is a double gear, including a large gear and a small gear with a common gear shaft, a plurality of inner planetary gears are evenly distributed on the inner ring; the outer planetary gear and the inner planetary gear The wheels are arranged correspondingly and fixedly connected to the outer ring with a gear shaft; the inner planetary gear meshes with the sun gear with its pinion gear, the large gear meshes with the outer planet gear, and the outer planet gear meshes with the ring gear;

The number of sun gear teeth multiplied by the number of inner planetary gear teeth is equal to the number of ring gear teeth multiplied by the number of inner planetary pinion teeth.
The two-way overrunning clutch according to claim 1, characterized in that:

The fixed tooth and the input tooth are ring gears of the same specification, and the fixed tooth is fixedly connected in the casing;

The transmission assembly includes a plurality of long planetary gears evenly distributed on the planet carrier, one end of the long planetary gear meshes with the fixed tooth, the other end meshes with the input tooth, and the gear shaft of the long planetary gear is fixed to the planet carrier.
A two-speed transmission, characterized in that it comprises a splitter assembly, a brake and the two-way overrunning clutch according to claim 4;

The splitter assembly includes an input member and two splitter members. One splitter member is fixedly connected with the output member of the two-way overrunning clutch, and the other splitter member is fixedly connected with the input teeth of the two-way overrunning clutch. The brake is used to control the input of the two-way overrunning clutch; The input member of the splitter assembly is the input of the two-speed transmission, and the output planet carrier of the two-way overrunning clutch is the output of the two-speed transmission.
The two-speed transmission of claim 5, wherein the splitter assembly is a single planetary row, the single planetary row includes a sun gear, a planetary gear, a planet carrier and a ring gear, wherein the ring gear and the two-way overrunning clutch The input ring gear is fixedly connected, and the planet carrier is fixedly connected with the output planet carrier of the two-way overrunning clutch.
The two-speed transmission according to claim 6, wherein the brake is a multi-disc brake, one set of friction plates is connected to the casing, and the other set of friction plates is connected to the input ring gear of the two-way overrunning clutch.