CN114408084A

CN114408084A - Mid-set motor and electric bicycle

Info

Publication number: CN114408084A
Application number: CN202111542941.4A
Authority: CN
Inventors: 周佳林; 范清泉; 王洪晓
Original assignee: Guangdong Welling Motor Manufacturing Co Ltd; Welling Wuhu Motor Manufacturing Co Ltd
Current assignee: Guangdong Welling Motor Manufacturing Co Ltd; Welling Wuhu Motor Manufacturing Co Ltd
Priority date: 2021-12-16
Filing date: 2021-12-16
Publication date: 2022-04-29

Abstract

The invention discloses a middle-mounted motor and an electric bicycle, wherein the middle-mounted motor comprises a shell, a torque sensing pedal shaft, a power output part, a motor and a multi-stage planetary reduction mechanism, wherein the torque sensing pedal shaft is rotationally connected with the shell; the moment induction pedal shaft is connected to the power output part through a first overrunning clutch; the motor is arranged on the shell; the multi-stage planetary reduction mechanism is connected to the output end of the motor and is connected to the power output part through a second overrunning clutch. Through adopting multistage planet reduction gears for put motor shape rule in, the outward appearance is whole with moment response pedal axle central symmetry, compact structure, and the reduction ratio is big, satisfies whole car outward appearance demand. And the moment induction pedal shaft and the multi-stage planetary reduction mechanism are respectively connected to the power output part through the first overrunning clutch and the second overrunning clutch, so that manpower and motor power can be simultaneously input, and the independent input is not influenced mutually.

Description

Mid-set motor and electric bicycle

Technical Field

The invention relates to the technical field of power-assisted electric bicycles, in particular to a middle-mounted motor and an electric bicycle.

Background

At present, the urban road congestion problem is more and more serious and the concept of ecological protection is more and more advocated, many people begin to turn to the mode of bicycle trip, and the leisure trip mode of bicycle also receives popular favor of wide youth. In order to make traveling more comfortable, convenient and faster, it has become a trend to improve bicycles into electric or power-assisted bicycles.

In the related art, in the field of power-assisted electric bicycles, how to achieve small volume and high power is always the key point of design and research by perfectly integrating an electric power-assisted core component into a bicycle frame. Most of the existing centrally-mounted motors are irregular in shape and large in size, and the appearance requirement of the whole vehicle is difficult to meet.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides the middle-mounted motor which is small in size and large in power and meets the appearance requirement of the whole vehicle.

The invention also provides an electric bicycle with the middle motor.

The centrally-mounted motor comprises a shell, a torque sensing pedal shaft, a power output part, a motor and a multi-stage planetary reduction mechanism, wherein the torque sensing pedal shaft is rotationally connected with the shell and is connected with the power output part through a first overrunning clutch; the motor is arranged on the shell; the multi-stage planetary reduction mechanism is connected to the output end of the motor and is connected to the power output part through a second overrunning clutch.

The centrally-mounted motor provided by the embodiment of the invention at least has the following beneficial effects: through adopting multistage planet reduction gears for put motor shape rule in, the outward appearance is whole with moment response pedal axle central symmetry, compact structure, and the reduction ratio is big, satisfies whole car outward appearance demand. And the moment induction pedal shaft and the multi-stage planetary reduction mechanism are respectively connected to the power output part through the first overrunning clutch and the second overrunning clutch, so that manpower and motor power can be simultaneously input, and the independent input is not influenced mutually.

According to some embodiments of the present invention, the multi-stage planetary reduction mechanism includes a primary planetary reduction system and a secondary planetary reduction system, the primary planetary reduction system includes a first sun gear, a first ring gear, a first planetary gear, a first planet carrier, the first sun gear is connected to an output end of the motor, and the first ring gear is fixed to the housing; the second-stage planetary reduction system comprises a second sun gear, a second gear ring, a second planet gear and a second planet carrier, the second sun gear is fixedly connected with the first planet carrier, the second gear ring is fixed on the shell, and the second planet carrier is connected with the power output part through a second overrunning clutch.

According to some embodiments of the invention, the first sun gear, the first ring gear and the first planet gear are all straight teeth or all helical teeth.

According to some embodiments of the invention, the second sun gear, the second ring gear and the second planet gears are all straight teeth or all helical teeth.

According to some embodiments of the invention, the first overrunning clutch is of a sprag, roller or ratchet type construction.

According to some embodiments of the invention, the second overrunning clutch is of a sprag, roller or ratchet type construction.

According to some embodiments of the present invention, the torque sensing step shaft includes a torque sensing device and a step shaft, the torque sensing device includes a torque sensing sleeve and a torque sensor, the torque sensor is mounted on the housing, one end of the torque sensing sleeve is fixedly connected to the step shaft, and the other end of the torque sensing sleeve is connected to the power output member through the first overrunning clutch.

According to some embodiments of the invention, the center motor includes a step frequency detecting device connected to the housing for detecting a step frequency of the torque sensitive pedal shaft.

The electric bicycle according to the second aspect embodiment of the present invention includes the center-set motor according to the first aspect embodiment of the present invention.

The electric bicycle provided by the embodiment of the invention at least has the following beneficial effects: by adopting the middle motor in the embodiment of the first aspect of the invention, the overall shape is regular, the overall appearance is centrosymmetric by the moment induction pedal shaft, the structure is compact, the reduction ratio is large, and the appearance requirement of the whole vehicle is met. And the moment induction pedal shaft and the multi-stage planetary reduction mechanism are respectively connected to the power output part through the first overrunning clutch and the second overrunning clutch, so that manpower and motor power can be simultaneously input, and the independent input is not influenced mutually.

According to some embodiments of the invention, the electric bicycle comprises a crankset connected to the power take-off.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The invention is further described with reference to the following figures and examples, in which:

fig. 1 is a schematic view of a center motor according to an embodiment of the present invention;

FIG. 2 is a schematic view of a one-stage planetary reduction system of the multi-stage planetary reduction mechanism shown in FIG. 1;

FIG. 3 is a schematic view of a two-stage planetary reduction system of the multi-stage planetary reduction mechanism shown in FIG. 1;

fig. 4 is a schematic view of an electric bicycle according to an embodiment of the present invention.

Reference numerals:

100. a motor is arranged in the middle; 101. a housing; 102. a motor; 103. a first sun gear; 104. a first ring gear; 105. a first planet gear; 106. a first planet shaft; 107. a first carrier; 108. a second sun gear; 109. a second ring gear; 110. a second planet wheel; 111. a second planet shaft; 112. a second planet carrier; 113. a pedal shaft; 114. a torque sensing sleeve; 115. a torque sensor; 116. a first overrunning clutch; 117. a second overrunning clutch; 118. a power take-off; 119. a chain wheel; 120. a step frequency detection device;

401. a frame; 402. a wheel; 403. a pedal crank; 404. a foot pedal; 405. a chain; 406. a flywheel.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality of means is one or more, the meaning of a plurality of means is two or more, and larger, smaller, larger, etc. are understood as excluding the number, and larger, smaller, inner, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

The power-assisted electric bicycle has been marketed from the first product to the present, developed for twenty years, and has now formed a huge industry. The electric bicycle is not only used as a travel tool, but also as a sport tool, and is deeply favored by the majority of riding enthusiasts.

The booster electric bicycle is a new type two-wheel vehicle, belonging to a kind of bicycle, and uses battery as auxiliary power source, and is equipped with motor, and possesses power auxiliary system, and can implement manpower riding and motor boosting integrated new type transportation means.

In the field of power-assisted electric bicycles, the installation positions of motors are mainly divided into two types, one type is a middle-mounted motor, namely, the motor is installed in the middle position of a bicycle body, namely, the motor in a five-way position, and the motor is called as a middle-mounted motor. Put motor and connected to vehicle frame in to be connected and transmit power through chain and rear wheel, pedal is installed to the both sides of motor simultaneously, and under the condition that the motor does not have the power, the personnel of riding can realize through pedal that the manpower rides, and resistance and normal bicycle do not have the difference.

Another type is mounted in the hub of a bicycle, called a hub motor. Compare in-wheel motor, put the motor and all have great advantage in aspects such as technique and performance. For example, the mid-motor has the advantages that the front and rear weight balance of the whole vehicle can be kept as much as possible, the action of the shock absorber is not influenced, the road impact borne by the motor is smaller, the ultrahigh integration degree can reduce the exposure of unnecessary wire pipes, and therefore the vehicle model is superior to the vehicle model matched with the hub motor in the aspects of off-road controllability, stability, trafficability and the like.

In the related art, most of the centrally-mounted motors are mostly provided with the unfolded gear transmission speed reducing mechanism, and the unfolded gear transmission speed reducing mechanism can be understood that the shafts of the unfolded gear transmission speed reducing mechanism are unfolded in a first-level and first-level manner and are in a tiled cascade state. The multi-stage expansion gear transmission speed reducing mechanism is gradually arranged according to the external meshing of a pair of gears, and the structure is simpler. The unfolding type gear transmission speed reducing mechanism is structurally characterized in that the axes of all shafts provided with gears are all distributed on a plane, the input shaft and the output shaft are not coaxial, and the unfolding type gear transmission speed reducing mechanism can cause the shape of the whole machine to be irregular and the volume to be large, so that the appearance requirement of the whole vehicle is difficult to meet.

Referring to fig. 1 to 4, how the mid-motor 100 and the electric bicycle according to the embodiment of the present invention solve the above problems will be described.

Referring to fig. 1, it can be understood that the centrally-mounted motor 100 according to the embodiment of the present invention includes a housing 101, a pedal shaft 113, a power take-off 118, a first overrunning clutch 116, a motor 102, a second overrunning clutch 117, and a multi-stage planetary reduction mechanism. The housing 101 is configured to be fixedly coupled to the frame 401 so as to ensure stability of the entire centrally-mounted motor 100.

The pedal shaft 113 is inserted into the housing 101 and is rotatably connected to the housing 101, and the first overrunning clutch 116 is disposed between the power output member 118 and the pedal shaft 113. The pedal shaft 113 is used for connecting a pedal crank 403, and the pedal crank 403 is connected with a pedal 404. When a rider steps on the pedal 404, the pedal crank 403 drives the pedal shaft 113 to rotate, the first overrunning clutch 116 works, manpower is transmitted to the power output part 118 through the first overrunning clutch 116, and then the power of the pedal is transmitted to the wheel 402, and finally the wheel 402 is driven to rotate.

The motor 102 is fixedly connected to the housing 101, so that the motor 102 stably provides power to achieve the assisting effect. The multi-stage planetary reduction mechanism is connected to the output end of the motor 102, and the second overrunning clutch 117 is disposed between the output end of the multi-stage planetary reduction mechanism and the power output member 118. The power of the motor 102 is transmitted to the multi-stage planetary reduction mechanism, and the second overrunning clutch 117 works to transmit the power of the motor 102 to the wheels 402, and finally drive the wheels 402 to rotate.

The planetary reduction mechanism is a power transmission mechanism that uses a gear speed converter to reduce the number of revolutions of a motor to a desired number of revolutions and obtain a large torque. The gear with less teeth on the transmission shaft of the planetary reduction mechanism is meshed with the big gear on the output shaft to achieve the purpose of reducing speed. The planetary speed reducing mechanism has small volume, light weight, high bearing capacity, long service life, stable operation and low noise. Has the unique characteristics of power splitting and multi-tooth meshing. In addition, the planetary speed reducing mechanism can enable the input shaft and the output shaft to be coaxial, and the multi-stage planetary speed reducing mechanism can achieve a larger speed reducing ratio.

The middle-mounted motor 100 of the embodiment of the invention adopts the multi-stage planetary reduction mechanism, so that the middle-mounted motor 100 has a regular shape, a compact structure and a large reduction ratio, and meets the appearance requirement of the whole vehicle. The whole machine has the characteristics of small structural size, large output torque, large speed ratio, high efficiency, safe and reliable performance and the like.

In addition, by using the first overrunning clutch 116, under the condition that the motor 102 outputs power and the rider does not step on the pedal, the phenomenon that the pedal shaft 113 forms magnetic resistance or mechanical resistance on the multi-stage planetary reducer is eliminated, and therefore it is ensured that extra resistance on the motor 102 is not increased when the rider does not step on the pedal. By using the second overrunning clutch 117, when the motor 102 stops operating, the phenomenon that the motor 102 and the multi-stage planetary reduction mechanism cause magnetic resistance or mechanical resistance to the pedal shaft 113 is eliminated, and further, when the motor 102 does not assist, it is ensured that extra resistance to a riding person is not increased.

It can be understood that, the pedal shaft 113 is driven by manpower to rotate positively, and when the motor 102 does not provide assistance to the power output member 118, the pedal shaft 113 can drive the first overrunning clutch 116 to work, and the manpower is transmitted to the power output member 118 through the first overrunning clutch 116, and at this moment, the second overrunning clutch 117 idles, and the manpower does not influence the multistage planetary reduction mechanism, and the power output member 118 is driven by manpower pedal to rotate. In addition, when the rider stops pedaling or rotates the pedal 404 in the reverse direction, the pedal shaft 113 rotates in the reverse direction relative to the first overrunning clutch 116, i.e., the pedal shaft 113 does not transmit power to the power output member 118. In addition, when the motor 102 outputs power and the rider does not step on the pedal, the motor 102 rotates in the forward direction and is delivered to the power output member 118, the first overrunning clutch 116 idles, and the motor 102 does not affect the pedal shaft 113. That is, when the pedal shaft 113 is rotated forward by the manual force, the first overrunning clutch 116 supplies power to the power output member 118, and when the pedal shaft 113 is rotated in the reverse direction or does not rotate relatively, the pedal shaft 113 and the first overrunning clutch 116 rotate relatively, that is, the pedal shaft 113 does not transmit resistance to the power output member 118.

It will be appreciated that when the motor 102 is rotating in the forward direction, the pto 118 can be driven by the second overrunning clutch 117 to rotate in the forward direction. In addition, when the pedal shaft 113 drives the power output member 118 to rotate and the motor 102 does not provide assistance to the power output member 118 at the same time, the second overrunning clutch 117 idles, that is, the power output member 118 can rotate relative to the second overrunning clutch 117 at this time, and the rotation of the pedal shaft 113 is not affected. When the rotation direction of the motor 102 relative to the second overrunning clutch 117 is reversed, the motor 102 does not transmit power to the power output member 118 at this time. That is, the motor 102 provides an assist force to the power take-off 118 via the second overrunning clutch 117 when rotating in the forward direction relative to the second overrunning clutch 117, and the motor 102 and the second overrunning clutch 117 rotate relative to each other when the motor 102 rotates in the reverse direction or does not rotate relative to the second overrunning clutch 117, that is, the motor 102 does not transmit a resistance force to the power take-off 118.

It should be noted that, when the pedal shaft 113 rotates in the forward direction and/or the motor 102 rotates in the forward direction and drives the power output member 118, the electric bicycle is in the forward running state.

It is understood that the first overrunning clutch 116 may be of a sprag, roller or ratchet type construction. The second overrunning clutch 117 may also be of a sprag, roller or ratchet type construction.

One-way clutches are those which lock one of the operating members so that it can only rotate in one direction. That is, the pedal 404 is positively rotated by the manual force to drive the wheel 402 to positively rotate, so as to move the bicycle forward. But the wheels 402 do not reverse when the foot pedal 404 reverses.

An overrunning clutch is a clutch which is automatically engaged and disengaged by using the rotation speed change or the rotation direction change of a driving part and a driven part. When the driving part drives the driven part to rotate together, the state is called a combined state; when the driving member and the driven member are disengaged to revolve at their respective speeds, an overrun condition is referred to.

The overrunning clutch is a special mechanical clutch which is automatically combined or separated by the change of the relative motion speed or the change of the rotation direction of a main driven part in the mechanical transmission. The driving element can only rotate the driven element from a single direction, and if the driving element changes direction, the driven element is automatically disengaged and does not transmit power, so the clutch is also called a one-way clutch or a one-way bearing. Typically selected at an over-running speed and therefore collectively referred to as an overrunning clutch.

The overrunning clutch has the following functions:

a. the fast and slow switching and overrunning functions are realized in the fast feeding machine.

b. The indexing function of step gap movement and accurate positioning is realized.

c. When the self-locking ball screw is matched with a ball screw or other components, the self-locking ball screw is prevented from reversing, and the self-locking and non-return functions are realized.

The common overrunning clutches include three types, namely a ratchet overrunning clutch, a roller overrunning clutch and a wedge overrunning clutch. Sprag overrunning clutches are generally further classified into contact sprag overrunning clutches, non-contact sprag overrunning clutches, and bidirectional sprag overrunning clutches.

The non-contact wedge block overrunning clutch consists of an outer ring, an inner ring, wedge blocks, a fixed check ring, a baffle ring, an end cover, a bearing, a check ring and the like. When the overrunning speed reaches a certain limit, the centrifugal moment of the eccentric wedge overcomes the spring and other resisting moments, so that the wedge is radially separated from the working surface of the inner ring to form a small gap, friction and abrasion are avoided, and the clutch realizes non-contact work. When in use, the inner ring is arranged on the high-speed shaft, and the outer ring is sleeved on the two bearings of the inner ring and is fastened with the two end covers by screws; the raceway between inner ring working face and the outer loop comprises voussoir, fixed retaining ring, bearing and retaining ring, and the torsional spring that resets is respectively on voussoir both ends cylinder, and the one end of torsional spring is inserted in the small-bore of voussoir cross-section, and the other end leans on the retaining pin, and the fixed retaining ring links together inner ring and voussoir device, and the outer loop passes through screw and flange joint.

When the main motor is started, the main speed reduction high-speed shaft is driven to extend to drive the inner ring and the module device to rotate together to generate centrifugal force, a torque is formed on the wedge supporting point, the direction of the torque is opposite to the torque applied to the module by the torsion spring, and the wedge tends to be separated from the outer ring; when the torque generated by the centrifugal force of the wedge block is not enough to overcome the torque applied to the wedge block by the torsion spring, the wedge block is contacted with the working surface of the inner ring to generate relative sliding friction with the outer ring. And the centrifugal force of the wedge block is increased along with the increase of the rotating speed, when the rotating speed of the inner ring reaches or exceeds the minimum non-contact rotating speed of the clutch, the torque generated by the centrifugal force of the wedge block is increased to be larger than the torque applied to the module by the torsion spring, the wedge block is forced to deflect and is separated from the outer ring to realize the frictionless non-contact rotation of the clutch, and the driven member is not driven to rotate at this time.

The directional clutch can only transmit torque in one steering direction, and can be automatically separated when the steering direction is reversed. Of which the more widely used are roller directional clutches. It mainly comprises star wheel, outer lane, spring ejector pin and roller. The spring is used for pressing the roller to the wedge-shaped groove of the star wheel so that the roller is connected with the star wheel and the outer ring.

The roller and the excircle in the roller overrunning clutch can be used as driving wheels. When the planet wheel is a driving part and rotates forwards, the roller is wedged tightly in the groove under the action of friction force, so that the outer circle is driven to rotate together, and the clutch is in an engaged state. When the planet wheel rotates reversely, the roller is pushed to the wider part of the groove under the action of friction force and is not wedged in the groove any more, and the clutch is in a separated state. If the planet is still rotating in the forward direction, but the outer race can still take up more speed than the planet from the other kinematic chain than in the same direction in which the planet is rotating, the clutch is still disengaged.

Ratchet and paw mechanism, a unidirectional intermittent motion mechanism consisting of a ratchet and a pawl. Ratchet mechanisms are used for unidirectional drive in bicycles.

The ratchet mechanism consists of a driving swing rod, a pawl, a ratchet, a non-return pawl and a rack. The driving part is sleeved on the driven shaft fixedly connected with the ratchet wheel in an empty mode and is connected with the driving pawl through a revolute pair. When the driving piece rotates forwards, the driving pawl is inserted into the tooth groove of the ratchet wheel, the ratchet wheel rotates by a certain angle, and at the moment, the non-return pawl slides on the tooth back of the ratchet wheel. When the driving part rotates reversely, the non-return pawl prevents the ratchet wheel from rotating reversely, and the driving pawl can slide on the back of the ratchet wheel teeth, so that the ratchet wheel is still. Therefore, when the driving part continuously swings back and forth, the ratchet wheel does unidirectional intermittent motion.

The teeth of the ratchet wheel are usually one-way teeth, the pawl is hinged on the rocker, and when the rocker rotates in the forward direction, the driving pawl is inserted into the teeth of the ratchet wheel to push the ratchet wheel to rotate in the same direction; when the rocker rotates reversely, the pawl slides on the ratchet wheel, and the ratchet wheel stops rotating. To ensure that the ratchet does not reverse, a non-return pawl is often added to the stationary member. The reciprocating swing of the rocker can be realized by a crank rocker mechanism, a gear mechanism, a swing oil cylinder and the like, and when very small power is transmitted, the pawl is directly driven by an electromagnet. The angle of each rotation of the ratchet is called the stroke. The size of the stroke can be adjusted by changing the structural parameters of the driving mechanism or the position of the gear cover, and the like, and can also be adjusted during the operation. If more precision than one ratchet corresponding angle is desired, a multi-pawl ratchet mechanism may be employed.

The ratchet mechanism can be classified into a tooth type ratchet mechanism and a friction type ratchet mechanism according to structural forms. The friction type ratchet mechanism replaces a pawl in a tooth type ratchet mechanism with an eccentric sector wedge block, and replaces a ratchet with toothless friction.

The ratchet mechanism is classified into an external engagement ratchet mechanism and an internal engagement ratchet mechanism according to the manner of engagement. The pawls or wedges of the external-engagement ratchet mechanism are all mounted outside the ratchet wheel, while the pawls or wedges of the internal-engagement ratchet mechanism are all inside the ratchet wheel. The external-engagement type ratchet mechanism is convenient to machine, install and maintain and is wide in application. The inner engaged ratchet mechanism has the characteristics of compact structure and small overall dimension.

Referring to fig. 1 and 4, it can be understood that the centrally-mounted motor 100 of the embodiment of the present invention further includes a chain wheel 119, the chain wheel 119 is connected to the power take-off 118, and the chain wheel 119 is used for connecting a transmission connecting member such as a chain 405 and is connected to a flywheel 406 through the chain 405, so as to transmit the boosting effect to the wheels 402, and further provide the boosting effect.

Referring to fig. 1, it can be understood that the center-mounted motor 100 according to the embodiment of the present invention further includes a moment detecting device connected to the pedal shaft 113 and detecting a moment acting on the pedal shaft 113. When the pedal shaft 113 receives the pedal force, the moment applied to the pedal shaft 113 can be detected by the moment detecting means.

It is understood that the centrally-mounted motor 100 further includes a controller electrically connected to the torque detection device. The torque detection device can send data of detected torque to the controller. In addition, the controller is electrically connected with the motor 102, and the controller can control the motor 102 to operate according to the received torque data, so as to control the motor 102 to provide power-assisted riding.

Referring to fig. 1, it can be understood that the torque detection device includes a torque sensing sleeve 114 and a torque sensor 115, wherein one end of the torque sensing sleeve 114 is fixedly connected with the pedal shaft 113, and the other end is connected with the power output member 118 through a first overrunning clutch 116. The torque sensor 115 is mounted on the housing 101 to sense the state of the sleeve 114 to obtain the human input parameters.

It is understood that the center-set motor 100 further includes a step-frequency detecting device 120, the step-frequency detecting device 120 is connected to the casing 101, and the step-frequency detecting device 120 is used for detecting the step-frequency of the step-shaft 113. The pedaling frequency detecting device 120 generally employs a pedaling frequency sensor, and is capable of sending detected pedaling frequency data to the controller.

It is to be understood that the multistage planetary reduction mechanism may be a two-stage planetary reduction mechanism, a three-stage planetary reduction mechanism, a four-stage planetary reduction mechanism, or the like, and the two-stage planetary reduction mechanism will be described below as an example.

Referring to fig. 1, it can be understood that the two-stage planetary reduction mechanism includes a first-stage planetary reduction system and a second-stage planetary reduction system, an input end of the first-stage planetary reduction system is connected to an output end of the motor 102, an output end of the first-stage planetary reduction system is connected to an input end of the second-stage planetary reduction system, and an output end of the second-stage planetary reduction system is connected to the second overrunning clutch 117.

Referring to fig. 2, it can be understood that the one-stage planetary reduction system includes a first sun gear 103, a first ring gear 104, a first planet gear 105, and a first planet carrier 107, wherein the first sun gear 103 is used as an input end and is connected with an output end of the motor 102, so that the motor 102 can drive the first sun gear 103 to rotate. The first ring gear 104 is fixed to the housing 101, and the first carrier 107 is connected as an output end to an input end of the secondary planetary reduction system, so that power can be transmitted to the secondary planetary reduction system through the first carrier 107.

It should be noted that, in some embodiments, the first sun gear 103 may also serve as an input end, the first planet carrier 107 is fixed on the casing 101, and the first ring gear 104 serves as an output end.

Referring to fig. 2, it can be understood that the primary planetary reduction system further includes a first planetary shaft 106, the first planetary gear 105 is rotatably connected to the first planetary carrier 107 through the first planetary shaft 106, that is, the first planetary shaft 106 is fixedly connected to the first planetary carrier 107, and the first planetary gear 105 is rotatably connected to the first planetary shaft 106; alternatively, the first planetary shaft 106 is rotatably connected to the first carrier 107, and the first planetary gear 105 is fixedly connected to the first planetary shaft 106. The first planet wheel 105 is meshed with the first sun gear 103 and simultaneously meshed with the first gear ring 104, and when the motor 102 operates, the first planet wheel 105 and the first planet carrier 107 can be sequentially driven to rotate through the first sun gear 103, and then the second-stage planetary reduction system is driven to rotate in the forward direction through the first planet carrier 107.

In the present embodiment, the first sun gear 103 and the first planetary gear 105 are provided by spur gears. Correspondingly, the first gear ring 104 is also provided with straight teeth. It should be appreciated that in other embodiments, the first sun gear 103 and the first planet gear 105 are arranged in a helical gear arrangement, and correspondingly, the first ring gear 104 is also arranged in a helical gear arrangement. The helical teeth are arranged, so that the primary planetary reduction system can bear larger load, the overload capacity of the primary planetary reduction system can be improved, noise is reduced, and movement is more stable.

Referring to fig. 3, it can be understood that the two-stage planetary reduction system includes a second sun gear 108, a second ring gear 109, a second planet gear 110, and a second planet carrier 112, wherein the second sun gear 108 is used as an input end and is fixedly connected to the first planet carrier 107, so that the first planet carrier 107 can drive the second sun gear 108 to rotate. For example, the second sun gear 108 and the first planet carrier 107 are fixedly connected by means of bolts, interference connection, welding, etc., and even directly processed into a whole. The second ring gear 109 is fixed to the housing 101, and the second carrier 112 is connected as an output to the power take-off 118 via a second overrunning clutch 117. And is able to transmit power to the power output member 118 through the second carrier 112.

It should be noted that, in some embodiments, the second sun gear 108 may also serve as an input end, the second planet carrier 112 is fixed on the casing 101, and the second ring gear 109 serves as an output end.

Referring to fig. 3, it can be understood that the two-stage planetary reduction system further includes a second planetary shaft 111, and the second planetary gear 110 is rotatably connected to the second planetary carrier 112 through the second planetary shaft 111, that is, the second planetary shaft 111 is fixedly connected to the second planetary carrier 112, and the second planetary gear 110 is rotatably connected to the second planetary shaft 111; alternatively, the second planet shaft 111 is rotatably connected to the second planet carrier 112, and the second planet gears 110 are fixedly connected to the second planet shaft 111. The second planetary gear 110 is engaged with the second sun gear 108 and engaged with the second gear ring 109, when the motor 102 operates, the second planetary gear 110 and the second planet carrier 112 can be sequentially driven to rotate by the second sun gear 108, and then the power output member 118 is driven to rotate along the forward direction by the second planet carrier 112.

In this embodiment, the second sun gear 108 and the second planet gear 110 are both provided by straight gears. Correspondingly, the second gear ring 109 is also provided with straight teeth. It should be appreciated that in other embodiments, the second sun gear 108 and the second planet gears 110 are arranged in helical gears, and correspondingly, the second ring gear 109 is also arranged in helical gears. The helical teeth are arranged, so that the primary planetary reduction system can bear larger load, the overload capacity of the primary planetary reduction system can be improved, noise is reduced, and movement is more stable.

It can be understood that the housing 101, the pedal shaft 113, the motor 102, the first sun gear 103, the first ring gear 104, the first planet gear 105, the first planet carrier 107, the second sun gear 108, the second ring gear 109, the second planet gear 110, the second planet carrier 112, and the power output member 118 are coaxial through matching and bearings, so that the mid-motor 100 can be made into a structure with a regular shape, and has a small volume and large power, thereby being convenient for meeting the appearance requirement of the whole vehicle.

Referring to fig. 4, it can be understood that the electric bicycle according to the embodiment of the present invention includes a frame 401, wheels 402, a pedal crank 403, pedals 404, a chain 405, a flywheel 406, and the center motor 100 according to the embodiment of the present invention. The arrangement of the frame 401 and the wheel 402 is prior art, and will not be described herein. In addition, center motor 100 is installed in frame 401 to can provide the helping hand to electric bicycle when electric bicycle rides, and then save the personnel's of riding the power of riding. The centrally-mounted motor 100 can be connected to the wheel 402 through a transmission connection member such as a chain 405 and a flywheel 406, so as to transmit the boosting effect to the wheel 402, and further provide the boosting effect. The central motor 100 is connected with a pedal crank 403, and the pedal crank 403 is connected with a pedal 404, so that a rider can apply a pedaling force to drive the electric bicycle to move.

It should be noted that, when the electric bicycle is ridden, the rider can provide a pedaling force through the pedals to drive the electric bicycle, and at the same time, the middle motor 100 can provide an assisting force to the electric bicycle to assist in driving the electric bicycle. Manpower and motor 102 power may be input independently or simultaneously.

When the motor 102 is damaged or loses power in an auxiliary driving mode, the pedal shaft 113 is driven by manpower to rotate in the forward direction, the pedal shaft 113 drives the torque induction sleeve 114 to rotate synchronously, the first overrunning clutch 116 works, the manpower is transmitted to the power output part 118 through the first overrunning clutch 116, the second overrunning clutch 117 idles, the manpower does not influence the second planet carrier 112, and the manpower is output by the power output part 118.

When the manual pedal drives the static pedal or the backward pedal, and the motor 102 works, the power of the motor 102 is synchronously output by the first sun gear 103, and is transmitted to the second planet carrier 112 after being decelerated by the primary planetary deceleration system and the secondary planetary deceleration system. The second overrunning clutch 117 works, the power of the motor 102 is transmitted to the power output member 118 through the second overrunning clutch 117, at the moment, the first overrunning clutch 116 idles, and the power of the motor 102 does not influence the torque sensing sleeve 114. The power of the motor 102 is output by the power take-off 118.

When the motor 102 works normally and is driven by manpower to pedal normally, the pedal shaft 113 is driven by manpower to rotate in the forward direction, the pedal shaft 113 drives the torque sensing sleeve 114 to rotate synchronously, the torque sensor 115 senses the change of the physical state when the torque sensing sleeve 114 is stressed, so that the magnitude of the manpower input is judged, the motor 102 outputs corresponding power according to the magnitude of the manpower input, and the corresponding power is transmitted to the second planet carrier 112 after being decelerated by the primary planetary deceleration system and the secondary planetary deceleration system. The manpower and the power of the motor 102 are transmitted to a power output part 118 through a first overrunning clutch 116 and a second overrunning clutch 117 respectively, and man-machine hybrid power is output by the power output part 118.

When the pedal shaft 113 rotates reversely, the torque sensing sleeve 114 rotates synchronously, the first overrunning clutch 116 is disengaged, no power is output, and the pedal shaft 113 and the torque sensing sleeve 114 idle. When the motor 102 rotates reversely, the power of the motor 102 is synchronously output by the first sun gear 103, is transmitted to the second planet carrier 112 after being reduced by the primary planetary reduction system and the secondary planetary reduction system, the second overrunning clutch 117 is disengaged, no power is output, and the motor 102 idles.

In summary, the embodiment of the invention provides an electric bicycle, which has a regular shape and conforms to the movement shape of a bicycle pedal. The structure is compact, and the power reduction ratio of the motor 102 is large.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.

Claims

1. Put motor in, its characterized in that includes:

a housing;

a power take-off;

the torque sensing pedal shaft is rotationally connected to the shell and is connected to the power output part through a first overrunning clutch;

a motor mounted to the housing;

and the multi-stage planetary speed reducing mechanism is connected to the output end of the motor and is connected to the power output part through a second overrunning clutch.

2. The mid-motor set forth in claim 1, wherein the multistage planetary reduction mechanism includes:

the primary planet speed reducing system comprises a first sun gear, a first gear ring, a first planet gear and a first planet carrier, wherein the first sun gear is connected with the output end of the motor, and the first gear ring is fixed on the shell;

second grade planet deceleration system, including second sun gear, second ring gear, second planet wheel, second planet carrier, second sun gear fixed connection in first planet carrier, the second ring gear is fixed in the shell, the second planet carrier passes through second freewheel clutch connect in power take off spare.

3. The mid-set motor according to claim 2, wherein the first sun gear, the first ring gear, and the first planet gear are all straight teeth or are all helical teeth.

4. The mid-set motor according to claim 2, characterized in that the second sun gear, the second ring gear, and the second planet gears are all straight teeth or are all helical teeth.

5. The mid-motor of claim 1, wherein the first overrunning clutch is of a sprag, roller, or ratchet type construction.

6. The mid-motor of claim 1, wherein the second overrunning clutch is of a sprag, roller or ratchet type construction.

7. The centrally-mounted motor according to claim 1, wherein the torque sensing pedal shaft comprises a torque sensing device and a pedal shaft, the torque sensing device comprises a torque sensing sleeve and a torque sensor, the torque sensor is mounted on the housing, one end of the torque sensing sleeve is fixedly connected with the pedal shaft, and the other end of the torque sensing sleeve is connected with the power output member through the first overrunning clutch.

8. The center motor according to claim 1, characterized in that the center motor includes a step frequency detecting means connected to the housing for detecting a step frequency of the torque sensitive pedal shaft.

9. An electric bicycle comprising the centrally installed motor of any one of claims 1 to 8.

10. The electric bicycle of claim 9, comprising a crankset connected to the power take off.