CN111409760A - A clutch type electric bicycle sprocket drive mechanism - Google Patents

Abstract

The invention discloses a clutch-type electric bicycle sprocket drive mechanism, which comprises a wheel shaft, a motor end disc, a sprocket, an outer end disc and a return spring. The outer end disc, the sprocket and the motor end disc are sequentially installed on the The outer end face of the motor end plate is provided with a ring of teeth; the sprocket and the axle are installed in rotation, and there is a clearance sliding fit between the sprocket and the axle, and the sprocket can slide along the axial direction of the axle; The opposite side of the motor end plate is provided with a locking column matched with the teeth of the motor end plate; a ratchet pawl mechanism for driving the sprocket to approach the motor end plate is arranged between the sprocket and the outer end plate; reset A spring is installed between the sprocket and the motor end plate to provide a restoring force for the sprocket to disengage from the motor end plate. The sprocket will mesh with the motor wheel only in the riding state, which greatly reduces the working time of the sprocket, prolongs the service life of the sprocket, and reduces the running noise of the sprocket to avoid the occurrence of follow-up.

Description

A clutch type electric bicycle sprocket drive mechanism

technical field

The invention belongs to the technical field of electric bicycles, and particularly relates to a clutch-type electric bicycle sprocket driving mechanism.

Background technique

Referring to Figures 6 and 7, the existing bicycle rear wheel drive structure is that the motor wheel is installed on the rear wheel shaft a, and the motor end plate b of the motor wheel is provided with a threaded port b-1 for installing a flywheel (ie, a sprocket). , the flywheel c is installed on the threaded port to realize the fixed installation with the motor wheel, and there is a ring of teeth on the outer ring of the flywheel, so that the outer ring of the flywheel is linked with the crank wheel through the chain to realize chain transmission, and the interior of the flywheel adopts ratchet ratchet The claw structure ensures the one-way transmission of riding. This flywheel transmission structure has the following problems:

1. The flywheel always runs with the motor wheel, which greatly increases the working time of the flywheel. In addition, the flywheel has a ratchet pawl structure to ensure the one-way transmission of riding, which makes the ratchet pawl structure inside the flywheel prone to damage, resulting in the flywheel. The service life is low.

2. After the flywheel works and ages for a long time, it is easy for the crank to follow the rotation (when the motor wheel is running, due to the increase of the internal aging friction of the flywheel, it may drive the outer ring of the flywheel to rotate, and then the outer ring of the flywheel drives the chain to rotate, and the chain drives the crank. Follow-up), the crank’s follow-up will cause the car’s power-assist sensor to send a power-assist signal to the controller, and the controller mistakenly thinks that the customer is using the power-assist function, resulting in a flying car and a hidden danger to the customer’s travel safety.

3. After the flywheel has been aging for a long time, when the motor wheel drives the flywheel to run, there will be a lot of noise.

4. The flywheel is installed on the end plate of the motor through the thread, and the flywheel is easy to withdraw when running for a long time, thus causing a safety hazard.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a clutch-type electric bicycle sprocket drive mechanism.

The present invention is achieved through the following technical solutions:

A clutch-type electric bicycle sprocket drive mechanism, comprising an axle, a motor end disc, a sprocket, an outer end disc and a return spring, and the outer end disc, the sprocket, and the motor end disc are sequentially installed on the axle from outside to inside;

The outer end face of the motor end plate is provided with a ring of teeth;

The sprocket and the axle are rotatably installed, and the sprocket and the axle are in clearance sliding fit, and the sprocket can slide axially along the axle; on the side of the sprocket opposite to the motor end plate, there are teeth with the motor end plate. a cooperating locking post;

A ratchet and pawl mechanism is arranged between the sprocket and the outer end disc. When the sprocket is running in the forward direction, the sprocket is driven to approach the motor end disc through the ratchet pawl mechanism, thereby realizing the connection between the sprocket and the motor end disc. transmission bite;

The return spring is installed between the sprocket and the end plate of the motor, and provides a restoring force for the sprocket to be separated from the end plate of the motor.

In the above technical solution, the outer end disc is fixedly installed on the wheel shaft by means of threads.

In the above technical solution, a ratchet pawl is provided on the inner surface of the outer end plate, and a circle of ratchet teeth is provided on the outer end surface of the sprocket.

In the above technical solution, the top working surface of the ratchet pawl and the tooth surface of the ratchet tooth are inclined surfaces that cooperate with each other.

In the above technical solution, the distance between the teeth on the motor end plate is larger than the diameter of the locking column, so that the locking column can smoothly enter the teeth, and each tooth on the motor end plate is arranged obliquely In this way, after the locking column just enters the teeth, with the operation of the sprocket, even if the sprocket loses the driving action of the ratchet pawl mechanism, the locking column can continue to enter the tooth root under the self-inclined guiding action of the teeth.

In the above technical solution, the number of locking posts on the sprocket is not limited to one, but can be multiple.

In the above technical solution, the specific structure of the sprocket is as follows: it includes a cylinder, the inner wall of the cylinder is provided with a ring of blocking walls, and the outer cylinder cavity of the blocking wall is provided with a bearing, which is installed on the axle through the bearing, and the bearing is connected to the axle. There is a clearance fit between them, which can slide along the axial direction of the wheel shaft; the inner cylinder cavity of the baffle wall is used to install the return spring; the outer wall of the cylinder body is provided with a ring of sprockets for installing the chain; the outer end of the cylinder body is machined out The ratchet teeth are provided on the inner and outer walls of the cylinder body.

In the above technical solution, an installation groove for installing the ratchet pawl is provided on the inner surface of the outer end plate, and the ratchet pawl is installed in the installation groove through a torsion spring.

In the above technical solution, a protective cover is provided on the outer end disc, and the protective cover covers the ratchet teeth and pawls and plays a role of dust protection.

The advantages and beneficial effects of the present invention are:

1. The sprocket of the present invention does not have the risk of wire withdrawal.

2. The sprocket of the present invention will mesh and drive with the motor wheel only in the riding state, thereby greatly reducing the working time of the sprocket and prolonging the service life of the sprocket; Turning happens.

3. There is no ratchet pawl mechanism inside the sprocket of the present invention, thereby increasing the working stability and service life of the sprocket.

4. The sprocket of the present invention is directly installed on the axle. Compared with the traditional sprocket installed on the threaded port of the motor end plate, its inner diameter is smaller. Therefore, it is beneficial to reduce the size of the sprocket and make the vehicle design more beautiful.

Description of drawings

FIG. 1 is a schematic three-dimensional structure diagram of the clutch-type electric bicycle sprocket drive mechanism of the present invention.

FIG. 2 is a cross-sectional view of the clutch-type electric bicycle sprocket drive mechanism of the present invention.

Fig. 3 is a partial enlarged view of the ratchet pawl in the present invention.

FIG. 4 is a schematic diagram of the present invention after a protective cover is provided on the outer end disc.

FIG. 5 is a schematic structural diagram of the sprocket and the outer end disc in a state where the restraint of the pawl and ratchet teeth is lost between the sprocket and the outer end plate of the present invention.

FIG. 6 is a schematic diagram of the structure of a conventional bicycle motor wheel in the background art.

FIG. 7 is a schematic diagram of an existing bicycle motor wheel and flywheel installation structure in the background art.

For those of ordinary skill in the art, other related drawings can be obtained from the above drawings without any creative effort.

Detailed ways

In order to make those skilled in the art better understand the solutions of the present invention, the technical solutions of the present invention are further described below with reference to specific embodiments.

Example 1

Referring to Figures 1-2, a clutch-type electric bicycle sprocket drive mechanism includes an axle 1, a motor end disc 2, a sprocket 3, an outer end disc 4 and a return spring 5.

The motor end plate 2 is rotatably mounted on the axle 1, and a ring of teeth 2-1 is provided on the outer end surface of the motor end plate.

The sprocket 3 is installed on the axle 1, the sprocket 3 is located on the outside of the motor end plate 2, the sprocket 3 and the axle 1 are installed in rotation, and the sprocket 3 and the axle 1 are in clearance sliding fit. It can slide axially along the wheel shaft; a locking column 3-1 is arranged on the opposite side of the sprocket 3 to the motor end plate 2, which is matched with the teeth 2-1 of the motor end plate, and the locking column can be inserted into the motor end plate. Between the teeth, the transmission engagement between the sprocket 3 and the motor end plate 2 is realized.

The outer end disc 4 is fixedly mounted on the axle 1 by means of threads, the outer end disc 4 is located on the outer side of the sprocket 3, a ratchet pawl mechanism is arranged between the sprocket 3 and the outer end disc 4, and the sprocket 3 When running in the forward direction, the sprocket 3 is driven to approach the motor end plate 2 through the ratchet pawl mechanism, thereby realizing the transmission engagement between the sprocket 3 and the motor end plate 2 .

The return spring 5 is installed between the sprocket 3 and the motor end plate 2 , and provides the sprocket 3 with a restoring force in the direction of the outer end plate 4 through the return spring 5 .

Further, the inner surface of the outer end plate 4 (ie the surface of the outer end plate 4 opposite to the sprocket 3 ) is provided with a pawl 4 - 1 , and the outer end surface of the sprocket 3 is provided with a circle of ratchet teeth 3 - 2 . The number of pawls 4-1 is not limited to one, but can be multiple; referring to FIG. 3, the top working surface of the pawl 4-1 and the tooth surface of the ratchet teeth 3-2 are inclined surfaces that cooperate with each other. When the sprocket 3 is driven to run in the forward direction, a relative repulsive force is generated between the top working surface of the pawl 4-1 and the ratchet tooth 3-2, so that the driving sprocket moves along the axle 1 to the motor end plate 2.

Further, the distance between the teeth on the motor end plate 2 is slightly larger than the diameter of the locking column 3-1, so that the locking column can smoothly enter the teeth, and each tooth on the motor end plate is inclined. It is set so that when the locking column just enters between the teeth, with the operation of the sprocket, even if the sprocket 3 loses the driving action of the ratchet pawl mechanism, the locking column 3-1 can continue under the self-inclined guiding action of the teeth. into the root of the tooth.

Further, the number of the locking posts 3-1 on the sprocket 3 is not limited to one, but may be multiple.

Further, the motor end plate 2 is provided with a circle of screw holes (not shown in the figure) for connecting with the motor wheel body by bolts.

Further, the specific structure of the sprocket 3 is as follows: it includes a cylinder, the inner wall of the cylinder is provided with a ring of blocking walls 3-4, and the outer cylinder cavity of the blocking wall is provided with bearings 3-5, which are installed on the axle 1 through the bearings. On the upper side, there is a clearance fit between the bearing and the axle, which can slide along the axial direction of the axle; the inner cylinder cavity of the retaining wall is used to install the return spring 5; the outer wall of the cylinder is provided with a ring of sprockets 3-3 for installation Chain; the outer end of the cylinder (that is, the end of the cylinder opposite to the outer end plate) is machined with ratchet teeth 3-2, and the outer wall of the inner end of the cylinder (that is, the outer wall of the end of the cylinder opposite to the motor end plate) is provided. The locking post 3-1.

Further, an installation groove for installing the ratchet pawl is provided on the inner surface of the outer end plate, and the ratchet pawl is installed in the installation groove through a torsion spring.

Further, referring to FIG. 4 , a protective cover 4-2 is provided on the outer end plate, and the protective cover covers the ratchet teeth and pawls to play a role of dust protection.

Embodiment 2

The operating method of the clutch-type electric bicycle sprocket drive mechanism is as follows:

When the rider rides forward, the chain drives the sprocket to run forward. When the sprocket runs forward, the pawl on the outer end disc will drive the sprocket to approach the motor end disc, so that the locking column on the sprocket enters the motor end. Between the teeth of the disc, as the sprocket continues to run forward, the locking column enters the root of the tooth under the self-guided action of the teeth. Figure 5), does not affect the continued operation of the subsequent sprocket, and then the sprocket drives the entire motor wheel to run, and the car body moves forward.

When the rider stops riding, the sprocket moves to the outside under the action of the return spring, and disengages from the transmission engagement with the teeth of the motor end plate. At this time, the operation of the motor wheel will not drive the sprocket to run synchronously, thus reducing the speed of the sprocket. The working time of the inner bearing is long, which greatly improves its service life.

When the rider steps back on the pedals, the chain drives the sprocket in the reverse direction. At this time, the ratchet teeth on the sprocket press down on the pawl on the outer end plate, and the pawl does not restrict the direction of the sprocket.

For ease of description, spatially relative terms such as "upper", "lower", "left", "right" and the like are used in the embodiments to describe how one element or feature shown in the figures is relative to another element or feature. relation. It should be understood that, in addition to the orientation shown in the figures, spatial terms are intended to encompass different orientations of the device in use or operation. For example, if the device in the figures is turned over, elements described as "below" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "lower" can encompass both upper and lower positions. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative references used herein interpreted accordingly.

Moreover, relational terms such as "first" and "second" etc. are only used to distinguish one element from another having the same name and do not necessarily require or imply any such actual existence between those elements relationship or order.

The present invention has been exemplarily described above. It should be noted that, without departing from the core of the present invention, any simple deformation, modification, or other equivalent replacements that can be performed by those skilled in the art without any creative effort fall into the scope of the present invention. the scope of protection of the invention.

Claims (9)

1. a clutch type electric bicycle sprocket drive mechanism, it is characterized in that: comprise axle, motor end disc, sprocket, outer end disc and return spring, outer end disc, sprocket, motor end disc are installed sequentially from outside to inside on said axle; The outer end face of the motor end plate is provided with a ring of teeth; The sprocket and the axle are rotatably installed, and the sprocket and the axle are in clearance sliding fit, and the sprocket can slide axially along the axle; on the side of the sprocket opposite to the motor end plate, there are teeth with the motor end plate. a cooperating locking post; A ratchet and pawl mechanism is arranged between the sprocket and the outer end disc. When the sprocket is running in the forward direction, the sprocket is driven to approach the motor end disc through the ratchet pawl mechanism, thereby realizing the connection between the sprocket and the motor end disc. transmission bite; The return spring is installed between the sprocket and the end plate of the motor, and provides a restoring force for the sprocket to be separated from the end plate of the motor. 2 . The clutch-type electric bicycle sprocket drive mechanism according to claim 1 , wherein the outer end plate is fixedly mounted on the wheel shaft by means of threads. 3 . 3 . The clutch-type electric bicycle sprocket drive mechanism according to claim 1 , wherein a ratchet pawl is arranged on the inner surface of the outer end plate, and a circle of ratchet teeth is arranged on the outer end surface of the sprocket. 4 . 4 . The clutch-type electric bicycle sprocket drive mechanism according to claim 1 , wherein the top working surface of the pawl and the tooth surface of the ratchet teeth are inclined surfaces that cooperate with each other. 5 . 5. The clutch-type electric bicycle sprocket drive mechanism according to claim 1, wherein the tooth spacing between the teeth on the motor end plate is greater than the diameter of the locking column, and each The teeth are set obliquely. When the locking column has just entered between the teeth, with the operation of the sprocket, even if the sprocket loses the driving effect of the ratchet pawl mechanism, the locking column can continue to enter under the self-inclined guiding action of the teeth. at the root of the tooth. 6 . The clutch-type electric bicycle sprocket drive mechanism according to claim 1 , wherein the number of locking posts on the sprocket is multiple. 7 . 7. The clutch-type electric bicycle sprocket drive mechanism according to claim 1, wherein the specific structure of the sprocket is as follows: comprising a cylinder, the inner wall of the cylinder is provided with a circle of blocking walls, and the outer cylinder of the blocking wall is A bearing is arranged in the cavity, which is installed on the axle through the bearing. There is a clearance fit between the bearing and the axle, which can slide along the axial direction of the axle; the inner cylinder cavity of the blocking wall is used to install the return spring; the outer wall of the cylinder is provided with a The chain teeth are used for installing the chain; the outer end of the cylinder body is machined with ratchet teeth, and the locking column is arranged on the inner end and outer wall of the cylinder body. 8. The clutch-type electric bicycle sprocket drive mechanism according to claim 1, wherein an installation groove for installing the pawl is provided on the inner surface of the outer end plate, and the pawl is installed in the installation groove by a torsion spring. 9 . The clutch-type electric bicycle sprocket drive mechanism according to claim 1 , wherein a protective cover is provided on the outer end plate, and the protective cover covers the ratchet teeth and pawls. 10 .

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