CN220850595U - Transmission mechanism and internal variable speed hub - Google Patents

Abstract

The utility model belongs to the technical field of internal speed changers, and particularly relates to a transmission mechanism and an internal speed change hub. The transmission mechanism provided by the utility model is provided with the two-stage planetary gear mechanism, wherein the second-stage planetary gear mechanism adopts the triple planetary gear, the internal variable-speed hub can provide eight gears, more gears can provide a wider speed range and more accurate power output, and the first-stage planetary gear mechanism is provided with the supporting piece which is arranged in space, so that the deformation of the transmission mechanism can be reduced, and the normal operation of the transmission mechanism is ensured.

Description

Transmission mechanism and internal variable speed hub

Technical Field

The utility model belongs to the technical field of internal speed changers, and particularly relates to a transmission mechanism and an internal speed change hub.

Background

The Chinese patent document CN116353248A discloses a manual-automatic integrated internal speed-changing hub and a bicycle, in particular discloses a six-gear transmission mechanism, wherein the transmission mechanism adopts a two-stage planetary gear mechanism, the planetary gear mechanism of each stage adopts a duplex planetary gear, however, the planetary gear mechanism of each stage has large span, receives large torque and is easy to bend and deform, the gear shifting pawl can be worn, the gear shifting pawl can not effectively lock a sun gear in the long time, the gear-jumping phenomenon is caused, and no space is arranged between the two-stage planetary gear mechanisms to prevent bending deformation.

Accordingly, the prior art is subject to improvement and development.

Disclosure of utility model

The application aims to provide a transmission mechanism and an inner variable speed hub, which can provide more gears, reduce the deformation of the transmission mechanism and ensure the normal operation of the transmission mechanism.

In order to solve the technical problems, the transmission mechanism comprises at least two stages of planetary gear mechanisms and at least one group of clutch structures, wherein the transmission relation of the planetary gear mechanisms is changed by a driving mechanism in a manual and/or automatic mode, so that torque is changed in speed by the planetary gear mechanisms and is selectively output to an output piece through the clutch structures;

The planetary gear mechanism is provided with two stages, namely a first-stage planetary gear mechanism and a second-stage planetary gear mechanism, and the two stages of planetary gear mechanisms are in series transmission;

The second-stage planetary gear mechanism comprises a second sun gear, a third sun gear, a fourth sun gear, a first triple planetary gear, a second transmission member and a third transmission member, wherein the first triple planetary gear is rotatably connected to the second transmission member, the third transmission member is provided with second gear teeth, the first triple planetary gear is provided with seventh gear teeth, eighth gear teeth and ninth gear teeth, the second sun gear is provided with fourth gear teeth, the third sun gear is provided with fifth gear teeth, the fourth sun gear is provided with sixth gear teeth, the fourth gear teeth of the second sun gear are externally meshed with the eighth gear teeth of the first triple planetary gear, the fifth gear teeth of the third sun gear are externally meshed with the ninth gear teeth of the first triple planetary gear, the sixth gear teeth of the fourth sun gear are externally meshed with the tenth gear teeth of the first triple planetary gear, and the second gear teeth of the third transmission member are internally meshed with the ninth gear teeth of the first triple planetary gear;

at least one support is arranged between the two planetary gear mechanisms.

Further, the inner wall of the support member is connected with the mandrel, and the outer wall of the support member is connected with the inner wall of the first transmission member.

Further, the device also comprises a fixing piece, wherein the fixing piece is fixedly connected with the mandrel, and the supporting piece is arranged on the fixing piece.

Further, the support is disposed between the first sun gear and the second sun gear.

Further, the second-stage planetary gear mechanism is in speed-increasing transmission.

Further, a second clutch structure is arranged between the second transmission member and the third transmission member.

Further, the clutch device further comprises a shaft sleeve, the shaft sleeve is connected with the output piece, and a third clutch structure is arranged between the shaft sleeve and the third transmission piece.

Further, the first-stage planetary gear mechanism is in speed-increasing transmission.

Further, the first stage planetary gear mechanism includes a first sun gear, a first planet gear, a first transmission member, and a second transmission member, the first planet gear being rotatably connected to the first transmission member, the second transmission member having a first gear tooth, the first sun gear having a third gear tooth, the first planet gear having a seventh gear tooth, the third gear tooth of the first sun gear being in external engagement with the seventh gear tooth of the first planet gear, the first gear tooth of the second transmission member being in internal engagement with the seventh gear tooth of the first planet gear.

Further, a first clutch structure is arranged between the first transmission member and the second transmission member.

The application also provides an internal variable speed hub which comprises the transmission mechanism.

From the above, the transmission mechanism of the application has a two-stage planetary gear mechanism, wherein the second-stage planetary gear mechanism adopts a triple planetary gear, the inner variable-speed hub can provide eight gears, more gears can provide a wider speed range and more accurate power output, the first-stage planetary gear mechanism is provided with a supporting piece in space, the supporting piece can reduce the deformation of the transmission mechanism, and the normal work of the transmission mechanism is ensured.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application. The objectives and other advantages of the application will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

Drawings

Fig. 1 is a longitudinal section of the transmission mechanism of the present application.

Fig. 2 is a power transmission path of one gear of the inner shift drum according to the present application.

Fig. 3 is a power transmission path of the second gear of the inner shift drum according to the present application.

Fig. 4 is a power transmission path of three gears of the internal shift drum according to the present application.

Fig. 5 is a power transmission path of the four-gear shift drum in the present application.

Fig. 6 is a power transmission path of five gears of the inner shift drum according to the present application.

Fig. 7 is a power transmission path of six gears of the inner shift drum according to the present application.

Fig. 8 is a power transmission path of seven gears of the inner shift drum of the present application.

Fig. 9 is a power transmission path of eight speeds of the inner shift drum according to the present application.

Description of the reference numerals: 1-first transmission member, 11-input member mounting groove, 12-first mounting groove, 13-first clutch structure, 2-second transmission member, 21-first gear tooth, 22-second mounting groove, 23-second clutch structure, 3-third transmission member, 31-second gear tooth, 32-third clutch structure, 4-first sun gear, 41-third gear tooth, 5-support member, 6-fixing member, 7-second sun gear, 71-fourth gear tooth, 8-third sun gear, 81-fifth gear tooth, 9-fourth sun gear, 91-sixth gear tooth, 10-first planetary gear, 101-seventh gear tooth, 11-first triple planetary gear, 111-eighth gear tooth, 112-ninth gear tooth, 113-tenth gear tooth, 12-shaft sleeve.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present utility model and are not to be construed as limiting the present utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more of the described features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically connected, electrically connected or can be communicated with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present utility model, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

The following disclosure provides many different embodiments, or examples, for implementing different features of the utility model. In order to simplify the present disclosure, components and arrangements of specific examples are described below. They are, of course, merely examples and are not intended to limit the utility model. Furthermore, the present utility model may repeat reference numerals and/or letters in the various examples, which are for the purpose of brevity and clarity, and which do not themselves indicate the relationship between the various embodiments and/or arrangements discussed. In addition, the present utility model provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

Fig. 1 shows a longitudinal section through a transmission. The transmission mechanism is arranged in the inner variable-speed hub, torque is input from the input part (chain wheel), and is output to the output part (the shell of the inner variable-speed hub) after being changed in speed by the transmission mechanism, so that the aim of changing the transmission ratio is fulfilled. The transmission mechanism comprises at least two stages of planetary gear mechanisms and at least one group of clutch structures. In the present embodiment, there is provided a two-stage planetary gear mechanism, each set of planetary gears including a sun gear, a carrier, a ring gear, and at least one planetary gear, the transmission mechanism specifically including a first transmission member 1, a second transmission member 2, a third transmission member 3, a first sun gear 4, a second sun gear 7, a third sun gear 8, a fourth sun gear 9, a first planetary gear 10, and a first triple planetary gear 11. The first-stage planetary gear mechanism comprises a first sun gear 4, a first planetary gear 10, a first transmission member 1 and a second transmission member 2, and the second-stage planetary gear mechanism comprises a second sun gear 7, a third sun gear 8, a fourth sun gear 9, a first triple planetary gear 11, a second transmission member 2 and a third transmission member 3.

The whole structure of the first transmission member 1 is a hollow cylindrical structure with a large left end diameter and a small right end diameter, an input member mounting groove 11 is formed in the outer peripheral surface of the right end of the first transmission member 1, and the input member is mounted in the input member mounting groove 11 and fastened with the first transmission member 1 so as to transmit torsion. The hollow cylindrical structure at the left side of the first transmission member 1 is internally provided with a first sun gear 4 and a supporting member 5, and the left end and the right end of the first sun gear 4 are limited by check rings.

The outer peripheral surface of the first transmission member 1 is provided with a first mounting groove 12, two opposite groove walls of the first mounting groove 12 are respectively provided with two mounting holes, a pin penetrates through a central hole of the first planetary gear 10, a bearing is used for mounting the first planetary gear 10 in the first mounting groove 12, the pin is limited through check rings at two ends, and the matching relation between parts is as follows: the pin is in interference fit with the mounting hole, the central hole and the bearing of the first planetary gear 10 are respectively in transition fit or clearance fit with the pin, and the first planetary gear 10 can rotate around the axis of the first planetary gear.

The first planetary gear 10 has seventh gear teeth 101, and the first sun gear 4 is mounted directly under the first planetary gear 10, and third gear teeth 41 of the first sun gear 4 are externally engaged with the seventh gear teeth 101 of the first planetary gear 10.

In the present embodiment, since four first mounting grooves 12 are provided, four first planetary gears 10 can be mounted, and the number of first planetary gears 10 depends on the actual operating condition of the transmission mechanism and the load, and in general, the larger the load, the larger the number of first planetary gears 10.

The whole structure of the second transmission member 2 is a hollow cylindrical structure with a small left end diameter and a large right end diameter, a first gear tooth 21 is arranged at the right end opening of the second transmission member 2, the first gear tooth 21 is equivalent to a gear ring of the planetary gear mechanism, and the first gear tooth 21 of the second transmission member 2 is internally meshed with a seventh gear tooth 101 of the first planetary gear 10.

The inside of the hollow cylindrical structure at the left side of the second transmission member 2 is used for installing a second sun gear 7, a third sun gear 8 and a fourth sun gear 9, the second sun gear 7, the third sun gear 8 and the fourth sun gear 9 are installed side by side, and the left end and the right end are limited by check rings.

The second mounting groove 22 has been seted up to the outer peripheral face of second driving medium 2, and two cell walls of second mounting groove 22 have been processed respectively two mounting holes, through inserting the pin in the centre bore of first trigeminy planetary gear 11, bearing install first trigeminy planetary gear 11 in second mounting groove 22, and the pin is spacing through the retaining ring at both ends, and the cooperation relationship between the part has: the pin and the mounting hole interference fit, the centre bore, the bearing of first trigeminy planetary gear 11 respectively with pin transitional fit or clearance fit, first trigeminy planetary gear 11 can rotate around self axis.

The first triple planetary gear 11 is provided with eighth gear teeth 111, ninth gear teeth 112 and tenth gear teeth 113, the ninth gear teeth 112 are arranged centrally, the eighth gear teeth 111 are positioned on the right side of the ninth gear teeth 112, the tenth gear teeth 113 are positioned on the left side of the ninth gear teeth 112, the second sun gear 7, the third sun gear 8 and the fourth sun gear 9 are arranged right below the first triple planetary gear 11, the fourth gear teeth 71 of the second sun gear 7 are externally meshed with the eighth gear teeth 111 of the first triple planetary gear 11, the fifth gear teeth 81 of the third sun gear 8 are externally meshed with the ninth gear teeth 112 of the first triple planetary gear 11, and the sixth gear teeth 91 of the fourth sun gear 9 are externally meshed with the tenth gear teeth 113 of the first triple planetary gear 11.

The leftmost end of the first transmission member 1 is further provided with a first clutch structure 13, the bottom surface of the first clutch structure 13 is connected to the outer peripheral surface of the first transmission member 1, and the top surface of the first clutch structure 13 is connected to the inner peripheral surface of the second transmission member 2. The first clutch structure 13 has the function that when the rotating speed of the first transmission member 1 is higher than that of the second transmission member 2, the first clutch structure 13 is combined, and the torque of the first transmission member 1 and the torque of the second transmission member 2 are the same and are output outwards; when the rotation speed of the second transmission member 2 is higher than that of the first transmission member 1, the first clutch structure 13 is disengaged, and the torque of the second transmission member 2 is output.

By providing the first clutch structure 13 between the first transmission member 1 and the second transmission member 2, torque can be selectively transmitted from the one between the first transmission member 1 (carrier) and the second transmission member 2 (ring gear) with the high rotation speed, so that the effect of changing the transmission ratio is achieved.

The right-hand member opening part of third driving medium 3 is provided with second teeth of a cogwheel 31, and the second teeth of a cogwheel 31 and the ninth teeth of a cogwheel 112 internal gearing of first trigeminy planetary gear 11 of third driving medium 3, and the left end of third driving medium 3 is provided with third clutch structure 32, and the leftmost end of second driving medium 2 still is provided with second clutch structure 23, and the bottom surface of second clutch structure 23 is connected in the outer peripheral face of second driving medium 2, and the top surface of second clutch structure 23 is connected in the inner peripheral face of third driving medium 3. The bottom surface of the third clutch structure 32 is connected to the inner peripheral surface of the third transmission member 3, and the top surface of the third clutch structure 32 is connected to the inner peripheral surface of the sleeve 12.

The sleeve 12 is typically made of steel material, and has a high surface hardness, so that the third clutch structure 32 can be prevented from directly acting on the inner peripheral surface of the output member to generate an indentation.

The first clutch structure 13, the second clutch structure 23, the third clutch structure 32 and the function are identical, and will not be described in detail here.

Fig. 2 shows a power transmission path of a first gear of the inner shift drum of the application.

In the first gear state, the first sun gear 4, the second sun gear 7, the third sun gear 8 and the fourth sun gear 9 are all in a free state. When the input piece inputs torque, the torque passes through the first transmission piece 1, the first transmission piece 1 rotates to drive the first planetary gear 10 to rotate, the first sun gear 4 idles, the rotating speed of the first transmission piece 1 is higher than that of the second transmission piece 2, and the first clutch structure 13 is combined to enable the rotating speeds of the first transmission piece 1 and the second transmission piece 2 to be synchronous, so that the torque of the first transmission piece 1 is transmitted to the second transmission piece 2; similarly, the second transmission member 2 rotates to drive the first triple planetary gear 11 to rotate, the second sun gear 7, the third sun gear 8 and the fourth sun gear 9 idle, and the second clutch structure 23 and the third clutch structure 32 are combined at the same time, so that the torque of the second transmission member 2 is transmitted to the third transmission member 3 and then transmitted to the shaft sleeve 12, the shaft sleeve 12 is fastened with the output member, and the output member outputs to the wheel. The inner shift drum at this time is not shifted through the two-stage planetary gear mechanism, and the gear ratio is defined as a first gear ratio.

Fig. 3 shows the power transmission path of the second gear of the inner shift drum of the application.

In the second gear state, the second sun gear 7 is locked, and the first sun gear 4, the third sun gear 8 and the fourth sun gear 9 are in a free state. When the torque is input by the input member, the torque passes through the first transmission member 1, the first transmission member 1 rotates to drive the first planetary gear 10 to rotate, the first sun gear 4 idles, the first clutch structure 13 is combined to enable the rotation speed of the first transmission member 1 and the rotation speed of the second transmission member 2 to be synchronous, the second transmission member 2 rotates to drive the first triple planetary gear 11 to rotate, the fourth gear 71 of the second sun gear 7 is externally meshed with the eighth gear 111 of the first triple planetary gear 11, the rotation speed of the third transmission member 3 is higher than the rotation speed of the second transmission member 2, the second clutch structure 23 is separated from working, the third clutch structure 32 is combined, the torque is transmitted to the shaft sleeve 12 by the third transmission member 3, the shaft sleeve 12 is fastened with the output member, and the output member is output to the wheels. The internal shift drum gear ratio at this time is defined as the second gear ratio.

Fig. 4 shows the power transmission path of three gears of the inner shift drum of the application.

In the third gear state, the third sun gear 8 is locked, and the first sun gear 4, the second sun gear 7, and the fourth sun gear 9 are in a free state. When the torque is input by the input member, the torque passes through the first transmission member 1, the first transmission member 1 rotates to drive the first planetary gear 10 to rotate, the first sun gear 4 idles, the first clutch structure 13 is combined to enable the rotation speed of the first transmission member 1 and the rotation speed of the second transmission member 2 to be synchronous, the second transmission member 2 rotates to drive the first triple planetary gear 11 to rotate, the fifth gear teeth 81 of the third sun gear 8 are externally meshed with the ninth gear teeth 112 of the first triple planetary gear 11, the rotation speed of the third transmission member 3 is higher than the rotation speed of the second transmission member 2, the second clutch structure 23 is separated from working, the third clutch structure 32 is combined, the torque is transmitted to the shaft sleeve 12 by the third transmission member 3, the shaft sleeve 12 is fastened with the output member, and the output member is output to the wheel. The internal shift drum gear ratio at this time is defined as the third gear ratio.

Fig. 5 shows the power transmission path of the four gears of the inner shift drum of the application.

In the fourth gear state, the fourth sun gear 9 is locked, and the first sun gear 4, the second sun gear 7, and the third sun gear 8 are in a free state. When the torque is input by the input member, the torque passes through the first transmission member 1, the first transmission member 1 rotates to drive the first planetary gear 10 to rotate, the first sun gear 4 idles, the first clutch structure 13 is combined to enable the rotation speed of the first transmission member 1 and the rotation speed of the second transmission member 2 to be synchronous, the second transmission member 2 rotates to drive the first triple planetary gear 11 to rotate, the sixth gear teeth 91 of the fourth sun gear 9 are externally meshed with the tenth gear teeth 113 of the first triple planetary gear 11, the rotation speed of the third transmission member 3 is higher than the rotation speed of the second transmission member 2, the second clutch structure 23 is separated from working, the third clutch structure 32 is combined, the torque is transmitted to the shaft sleeve 12 by the third transmission member 3, the shaft sleeve 12 is fastened with the output member, and the output member is output to the wheel. The internal shift drum gear ratio at this time is defined as the fourth gear ratio.

Fig. 6 shows the power transmission path of five gears of the inner shift drum of the application.

In the five-gear state, the first sun gear 4 is locked, and the second sun gear 7, the third sun gear 8 and the fourth sun gear 9 are all in a free state. When the input piece inputs torque, the torque passes through the first transmission piece 1, the first transmission piece 1 rotates to drive the first planetary gear 10 to rotate, the third gear teeth 41 of the first sun gear 4 are externally meshed with the seventh gear teeth 101 of the first planetary gear 10, the rotating speed of the second transmission piece 2 is higher than that of the first transmission piece 1, the first clutch structure 13 is separated from the non-working state, the second transmission piece 2 rotates to drive the first triple planetary gear 11 to rotate, the second clutch structure 23 and the third clutch structure 32 are combined simultaneously, the torque of the second transmission piece 2 is transmitted to the third transmission piece 3 and then transmitted to the shaft sleeve 12, the shaft sleeve 12 is fastened with the output piece, and the output piece outputs the torque to wheels. The internal shift drum gear ratio at this time is defined as the fifth gear ratio.

Fig. 7 shows a six-speed power transmission path of the inner shift drum of the application.

In the six-speed state, the first sun gear 4 and the second sun gear 7 are locked, and the third sun gear 8 and the fourth sun gear 9 are in a free state. When the torque is input by the input member, the torque passes through the first transmission member 1, the first transmission member 1 rotates to drive the first planetary gear 10 to rotate, the third gear teeth 41 of the first sun gear 4 are externally meshed with the seventh gear teeth 101 of the first planetary gear 10, the rotating speed of the second transmission member 2 is higher than that of the first transmission member 1, at the moment, the first clutch structure 13 is separated from working, the second transmission member 2 rotates to drive the first triple planetary gear 11 to rotate, the fourth gear teeth 71 of the second sun gear 7 are externally meshed with the eighth gear teeth 111 of the first triple planetary gear 11, the second clutch structure 23 is separated from working, the third clutch structure 32 is combined, the torque is transmitted to the shaft sleeve 12 by the third transmission member 3, the shaft sleeve 12 is fastened with the output member, and the output member outputs to the wheels. The internal shift drum gear ratio at this time is defined as the sixth gear ratio.

Fig. 8 shows a seven-speed power transmission path of the inner shift drum of the application.

In the seven-gear state, the first sun gear 4 and the third sun gear 8 are locked, and the second sun gear 7 and the fourth sun gear 9 are in a free state. When the input piece inputs torque, the torque passes through the first transmission piece 1, the first transmission piece 1 rotates to drive the first planetary gear 10 to rotate, the third gear teeth 41 of the first sun gear 4 are externally meshed with the seventh gear teeth 101 of the first planetary gear 10, the rotating speed of the second transmission piece 2 is higher than that of the first transmission piece 1, the first clutch structure 13 is separated from working, the second transmission piece 2 rotates to drive the first triple planetary gear 11 to rotate, the fifth gear teeth 81 of the third sun gear 8 are externally meshed with the ninth gear teeth 112 of the first triple planetary gear 11, the rotating speed of the third transmission piece 3 is higher than that of the second transmission piece 2, the second clutch structure 23 is separated from working, the third clutch structure 32 is combined, the torque is transmitted to the shaft sleeve 12 by the third transmission piece 3, the shaft sleeve 12 is fastened with the output piece, and the output piece is output to the wheels. The internal shift drum gear ratio at this time is defined as a seventh gear ratio.

Fig. 9 shows the power transmission path of eight speeds of the inner shift drum of the application.

In the eight-speed state, the first sun gear 4 and the fourth sun gear 9 are locked, and the second sun gear 7 and the third sun gear 8 are in a free state. When the input member inputs torque, the torque passes through the first transmission member 1, the first transmission member 1 rotates to drive the first planetary gear 10 to rotate, the third gear teeth 41 of the first sun gear 4 are externally meshed with the seventh gear teeth 101 of the first planetary gear 10, the rotating speed of the second transmission member 2 is higher than that of the first transmission member 1, the first clutch structure 13 is separated from working, the second transmission member 2 rotates to drive the first triple planetary gear 11 to rotate, the sixth gear teeth 91 of the fourth sun gear 9 are externally meshed with the tenth gear teeth 113 of the first triple planetary gear 11, the rotating speed of the third transmission member 3 is higher than that of the second transmission member 2, the second clutch structure 23 is separated from working, the third clutch structure 32 is combined, the third transmission member 3 transmits torque to the shaft sleeve 12, the shaft sleeve 12 is fastened with the output member, and the output member is output to the wheels. The internal shift drum gear ratio at this time is defined as the eighth gear ratio.

In the whole transmission process of the internal variable-speed hub, except for one gear, the internal variable-speed hub is input by a planet carrier, fixed by a sun gear and output by a gear ring, so that the internal variable-speed hub is in speed-increasing transmission. The first transmission ratio to the eighth transmission ratio are all smaller than or equal to 1, and the lower the gear is, the lower the rotating speed is, the larger the torque is, so the transmission is suitable for climbing slopes or being used when the carrying capacity is large; the higher the gear is, the higher the rotating speed is, the smaller the torque is, so the device is suitable for being used in downhill or when the carrying capacity is small. To increase gear shifting smoothness, the first to eighth gear ratios may be fitted to a binary first order equation by reasonably adjusting the number of teeth of the first to tenth gear teeth 21 to 113.

As can be seen from fig. 2 to 9, all power transmission paths from first gear to eighth gear need to pass through the first transmission member 1, the first transmission member 1 has a large span, is subjected to a large torque, and is easy to bend and deform, if the first transmission member 1 is deformed, the position of the first planetary gear 10 mounted on the first transmission member 1 is shifted, and further the first sun gear 4 is shifted, so that the abrasion of the shift pawl by the locking groove of the first sun gear 4 is increased, the shift pawl cannot effectively lock the sun gear over time, and a skip phenomenon is caused. By arranging the support 5 between the two planetary gear sets, in particular by arranging the support 5 between the first sun gear 4 and the second sun gear 7, the inner wall of the support 5 is connected to the spindle and the outer wall of the support 5 is connected to the inner wall of the first transmission 1. The support 5 is capable of bearing radial load and axial load, reducing the deformation of the first transmission member 1 when the first transmission member 1 is subjected to torque, ensuring concentricity of the first transmission member 1 and the mandrel, and reducing abrasion of the shift pawl. The support 5 may be a deep groove ball bearing, an angular contact ball bearing, a thrust bearing, or the like.

Because the mandrel of the internal variable speed hub is provided with the gear shifting pawl seat or is directly machined, the supporting piece 5 is inconvenient to directly install on the mandrel, the fixing piece 6 is arranged, the supporting piece 5 is firstly installed on the fixing piece 6, and then the fixing piece 6 is fixedly installed on the mandrel, so that the machining difficulty is reduced. The fixing member 6 has a structure capable of being engaged to the shift pawl seat and is capable of fitting the outer circumferential surface of the support member 5.

Therefore, the transmission mechanism provided by the application is provided with the two-stage planetary gear mechanism, wherein the second-stage planetary gear mechanism adopts the triple planetary gear, the inner speed-changing hub can provide eight gears, more gears can provide a wider speed range and more accurate power output, the first-stage planetary gear mechanism is provided with the supporting piece 5 in a space, and the supporting piece 5 can reduce the deformation of the transmission mechanism and ensure the normal work of the transmission mechanism.

In the description of the present specification, reference to the terms "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

What has been described above is merely some embodiments of the present utility model. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit of the utility model.

Claims (11)

1. The transmission mechanism is characterized by comprising at least two stages of planetary gear mechanisms and at least one group of clutch structures, wherein the driving mechanism changes the transmission relation of the planetary gear mechanisms in a manual and/or automatic mode, so that torque is changed in speed by the planetary gear mechanisms and is selectively output to an output piece through the clutch structures;

The planetary gear mechanism is provided with two stages, namely a first-stage planetary gear mechanism and a second-stage planetary gear mechanism, and the two stages of planetary gear mechanisms are in series transmission;

The second-stage planetary gear mechanism comprises a second sun gear (7), a third sun gear (8), a fourth sun gear (9), a first triple planetary gear (11), a second transmission member (2) and a third transmission member (3), wherein the first triple planetary gear (11) is rotatably connected to the second transmission member (2), the third transmission member (3) is provided with second gear teeth (31), the first triple planetary gear (11) is provided with seventh gear teeth (101), eighth gear teeth (111) and ninth gear teeth (112), the second sun gear (7) is provided with fourth gear teeth (71), the third sun gear (8) is provided with fifth gear teeth (81), the fourth sun gear (9) is provided with sixth gear teeth (91), the fourth gear teeth (71) of the second sun gear (7) are in external engagement with eighth gear teeth (111) of the first triple planetary gear (11), the fifth gear teeth (81) of the third sun gear (8) are in external engagement with the eighth gear teeth (111) of the fourth triple planetary gear (11), the fifth gear teeth (81) of the fourth planetary gear (9) are in external engagement with the eighth gear teeth (113) of the fourth triple planetary gear (11), the second gear teeth (31) of the third transmission member (3) are internally meshed with the ninth gear teeth (112) of the first triple planetary gear (11);

At least one support (5) is arranged between the two planetary gear mechanisms.

2. A transmission according to claim 1, characterized in that the inner wall of the support (5) is connected to the spindle, and the outer wall of the support (5) is connected to the inner wall of the first transmission member (1).

3. The transmission mechanism according to claim 1, further comprising a fixing member (6), the fixing member (6) being fixedly connected to the spindle, the support member (5) being mounted on the fixing member (6).

4. A transmission according to claim 1, characterized in that the support (5) is arranged between the first sun gear (4) and the second sun gear (7).

5. The transmission of claim 1, wherein the second stage planetary gear mechanism is a step-up transmission.

6. A transmission according to claim 1, characterized in that a second clutch structure (23) is arranged between the second transmission member (2) and the third transmission member (3).

7. The transmission mechanism according to claim 1, further comprising a sleeve (12), said sleeve (12) being connected to said output member, a third clutch structure (32) being provided between said sleeve (12) and said third transmission member (3).

8. The transmission of claim 1, wherein the first stage planetary gear mechanism is a step up transmission.

9. The transmission mechanism according to claim 8, characterized in that the first stage planetary gear mechanism comprises a first sun gear (4), a first planetary gear (10), a first transmission member (1) and a second transmission member (2), the first planetary gear (10) being rotatably connected to the first transmission member (1), the second transmission member (2) having first gear teeth (21), the first sun gear (4) having third gear teeth (41), the first planetary gear (10) having seventh gear teeth (101), the third gear teeth (41) of the first sun gear (4) being in external engagement with the seventh gear teeth (101) of the first planetary gear (10), the first gear teeth (21) of the second transmission member (2) being in internal engagement with the seventh gear teeth (101) of the first planetary gear (10).

10. A transmission according to claim 9, characterized in that a first clutch structure (13) is arranged between the first transmission member (1) and the second transmission member (2).

11. An internal shift drum comprising a transmission mechanism according to any one of claims 1 to 10.