Bicycle center shaft gearbox adopting pin tooth transmission

Abstract

According to the pin tooth transmission and bicycle middle shaft gearbox pin, the pin tooth transmission technology is applied to a bicycle gearbox, a crank main shaft is provided with a set of equidistant cycloidal gears, an auxiliary shaft is provided with a set of pin wheels, the cycloidal gears on the crank main shaft are in anti-rotation connection with the main shaft, and the left end of the crank main shaft is supported on a gearbox left end cover through a bearing; the output sleeve is supported on a right end cover of the gearbox through an outer bearing, and the right end of the output sleeve is connected with a chain wheel chain wheel; a pin wheel on the auxiliary shaft is rotatably connected with an auxiliary shaft sleeve to form a gearbox driven wheel, an axial arc groove is formed in the inner circumferential face of a pin wheel inner sleeve, the two ends of the gearbox auxiliary shaft sleeve are supported on a gearbox end cover through bearings, a set of conical through holes are formed in the auxiliary shaft sleeve in the axial direction, and steel balls are installed in the conical through holes. The left end of the output sleeve is connected with a pin wheel through a spline, and a clutch capable of axially sliding is installed on the inner circumference of the output sleeve and used for controlling lifting of the steel ball, so that the pin wheel needing to output power is selected.

Description

Technical field:

[0001] The technology of the invention belongs to the field of bicycle middle shaft transmission. Background technology:

[0002] The existing bicycle middle shaft transmission technology is gear transmission or sprocket transmission. The gear transmission parts require high processing precision and the parts are heavy and costly. The sprocket transmission has a large overall size. The current bicycle middle shaft transmission market is in urgent need of a product that is small in size, light in weight, low in production cost, and can be mass-produced. Summary of the invention:

[0003] The present invention provides a product technology of a bicycle middle shaft gearbox using pin gear transmission, which is light in weight, small in size, low in production cost and easy to produce in large quantities.

[0004] A bicycle middle shaft gearbox using pin gear transmission, the pin gear transmission technology is applied to the bicycle middle shaft gearbox, a group of pin gear transmission equidistant cycloid gears with different numbers of teeth are arranged on the crank spindle, the cycloid gear with a small number of teeth is installed near the chainring sprocket end, the tooth profile of the cycloid gear is an equidistant cycloid, the gear outer dimensions are equivalent to those of the bicycle sprocket, the cycloid gear is anti-rotationally connected to the crank spindle, and the crank spindle is supported on the gearbox end cover through bearings at both ends.

[0005] The bicycle middle shaft gearbox using pin gear transmission is provided with a group of mutually meshing pin wheels corresponding to the cycloid gear of the crank main shaft on the secondary shaft parallel to the crank main shaft. The pin wheels are riveted assembly structures, and the pin wheels are provided with an inner sleeve. The outer peripheral surface of the inner sleeve of the pin wheel is connected to the pin wheel spoke plate for anti-rotation. The inner peripheral surface of the inner sleeve of the pin wheel is provided with an axial arc groove. The pin wheel is sleeved on the secondary shaft and can be selectively connected to the secondary shaft by a clutch. During operation, only one pin wheel can transmit power, and the remaining pin wheels can rotate freely relative to the secondary shaft. A cycloid gear is connected to the right end of the secondary shaft for anti-rotation, which is used to transmit the power on the secondary shaft after speed change back to the pin wheel on the power output sleeve on the main shaft.

[0006] The power output sleeve is supported on the right end cover of the gearbox through an outer bearing and supports the crankshaft through an inner bearing. The left end of the power output sleeve is anti-rotatably connected to a pin wheel and meshes with the cycloid gear on the secondary shaft to receive the power after the speed change. The right end of the power output sleeve is anti-rotatably connected to the toothed sprocket.

[0007] Furthermore, the secondary shaft parallel to the crankshaft is a hollow shaft, and its two ends are supported on the gearbox end cover by bearings. The secondary shaft is provided with radial conical through holes arranged axially, and steel balls are installed in the radial conical through holes and correspond to the pin wheels. A clutch assembly is installed on the inner circumference of the secondary shaft, and the clutch can slide axially relative to the secondary shaft. The outer circumference of the clutch can control the lifting and lowering of the steel balls to select one of the pin wheels and the secondary shaft to lock the transmission power.

[0008] Furthermore, a radial sliding key is arranged on the inner circumference of the clutch, and the clutch can rotate relative to the radial sliding key. A fixed hollow shaft is installed on the inner circumference of the clutch, and both ends of the fixed hollow shaft are screwed to the gearbox end cover. A radial through groove is arranged in the middle of the fixed shaft along the axial direction, which can accommodate the axial movement of the radial sliding key and limit its rotation. There is a through hole in the middle of the radial sliding key, which can pass through the speed change cable. The turning handle rotates the cable to pull the sliding key to move axially, and the sliding key drives the clutch to move axially to realize manual speed change:

[0009] The pin wheel in the bicycle middle shaft gearbox using pin gear transmission is a riveted assembly structure, which is provided with left and right spokes, an inner sleeve and a pin shaft.

[0010] The same control structure in the bicycle middle shaft gearbox using pin gear transmission can be used for electric control or intelligent control.

[0011] The power transmission route of the gearbox is from the crank main shaft to a group of cycloid gears meshing with a group of pin wheels on the secondary shaft, and a pin wheel is selected through a clutch to output power to the secondary shaft. The cycloid gear on the secondary shaft then transmits power to the pin wheel on the power output sleeve, driving the toothed sprocket to output power to the rear hub of the bicycle. Description of the drawings:

[0012] Figure 1 It is an axonometric drawing of the overall assembly of a bicycle middle shaft gearbox using pin gear transmission.

[0013] Figure 2 It is a cross-sectional view of the overall assembly of a bicycle middle shaft gearbox using pin gear transmission.

[0014] Figure 3 It is an axonometric view of the crank spindle assembly of a bicycle middle shaft gearbox using pin gear transmission.

[0015] Figure 4 It is an axonometric view of the bicycle middle shaft gearbox countershaft assembly using pin gear transmission.

[0016] Figure 5 It is a cross-sectional view of the secondary shaft assembly of a bicycle middle shaft transmission that uses pin gear transmission.

[0017] Figure 6 It is an axonometric view of a bicycle mid-shaft gearbox clutch assembly using pin gear transmission.

[0018] Figure 7 It is a cross-sectional view of a bicycle mid-shaft transmission clutch assembly that uses pin gear transmission.

[0019] Figure 8 It is a bicycle middle shaft gearbox countershaft clutch core shaft using pin gear transmission.

[0020] Part numbers, part names and descriptions in the attached drawings:

[0021] Figure 2 Middle: Serial number 1 is the crank main shaft assembly of the bicycle middle shaft gearbox with pin gear drive, serial number 2 is the secondary shaft assembly of the bicycle middle shaft gearbox with pin gear drive, serial number 3 is the gearbox housing, serial number 4 is the right end cover of the gearbox, serial number 5 is the connecting bolt, serial number 6 is the bearing, serial number 7 is the secondary shaft locking nut, serial number 8 is the control cable lead-out elbow, serial number 9 is the toothed sprocket of the gearbox power output, serial number 10 is the output sleeve outer bearing, serial number 11 is the power output sleeve of the gearbox, serial number 12 is the output sleeve inner bearing, and serial number 13 is the pin wheel at the left end of the output sleeve. Specific implementation method:

[0022] The power transmission route of the bicycle middle shaft gearbox using pin gear drive is: the crank transmits power to the crank main shaft, the crank main shaft drives a set of cycloid gears to rotate, and a set of pin wheels engaged on the secondary shaft rotate, and a pin wheel is selected by a cable clutch to lock the secondary shaft, and the power is transmitted to the secondary shaft, and the power is returned to the pin wheel on the output sleeve through the cycloid gear on the secondary shaft, thereby driving the chainring sprocket to output power.

[0023] The names, connection methods and functions of the components and parts in the attached drawings are further described in detail:

[0024] Figure 2In: No. 1 is a bicycle middle shaft gearbox crank main shaft assembly using pin gear transmission, which is supported on the gearbox end cover by bearings at both ends of the crank main shaft, and bicycle cranks are installed at both ends of the crank main shaft; No. 2 is a bicycle middle shaft gearbox countershaft assembly using pin gear transmission, and the countershaft is supported on the gearbox end cover by bearings at both ends; No. 3 is the gearbox housing, and the two ends of the housing are connected to the left and right end covers by 6 bolts; No. 4 is the gearbox right end cover; No. 5 is the connecting bolt; No. 6 is the bearing; No. 7 is the countershaft locking nut, which is locked and fixed to the two end covers of the gearbox by nuts at both ends of the countershaft; No. 8 is the control cable lead-out elbow; No. 9 is the gearbox power output chainwheel, which is installed on the power output sleeve through external splines; No. 10 is the output sleeve outer bearing; No. 11 is the gearbox power output The output sleeve is supported on the right end cover of the gearbox through an outer bearing and supports the crank main shaft through an inner bearing. The left end of the output sleeve is connected to a pin wheel through an outer spline, and this pin wheel meshes with the cycloid gear on the secondary shaft to receive the power on the secondary shaft after the speed change. The outer spline on the right end of the output sleeve is connected to the chain wheel sprocket, and the chain wheel sprocket transmits power to the rear hub of the bicycle; No. 12 is the inner bearing of the output sleeve; No. 13 is the pin wheel on the left end of the output sleeve; the power transmission route of the bicycle middle shaft gearbox using pin gear transmission is that the crank transmits power to the crank main shaft, the crank main shaft drives a group of cycloid gears to rotate, and a group of pin wheels meshed with the secondary shaft rotate, and a pin wheel is selected to be locked to the secondary shaft through a cable clutch to transmit power to the secondary shaft, and the power is returned to the pin wheel on the output sleeve through the cycloid gear on the secondary shaft, thereby driving the chain wheel sprocket to output power.

[0025] Figure 3 Middle: Serial number 1001 is the crankshaft, on which a group of 9 cycloid gears are installed through splines to provide 9 speed ratios. There is a spacing sleeve in the middle of the cycloid gear, and the cycloid gear is axially locked by the retaining springs on both sides of the crankshaft; Serial number 1002 is the retaining spring on the left; Serial number 1003 is the cycloid gear; Serial number 1004 is the pin wheel installed on the output sleeve.

[0026] Figure 5In: Serial number 2001 is the countershaft of the pin gear transmission gearbox. The countershaft is a hollow shaft. A set of 9 pin wheels are mounted on the outer circumference of the countershaft. The pin wheels can rotate freely along the outer circumference of the countershaft. Conical radial through holes are arranged axially and circumferentially on the countershaft and correspond to each set of pin wheels. Steel balls are installed in the conical radial through holes. Each pin wheel corresponds to 3 steel balls arranged circumferentially. 27 steel balls are installed on the countershaft. A clutch that can slide axially is installed on the inner circumference of the countershaft. The outer circumference of the clutch can control the lifting of the steel balls to lock a pin wheel and the countershaft; Serial number 2002 is the inner sleeve of the pin wheel. The inner circumference of the inner sleeve of the pin wheel is provided with an axial arc groove to accommodate part of the steel ball. The outer circumference of the inner sleeve of the pin wheel is riveted and locked with the spoke plate of the pin wheel through a spline; Serial number 2003 is the spoke plate of the pin wheel, and a pin wheel has two spoke plates on the left and right; Serial number 2004 is the pin shaft of the pin wheel, and the two ends of the pin shaft are riveted to the spoke plates. The number and distribution of the pin shafts of each pin wheel determine the meshing frequency of the pin wheel, that is, the transmission ratio; Serial number 2005 is the clutch assembly; Serial number 2006 is the cycloid gear connected to the secondary shaft through a spline, which transmits the power on the secondary shaft after the speed change back to the pin wheel on the output sleeve of the main shaft; Serial number 2007 is the fixed shaft of the clutch, which is a hollow shaft installed on the inner circumference of the clutch to guide the axial movement of the clutch and limit the inclination of the clutch. The fixed shaft of the clutch is fastened to the end cover of the transmission through threads at both ends, and a radial through groove of a certain axial length is provided in the middle of the fixed shaft of the clutch (such as Figure 8 ), a sliding key is radially inserted into the through groove; serial number 2008 is a steel ball.

[0027] Figure 7 In the middle; serial number 20051 is the clutch; serial number 20052 is the sliding key retaining spring; serial number 20053 is the sliding key washer; serial number 20054 is the sliding key; serial number 20055 is the sliding key pull rod; the clutch can rotate relative to the sliding key, and the sliding key can move axially but cannot rotate. The control wire is connected to the sliding key pull rod, which pulls the sliding key to move axially, and the sliding key drives the clutch to move axially, and the locked pin wheel is selected to give the transmission ratio.

[0028] The power transmission route of the bicycle middle shaft gearbox using pin gear drive is: the crank transmits power to the crank main shaft, the crank main shaft drives a set of cycloid gears to rotate, and a set of pin wheels engaged on the secondary shaft rotate, and a pin wheel is selected by a cable clutch to lock the secondary shaft, and the power is transmitted to the secondary shaft, and the power is returned to the pin wheel on the output sleeve through the cycloid gear on the secondary shaft, thereby driving the chainring sprocket to output power.

[0029] Speed ​​ratio parameter table of bicycle middle shaft gearbox with pin gear transmission (speed ratio range 298%)

[0030]

[0031] When the bicycle middle shaft gearbox with pin gear drive is in speed stage 1, the clutch is at the rightmost end of the countershaft, and the clutch slides to the left end to increase the speed ratio successively.

Claims

1. Bicycle middle shaft gearbox with pin gear transmission, Its characteristics are: The pin-tooth transmission technology is applied to the bicycle middle shaft gearbox. A group of equidistant cycloid gears with different numbers of teeth are arranged on the crank main shaft. The cycloid gear with a small number of teeth is installed close to the chainring sprocket end. The tooth shape of the cycloid gear is an equidistant cycloid. The gear shape size is the same as that of the bicycle sprocket. The cycloid gear is connected to the crank main shaft to prevent rotation. The crank main shaft is supported on the gearbox end cover through bearings at both ends. The bicycle middle shaft gearbox using pin gear transmission is provided with a group of mutually meshing pin wheels corresponding to the cycloid gear of the crank main shaft on the secondary shaft parallel to the crank main shaft. The pin wheels are riveted assembly structures, and the pin wheels are provided with an inner sleeve. The outer peripheral surface of the inner sleeve of the pin wheel is connected to the pin wheel spoke plate for anti-rotation. The inner peripheral surface of the inner sleeve of the pin wheel is provided with an axial arc groove. The pin wheel is sleeved on the secondary shaft and can be selectively connected to the secondary shaft by a clutch. During operation, only one pin wheel on the secondary shaft can transmit power, and the remaining pin wheels can rotate freely relative to the secondary shaft. A cycloid gear is connected to the right end of the secondary shaft for anti-rotation, which is used to transmit the power on the secondary shaft after speed change back to the pin wheel on the power output sleeve on the main shaft.

2. The bicycle middle shaft gearbox using pin gear transmission according to claim 1, Its characteristics are: The power output sleeve is supported on the right end cover of the gearbox through an outer bearing and supports the crankshaft through an inner bearing. The left end of the power output sleeve is anti-rotatably connected to a pin wheel and meshes with the cycloid gear on the secondary shaft to receive the power after the speed change. The right end of the power output sleeve is anti-rotatably connected to the chainring sprocket.

3. The bicycle middle shaft gearbox using pin gear transmission according to claim 1, Its characteristics are: The secondary shaft parallel to the crankshaft is a hollow shaft, and its two ends are supported on the gearbox end cover by bearings. The secondary shaft is provided with radial conical through holes arranged axially, and steel balls are installed in the radial conical through holes and correspond to the pin wheels. A clutch assembly is installed on the inner circumference of the secondary shaft. The clutch can slide axially relative to the secondary shaft, and the outer circumference of the clutch can control the lifting and lowering of the steel balls to select one of the pin wheels to lock with the secondary shaft and transmit power.

4. The bicycle middle shaft gearbox using pin gear transmission according to claim 3, Its characteristics are: A radial sliding key is arranged on the inner circumference of the clutch, and the clutch can rotate relative to the radial spline. A fixed hollow shaft is installed on the inner circumference of the clutch. Both ends of the fixed shaft are locked to the gearbox end cover by threads. A radial through groove is axially arranged in the middle of the fixed shaft to accommodate the axial movement of the radial sliding key and limit its rotation. There is a through hole in the middle of the radial sliding key to pass the speed change cable. The turning handle rotates the cable to pull the sliding key to move axially, and the sliding key drives the clutch to move axially to realize manual speed change.

5. The bicycle middle shaft gearbox using pin gear transmission according to claim 1, Its characteristics are: Among them The pin wheel is a riveted assembly structure, which is provided with left and right spokes, an inner sleeve and a pin shaft.

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