A bidirectional two-speed transmission device

Abstract

A two-way two-speed variable speed device, belonging to the field of electric vehicles, includes a high-speed gear and a low-speed gear, and an automatic centrifugal device is arranged between them. It includes a spline sleeve, a bowl-shaped centrifugal mechanism and a one-way clutch. The bowl-shaped centrifugal mechanism includes an inner bowl and an outer bowl. The inner periphery of the inner bowl bottom sleeve is provided with an inner spiral spline that meshes with the spline sleeve. The high-speed ratchet teeth are arranged on the inner bowl bottom sleeve, and the low-speed ratchet teeth are arranged on the edge of the inner bowl. Grooves corresponding to the ratchet teeth are respectively arranged on the high-speed gear and the low-speed gear. The outer periphery of the outer bowl bottom sleeve is provided with an annular damping spring with a handle. The inner or outer ring of the one-way clutch is respectively fixed to the edges of the inner bowl and the outer bowl. A plurality of throwing beads are arranged between the bead cover and the inner bowl. An annular array of arc-shaped guiding strips is arranged inside the high-speed gear. This device can reduce the manual operation procedures, increase the operation levels, select the running speed according to the road and load, and automatically switch the driving speed according to the needs.

Description

Technical Field

[0001] The utility model relates to a speed change device, in particular to a bidirectional two-speed speed change device, belonging to the field of electric vehicles. Background Technique

[0002] Since electric vehicles have a large torque in the low-speed operation state and a small torque in the high-speed operation state, during the specific operation process, different operation speeds can be selected according to road conditions or load sizes. For example: when the load is large or climbing a slope, a low-speed operation mode can be selected to obtain a large torque; this is especially true for electric tricycles. On flat roads or under light loads, a high-speed driving mode can be selected to save driving time. Because different speeds can meet the needs of different roads or traction, electric vehicles that could only run on flat roads before have started to run in hilly areas and even on mountain roads, providing a fast means of transportation for residents in remote mountainous areas to get out of the mountains. So far, the switching between different speeds is generally achieved by manually moving the shift fork to change different operation gears. However, for ordinary people, the operation is relatively cumbersome and requires proficiency to drive the electric vehicle flexibly. For the elderly and women, they are often afraid of causing operation errors and unnecessary driving problems such as running wild. They have a certain sense of unfamiliarity with the manual shifting device and even reject it. They do not want to distract their attention to switch gears during driving. However, without switching speeds, they cannot cope with high-load or sloping roads. A problem has been presented to technicians that needs to be overcome.

[0003] In the field of electric vehicle technology, previously, a spiral clutch shifting device with the application number 2020211876585 was applied for. Figure 8 is the overall structural schematic diagram of the spiral clutch shifting device, Figure 9 is the side structural schematic diagram of the shifting gear, Figure 10The utility model is a decomposition diagram of a helical clutch gear-engaging mechanism arranged on a gear-shift shaft. The helical clutch gear-engaging device of the utility model comprises a power tooth 50, a power transmission mechanism is connected to the power tooth 50, and the power transmission mechanism is rotationally connected to a low-speed gear 41. The low-speed gear 41 is circumferentially slidably arranged on a gear-shift shaft 54, and a gear-engaging external spline 51a is arranged on the outer periphery of the gear-shift shaft 54. The side of the low-speed gear 41 is provided with an outer annular array of beveled grooves 44 and a low-speed lever 43. The outer beveled edges 45 of the outer annular array of beveled grooves 44 are all inclined in the circumferential direction. The gear-shift shaft 54 ​​on the side of the low-speed gear 41 is provided with a helical gear. The spiral clutch mechanism 42 is provided with a gear engaging spline sleeve 51, a gear engaging spiral spline sleeve 124, and a gear engaging annular damping spring 121 with a ring handle 121a in sequence from the gear shift shaft 54 ​​to the outer periphery. The gear engaging spiral spline sleeve 124 is provided with a gear engaging ratchet 124a on the side facing the low-speed gear 41. The gear engaging ratchet 124a is arranged opposite to the outer annular array bevel groove 44 and fits with each other. When the low-speed gear 41 rotates, the low-speed lever 43 drives the ring handle 121a to rotate, and the gear shift output tooth 53 is fixedly connected to the gear shift shaft.

[0004] In this embodiment, the power transmission mechanism includes a double-coupled shaft 40, to which a double-coupled tooth 1 40a and a double-coupled tooth 2 40b are fixedly connected, a low-speed gear 41b is meshed with the double-coupled tooth 2 40b, and another gear engaging gear meshing therewith can be provided on the double-coupled tooth 1 40a using the principle of the present invention.

[0005] In addition, the power transmission mechanism can also be symmetrically arranged with the vertical center of the outer periphery of the low-speed gear 41b as the symmetry axis, and a device identical to the above-mentioned spiral clutch mechanism 42 can be symmetrically arranged on the opposite side of the low-speed gear 41b on the shift shaft 54, so that it is close to the other side of the low-speed gear 41b along the shift shaft 54, and the same symmetrical gear shift ratchet 124a is used to implement linkage with the low-speed gear 41b to achieve the purpose of the power transmission mechanism.

[0006] The inner circumference of the gear engaging spline sleeve 51 is the gear engaging inner spline 51b, the outer circumference of the spline sleeve 51 is the outer spiral spline sleeve 127, the gear engaging spiral spline sleeve 124 is meshed with the outer circumference of the spline sleeve 51, the inner circumference of the gear engaging spiral spline sleeve 124 is the inner gear engaging spiral spline 126, and the outer circumference is a smooth structure. The outer circumference of the gear engaging spiral spline sleeve 124 is the gear engaging one-way clutch 56, and an annular damping spring groove is provided on the gear engaging outer ring 122 of the gear engaging one-way clutch 56, in which a gear engaging annular damping spring 121 with a ring handle 121a is provided, 125 is a gear engaging ball, and a gear engaging outer ring gear ring 130 is provided on the outer side of the gear engaging outer ring 122.

[0007] The inclination angle of the shifting ratchet 124a is the same as the inclination angle of the outer hypotenuse 45 of the outer annular array bevel groove 44. The number of the shifting ratchets 124a is the same as the number of the outer annular array bevel grooves 44. The end area of the shifting ratchet 124a is less than or equal to the bottom area of the outer annular array bevel groove 44.

[0008] The locking rotation direction between the shifting outer ring 122 and the shifting inner ring 123 of the shifting one-way clutch 46 is the same as the shifting rotation direction.

[0009] The shifting inner ring 123 is fixedly connected to the outer periphery of the shifting helical spline sleeve 124, so that the shifting inner ring 123 and the shifting helical spline sleeve 124 form an integral structure. In addition, an interference fit can also be used to fit the shifting inner ring 123 and the shifting helical spline sleeve 124 together, similar to the fit between the inner ring of a bearing and a shaft.

[0010] The shifting rotation direction of the shifting helical spline sleeve 124 is the rotation direction towards the low-speed gear 41b. The shifting rotation direction of the shifting helical spline sleeve 124 is the same as the locking rotation direction of the shifting one-way clutch 46 and the shifting rotation direction of the low-speed gear 41b.

[0011] Originally, there was a structure that could only engage the ratchet and the array-type annular groove when reversing to achieve low-speed reverse. By using the spiral clutch shifting device, in the forward rotation condition, the structure that was originally in a sliding state during forward rotation can be locked between the outer ring and the inner ring of the shifting one-way clutch 46 on the outer periphery. That is to say, in the forward rotation state, the shifting helical spline sleeve 124 that would not originally rotate can be rotated, so that the shifting ratchet 124a and the outer annular array bevel groove 44 are engaged with each other, realizing low-speed forward in the forward state. The structure that could only move forward on the high-speed gear side originally has been changed to low-speed forward in the forward direction when the low-speed gear rotates forward. Using this device broadens the driving gears of the electric vehicle.

[0012] How to achieve the switching between multiple gears by changing the motor speed in an automatic condition is a current issue. Summary of the Invention

[0013] In view of the actual situation that some elderly people and women have a certain resistance to the shifting operation, regarding the problem of how to change the motor speed to achieve the switching between multiple gears, the present utility model provides a two-way two-speed variable speed device, the purpose of which is to reduce the manual operation procedures, increase the operation gears, select the running speed according to the road and load, and automatically switch the driving speed according to the needs.

[0014] The technical solution of the present utility model is: a two-way two-speed transmission device, including a spiral clutch mechanism, a driving gear arranged on the motor output shaft, a high-speed gear and a low-speed gear. The high-speed gear and the low-speed gear are rotatably arranged on the shift shaft, and a shift output gear is integrally arranged on the shift shaft. Intermediate gears are arranged between the driving gear and the high-speed gear, and between the driving gear and the low-speed gear. On the inner side end face of the high-speed gear opposite to the low-speed gear, there are circumferentially inclined annular array arc-shaped guiding strips. An automatic centrifugal device is arranged on the shift shaft between the high-speed gear and the low-speed gear. The automatic centrifugal device includes a spline sleeve, a bowl-shaped centrifugal mechanism and a one-way clutch. The spline sleeve shaft is arranged on the shift shaft, and an external spiral spline is arranged on the outer circumference of the spline sleeve. The bowl-shaped centrifugal mechanism includes a pair of inner bowls and outer bowls with bottoms sleeved together. The inner circumference of the bottom sleeve of the inner bowl is provided with an inner spiral spline meshing with the spline sleeve. On the side of the bottom sleeve of the inner bowl facing the high-speed gear, there are high-speed ratchet teeth, and on the axial direction of the edge of the inner bowl, there are low-speed ratchet teeth. On the high-speed gear, there are circumferentially arrayed bevel edge grooves on the high-speed tooth ring, and on the low-speed gear, there are circumferentially arrayed bevel edge grooves on the low-speed tooth ring, and the inclination directions of the bevels are opposite. The positive and reverse meshing between the high-speed gear and the low-speed gear and the high-speed ratchet teeth and the low-speed ratchet teeth 26 realize forward high-speed rotation and reverse low-speed rotation. On the outer circumference of the bottom sleeve of the outer bowl, there is an annular damping spring with a handle, and the radial position where the handle end of the annular damping spring is located is greater than the outer diameter of the annular array arc-shaped guiding strip. On the axial direction of the edges of the inner bowl and the outer bowl, the inner ring or the outer ring of the one-way clutch is respectively fixed. A bead cover is arranged on the inner side of the bowl of the inner bowl, and a plurality of throwing beads are arranged between the bead cover and the inner bowl. The automatic centrifugal device makes the high-speed ratchet teeth and the low-speed ratchet teeth move axially. After moving, they are respectively meshed and connected with the side grooves of the high-speed gear or the side grooves of the low-speed gear. After meshing, they respectively rotate forward or backward. A spiral clutch mechanism is arranged on the shift shaft outside the low-speed gear, and a differential input gear is meshed with the shift output gear;

[0015] Further, annular array bevel edge grooves are respectively arranged on the inner sides of the high-speed gear and the low-speed gear opposite to each other. The annular array bevel edge grooves are matched with the high-speed ratchet teeth and the low-speed ratchet teeth arranged on both sides of the automatic centrifugal device. The inclination directions of the annular array arc-shaped guiding strips arranged on the inner side end face of the high-speed gear are consistent in the circumferential direction. The inclination angles of the high-speed ratchet teeth and the low-speed ratchet teeth are opposite. The high-speed ratchet teeth are meshed with the annular array bevel edge grooves of the high-speed gear during forward rotation, and the low-speed ratchet teeth are meshed with the annular array bevel edge grooves of the low-speed gear during reverse rotation. On the outside of the low-speed gear, there are low-speed shift rods and outer circumferential array bevel edge grooves. The low-speed gear is linked with the spiral clutch mechanism to perform low-speed forward rotation;

[0016] Further, the outer circumference of the shift shaft is a straight external spline, on which a spline sleeve is fitted. The outer circumference of the spline sleeve is an external spiral spline, and the internal spiral spline matching the external spiral spline is arranged on the inner circumference of the bottom sleeve of the inner bowl and is an integral structure with the inner bowl bottom sleeve. The axial length of the internal spiral spline is less than the axial length of the inner bowl bottom sleeve, and there is space for arranging a resilient spring in the inner bowl bottom sleeve. A step is arranged between the space for the resilient spring and the internal spiral internal spline;

[0017] Further, the circumferential spacing between the annular-array arc-shaped guide strips is greater than or equal to the diameter of the handle part of the handle damping spring arranged in the automatic centrifugal device, and the circumferential inclination directions of the annular-array arc-shaped guide strips are the same;

[0018] Further, the annular diameter of the annular-array bevel grooves on the inner side of the high-speed gear is less than the annular diameter of the annular-array bevel grooves on the inner side of the low-speed gear;

[0019] Further, an axial resilient spring is arranged between the high-speed gear and the inner bowl bottom sleeve step in the automatic centrifugal device, and an annular damping spring is arranged on the outer circumference of the outer bowl bottom sleeve. The outer diameter of the annular damping spring is less than the inner diameter of the annular-array arc-shaped guide strips;

[0020] Further, an outer annular-array bevel groove corresponding to the ratchet teeth on the spiral clutch mechanism is arranged on the outer side of the low-speed gear. The spiral clutch mechanism is arranged on the shift shaft on the outer side of the low-speed gear through a spline. The inclination direction of the outer bevel edge of the outer annular-array bevel groove is the same as that of the high-speed tooth groove bevel edge of the annular-array bevel groove on the high-speed gear, both being in the positive rotation engagement direction;

[0021] Further, the diameter of the circle formed by the low-speed ratchet teeth is greater than the diameter of the circle formed by the high-speed ratchet teeth. The circle formed by the low-speed ratchet teeth is fixed axially on the inner side of the inner bowl edge. The diameter of the low-speed ratchet tooth circle is less than the inner diameter of the inner ring of the one-way clutch. The bead cover is arranged on the inner circumference of the low-speed ratchet teeth.

[0022] The positive effects of the present utility model are as follows: By arranging intermediate gears between the driving gear and the high-speed gear, and between the driving gear and the low-speed gear, and the inclined directions of the annular array bevel grooves provided on the high-speed gear and the low-speed gear are opposite, and the high-speed ratchet teeth and the low-speed ratchet teeth are also opposite. Therefore, it can ensure the forward meshing and reverse meshing between the high-speed gear and the low-speed gear and the high-speed ratchet teeth and the low-speed ratchet teeth, realize forward high-speed rotation and reverse low-speed rotation, and thus realize the forward and backward movement of the vehicle; By arranging circumferentially inclined annular array arc guiding strips on the inner end faces of the high-speed gears opposite to the low-speed gears, when rotating in the reverse direction, the annular array arc guiding strips can guide the handles of the annular damping springs arranged on the outer periphery of the outer bowl bottom sleeve to enter the circumferential spacing of the arc guiding strips along their bevel edges and be in a standby state, which is beneficial to the forward rotation of the motor. Driven by the spiral spline in the automatic centrifugal device, the high-speed ratchet teeth enter the annular array bevel grooves arranged on the inner side of the high-speed gear to realize high-speed forward rotation; By arranging an automatic centrifugal device between the high-speed gear and the low-speed gear, the speed change of the motor can be utilized to make the beads in the bowl-shaped centrifugal mechanism move radially under the centrifugal force generated by the speed change. When rotating at high speed in the reverse direction, the beads are thrown towards the bowl edge side of the inner bowl. Since the gap between the bowl cover and the inner bowl is wide at the axis and narrow at the bowl edge side, and the bowl edge side is smaller than the diameter of the beads, the beads will squeeze the inner bowl and the outer bowl towards the high-speed gear side, causing the inner bowl to drive the outer bowl and its bottom sleeve to move axially towards the high-speed gear side, making the outer bowl bottom sleeve and the annular damping springs arranged on its outer periphery rotate circumferentially. At the same time, the handle of the annular damping spring gradually moves along the bevel edge of the annular array arc guiding strip and slides into the circumferential spacing of the arc guiding strip to standby. At this time, since it is a reverse rotation, the high-speed ratchet teeth are not meshed with the high-speed gear and cannot rotate synchronously with the high-speed gear. At the same time, due to the reverse action of the elastic spring, there will be no impact; In this situation, when the motor switches to forward rotation, the automatic centrifugal device moves towards the high-speed gear side driven by the spiral spline. In the forward state, it can also make the high-speed gear and the high-speed ratchet teeth mesh and rotate together. Since the one-way clutch locks between the inner ring and the outer ring during forward rotation, and at the same time the inner bowl is driven by the high-speed ratchet teeth, it drives the spiral spline sleeve, the spline sleeve, the shift shaft and the shift output teeth to rotate synchronously in the locked state, that is, it realizes synchronous forward high-speed rotation.

[0023] On the contrary, when the speed decreases, the beads will roll towards the axis side along the inner bowl. In this case, the task of high-speed switching is completed. When the motor rotates in the reverse direction, the automatic centrifugal device including the spline and the spiral spline, the bowl-shaped centrifugal mechanism and the one-way clutch moves to the low-speed gear side, and the low-speed gear side meshes with the low-speed ratchet teeth to implement low-speed reverse rotation.

[0024] If the spiral clutch mechanism is not provided on the outer side of the low-speed gear, the low-speed gear can only drive the low-speed ratchet to implement the reverse low-speed rotation when rotating in the reverse direction, and cannot realize the forward low-speed rotation. As described in the background technology, after the spiral clutch mechanism is provided, the low-speed ratchet is close to one side of the low-speed gear. As long as the motor rotates in the forward direction, the low-speed lever on the outer side of the low-speed gear drives the outer gear ring of the gear-engaging one-way clutch provided by the spiral clutch mechanism to realize the locking of the gear-engaging one-way clutch, so that the low-speed gear is driven by the gear-engaging ratchet and the gear-engaging one-way clutch to drive the spiral flower spaces and splines inside the spiral clutch mechanism to transmit power to the shift shaft, and the power is output from the shift output gear to realize the low-speed rotation under the forward rotation condition.

[0025] From the above content, it can be seen that low-speed and high-speed rotation can be achieved in forward rotation, and unidirectional rotation can be achieved in reverse rotation. In the process of switching between high speed and low speed, the bowl-shaped centrifugal mechanism can be used to achieve automatic switching between high and low speeds. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The overall structure of the utility model is schematically shown Figure 1 .

[0027] Figure 2 The overall structure of the utility model is schematically shown Figure 2 .

[0028] Figure 3 Cross section of the bowl-shaped centrifuge mechanism in an automatic centrifuge Figure 1 .

[0029] Figure 4 Cross section of the bowl-shaped centrifuge mechanism in an automatic centrifuge Figure 2 .

[0030] Figure 5 Schematic cross-section of an automated centrifuge.

[0031] Figure 6 Exploded view of the automated centrifuge.

[0032] Figure 7 Schematic diagram of the one-way clutch structure between the inner bowl and the outer bowl.

[0033] Figure 8 Schematic diagram of the overall structure of the helical clutch shifting device.

[0034] Figure 9 Schematic diagram of the outer structure of the gear shifting gear.

[0035] Figure 10 Exploded view of the helical clutch mechanism on the gearshift shaft.

[0036] Description of reference numerals: annular array arc guide bar 11, spacing 11a, annular damping spring 12, handle 12a, elastic spring 13, outer bowl 14, outer ring 15, external thread spline 16, inner bowl 17, inner ring 18, bead cover 19, centrifugal beads 20, hypotenuse groove of low-speed gear annular array 21, hypotenuse of low-speed gear groove 22, hypotenuse groove of high-speed gear annular array 23, hypotenuse of high-speed gear groove 24, high-speed ratchet 25, low-speed ratchet 26, external spline 27, step 28, notch 29, clutch beads 30, clutch spring 31, outer bowl bottom sleeve 32, inner and outer bottom sleeves 33, double-shaft 40, double-shaft input gear 40a, double-shaft output gear 40b, high-speed gear 41a, low-speed gear 41b, spiral clutch mechanism 42, low-speed lever 43, outer annular array hypotenuse groove 44, outer hypotenuse 45, transition shaft 47, transition gear 48, power gear 50, gear shift spline sleeve 51, external gear shift spline 51a, internal gear shift spline 51b, shift output gear 53, shift shaft 54, differential input gear 55, gear shift annular damping spring 121, ring handle 121a, gear shift outer ring 122, gear shift inner ring 123, gear shift spiral spline sleeve 124, gear shift ratchet 124a, gear shift ball 125, internal gear shift spiral spline 126, external gear shift spiral spline 127, gear shift outer ring retaining ring 130 Detailed implementation mode

[0037] The technical solution of the present invention will be described in detail with reference to the accompanying drawings. In this description, the forward direction can be understood as the forward movement direction, and the reverse direction can be understood as the reverse movement direction. The forward direction can switch between two speeds (high speed and low speed) for forward movement, and the reverse direction only has one low speed. The high speed is powered by the high-speed gear side, and the low speed is powered by the low-speed gear side.

[0038] The technical solution of the present invention is a two-way two-speed transmission device Figure 1 is the overall structure schematic diagram of the present invention Figure 1 、 Figure 2 is the overall structure schematic diagram of the present invention Figure 2 、 Figure 3 is the cross-section of the bowl-shaped centrifugal mechanism in the automatic centrifugal device Figure 1 、 Figure 4 is the cross-section of the bowl-shaped centrifugal mechanism in the automatic centrifugal device Figure 2。The bidirectional two-speed transmission device includes a spiral clutch mechanism 42, a driving gear 50 arranged on the motor output shaft, a high-speed gear 41a and a low-speed gear 41b. The high-speed gear 41a and the low-speed gear 41b are rotatably arranged on a gear shift shaft 54. A gear shift output gear 53 is integrally arranged on the gear shift shaft 54. Intermediate gears are arranged between the driving gear 50 and the high-speed gear 41a, and between the driving gear 50 and the low-speed gear 41b. On the inner end face of the high-speed gear 41a opposite to the low-speed gear 41b, there are circumferentially inclined annular array arc-shaped guiding strips 11. An automatic centrifugal device is arranged on the gear shift shaft 54 between the high-speed gear 41a and the low-speed gear 41b. The automatic centrifugal device includes a flower-shaped sleeve, a bowl-shaped centrifugal mechanism and a one-way clutch. The bowl-shaped centrifugal mechanism includes a pair of inner bowls 17 and outer bowls 14 with bottom sleeves stacked together. The inner circumference of the inner bowl bottom sleeve 33 is provided with an internal spiral spline. The inner bowl bottom sleeve 33 is provided with high-speed ratchet teeth 25 on the side facing the high-speed gear 41a. The axial direction of the rim of the inner bowl 17 facing the low-speed gear 41b is provided with low-speed ratchet teeth 26. Corresponding grooves are respectively arranged on the high-speed gear 41a and the low-speed gear 41b. The outer circumference of the outer bowl bottom sleeve 32 is provided with an annular damping spring 12 with a handle. The radial position where the handle end of the annular damping spring 12 is located is greater than the outer diameter of the annular array arc-shaped guiding strips 11. On the axial direction of the rims of the inner bowl 17 and the outer bowl 14 facing the low-speed gear 41b side, the inner ring 18 or the outer ring 15 of the one-way clutch is respectively fixed. A bead cover 19 is arranged on the inner side of the bowl of the inner bowl 17. A plurality of throwing beads 20 are arranged between the bead cover 19 and the inner bowl 17. The automatic centrifugal device moves the high-speed ratchet teeth 25 and the low-speed ratchet teeth 26 axially. After moving, they are respectively meshed and connected with the side groove of the high-speed gear 41a or the groove of the low-speed gear 41b. After meshing, they rotate forward or backward respectively. A spiral clutch mechanism 42 is arranged on the gear shift shaft outside the low-speed gear 41b. A differential input gear 55 is meshed with the gear shift output gear 53.

[0039] In this embodiment, a transition gear 48 is meshed with the driving gear 50. The transition gear 48 is fixedly connected to a transition shaft 47. The transition gear 48 simultaneously meshes and transmits power to the high-speed gear 41a and a double-connected input gear 40a fixed on a double-connected shaft 40. A double-connected output gear 40b is fixedly connected to the double-connected shaft 40 at the same time. The double-connected output gear 40b is meshed with the low-speed gear 41b. Through this structure, the number of gears for transmitting power from the driving gear 50 to the low-speed gear 41b is one more than the number of gears for the driving gear 50 to transmit power to the high-speed gear 41a. Eventually, the rotation directions of the high-speed gear 41a and the low-speed gear 41b under the action of power are opposite, and it can achieve fast rotation in the forward direction and slow rotation in the reverse direction. In practical applications, the forward rotation is defined as the forward direction of the vehicle, and the reverse direction is defined as the reverse direction of the vehicle.

[0040] The high-speed gear 41a and the low-speed gear 41b need to transmit power to the shift shaft 54, and finally to the shift output gear 53, and then to the differential. The half shafts at both ends of the differential drive the wheels to rotate.

[0041] The rotation of the wheels at different speeds is achieved through an automatically centrifugal device arranged in the middle from the high-speed gear 41a or the low-speed gear 41b.

[0042] Figure 5 It is a sectional schematic diagram of the automatically centrifugal device. The one-way clutch includes an outer ring 15 connected to the side of the outer bowl 14 facing the low-speed gear 41b and an inner ring 18 connected to the side of the inner bowl 17 facing the low-speed gear 41b. A plurality of triangular notches 29 are provided on the inner ring 18. Clutch beads 30 are arranged in the notches 29, and a clutch spring 31 is arranged behind the clutch beads. When the one-way clutch rotates forward, the inner ring 18 and the outer ring 15 are in a locked state, and the inner ring 18 and the outer ring 15 rotate simultaneously. When rotating in the reverse direction, the inner ring 18 and the outer ring 15 are in a free state, and there is no linkage between the inner ring 18 and the outer ring 15.

[0043] On the inner sides of the high-speed gear 41a and the low-speed gear 41b facing each other, there are respectively provided with a high-speed tooth annular array bevel groove 23 and a low-speed tooth annular array bevel groove 21. The high-speed tooth annular array bevel groove 23, the low-speed tooth annular array bevel groove 21, and the high-speed ratchet teeth 25 and low-speed ratchet teeth 26 provided on both sides of the automatically centrifugal device are engaged. The inclination directions of a plurality of annular array arc guide bars 11 provided on the inner end face of the high-speed gear 41a are consistent in the circumferential direction. The inclination angles of the high-speed ratchet teeth 25 and the low-speed ratchet teeth 26 are opposite. The high-speed ratchet teeth 25 are engaged with the high-speed tooth annular array bevel groove 23 when rotating forward, and the outer inclination angle of the high-speed ratchet teeth 25 is the same as the angle of the high-speed tooth groove bevel 24. The low-speed ratchet teeth 26 are engaged with the low-speed gear annular array bevel groove 21 when rotating in the reverse direction, and the outer inclination angle of the low-speed ratchet teeth 26 is the same as the angle of the high-speed tooth groove bevel 22. A low-speed shift lever 43 and an outer annular array bevel groove 44 are provided on the outer side of the low-speed gear 41b. The low-speed gear 41b is linked with the spiral clutch mechanism 42 through the low-speed shift lever 43 and the outer annular array bevel groove 44, and can achieve low-speed forward rotation.

[0044] Figure 6 It is an exploded schematic diagram of the automatically centrifugal device. The shift shaft 54 is provided with a spline sleeve on the outer spline provided on its outer circumference. The inner circumference of the spline sleeve is a straight inner spline, and its outer circumference is provided with an inner spiral spline through the outer spiral spline 16 provided on its outer circumference. The inner spiral spline is integrally arranged on the inner circumference of the inner bowl bottom sleeve 33. The axial length of the spiral inner spline is less than the axial length of the inner bowl bottom sleeve 33. A step 28 is provided between the inner bowl bottom sleeve 33 and the spiral inner spline. One end of a spring 13 is provided on the step 28 of the inner bowl bottom sleeve 33, and the other end of the spring 13 contacts the high-speed gear axially.

[0045] The circumferential spacing 11a between the annular array of arc-shaped guiding bars 11 is greater than or equal to the diameter of the handle portion 12a of the handle damping spring provided in the automatic centrifugal device, and the inclination directions of the multiple annular array of arc-shaped guiding bars 11 in the circumferential direction are the same.

[0046] The annular diameter of the high-speed tooth annular array bevel groove 23 inside the high-speed gear 41a is smaller than the annular diameter of the low-speed tooth annular array bevel groove 21 inside the low-speed gear 41b.

[0047] An axial elastic spring 13 is provided between the high-speed gear 41a and the inner step 28 of the bowl bottom sleeve 33 in the automatic centrifugal device. An annular damping spring 12 is provided on the outer circumference of the outer bowl bottom sleeve 32, and the outer diameter of the annular damping spring 12 is smaller than the inner diameter of the annular array of arc-shaped guiding bars 11.

[0048] On the outside of the low-speed gear 41b, there is an outer annular array bevel groove 44 corresponding to the ratchet teeth on the spiral clutch mechanism. The spiral clutch mechanism 42 is arranged on the shift shaft 54 outside the low-speed gear 41b through a spline. The inclination direction of the outer bevel 45 of the outer annular array bevel groove 44 is the same as the inclination direction of the high-speed tooth groove bevel 24 of the high-speed tooth annular array bevel groove 23 on the high-speed gear 41a, and they can be engaged during forward rotation.

[0049] In the above automatic centrifugal device, a straight external spline 27 is provided on the shift shaft 54. A spline sleeve is provided on the straight external spline 27. The inner circumference of the spline sleeve is a straight internal spline, and the outer circumference of the spline sleeve is machined with an external spiral spline 16. The external spiral spline 16 meshes with the internal spiral spline provided on the inner circumference of the inner bowl bottom sleeve 33. The internal spiral spline and the inner bowl bottom sleeve 33 are of an integral structure, but a part of the inner bowl bottom sleeve 33 is the internal spiral spline, and another part is for the space for setting one end of the elastic spring 13. A step 28 is provided between the space of the elastic spring 13 and the internal spiral spline, and the inner diameter of the space is larger than the inner diameter of the internal spiral spline.

[0050] The diameter of the ring formed by the low-speed ratchet teeth 26 is larger than the diameter of the ring formed by the high-speed ratchet teeth 25. The ring formed by the low-speed ratchet teeth 26 is fixed axially on the inner side of the edge of the inner bowl 17 facing the low-speed gear 41b. The diameter of the ring formed by the low-speed ratchet teeth 26 is smaller than the diameter of the inner ring 18 of the one-way clutch. The bead cover 19 is arranged on the inner circumference of the low-speed ratchet teeth 26, and the annular diameter formed by the low-speed ratchet teeth 26 is smaller than the diameter of the inner ring 18.

[0051] In the present utility model, an intermediate gear is provided between the driving gear 50 and the high-speed gear 41a, and between the driving gear 50 and the low-speed gear 41b. Moreover, the inclined directions of the hypotenuse of the annular array of bevel grooves 23 on the high-speed gear 41a and the hypotenuse of the annular array of bevel grooves 21 on the low-speed gear 41b are opposite, and the high-speed ratchet teeth 25 and the low-speed ratchet teeth 26 are also opposite. Therefore, it can ensure the forward and reverse meshing between the high-speed gear 41a and the low-speed gear 41b and the high-speed ratchet teeth 25 and the low-speed ratchet teeth 26, realize forward high-speed rotation and reverse low-speed rotation, and thus realize the forward and backward movement of the vehicle; by providing a circumferentially inclined annular array of arc-shaped guiding strips 11 on the inner end face of the high-speed gear 41a opposite to the low-speed gear 41b, when rotating in the reverse direction, the annular array of arc-shaped guiding strips 11 can guide the handle 12a of the annular damping spring 12 provided on the outer periphery of the outer bowl bottom sleeve 32 to enter the circumferential pitch 11a of the arc-shaped guiding strip along its hypotenuse and be in a standby state, which is beneficial for the speed change device to enter the annular array of bevel grooves provided on the inner side of the high-speed gear 41a through the spiral spline in the automatic centrifugal device when rotating in the forward direction, so as to realize high-speed forward rotation; by providing an automatic centrifugal device between the high-speed gear 41a and the low-speed gear 41b, the speed change of the motor can be utilized to make the ball 20 in the bowl-shaped centrifugal mechanism move radially along with the centrifugal force generated by the speed change. When rotating at high speed in the reverse direction, the ball 20 is thrown towards the bowl edge side of the inner bowl 17. Since the gap between the bowl cover and the inner bowl 17 is wide at the axis center and narrow at the bowl edge side, and the gap at the bowl edge side is smaller than the diameter of the ball 20, the ball 20 will squeeze the inner bowl 17 and the outer bowl 14 towards the high-speed gear 41a side, making the inner bowl 17 drive the outer bowl 14 and its bottom sleeve to axially move towards the high-speed gear 41a side, so that the outer bowl bottom sleeve 32 and the annular damping spring 12 provided on its outer periphery rotate circumferentially along the spiral spline. At the same time, the handle 12a of the annular damping spring 12 gradually moves along the hypotenuse of the annular array of arc-shaped guiding strips 11 and slides into the circumferential pitch 11a of the arc-shaped guiding strip during rotation and is in standby. Due to the provision of the compression elastic spring 13, the movement will not cause impact. At this time, since it is rotating in the reverse direction, the high-speed ratchet teeth 25 are not meshed with the high-speed gear 41a and cannot rotate synchronously with the high-speed gear 41a; in this situation, when the motor switches to forward rotation, the automatic centrifugal device is driven by the spiral spline and moves towards the high-speed gear 41a side. In the forward state, it can also make the high-speed gear 41a and the high-speed ratchet teeth 25 mesh and rotate together. Since the inner ring 18 and the outer ring 15 of the one-way clutch are locked during forward rotation, the inner bowl 17 is driven by the high-speed ratchet teeth 25 and drives the spiral spline sleeve, the spline sleeve, the shift shaft 54 and the shift output gear 53 to rotate synchronously in the locked state, that is, synchronous forward high-speed rotation is realized.

[0052] On the contrary, when the speed is reduced, the bead 20 will roll along the inner bowl 17 to the side of the axis, in which case the high-speed switching task is completed. When the motor rotates in the reverse direction, the automatic centrifugal device including the bowl-shaped centrifugal mechanism and the one-way clutch is moved to the side of the low-speed gear 41b by using the spline and spiral spline, and the low-speed tooth annular array bevel groove 21 set on the side of the low-speed gear 41b is meshed with the low-speed ratchet 26 to implement low-speed reverse rotation.

[0053] If the spiral clutch mechanism 42 is not provided on the outside of the low-speed gear 41b, the low-speed gear 41b can only drive the low-speed ratchet 26 to implement reverse low-speed rotation when rotating in the reverse direction, and cannot achieve forward low-speed rotation. As described in the background technology, after the spiral clutch mechanism 42 is provided, the low-speed ratchet 26 is close to one side of the low-speed gear 41b. As long as the motor rotates in the forward direction, the low-speed lever 43 on the outside of the low-speed gear 41b drives the gear-engaging outer ring 15 of the gear-engaging one-way clutch provided on the spiral clutch mechanism 42 to achieve the locking of the gear-engaging one-way clutch, so that the low-speed gear 41b is driven by the gear-engaging ratchet and the gear-engaging one-way clutch to drive the gear-engaging spiral splines and splines inside the spiral clutch mechanism 42 to transmit power to the shift shaft 54, and the power is output from the shift output gear 53 to achieve low-speed rotation under the forward rotation condition.

[0054] From the above content, it can be seen that low-speed and high-speed rotation can be achieved in forward rotation, and unidirectional rotation can be achieved in reverse rotation. In the process of switching between high speed and low speed, the bowl-shaped centrifugal mechanism can be used to achieve automatic switching between high and low speeds.

[0055] Although a swinging ball is used in the automatic centrifugal device described in this embodiment, according to this principle, a swinging block or other similar components can also be used to achieve the above-mentioned actions, ultimately achieving the linkage between the high-speed ratchet and the high-speed gear, and the linkage between the low-speed ratchet and the low-speed gear.

Claims

1. A two-way two-speed variable speed device, comprising a spiral clutch mechanism, a driving gear arranged on the motor output shaft, a high-speed gear and a low-speed gear. The high-speed gear and the low-speed gear are rotatably arranged on the shift shaft, and a shift output gear is integrally arranged on the shift shaft. Characterized in that: An intermediate gear is arranged between the driving gear and the high-speed gear, and between the driving gear and the low-speed gear. On the inner side end face of the high-speed gear opposite to the low-speed gear, there are circumferentially inclined annular array arc-shaped guiding strips. An automatic centrifugal device is arranged on the shift shaft between the high-speed gear and the low-speed gear. The automatic centrifugal device includes a spline sleeve, a bowl-shaped centrifugal mechanism and a one-way clutch. The spline sleeve shaft is arranged on the shift shaft, and an external spiral spline is arranged on the outer periphery of the spline sleeve. The bowl-shaped centrifugal mechanism includes a pair of inner bowl and outer bowl with bottom sleeves stacked together. The inner periphery of the bottom sleeve of the inner bowl is provided with an inner spiral spline meshing with the spline sleeve. On the side of the bottom sleeve of the inner bowl facing the high-speed gear, there are high-speed ratchet teeth. On the axial direction of the edge of the inner bowl, there are low-speed ratchet teeth. On the high-speed gear, there are high-speed tooth annular array beveled edge grooves, and on the low-speed gear, there are low-speed tooth annular array beveled edge grooves, and the inclination directions of the beveled edges are opposite. The forward and reverse meshing between the high-speed gear and the low-speed gear and the high-speed ratchet teeth and the low-speed ratchet teeth realize forward high-speed rotation and reverse low-speed rotation. On the outer periphery of the bottom sleeve of the outer bowl, there is an annular damping spring with a handle. The radial position where the handle end of the annular damping spring is located is greater than the outer diameter of the annular array arc-shaped guiding strip. On the axial direction of the edges of the inner bowl and the outer bowl, the inner ring or outer ring of the one-way clutch is respectively fixed. A bead cover is arranged on the inner side of the bowl of the inner bowl. A plurality of throwing beads are arranged between the bead cover and the inner bowl. The automatic centrifugal device makes the high-speed ratchet teeth and the low-speed ratchet teeth move axially. After moving, they are respectively meshed and connected with the side grooves of the high-speed gear or the side grooves of the low-speed gear. After meshing, they rotate forward or backward respectively. A spiral clutch mechanism is arranged on the shift shaft outside the low-speed gear, and a differential input gear is meshed with the shift output gear.

2. A two-way two-speed variable speed device according to claim 1, Characterized in that: Circumferentially inclined annular array beveled edge grooves are respectively arranged on the inner sides of the high-speed gear and the low-speed gear opposite to each other. The annular array beveled edge grooves are matched with the high-speed ratchet teeth and the low-speed ratchet teeth arranged on both sides of the automatic centrifugal device. The inclination directions of the annular array arc-shaped guiding strips arranged on the inner side end face of the high-speed gear are consistent in the circumferential direction. The inclination angles of the high-speed ratchet teeth and the low-speed ratchet teeth are opposite. The high-speed ratchet teeth are meshed with the annular array beveled edge grooves of the high-speed gear during forward rotation, and the low-speed ratchet teeth are meshed with the annular array beveled edge grooves of the low-speed gear during reverse rotation. A low-speed shift lever and an outer circumferential annular array beveled edge groove are arranged outside the low-speed gear. The low-speed gear is linked with the spiral clutch mechanism to perform low-speed forward rotation.

3. A two-way two-speed variable speed device according to claim 1, Characterized in that: The outer periphery of the shift shaft is a straight external spline, on which a spline sleeve is fitted. The outer periphery of the spline sleeve is an external spiral spline, and the internal spiral spline matching the external spiral spline is arranged on the inner periphery of the inner bowl bottom sleeve and is an integral structure with the inner bowl bottom sleeve. The axial length of the internal spiral spline is less than the axial length of the inner bowl bottom sleeve, and there is space for arranging a resilient spring in the inner bowl bottom sleeve. A step is arranged between the space for the resilient spring and the internal spiral internal spline.

4. A two-way two-speed transmission device according to claim 1, characterized in that: The circumferential spacing between the annular array of arc-shaped guide strips is greater than or equal to the diameter of the handle part of the handle damping spring arranged in the automatic centrifugal device, and the circumferential inclination directions of the annular array of arc-shaped guide strips are the same.

5. A two-way two-speed transmission device according to claim 1, characterized in that: The annular diameter of the annular array of bevel grooves on the inner side of the high-speed gear is smaller than the annular diameter of the annular array of bevel grooves on the inner side of the low-speed gear.

6. A two-way two-speed transmission device according to claim 1, characterized in that: An axial resilient spring is arranged between the high-speed gear and the inner step of the inner bowl bottom sleeve of the automatic centrifugal device, and an annular damping spring is arranged on the outer periphery of the outer bowl bottom sleeve. The outer diameter of the annular damping spring is smaller than the inner diameter of the annular array of arc-shaped guide strips.

7. A two-way two-speed transmission device according to claim 1, characterized in that: An outer annular array of bevel grooves corresponding to the ratchet teeth on the spiral clutch mechanism is arranged on the outer side of the low-speed gear. The spiral clutch mechanism is arranged on the shift shaft on the outer side of the low-speed gear through splines. The inclination direction of the outer bevel edge of the outer annular array of bevel grooves is the same as the inclination direction of the high-speed tooth groove bevel edge of the annular array of bevel grooves on the high-speed gear, both being for forward rotation engagement.

8. A two-way two-speed transmission device according to claim 1, characterized in that: The diameter of the circle formed by the low-speed ratchet teeth is larger than the diameter of the circle formed by the high-speed ratchet teeth. The circle formed by the low-speed ratchet teeth is fixed axially on the inner side of the inner bowl edge. The diameter of the circle formed by the low-speed ratchet teeth is smaller than the inner diameter of the one-way clutch, and a bead cover is arranged on the inner circumference of the low-speed ratchet teeth.

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