Gear shifting mechanism and gearbox

Abstract

The utility model discloses a gear shifting mechanism and a gearbox, the gear shifting mechanism comprises a main shaft and an auxiliary shaft which are arranged in parallel, and a plurality of driven gears are fixed on the auxiliary shaft; the main shaft is sleeved with a driving gear corresponding to the driven gear in a relatively rotating mode. A core shaft capable of axially moving is arranged in the main shaft and comprises a core rod and an annular boss on the core rod, and guide surfaces are arranged on two sides of the boss; limiting holes communicated with the core hole are formed in the main shaft, correspond to the driving gears one to one and are evenly distributed in the circumferential direction of the main shaft. A plurality of limiting grooves are formed in the inner ring of the driving gear, and the number of the grooves is N times that of the limiting holes; a locking block capable of moving in the radial direction is arranged in the limiting hole, and when the mandrel moves, the locking block slides to the boss so that the locking block can penetrate out of the main shaft and be matched with the limiting groove. The gear shifting mechanism and the gearbox are reasonable in structure, and multi-gear switching can be achieved in a small space.

Description

Technical Field

[0001] The utility model relates to the field of gear shifting and speed change, in particular to a gear shifting mechanism and a gearbox. Background Art

[0002] The gearbox is a mechanism used to change the speed and torque from the engine. The gearbox mainly applies the speed reduction principle of gear transmission. Simply put, there are multiple sets of gear pairs with different transmission ratios in the gearbox, and the gear shifting behavior when the car is driving is to make different gear pairs in the gearbox work through the operating mechanism. For example, at low speed, the gear pair with a large transmission ratio is allowed to work, and at high speed, the gear pair with a small transmission ratio is allowed to work. The existing shifting structure mainly uses a shift fork to shift the synchronizer gear ring to achieve the engagement and separation of each forward gear; each synchronizer gear ring can only engage or separate two gears. Once the number of gears increases, the number of synchronizer gear rings needs to be increased, which will not only increase the structural complexity of the shifting mechanism, but also increase the size of the gearbox. Utility Model Content

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: how to provide a shift mechanism and a gearbox with a reasonable structural design and capable of achieving multiple gear switching in a relatively small space.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] A shift mechanism, characterized in that it comprises a main shaft and a secondary shaft arranged in parallel, a plurality of driven gears are fixedly arranged side by side on the secondary shaft; a driving gear is relatively rotatably sleeved on the main shaft and is correspondingly meshed with the driven gears; the main shaft has a coaxially arranged core hole, a core shaft is axially movably fitted in the core hole, the core shaft comprises a core rod and an annular boss radially protruding from the core rod, both sides of the annular boss have guide surfaces with gradually decreasing diameters; the main shaft has a core hole radially oriented with the driven gears, A limiting hole is set through the core hole, the limiting holes are set one by one corresponding to the driving gears, and at least one limiting hole is evenly distributed along the circumference of the main shaft; the inner ring of the driving gear has a plurality of evenly distributed limiting grooves, the number of the limiting grooves is N times the number of the limiting holes, and N is a natural number; a locking block that can move radially along the main shaft is set in the limiting hole, and the locking block can slide along the guide surface to the annular boss during the axial movement of the core shaft, so that the locking block passes through the main shaft and fits in the limiting groove.

[0006] With the above structure, a plurality of limiting holes are provided on the main shaft, and limiting grooves are evenly arranged on the inner ring of the driving gear rotatably sleeved on the main shaft corresponding to the number of the limiting holes. When the shaft core is placed in the core hole of the main shaft, the boss fixed on the shaft core can abut against the bottom below the corresponding gear locking block when the shaft core is moved, so that the locking block protrudes from the surface of the main shaft and engages with the limiting groove. In this way, when the main shaft rotates, it can drive the driving gear of the corresponding gear to rotate, thereby realizing gear shifting. Since the shifting mechanism mainly uses the main shaft and the countershaft, the clearance space between the driving gears needs to be small, and the required length of the shaft is reduced, reducing the overall volume of the transmission.

[0007] Further, the locking block is a ball arranged in the limiting hole, the diameter of the ball is smaller than the diameter of the limiting hole, and the ball is in clearance fit in the limiting hole.

[0008] In this way, when the core shaft moves axially, the ball rolls relative to the surface of the core shaft in the limiting hole, so that it can better roll along the guiding surface of the core shaft onto the annular boss, making the gear shifting operation smoother.

[0009] Further, the limiting groove is arc-shaped and runs through along the axial direction of the driving gear; the width of the limiting groove matches the diameter of the limiting hole.

[0010] Further, one end of the core hole penetrates through the main shaft and is provided with a limiting sleeve, and the other end has a guiding hole arranged coaxially. The inner diameters of the limiting sleeve and the guiding hole both match the diameter of the core rod, and both ends of the core rod can axially slide and fit in the limiting sleeve and the guiding hole.

[0011] In this way, when both ends of the core rod pass through the limiting sleeve and the guiding hole with the same inner diameter, the shaft core can slide radially in the core hole of the main shaft, and the core rod will not break away from the main shaft.

[0012] Further, a positioning seat is arranged on the main shaft, the positioning seat has a positioning hole arranged radially along the main shaft, the positioning hole penetrates through the main shaft and communicates with the guiding hole; an annular groove is formed on the core rod extending circumferentially, a positioning bead for cooperating with the annular groove is arranged in the positioning hole, and a spring is arranged in the positioning hole and abuts against the positioning bead in a compressed manner to make the positioning bead abut against the core rod; the annular grooves are arranged corresponding to the driving gears one by one in the axial direction of the core rod, and the distance between any annular groove and the corresponding driving gear is equal.

[0013] In this way, when the gear is shifted, the core pulling is pulled and moved away. The ball in the annular groove against which the spring abuts will temporarily return to the cavity due to the force extrusion, and due to the elastic potential energy, the ball will re-abut against the annular groove corresponding to the current gear. This can not only lock the current gear to prevent accidental gear shifting, but also enable the user to determine the currently shifted gear through the force feedback, making the gear shifting operation smoother.

[0014] Further, the main shaft is provided with a threaded hole penetrating through in the radial direction and communicating with the guiding hole. The positioning seat is cylindrical, and one end has an external thread and is connected to the threaded hole. The positioning hole is coaxially and penetratingly arranged on the positioning seat, and a threaded plug is fitted at the end of the positioning hole facing away from the main shaft. The two ends of the spring respectively abut against the positioning ball and the threaded plug.

[0015] Further, two positioning seats are symmetrically arranged along the radial direction of the main shaft.

[0016] A gearbox includes a box body, and the gear shifting mechanism as described above is arranged inside the box body.

[0017] Further, one end of the main shaft is coaxially connected with a clutch, and the other end is rotatably supported inside the box body through a bearing. A rotatable shift fork shaft penetrates through the box body. The shift fork shaft is orthogonally arranged with the main shaft, and a shift fork is arranged at the inner end. One end of the core shaft facing away from the clutch penetrates out of the main shaft and is provided with a shift fork disc. An annular shift fork groove is formed by circumferentially extending on the shift fork disc, and the shift fork is fitted in the shift fork groove.

[0018] Further, the outer end of the shift fork shaft has a shift fork connecting rod extending in the radial direction. The box body is provided with a gear position plate corresponding to the shift fork connecting rod. The gear position plate is provided with an arc-shaped gear position groove. A sliding sleeve that can move along the gear position groove penetrates through the gear position groove, and the sliding sleeve is connected to the shift fork connecting rod. The end of the shift fork connecting rod is extendedly connected with a shift lever.

[0019] In summary, both the gear shifting mechanism and the gearbox of the present utility model have the advantages of reasonable structural design and being able to achieve multiple gear shifts in a relatively small space. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the overall structure of the gear shifting mechanism in this embodiment.

[0021] Figure 2 It is a schematic cross-sectional structure diagram of this embodiment.

[0022] Figure 3 and Figure 4 It is a schematic diagram of the cooperation relationship structure between the main shaft and the countershaft.

[0023] Figure 5 Schematic cross-sectional structure diagram of the main shaft.

[0024] Figure 6 Schematic structure diagram of the main shaft.

[0025] Figure 7 Schematic structure diagram of the mandrel.

[0026] Figure 8 Schematic structure diagram of the driving gear. Specific implementation mode

[0027] The present utility model will be further described in detail below in conjunction with embodiments.

[0028] During specific implementation: As Figures 1 to 8 shown, a gearbox includes a housing 8 and a shifting mechanism disposed within the housing 8. The shifting mechanism includes a main shaft 1 and a countershaft 2 arranged in parallel. A plurality of driven gears 3 are fixedly arranged side by side on the countershaft 2. A driving gear 4 corresponding to and meshing with the driven gears 3 is rotatably sleeved on the main shaft 1. A core hole 11 is coaxially arranged on the main shaft 1. A mandrel 5 is axially movably fitted within the core hole 11. The mandrel 5 includes a core rod 51 and an annular boss 52 radially protruding from the core rod 51. Both sides of the annular boss 52 have guiding surfaces 53 with gradually decreasing diameters. The main shaft 1 has a limiting hole 12 radially communicating with the core hole 11. The limiting holes 12 are arranged corresponding to the driving gears 4 one by one and are evenly distributed circumferentially around the main shaft 1 with at least 2. The inner ring of the driving gear 4 has a plurality of evenly distributed limiting grooves 41. The number of the limiting grooves 41 is N times that of the limiting holes 12, where N is a natural number. In this embodiment, the number of the limiting holes 12 corresponding to each driving gear 4 is 3, and the number of the limiting grooves 41 inside the driving gear 4 is 6, that is, N is 2. A locking block 6 that can move radially along the main shaft 1 is arranged in the limiting hole 12. The locking block 6 can slide along the guiding surface 53 onto the annular boss 52 during the axial movement of the mandrel 5, so that the locking block 6 penetrates through the main shaft 1 and is fitted in the limiting groove 41.

[0029] As Figure 2 and Figure 5 shown, the locking block 6 is a ball arranged in the limiting hole 12. The diameter of the ball is smaller than the diameter of the limiting hole 12 and is in clearance fit with the limiting hole 12. As Figure 8 shown, the limiting groove 41 is arc-shaped and axially penetrates through the driving gear 4; the width of the limiting groove 41 matches the diameter of the limiting hole 12.

[0030] One end of the core hole 11 penetrates through the main shaft 1 and is provided with a limit sleeve 13, and the other end has a guiding hole 14 arranged coaxially. The inner diameters of the limit sleeve 13 and the guiding hole 14 are both matched with the diameter of the core rod 51. Both ends of the core rod 51 are axially slidably fitted in the limit sleeve 13 and the guiding hole 14.

[0031] A positioning seat 7 is arranged on the main shaft 1. The positioning seat 7 has a positioning hole 71 arranged along the radial direction of the main shaft 1. The positioning hole 71 penetrates through the main shaft 1 and is communicated with the guiding hole 14. An annular groove 54 is formed on the core rod 51 by extending along the circumferential direction. A positioning bead 72 for cooperating with the annular groove 54 is arranged in the positioning hole 71. A spring 73 is compressively abutted on the positioning bead 72 in the positioning hole 71 to make the positioning bead 72 abut on the core rod 51. The annular groove 54 is arranged corresponding to the driving gear 4 one by one in the axial direction of the core rod 51, and the distance between any annular groove 54 and the corresponding driving gear 4 is equal. Specifically, as Figures 3 to 5 shown, the main shaft 1 has a threaded hole communicated with the guiding hole 14 along the radial direction. The positioning seat 7 is cylindrical, and one end has an external thread and is connected to the threaded hole. The positioning hole 71 is coaxially arranged through the positioning seat 7. A threaded plug 74 is fitted at one end of the positioning hole 71 departing from the main shaft 1. Both ends of the spring 73 are respectively abutted on the positioning bead 72 and the threaded plug 74. Two positioning seats 7 are symmetrically arranged along the radial direction of the main shaft 1.

[0032] One end of the main shaft 1 is coaxially connected with a clutch 10, and the other end is rotatably supported in the box body 8 through a bearing. A rotatable shift fork shaft 91 penetrates through the box body 8. The shift fork shaft 91 is arranged orthogonally to the main shaft 1, and a shift fork 92 is arranged at the inner end. One end of the core shaft 5 departing from the clutch 10 penetrates out of the main shaft 1 and is provided with a shift fork disc 56. An annular shift fork groove 55 is formed on the shift fork disc 56 by extending along the circumferential direction. The shift fork 92 is fitted in the shift fork groove 55.

[0033] As Figure 1 、 Figure 3 and Figure 4 shown, an outer end of the shift fork shaft 91 has a shift fork connecting rod 93 extending along the radial direction. A gear position plate 94 corresponding to the shift fork connecting rod 93 is arranged on the box body 8. An arc-shaped gear position groove is arranged on the gear position plate 94. A sliding sleeve 95 capable of moving along the gear position groove is arranged in the gear position groove. The sliding sleeve 95 is connected to the shift fork connecting rod 93. An end of the shift fork connecting rod 93 is extendedly connected with a shift lever 96.

[0034] During use, a plurality of limit holes are provided on the main shaft, and the inner ring of the driving gear rotatably sleeved on the main shaft is evenly provided with limit grooves corresponding to the number of limit holes. When the shaft core is placed in the core hole of the main shaft, the boss fixed on the shaft core can abut against the bottom below the corresponding gear locking block when the shaft core is moved, so that the locking block protrudes from the surface of the main shaft and is engaged with the limit groove, as Figure 2 shown. When the mandrel moves axially, the balls roll relative to the surface of the mandrel in the limit holes, and thus roll onto the annular boss along the guiding surface of the mandrel, so that the balls protrude from the limit holes and are engaged with the driving gear. In this way, when the main shaft rotates, it can drive the driving gear of the corresponding gear to rotate, thereby realizing gear shifting. Since the shifting mechanism adopts the structure of two shafts, namely the main shaft and the countershaft, compared with the current mainstream three-shaft gearbox, the clearance space between the driving gears needs to be less, and the required length of the shaft is reduced, reducing the overall volume of the gearbox.

[0035] The above are only the preferred embodiments of the present invention and do not limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A gear shifting mechanism, characterized in that: The invention comprises a main shaft (1) and a secondary shaft (2) arranged in parallel, wherein a plurality of driven gears (3) are fixedly arranged side by side on the secondary shaft (2); a driving gear (4) is relatively rotatably sleeved on the main shaft (1) and is arranged to mesh with the driven gears (3); the main shaft (1) has a coaxially arranged core hole (11), a core shaft (5) is axially movably fitted in the core hole (11), the core shaft (5) comprises a core rod (51) and an annular boss (52) formed on the core rod (51) and protruding in the radial direction, the two sides of the annular boss (52) having guide surfaces (53) formed with gradually decreasing diameters; the main shaft (1) has a core hole (11) arranged to pass through the core hole (11) in the radial direction. The limiting holes (12) are arranged in a one-to-one correspondence with the driving gears (4), and at least two of the limiting holes (12) are evenly distributed along the circumference of the main shaft (1); the inner ring of the driving gear (4) has a plurality of evenly distributed limiting grooves (41), and the number of the limiting grooves (41) is N times the number of the limiting holes (12), where N is a natural number; a locking block (6) is arranged in the limiting hole (12) and can move in the radial direction of the main shaft (1), and the locking block (6) can slide along the guide surface (53) to the annular boss (52) during the axial movement of the core shaft (5), so that the locking block (6) passes through the main shaft (1) and fits in the limiting groove (41).

2. The shift mechanism according to claim 1, characterized in that: The locking block (6) is a ball bearing disposed in the limiting hole (12); the diameter of the ball bearing is smaller than the diameter of the limiting hole (12), and the ball bearing is clearance-fitted in the limiting hole (12).

3. The shift mechanism according to claim 1 or 2, characterized in that: The limiting groove (41) is in an arc shape and is arranged to penetrate along the axial direction of the driving gear (4); the width of the limiting groove (41) matches the diameter of the limiting hole (12).

4. The shift mechanism according to claim 1, characterized in that: One end of the core hole (11) passes through the main shaft (1) and is installed with a limiting sleeve (13), and the other end has a coaxially arranged guide hole (14), the inner diameters of the limiting sleeve (13) and the guide hole (14) both match the diameter of the core rod (51), and the two ends of the core rod (51) can be axially slidably fitted in the limiting sleeve (13) and the guide hole (14).

5. The shift mechanism according to claim 4, characterized in that: The main shaft (1) is provided with a positioning seat (7), the positioning seat (7) having a positioning hole (71) arranged along the radial direction of the main shaft (1), the positioning hole (71) passing through the main shaft (1) and intersecting with the guide hole (14); the core rod (51) has an annular groove (54) extending in the circumferential direction, the positioning hole (71) has a positioning bead (72) for cooperating with the annular groove (54), the positioning hole (71) has a spring (73) compressively abutting against the positioning bead (72) so that the positioning bead (72) abuts against the core rod (51); the annular groove (54) is arranged in a one-to-one correspondence with the driving gear (4) in the axial direction of the core rod (51), and the distance between any annular groove (54) and the corresponding driving gear (4) is equal.

6. The shift mechanism according to claim 5, characterized in that: The main shaft (1) has a threaded hole radially penetrating the guide hole (14); the positioning seat (7) is cylindrical and has an external thread at one end, and is connected to the threaded hole; the positioning hole (71) is coaxially penetrating the positioning seat (7); the end of the positioning hole (71) facing away from the main shaft (1) is equipped with a threaded plug (74); and the two ends of the spring (73) are respectively abutted against the positioning bead (72) and the threaded plug (74).

7. The shift mechanism according to claim 5 or 6, characterized in that: Two positioning seats (7) are symmetrically arranged along the radial direction of the main shaft (1).

8. A gearbox, comprising a housing (8), characterized in that: The box body (8) is provided with a shift mechanism as claimed in any one of claims 1 to 7.

9. The gearbox according to claim 8, characterized in that: One end of the main shaft (1) is coaxially connected to a clutch (10), and the other end is rotatably supported in the housing (8) via a bearing; a rotatable shift fork shaft (91) is passed through the housing (8), the shift fork shaft (91) is arranged orthogonally to the main shaft (1), and a shift fork (92) is arranged at the inner end; one end of the core shaft (5) away from the clutch (10) passes through the main shaft (1) and is provided with a shift fork plate (56); an annular shift fork groove (55) is formed on the shift fork plate (56) along a circumferential direction, and the shift fork (92) is fitted in the shift fork groove (55).

10. The gearbox according to claim 9, characterized in that The outer end of the shift fork shaft (91) has a shift fork connecting rod (93) extending in the radial direction, the housing (8) has a shift plate (94) arranged corresponding to the shift fork connecting rod (93), the shift plate (94) has a shift groove in the shape of an arc, a sliding sleeve (95) is inserted into the shift groove and movable along the shift groove, the sliding sleeve (95) is connected to the shift fork connecting rod (93); the end of the shift fork connecting rod (93) is extendedly connected to a shift rod (96).

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