A battery box system

Abstract

The present invention relates to the field of vehicle battery replacement technology, and in particular, to a battery box system. The battery box system includes a battery box assembly, a base assembly, a first locking assembly and a second locking assembly. The battery box assembly includes a battery box body, a packaging frame, a first pressure plate and a second pressure plate. The first locking assembly and the second locking assembly are arranged on the base assembly. The first locking assembly includes a clamping block and a first transmission unit, and the first transmission unit drives the clamping block to rotate and lift; the second locking assembly includes a pressing block and a second transmission unit, and the second transmission unit at least drives the pressing block to lift. When the battery box assembly is locked on the base assembly, the clamping block is pressed on the side of the first pressure plate away from the base assembly, and the pressing block is pressed on the side of the second pressure plate facing the base assembly. In this way, the problem of low locking reliability of the battery box body on the vehicle is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle battery replacement, and in particular to a battery box system. Background Art

[0002] The battery box on an electric vehicle provides power for the vehicle and needs to be replaced when the power is exhausted. The principle of fixing the battery box on the vehicle is generally to lock the battery box on a supporting structure by clamping or pressing, and then place the supporting structure on the frame. In order to be stably installed on the vehicle, the supporting structure is often composed of a horizontal frame, several cross beams and ribs. The horizontal frame is locked together with the battery box to support the battery box, and the cross beams are evenly distributed in the middle of the bottom of the supporting structure to support the battery box.

[0003] However, as the vehicle shakes during driving, the battery box system will be used for a long time, and the edge of the supporting structure is more prone to deformation than the middle part, resulting in a gap between the deformed part of the edge of the supporting structure and the bottom of the battery box. The existence of the gap will reduce the locking stability of the battery box, increase the impact of bumps on the battery box body, and damage the service life of the battery box loading system. Summary of the invention

[0004] In order to solve the problem of low locking reliability of the battery box body on the vehicle, the present invention provides a battery box system, comprising:

[0005] A battery box assembly, the battery box assembly comprising a battery box body, a packaging frame, a first pressure plate and a second pressure plate; the battery box body is detachably connected to the packaging frame; the first pressure plate and the second pressure plate are detachably connected to the packaging frame respectively; a first clearance groove is provided on the first pressure plate; the first pressure plate is close to the bottom middle of the packaging frame; the second pressure plate is close to the bottom edge of the packaging frame;

[0006] A bottom bracket assembly, the bottom bracket assembly is used to support the bottom of the battery box assembly;

[0007] A first locking assembly, wherein the first locking assembly is arranged near the middle of the base assembly; the first locking assembly comprises a clamping block and a first transmission unit; the clamping block is in the shape of an elongated strip; the clamping block is adapted to the shape of the first clearance groove; the first transmission unit is detachably connected to the base assembly; the clamping block is detachably connected to the first transmission unit; the first transmission unit drives the clamping block to rotate and rise and fall; when the battery box assembly is locked to the base assembly, the clamping block is pressed against the side of the first pressure plate away from the base assembly;

[0008] A second locking assembly, wherein the second locking assembly is arranged near the edge of the base assembly; the second locking assembly comprises a tightening block and a second transmission unit; the second transmission unit is detachably connected to the base assembly; the tightening block is detachably connected to the second transmission unit; the second transmission unit at least drives the tightening block to rise and fall; when the battery box assembly is locked to the base assembly, the tightening block is pressed against the side of the second pressure plate facing the base assembly.

[0009] In some embodiments, the first transmission unit includes a first screw, a first nut, a first guide seat and a first guide unit; the first screw is rotatably connected to the base assembly; the first nut is threadedly connected to the first screw; the pressing block is detachably connected to the first nut; the first guide seat is detachably connected to the base assembly; the first nut is movably connected to the first guide seat through the first guide unit;

[0010] The first guide unit includes a first guide block, a first guide section and a second guide section; the first guide block slides with the first guide section and the second guide section respectively; the first guide section is spiral and coaxial with the first screw; the thread lead angle of the first guide section is greater than the friction angle; the second guide section is straight and parallel to the axis of the first screw; the first guide section is located on the side of the second guide section close to the base assembly.

[0011] In some embodiments, the first guide block is detachably connected to the first guide seat; the first guide section and the second guide section are sliding grooves provided on the first nut.

[0012] In some embodiments, the second transmission unit includes a second screw, a second nut, a second guide seat and a second guide unit; the second screw is rotatably connected to the base assembly; the second nut is threadedly connected to the second screw; the tightening block is detachably connected to the second nut; the second nut is movably connected to the second guide seat via the second guide unit;

[0013] The second guide unit includes a second guide block and a third guide segment; the third guide segment is linear and parallel to the axis of the second screw rod; the second guide block is slidably matched with the third guide segment.

[0014] In some embodiments, the first screw and the second screw have opposite thread directions;

[0015] The battery box system also includes a driving assembly, which drives the first screw and the second screw to rotate synchronously.

[0016] In some embodiments, the drive assembly includes a drive motor, a driving wheel, a first driven wheel, a second driven wheel and a transmission belt; the drive motor is detachably connected to the base assembly; the driving wheel is transmission-connected to the drive motor; the first driven wheel is transmission-connected to the first screw; the second driven wheel is transmission-connected to the second screw; and the transmission belt is transmission-connected to the driving wheel, multiple first driven wheels and multiple second driven wheels respectively.

[0017] In some embodiments, the tightening block is in the shape of an elongated strip; the second guide unit further comprises a fourth guide segment; the fourth guide segment is in the shape of a spiral and is coaxial with the second screw; the spiral angle of the fourth guide segment is greater than the friction angle;

[0018] The battery box assembly also includes a third pressure plate, on which is opened a second clearance groove adapted to the shape of the tightening block; when the battery box assembly is locked on the base assembly, the third pressure plate is located on the side of the second pressure plate facing the base assembly.

[0019] In some embodiments, the fourth guide segment is located on a side of the third guide segment facing the base assembly.

[0020] In some embodiments, when the battery box assembly is locked on the base assembly, the pressing force of the clamping block on the first pressure plate is greater than the pressing force of the supporting block on the second pressure plate.

[0021] In some embodiments, the surface hardness of the pressing block facing the bottom bracket assembly is greater than the surface hardness of the pressing block away from the bottom bracket assembly.

[0022] In order to solve the problem of low locking reliability of the battery box body on the vehicle, the present invention has the following advantages:

[0023] The first locking assembly is arranged near the middle of the base assembly, and drives the clamping block to descend linearly to press on the first pressure plate, thereby locking the bottom middle position of the battery box assembly; the second locking assembly is arranged near the edge of the base assembly, and drives the tensioning block to rise linearly to abut against the second pressure plate, thereby eliminating the gap between the bottom of the battery box assembly and the base assembly.

[0024] With the cooperation of the first locking assembly and the second locking assembly, the locking effect of the battery box assembly can be improved and the degree of bumping and collision of the battery box system can be reduced, thereby increasing the service life of the battery box system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a battery box system according to an embodiment is shown;

[0026] Figure 2 A schematic diagram of a battery box assembly according to an embodiment is shown;

[0027] Figure 3 A partial schematic diagram of a battery box system according to an embodiment is shown;

[0028] Figure 4 An exploded schematic diagram of a first locking assembly according to an embodiment is shown;

[0029] Figure 5 An exploded schematic diagram of a second locking assembly according to an embodiment is shown;

[0030] Figure 6 A partial schematic diagram of a drive assembly according to an embodiment is shown.

[0031] Figure numerals: 10 battery box assembly; 11 packaging frame; 12 first pressure plate; 13 second pressure plate; 14 third pressure plate; 20 bottom support assembly; 21 bottom support frame; 22 load-bearing beam; 30 first locking assembly; 31 clamping block; 32 first transmission unit; 321 first screw rod; 322 first nut; 323 first guide seat; 324 first guide unit; 3241 first guide block; 3242 first guide section; 3243 second guide section; 40 second locking assembly; 41 clamping block; 42 second transmission unit; 421 second screw rod; 422 second nut; 423 second guide seat; 424 second guide unit; 4241 second guide block; 4242 third guide section; 4243 fourth guide section; 50 driving assembly; 51 driving motor; 52 driving wheel; 53 first driven wheel; 54 driving belt; 55 second driven wheel. DETAILED DESCRIPTION

[0032] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, rather than implying any limitation on the scope of the present disclosure.

[0033] As used herein, the term "including" and its variants are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "based at least in part on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal" and the like is based on the orientation or position relationship shown in the accompanying drawings. These terms are mainly for better describing the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation. In addition, in addition to being used to indicate an orientation or position relationship, some of the above terms may also be used to indicate other meanings, such as the term "upper" may also be used to indicate a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to the specific circumstances. In addition, the terms "install", "set", "provided with", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be an internal connection between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances. In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0034] During long-term driving of the vehicle, the battery box system mounted on the vehicle body is often bumped. The battery box assembly 10 is locked on the bottom bracket assembly 20. The bottom bracket 21 is rectangular, and the width direction is parallel to the driving direction of the vehicle. As the battery box bumps, the two ends of the bottom bracket 21 in the length direction are more likely to deform than the middle part, resulting in a loose connection between the ends of the bottom bracket 21 in the length direction and the battery box. The presence of the gap will cause the battery box to collide frequently, reduce the locking stability, and gradually increase the impact of the bumps on the battery box, which will damage the service life of the battery box.

[0035] This embodiment discloses a battery box system, such as Figure 1 As shown, it may include: a battery box assembly 10 , a base assembly 20 , a first locking assembly 30 and a second locking assembly 40 .

[0036] like Figure 2 As shown, the battery box assembly 10 may include a battery box body, a packaging frame 11, a first pressure plate 12 and a second pressure plate 13. The battery box body may be detachably connected to the packaging frame 11, and the packaging frame 11 is used to facilitate fixing the battery box as a whole. The first pressure plate 12 and the second pressure plate 13 may be detachably connected to the packaging frame 11, respectively, and the first pressure plate 12 and the second pressure plate 13 are both arranged at the bottom of the packaging frame 11. A first clearance groove may be provided on the first pressure plate 12. The first pressure plate 12 may be close to the middle of the bottom of the packaging frame 11, and the second pressure plate 13 may be close to the bottom edge of the packaging frame 11. As a preferred embodiment, the second pressure plate 13 may be located at the end of the packaging frame 11 in the length direction.

[0037] like Figure 3 As shown, the bottom bracket assembly 20 may include a bottom bracket 21 and a load-bearing beam 22. The bottom bracket 21 may be a rectangular frame. When the bottom bracket 21 is installed on the vehicle, the width direction of the bottom bracket 21 is parallel to the driving direction of the vehicle. It should be understood that the bottom bracket 21 may also be other shapes. The bottom bracket 21 may support the bottom of the battery box assembly 10, and the load-bearing beam 22 detachably connected to the bottom bracket 21 plays the role of bearing weight and fixing the position of the battery box on the car. The load-bearing beam 22 is composed of two cross beams, which are perpendicular to the long sides of the bottom bracket 21 and are provided with ribs near the edge of the bottom bracket 21. The center of the bottom bracket 21 has a high connection stability with the battery box assembly 10, and the gap between the edge of the bottom bracket 21 and the bottom of the packaging frame 11 will gradually increase as the vehicle bumps.

[0038] like Figure 1 As shown, the first locking assembly 30 is arranged near the middle of the bottom support assembly 20, and the first locking assembly 30 may include a clamping block 31 and a first transmission unit 32. The clamping block 31 is in an elongated strip shape, which is adapted to the shape of the first clearance groove. The first transmission unit 32 may be detachably connected to the bottom support assembly 20, and the clamping block 31 may be detachably connected to the first transmission unit 32, and the first transmission unit 32 may drive the clamping block 31 to rotate and rise and fall.

[0039] When locking the battery box assembly 10, first use the first transmission unit 32 to drive the clamping block 31 to rise to a certain height, and rotate the clamping block 31 by a certain angle so that the clamping block 31 is accurately aligned with the first clearance groove. Then, the battery box assembly 10 is vertically lowered onto the base assembly 20, so that the clamping block 31 passes through the first clearance groove and reaches the top of the first pressure plate 12. Then, the clamping block 31 is driven to descend and rotate, so that the clamping block 31 is misaligned with the first clearance groove, and the clamping block 31 is pressed against the upper side of the first pressure plate 12. Thereby, the bottom middle position of the battery box assembly 10 is locked. That is, when the battery box assembly 10 is locked on the base assembly 20, the clamping block 31 is pressed against the side of the first pressure plate 12 facing away from the base assembly 20.

[0040] The second locking assembly 40 is arranged near the edge of the bottom bracket assembly 20. As a preferred embodiment, when the bottom bracket 21 is a rectangular frame, the second locking assembly 40 can be located at the end of the bottom bracket 21 in the length direction. The second locking assembly 40 can include a tightening block 41 and a second transmission unit 42. The second transmission unit 42 is detachably connected to the bottom bracket assembly 20, and the tightening block 41 is detachably connected to the second transmission unit 42. The second transmission unit 42 can at least drive the tightening block 41 to rise and fall. When the battery box assembly 10 is locked, the second transmission unit 42 can drive the tightening block 41 to rise until the tightening block 41 is pressed against the lower side of the second pressure plate 13, that is, the tightening block 41 is pressed against the side of the second pressure plate 13 facing the bottom bracket assembly 20. The upward tightening action of the tightening block 41 helps to eliminate the gap between the bottom of the battery box assembly 10 and the deformed bottom bracket assembly 20, so that the battery box assembly 10 is stably mounted on the bottom bracket assembly 20.

[0041] With the cooperation of the first locking assembly 30 and the second locking assembly 40, the locking effect of the battery box assembly 10 can be improved and the degree of bumping and collision between the battery box assembly 10 and the base assembly 20 can be reduced, thereby increasing the service life of the battery box system.

[0042] In some embodiments, Figure 4 As shown, the first transmission unit 32 may include a first screw rod 321, a first nut 322, a first guide seat 323 and a first guide unit 324. The first guide seat 323 may be detachably connected to the base assembly 20, the first screw rod 321 may be rotatably connected to the base assembly 20, the first nut 322 is threadedly connected to the first screw rod 321, and the first nut 322 is movably connected to the first guide seat 323 through the first guide unit 324. The first nut 322 may be lifted and lowered by being threadedly connected to the first screw rod 321, and moves relative to the first guide seat 323 through the first guide unit 324. The pressing block 31 is detachably connected to the first nut 322, so that it is lifted and lowered along with the movement of the first nut 322.

[0043] The first guide unit 324 may include a first guide block 3241, a first guide section 3242, and a second guide section 3243. The first guide block 3241 may be slidably matched with the first guide section 3242 and the second guide section 3243, respectively. The first guide section 3242 may be spiral and coaxial with the screw, and the thread lead angle of the first guide section 3242 is greater than the friction angle. The second guide section 3243 is linear and parallel to the axis of the first screw 321. The first guide section 3242 is located on a side of the second guide section 3243 close to the bottom bracket assembly 20.

[0044] The first guide block 3241 is guided by the spiral first guide section 3242, so that the first nut 322 can be driven by the first screw rod 321 to be lifted and lowered while rotating. The first guide block 3241 is guided by the linear second guide section 3243, so that the first nut 322 can be driven by the first screw rod 321 to be lifted and lowered.

[0045] In some embodiments, Figure 4 As shown, the first guide block 3241 is detachably connected to the first guide seat 323. The first guide seat 323 is fixed relative to the bottom bracket 21, so the position of the first guide block 3241 is also fixed. The first guide section 3242 and the second guide section 3243 can be a slide groove opened on the first nut 322. When the first nut 322 rotates, the first guide block 3241 can slide in the first guide section 3242 and the second guide section 3243 relative to the first nut 322. When the first guide block 3241 is in the first guide section 3242, the first nut 322 can be raised and lowered while rotating; when the first guide block 3241 is in the second guide section 3243, the first nut 322 can be raised and lowered linearly.

[0046] In some embodiments, Figure 5 As shown, the second transmission unit 42 may include a second screw rod 421, a second nut 422, a second guide seat 423 and a second guide unit 424. The second guide seat 423 may be detachably connected to the base assembly 20, the second screw rod 421 may be rotatably connected to the base assembly 20, and the second nut 422 is threadedly connected to the second screw rod 421; the second nut 422 and the second guide seat 423 are movably connected via the second guide unit 424, and the second nut 422 may be raised and lowered via the threaded connection with the first screw rod 321, and move relative to the guide seat via the first guide unit 324. The tightening block 41 is detachably connected to the second nut 422, so that it is raised and lowered along with the movement of the second nut 422.

[0047] The second guide unit 424 may include a second guide block 4241 and a third guide section 4242. The third guide section 4242 is linear and parallel to the axis of the second screw rod 421. The second guide block 4241 may be block-shaped, and may be provided with a protruding cylinder on a surface close to the second nut 422, and the cylindrical surface of the cylinder may abut against the inner surface of the third guide section 4242, so that the second guide block 4241 may be slidably matched with the third guide section 4242. The second nut 422 may rise until the second guide block 4241 abuts against one end of the third guide section 4242 close to the tightening block 41.

[0048] The specific scheme of the second transmission unit 42 is similar to that of the first transmission unit 32, which helps to unify the transmission mode and thus facilitates processing.

[0049] In some embodiments, Figure 3 As shown, the battery box system also includes a driving assembly 50, which can drive the first screw 321 and the second screw 421 to rotate synchronously. The first screw 321 and the second screw 421 have opposite thread rotation directions, which can achieve the purpose of opposite lifting and lowering directions of the clamping block 31 and the pressing block 41. When the clamping block 31 descends to press the battery box assembly 10, the pressing block 41 rises to press the battery box assembly 10, thereby improving the locking effect of the battery box assembly 10 and reducing the degree of bumping and collision of the battery box system, thereby improving the service life of the battery box system. In addition, the first screw 321 and the second screw 421 share the same driving structure, which can achieve the purpose of simplifying the driving structure.

[0050] In some embodiments, Figure 3 and Figure 6 As shown, the driving assembly 50 may include a driving motor 51, a driving wheel 52, a first driven wheel 53, a second driven wheel 55 and a transmission belt 54. The driving motor 51 is detachably connected to the base assembly 20, and the driving wheel 52 is transmission-connected to the driving motor 51. The first driven wheel 53 is transmission-connected to the first screw rod 321, and the second driven wheel 55 is transmission-connected to the second screw rod 421. The transmission belt 54 is transmission-connected to the driving wheel 52, the plurality of first driven wheels 53 and the plurality of second driven wheels 55, respectively. When the driving motor 51 is running, the driving wheel 52 rotates and drives the plurality of first driven wheels 53 and the plurality of second driven wheels 55 to rotate simultaneously through the conveyor belt, so that the pressing blocks 31 of the plurality of first locking assemblies 30 and the pressing blocks 41 of the plurality of second locking assemblies 40 are lifted and lowered simultaneously.

[0051] In another embodiment, if Figure 5As shown, the clamping block 41 can be in the shape of an elongated strip. The second guide unit 424 can also include a fourth guide section 4243, which is spiral and coaxial with the second screw 421. When the second nut 422 rotates, the second guide block 4241 can slide relatively in the fourth guide section 4243. When the second guide block 4241 is in the fourth guide section 4243, the second nut 422 descends while rotating. The thread lead angle of the fourth guide section 4243 is greater than the friction angle, which is conducive to achieving the nut's rising and rotating to a certain extent. This is because when the angle of the spiral groove is large, it can provide a larger component force to overcome the friction force, making it easier for the nut to simultaneously achieve rotation and rising motion under the action of the screw.

[0052] like Figure 1 As shown, the battery box assembly 10 may further include a third pressure plate 14, on which a second clearance groove matching the shape of the top tightening block 41 is provided. When the battery box assembly 10 is locked on the bottom bracket assembly 20, the third pressure plate 14 is located on the side of the second pressure plate 13 facing the bottom bracket assembly 20. The final position of the top tightening block 41 is located between the second pressure plate 13 and the third pressure plate 14. Thus, the third pressure plate 14 can play a limiting role and prevent the battery box frame assembly from being deflected to a large extent relative to the bottom bracket assembly 20.

[0053] In some embodiments, Figure 5 As shown, the fourth guide section 4243 is located on the side of the third guide section 4242 facing the bottom bracket assembly 20. The last action of the clamping block 41 moving toward the second pressure plate 13 is to rise while rotating. Therefore, when the surface of the second pressure plate 13 is worn to varying degrees, the clamping effect can be improved by the rotation and tightening of the clamping block 41, thereby minimizing the gap as much as possible.

[0054] In some embodiments, when the battery box assembly 10 is locked on the bottom bracket assembly 20, the pressing force of the pressing block 31 on the first pressure plate 12 can be greater than the pressing force of the pressing block 41 on the second pressure plate 13, so that the pressing block 41 has a tendency to press upward to eliminate the gap caused by the bump, and the main force of the battery box assembly 10 fixed on the bottom bracket assembly 20 depends on the downward pressing force of the pressing block 31, which can improve the stability of the battery box assembly 10. If the force of the pressing block 41 is too large, the forces of the pressing block 41 and the pressing block 31 on the battery box assembly 10 are opposite and there is a gap, which will cause a large torque at the bottom of the battery box, which is not conducive to the stability of the battery box assembly 10. The present invention can avoid this to a certain extent.

[0055] In some embodiments, the surface hardness of the clamping block 31 facing the bottom bracket assembly 20 can be greater than the surface hardness of the pressing block 41 away from the bottom bracket assembly 20, that is, when the bottom bracket assembly 20 is fixed on the vehicle, the lower surface hardness of the clamping block 31 is greater than the upper surface hardness of the pressing block 41. With a large surface hardness, the clamping block 31 is not easy to wear and can achieve a large clamping force; with a small surface hardness, the upper surface of the pressing block 41 will deform when pressing against the second pressure plate 13, so that when a gap is generated between the pressing block 41 and the lower surface of the second pressure plate 13, the upper surface of the pressing block 41 will expand slightly to fill the gap, thereby improving the effect of eliminating the gap.

[0056] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in actual applications, various changes may be made thereto in form and detail without departing from the scope of the present disclosure.

Claims

1. A battery box system, characterized in that: The battery box system comprises: A battery box assembly, the battery box assembly comprising a battery box body, a packaging frame, a first pressure plate and a second pressure plate; the battery box body is detachably connected to the packaging frame; the first pressure plate and the second pressure plate are detachably connected to the packaging frame respectively; a first clearance groove is provided on the first pressure plate; the first pressure plate is close to the bottom middle of the packaging frame; the second pressure plate is close to the bottom edge of the packaging frame; A bottom bracket assembly, the bottom bracket assembly is used to support the bottom of the battery box assembly; A first locking assembly, wherein the first locking assembly is arranged near the middle of the base assembly; the first locking assembly comprises a clamping block and a first transmission unit; the clamping block is in the shape of an elongated strip; the clamping block is adapted to the shape of the first clearance groove; the first transmission unit is detachably connected to the base assembly; the clamping block is detachably connected to the first transmission unit; the first transmission unit drives the clamping block to rotate and rise and fall; when the battery box assembly is locked to the base assembly, the clamping block is pressed against the side of the first pressure plate away from the base assembly; A second locking assembly, wherein the second locking assembly is arranged near the edge of the bottom bracket assembly; the second locking assembly comprises a tightening block and a second transmission unit; the second transmission unit is detachably connected to the bottom bracket assembly; the tightening block is detachably connected to the second transmission unit; the second transmission unit at least drives the tightening block to rise and fall; when the battery box assembly is locked to the bottom bracket assembly, the tightening block is pressed against the side of the second pressure plate facing the bottom bracket assembly; The first transmission unit comprises a first screw, a first nut, a first guide seat and a first guide unit; the first screw is rotatably connected to the base assembly; the first nut is threadedly connected to the first screw; the pressing block is detachably connected to the first nut; the first guide seat is detachably connected to the base assembly; the first nut is movably connected to the first guide seat through the first guide unit; The first guide unit includes a first guide block, a first guide section and a second guide section; the first guide block slides with the first guide section and the second guide section respectively; the first guide section is spiral and coaxial with the first screw; the thread lead angle of the first guide section is greater than the friction angle; the second guide section is straight and parallel to the axis of the first screw; the first guide section is located on the side of the second guide section close to the base assembly.

2. A battery box system according to claim 1, characterized in that: The first guide block is detachably connected to the first guide seat; the first guide section and the second guide section are sliding grooves provided on the first nut.

3. A battery box system according to claim 1, characterized in that: The second transmission unit comprises a second screw, a second nut, a second guide seat and a second guide unit; the second screw is rotatably connected to the base assembly; the second nut is threadedly connected to the second screw; the tightening block is detachably connected to the second nut; the second nut is movably connected to the second guide seat via the second guide unit; The second guide unit includes a second guide block and a third guide segment; the third guide segment is linear and parallel to the axis of the second screw rod; the second guide block is slidably matched with the third guide segment.

4. A battery box system according to claim 3, characterized in that: The first screw and the second screw have opposite thread directions; The battery box system also includes a driving assembly, which drives the first screw and the second screw to rotate synchronously.

5. A battery box system according to claim 4, characterized in that: The driving assembly includes a driving motor, a driving wheel, a first driven wheel, a second driven wheel and a transmission belt; the driving motor is detachably connected to the base assembly; the driving wheel is drivingly connected to the driving motor; the first driven wheel is drivingly connected to the first screw; the second driven wheel is drivingly connected to the second screw; and the transmission belt is respectively drivingly connected to the driving wheel, multiple first driven wheels and multiple second driven wheels.

6. A battery box system according to claim 3, characterized in that: The tightening block is in the shape of an elongated strip; the second guide unit further comprises a fourth guide segment; the fourth guide segment is in the shape of a spiral and is coaxial with the second screw; the spiral angle of the fourth guide segment is greater than the friction angle; The battery box assembly also includes a third pressure plate, on which is opened a second clearance groove adapted to the shape of the tightening block; when the battery box assembly is locked on the base assembly, the third pressure plate is located on the side of the second pressure plate facing the base assembly.

7. A battery box system according to claim 6, characterized in that: The fourth guide section is located on a side of the third guide section facing the bottom bracket assembly.

8. A battery box system according to claim 1, characterized in that: When the battery box assembly is locked on the base assembly, the pressing force of the pressing block on the first pressure-bearing plate is greater than the pressing force of the pressing block on the second pressure-bearing plate.

9. A battery box system according to claim 8, characterized in that: The surface hardness of the pressing block facing the bottom bracket assembly is greater than the surface hardness of the pressing block away from the bottom bracket assembly.

Images