A ground-to-air tailgate door opening and closing electric drive mechanism

Abstract

The utility model belongs to drive device technical field provides a kind of heaven and earth tail door ground door opening and closing electric drive mechanism, including tail box, pull line tightening device and electric drive device, wherein tail box includes ground door, tail box floor and the decorative plate of both sides, electric drive device is installed in the rear width center of tail box floor, electric drive device connects ground door, pull line tightening device holds ground door from side portion, the included angle between electric drive device drive ground door movement and tail box floor changes and realizes electric opening and closing, tail box is provided with lock catch device, pull line tightening device also telescopic lock catch device with the lifting of ground door can be automatically attracted and locked on.This utility model's advantage lies in only needing an electric drive device, tail door both sides are uniformly stressed, ground door gap inconsistency is not caused, reduce the influence to tail lamp and other modeling structure, offset tail door gravity moment, can slow down tail door to prevent tail door from suddenly falling due to dead weight after unlocking.

Description

Technical Field

[0001] This utility model belongs to the field of drive device technology, specifically relating to an electric drive mechanism for opening and closing a tailgate and a ground door. Background Technology

[0002] As electric vehicles become increasingly intelligent and electric, many luxury SUVs have adopted power tailgates with upper and lower sections. These tailgates consist of two sections: the upper section flips upwards, and the lower section flips downwards. Compared to traditional one-piece tailgates, these split tailgates are shorter, requiring less parking space when opening outwards, reducing the risk of hitting people behind the vehicle, and allowing for easy closing without having to move. The reduced length and area of ​​the upper section also allows for lighter weight, reducing the damping force of the hydraulic / spring rods, making manual closing easier and more user-friendly for women. Furthermore, the lower section opens flush with the trunk, facilitating easy loading and unloading of items, and can also provide seating or reclining space, expanding its usability. However, due to the weight of the doors, opening and closing the lower section, like the upper section, requires a shift in the center of gravity, requiring work to be done on gravity. Most models use electric struts mounted on both sides to minimize obstruction of items and balance the gap when closing. Because electric struts are relatively long and thick, and involve extension, retraction, and rotation, they require ample space. Therefore, hydraulic strut-type soft-close doors were developed, which in turn led to electric strut-type drive mechanisms, as seen in models such as the Land Rover Discovery 4, BMW X5, and Li Auto L9. Electric struts positioned on both sides of the rear require clearance from the tailgate and inner plastic cover, significantly impacting taillights, internal structural design, sealing, and door locks, resulting in higher costs. Furthermore, using a balance damping rod on one side while installing an electric strut on the other can cause inconsistent closing forces and uneven door gaps. Additionally, exposed electric struts are easily scratched and are unsightly. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide an electric drive mechanism for opening and closing the tailgate and tailgate, which requires only one electric drive, can achieve uniform force on both sides, consistent door gaps, and reduce the impact on the taillights and other structural features, in light of the current state of the technology.

[0004] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: an electric drive mechanism for opening and closing a tailgate and a bottom door, characterized in that it includes a tailgate, a cable tightening device, and an electric drive device. The tailgate includes a bottom door, a tailgate floor, and trim panels on both sides. The cable tightening device is arranged inside the trim panels on both sides of the tailgate at the rear of the vehicle. The electric drive device is installed in the center of the rear width of the tailgate floor and is connected to the bottom door. The cable tightening device pulls the bottom door from the side. After the electric drive device drives the bottom door to move, the angle between it and the tailgate floor changes, and electric opening and closing is achieved. A locking device is provided on the tailgate. The cable tightening device also extends and retracts with the raising and lowering of the bottom door, and the locking device can automatically engage and lock.

[0005] In the above-mentioned electric drive mechanism for opening and closing a bottom door, the pull cable tightening device includes a pull cable, a winding wheel, a rotating shaft, a torsion spring, a housing, and a guide wheel. The rotating shaft is mounted on the housing, and the housing can rotate around the rotating shaft. The pull cable is wound around the housing. The torsion spring is located inside the housing and provides deformation pre-tension force. The pull cable extends out from the housing, is guided by the guide wheel, and then connects to the bottom door. The locking device includes a latch, a latch, and a magnetic lock. After the electric drive device drives the bottom door to move, the pull cable also extends and retracts with the rise and fall of the bottom door under the deformation pre-tension action of the torsion spring. When the latch touches the latch, the magnetic lock automatically engages and locks.

[0006] In the above-mentioned electric drive mechanism for opening and closing a tailgate and a ground door, the electric drive device includes a housing and a motor, a motor reducer assembly, a main drive gear, a synchronous belt, a secondary drive gear, a lead screw, a nut, and a pull rod installed in the housing. The motor is reduced in speed by the motor reducer assembly and then drives the lead screw to rotate through the main drive gear, the synchronous belt, and the secondary drive gear. The pull rod is connected to the nut, and the nut is fitted on the lead screw. When the lead screw rotates, it drives the pull rod to move. One end of the pull rod is located inside the housing, and the other end extends out of the housing and is connected to a rod end movable joint and a ground door bracket.

[0007] In the above-mentioned electric drive mechanism for opening and closing a bottom door, the movable joint at the rod end has an outwardly convex spherical surface and an inwardly concave spherical surface. The movable joint at the rod end is covered by the upper and lower spherical covers of the bottom door bracket. The movable joint at the rod end is connected to one end of the pull rod extending out of the housing. The bottom door bracket includes an inner mounting bracket and an outer mounting bracket. The outwardly convex spherical surface and the inwardly concave spherical surface are respectively connected to the outer surface of the inner mounting bracket and the inner surface of the outer mounting bracket of the bottom door through a sliding fit ball joint. After the bottom door bracket is assembled, it is fixedly connected to the bottom door with bolts.

[0008] The tie rod in this patent can be obtained by conventional machining methods such as punching and bending, and the spherical feature can be formed by processing methods such as plastic coating or die casting.

[0009] In the above-mentioned electric drive mechanism for opening and closing a tailgate and a ground door, there are several through holes, a ball joint, and a pin on the plane at one end of the pull rod inside the housing. The ball joint is fixed to one end of the pull rod by the pin. The nut has a back cover. The inner cavity of the nut and the inner cavity of the back cover form a concave spherical surface. The ball joint can rotate flexibly around the center of the ball at a certain angle. The back cover is inserted into the nut laterally and fixed by a longitudinal insert.

[0010] In the above-mentioned electric drive mechanism for opening and closing a tailgate and a ground door, the nut has internal threads that engage with the external threads of the lead screw. The outer surface of the nut has transverse ribs that fit against the plane of the housing and can guide the sliding. Limiting blocks are provided at the front and rear of the housing and are used to limit the nut at its maximum stroke.

[0011] In the aforementioned electrically driven mechanism for opening and closing a tailgate / bottom gate, bearings are fitted at both ends of the lead screw. One bearing's outer ring is fixed to both ends of the housing and provides a limiting position, while the other bearing only provides radial limiting and does not provide axial limiting. The lead screw can rotate flexibly around its axis. The bearing type is not limited to rolling bearings or oil-impregnated bearings.

[0012] In the above-mentioned electric drive mechanism for opening and closing a tailgate and a ground gate, the lead screw has an external spline, which is nested with a secondary transmission gear. The secondary transmission gear and the main transmission gear are connected by a synchronous belt to achieve synchronous transmission.

[0013] In the above-mentioned electric drive mechanism for opening and closing a tailgate and a ground gate, the transmission shaft in the middle of the main transmission gear has a spline and is connected to the output shaft of the motor reducer assembly. When the motor reducer assembly rotates, the torque can be transmitted to the main transmission gear through the spline on the transmission shaft.

[0014] In the aforementioned electrically driven mechanism for opening and closing a tailgate and bottom door, when the electric drive device is energized, the motor drives the motor reducer assembly to rotate and transmits torque to the main drive gear through the transmission shaft. The main drive gear transmits torque to the auxiliary drive gear through the synchronous belt. The auxiliary drive gear is nested on the spline of the lead screw and drives the lead screw to rotate. The nut nested on the lead screw has its outer plane limited by the housing. When the lead screw rotates, the nut can slide along the housing limiting plane under the driving force of the screw drive. The sliding of the nut drives the pull rod to move. The other end of the pull rod is connected to the bottom door. While the joints at both ends of the pull rod rotate, one end of the pull rod moves linearly along the housing of the driver. The angle between the pull rod and the tailgate floor changes, enabling the bottom door to achieve electric opening and closing. At the same time, the pull cable in the pull cable tensioning device also extends and retracts with the rise and fall of the bottom door under the deformation and pre-tensioning action of the torsion spring. When the lock tongue touches the lock buckle, the latch automatically engages and locks.

[0015] Compared with the prior art, the advantages of this utility model are: 1. Only one electric drive unit is needed, and it is centrally located, so the force on both sides of the tailgate is even, which will not cause inconsistent gaps in the door seam. 2. The drive mechanism is designed to be concealed, reducing the corrosion caused by ultraviolet rays and rainwater, and extending its service life. 3. Due to the central arrangement, the impact on the taillights and other structural elements is reduced. Since they are not located on the sides of the rear, the arrangement of the taillights and door locks is not affected. They occupy less space and can be hidden under the cover. 4. It is designed with an independent cable tightening device, with an internal winding wheel. The cable is connected to the tailgate. The winding wheel uses a torsion spring or similar means to achieve self-tightening of the cable, which counteracts the tailgate's gravitational torque and can slowly lower the tailgate to prevent it from suddenly falling down due to its own weight after unlocking. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the electric drive mechanism for opening and closing the tailgate and bottom door of this building when it is in operation; Figure 2 This is a schematic diagram of the electric drive device; Figure 3 This is a schematic diagram of the cable tightening device; Figure 4 This is a schematic diagram of the cooperation structure between the pull rod and the bottom door bracket of the electric drive mechanism for opening and closing the bottom door of this earth-shattering tailgate; Figure 5 This is a schematic diagram of the mating structure of the main drive gear and the auxiliary drive gear. Detailed Implementation

[0017] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0018] In the diagram, the following components are included: tail box 100; bottom door 101; tail box floor 102; trim panel 103; cable tightening device 200; electric drive device 300; housing 301; motor 302; motor reducer assembly 303; main drive gear 304; synchronous belt 305; secondary drive gear 306; lead screw 307; nut 308; pull rod 309; rod end movable joint 400; convex spherical surface 401; concave spherical surface 402; bottom door bracket 500; internal mounting bracket 501; external mounting bracket 502; bearing 600; and locking device 700.

[0019] like Figure 1 As shown, the electric drive mechanism for opening and closing the tailgate includes a tailgate 100, a cable tensioning device 200, and an electric drive unit 300. The tailgate 100 includes a tailgate 101, a tailgate floor 102, and side panels 103. The cable tensioning device 200 is located within the side panels 103 of the tailgate 100. The electric drive unit 300 is installed in the center of the rear width of the tailgate floor 102 and is connected to the tailgate 101. The cable tensioning device 200 pulls the tailgate 101 from the side. After the electric drive unit 300 drives the tailgate 101 to move, the angle between it and the tailgate floor 102 changes, achieving electric opening and closing. The tailgate 101 is equipped with a locking device 700, and the pull cable tightening device 200 extends and retracts with the raising and lowering of the tailgate 101. The locking device 700 can automatically engage and lock. The biggest innovation of this patent is that only one electric drive device 300 is needed. The tailgate 101 can be opened and closed automatically by remote control or foot kick sensing, which is convenient for loading and unloading items in the trunk. With the electric drive device 300 centrally located, the tailgate is evenly stressed on both sides, which will not cause inconsistent gaps in the door. In addition, it has a hidden design, which occupies less space. The pull cable tightening device 200 enables the pull cable to tighten itself, which counteracts the gravitational torque of the tailgate and can slowly lower the tailgate to prevent it from suddenly falling down due to its own weight after unlocking.

[0020] like Figure 2 As shown, the core of this patent, the electric drive device 300 includes a housing 301 and a motor 302, a motor reducer assembly 303, a main drive gear 304, a synchronous belt 305, a secondary drive gear 306, a lead screw 307, a nut 308, and a pull rod 309 installed within the housing 301. In this patent, the housing 301 is a large-section, top-and-bottom cover type with a shallow mold cavity, making demolding easy and ensuring good internal linear dimensions. The spherical joint feature at one end of the pull rod 309 can be formed using processing methods such as plastic coating or die casting. With no clearance, it boasts rapid mass production and low cost. Motor 302, after being reduced in speed by motor reducer assembly 303, drives lead screw 307 to rotate via main drive gear 304, synchronous belt 305, and auxiliary drive gear 306. Main drive gear 304 is integrally molded onto the drive shaft, while auxiliary drive gear 306 is molded onto lead screw 307. This design results in small transmission clearance and minimal return stroke. Pull rod 309 connects to nut 308, which is fitted onto lead screw 307. When lead screw 307 rotates, it drives pull rod 309 to rotate. The lever 309 has one end located inside the housing 301, and the other end extends out of the housing 301 and is connected to the lever end movable joint 400 and the tailgate bracket 500. The entire electric drive device 300 is centrally located, which ensures that the tailgate is evenly stressed on both sides during operation, preventing inconsistent door gaps. To ensure the entire travel of the lever 309, the nut 308 has internal threads that engage with the external threads of the lead screw 307. The outer surface of the nut 308 has transverse ribs that fit against the plane of the housing 301. For guided sliding, limit stops are set before and after the housing 301 to limit the nut 308 at its maximum stroke. As a further optimization, to ensure the stability of the lead screw 307, bearings 600 are fitted at both ends of the lead screw 307. One bearing 600 has its outer ring fixed to both ends of the housing 301 and provides a limit, while the other bearing 600 only provides radial limit and not axial limit. The lead screw 307 can rotate flexibly around its axis, resulting in small axial clearance and preventing jamming. The bearing type is not limited to rolling bearings and oil-impregnated bearings, such as… Figure 5 As shown, to ensure the mutual transmission of force, the lead screw 307 has an external spline, which is nested with the auxiliary transmission gear 306. The auxiliary transmission gear 306 and the main transmission gear 304 are connected by a synchronous belt 305 to achieve synchronous transmission. The transmission shaft in the middle of the main transmission gear 304 has a spline and is connected to the output shaft of the motor reducer assembly 303. When the motor reducer assembly 303 rotates, the torque can be transmitted to the main transmission gear 304 through the spline on the transmission shaft. In this way, the force output by the motor 302 can be transmitted to the lead screw 307 after passing through the motor reducer assembly 303, the main transmission gear 304, and the auxiliary transmission gear 306.

[0021] When the electric drive unit is powered on, the motor 302 drives the motor reducer assembly 303 to rotate and transmits torque to the main drive gear 304 through the transmission shaft. The main drive gear 304 transmits torque to the auxiliary drive gear 306 through the synchronous belt 305. The auxiliary drive gear 306 is nested on the spline of the lead screw 307 and drives the lead screw 307 to rotate. The nut 308 is nested on the lead screw 307. The outer plane of the nut 308 is limited by the housing 301. When the lead screw 307 rotates, the nut 308 can slide along the limiting plane of the housing 301 under the driving force of the screw drive. The sliding of the nut 308 drives the pull rod 309 to move. The other end of the pull rod 309 is connected to the bottom door 101. While the joints at both ends of the pull rod 309 rotate, one end of the pull rod 309 moves linearly along the housing 301 of the drive unit. The angle between the pull rod 309 and the tailgate floor 102 changes, enabling the bottom door 101 to realize the electric opening and closing function.

[0022] Other examples Figure 3 As shown, the cable tightening device 200 in this patent includes a cable, a winding wheel, a rotating shaft, a torsion spring, a housing, and a guide wheel. The rotating shaft is mounted on the housing, and the housing can rotate around the rotating shaft. The cable is wound around the housing. The torsion spring is located inside the housing and provides a deformation preload. The cable extends out of the housing, is guided by the guide wheel, and then connects to the ground door 101. The latching device 700 includes a latch, a latch, and a magnetic lock. The cable in the cable tightening device 200 also extends and retracts with the rise and fall of the ground door 101 under the deformation preload of the torsion spring. When the bolt touches the latch, the latching lock automatically engages and locks. After the electric drive device 300 drives the ground door 101 to move, the pull cable also extends and retracts with the rise and fall of the ground door 101 under the deformation and pre-tensioning action of the torsion spring. When the bolt touches the latch, the latching lock automatically engages and locks. Here, this patent uses the deformation and pre-tensioning force of the torsion spring to realize the winding of the pull cable. Since one end of the pull cable is connected to the ground door 101, the pull cable can be self-tightened to counteract the gravity torque of the tailgate and can slowly lower the tailgate to prevent it from suddenly falling due to its own weight after unlocking.

[0023] like Figure 4As shown, in order to allow the lever 309 to be adjusted within a certain range when pushing the ground door 101, the lever end movable joint 400 has an outwardly convex spherical surface 401 and an inwardly concave spherical surface 402. The lever end movable joint 400 is covered by the upper and lower spherical covers of the ground door bracket 500. The lever end movable joint 400 is connected to one end of the lever 309 extending out of the housing 301. The ground door bracket 500 includes an inner mounting bracket 501 and an outer mounting bracket 502. The outwardly convex spherical surface 401 and the inwardly concave spherical surface 402 are respectively connected to the outer surface of the inner mounting bracket 501 and the inner surface of the outer mounting bracket 502 of the ground door 101 through a sliding fit ball joint. After the ground door bracket 500 is assembled, it is fixedly connected to the ground door 101 with bolts. Here, because the lever end movable joint 400 is outwardly convex... The spherical surface 401 and the concave spherical surface 402 allow for oscillation in a certain direction, rather than a rigid connection, thus ensuring the stability of opening and closing. The pull rod 309 in this patent can be obtained by conventional machining methods such as punching and bending. The spherical feature can be formed by processing methods such as plastic coating or die casting. For the connection between the other end of the pull rod 309 and the nut 308, there are several through holes, articulated balls, and pins on the plane of one end of the pull rod 309 inside the housing 301. The articulated balls are fixed to one end of the pull rod 309 by the pins. The nut 308 has a back cover. The inner cavity of the nut 308 and the inner cavity of the back cover form a concave spherical shape. The articulated balls can rotate flexibly around the center of the ball at a certain angle. The back cover is inserted laterally into the nut 308 and fixed by longitudinal inserts.

[0024] This patent allows the electric drive device 300 to automatically open and close the tailgate 101 via remote control or foot kick sensor, facilitating the loading and unloading of items in the trunk. It also features an independent cable tightening device 200 to achieve self-tightening of the cable, counteracting the tailgate's gravitational torque and allowing the tailgate to lower slowly to prevent it from suddenly dropping due to its own weight after unlocking.

[0025] The specific embodiments described herein are merely illustrative examples of the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications to the described specific embodiments or adopt similar methods to replace them, but without departing from the scope defined by the spirit of this utility model.

Claims

1. An electric drive mechanism for opening and closing a bottom door / top door, characterized in that, The device includes a tailgate, a cable retractor, and an electric drive unit. The tailgate includes a floor door, a tailgate floor, and side panels. The cable retractor is located inside the side panels of the tailgate. The electric drive unit is installed in the center of the rear width of the tailgate floor and is connected to the floor door. The cable retractor pulls the floor door from the side. After the electric drive unit drives the floor door to move, the angle between it and the tailgate floor changes, achieving electric opening and closing. The tailgate is equipped with a locking device. The cable retractor also extends and retracts with the raising and lowering of the floor door, and the locking device can automatically engage and lock.

2. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 1, characterized in that, The aforementioned cable tightening device includes a cable, a winding wheel, a rotating shaft, a torsion spring, a housing, and a guide wheel. The rotating shaft is mounted on the housing, and the housing can rotate around the rotating shaft. The cable is wound around the housing. The torsion spring is located inside the housing and provides deformation pre-tension force. The cable extends out from the housing, is guided by the guide wheel, and then connects to the ground door. The locking device includes a latch, a latch, and a magnetic lock. After the ground door is driven to move by the electric drive device, the cable also extends and retracts with the rise and fall of the ground door under the deformation pre-tension action of the torsion spring. When the latch touches the latch, the magnetic lock automatically engages and locks.

3. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 1 or 2, characterized in that, The electric drive device includes a housing and a motor, a motor reducer assembly, a main drive gear, a synchronous belt, a secondary drive gear, a lead screw, a nut, and a pull rod installed inside the housing. The motor is reduced in speed by the motor reducer assembly and then drives the lead screw to rotate via the main drive gear, the synchronous belt, and the secondary drive gear. The pull rod is connected to the nut, which is fitted onto the lead screw. When the lead screw rotates, it drives the pull rod to move. One end of the pull rod is located inside the housing, and the other end extends out of the housing and is connected to a rod end movable joint and a door bracket.

4. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 3, characterized in that, The aforementioned rod end movable joint has an outwardly convex spherical surface and an inwardly concave spherical surface. The rod end movable joint is covered by the upper and lower spherical covers of the ground door bracket. The rod end movable joint is connected to one end of the pull rod extending out of the housing. The ground door bracket includes an inner mounting bracket and an outer mounting bracket. The outwardly convex spherical surface and the inwardly concave spherical surface are respectively connected to the outer surface of the inner mounting bracket and the inner surface of the outer mounting bracket of the ground door through a sliding fit ball joint. After the ground door bracket is assembled, it is fixedly connected to the ground door with bolts.

5. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 4, characterized in that, The pull rod has several through holes, a ball joint, and a pin on one end of the shell. The ball joint is fixed to one end of the pull rod by the pin. The nut has a back cover. The inner cavity of the nut and the inner cavity of the back cover form a concave spherical surface. The ball joint can rotate flexibly around the center of the ball at a certain angle. The back cover is inserted into the nut laterally and fixed by a longitudinal insert.

6. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 5, characterized in that, The nut has internal threads that engage with the external threads of the lead screw. The outer surface of the nut has transverse ribs that fit against the plane of the housing and can guide sliding. Limiting blocks are provided at the front and rear of the housing to limit the nut at its maximum stroke.

7. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 3, characterized in that, The lead screw has bearings at both ends. One bearing's outer ring is fixed to both ends of the housing and limits its movement, while the other bearing only limits its movement radially and not axially. The lead screw can rotate flexibly around its axis.

8. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 7, characterized in that, The lead screw has an external spline, which is nested with a secondary drive gear. The secondary drive gear and the main drive gear are connected by a synchronous belt to achieve synchronous transmission.

9. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 3, characterized in that, The main drive gear has a spline on its central drive shaft, which is connected to the output shaft of the motor reducer assembly. When the motor reducer assembly rotates, the torque can be transmitted to the main drive gear through the spline on the drive shaft.

10. The electric drive mechanism for opening and closing a bottom-and-top gate according to claim 9, characterized in that, When the electric drive device is powered on, the motor drives the motor reducer assembly to rotate and transmits torque to the main drive gear through the transmission shaft. The main drive gear transmits torque to the auxiliary drive gear through the synchronous belt. The auxiliary drive gear is nested on the spline of the lead screw and drives the lead screw to rotate. The nut nested on the lead screw has its outer plane limited by the housing. When the lead screw rotates, the nut can slide along the housing limiting plane under the driving force of the screw drive. The sliding of the nut drives the pull rod to move. The other end of the pull rod is connected to the bottom door. While the joints at both ends of the pull rod rotate, one end of the pull rod moves linearly along the housing of the driver. The angle between the pull rod and the tailgate floor changes, enabling the bottom door to achieve electric opening and closing function. At the same time, the pull cable in the pull cable tensioning device also extends and retracts with the raising and lowering of the bottom door under the deformation and pre-tensioning action of the torsion spring. When the lock tongue touches the lock buckle, the magnetic lock automatically engages and locks.

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