Differential steering wheel driving device

Abstract

The utility model discloses a differential steering wheel driving device, and relates to the technical field of AGV robots. The encoder assembly is arranged on the first substrate, and the encoder assembly comprises an encoder body and an encoder gear; the slewing bearing comprises an inner ring and an outer ring which rotate relative to each other, the inner ring is fixed to the first base plate, the outer ring is provided with a gear ring and meshed with the encoder gear, and the outer ring is used for being connected with the AGV robot; the second base plate is hinged to the bottom of the first base plate; and the two driving mechanisms are arranged at the bottom of the second substrate. Steering is achieved through operation of the two driving wheels at different speeds, the encoder records the steering angle during steering, the power-off memory function is achieved, the AGV robot does not need to find the zero point position when started again, reference positioning can be conducted through the positioning pin during installation, and therefore the steering precision of a follow-up device is improved; and the double wheels can be ensured to always land at the same time within a certain gradient range, so that better load bearing is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of AGV robots, in particular to a differential steering wheel driving device. Background Art

[0002] With the rapid popularization of AGV robot technology in China in recent years, various forms of AGV have emerged one after another, the body structure is becoming more and more compact, and the degree of automation control is getting higher and higher, which also puts higher requirements on AGV manufacturers. Especially in the fields of electric forklifts, construction robots, cleaning robots, etc., the demand for AGV power systems with high carrying capacity, small space structure and easy control is becoming more and more urgent.

[0003] At present, steering wheel drive is a common driving mode in AGV robots, especially in heavy-load conditions, which basically adopt steering wheel drive. The commonly used steering wheel is a horizontal steering wheel, including walking and steering mechanisms, but due to the limitations of the steering structure, the entire steering wheel is large and bloated, and cannot guarantee the driving stability and steering accuracy of the steering wheel under heavy load conditions. Utility Model Content

[0004] The utility model aims to solve the problems in the prior art and proposes a differential steering wheel driving device which can be overloaded and can ensure the stability of movement and steering accuracy when overloaded.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A differential steering wheel driving device, comprising:

[0007] a first substrate;

[0008] An encoder assembly is disposed on the first substrate, and the encoder assembly includes an encoder body and an encoder gear;

[0009] A slewing bearing, comprising an inner ring and an outer ring that rotate with each other, the inner ring being fixed on the first substrate, the outer ring being provided with a gear ring and meshing with the encoder gear, and the outer ring being fixed to the AGV robot;

[0010] A second base plate, which is hinged to the bottom of the first base plate;

[0011] Two driving mechanisms are arranged at the bottom of the second base plate, and each driving mechanism comprises a driving wheel and a driving motor. The second base plate can rotate so that the two driving wheels are located at different heights and move forward and backward.

[0012] Furthermore, the two driving wheels are located on the same axis, and the axis is perpendicular to the hinged rotation axis of the first base plate and the second base plate.

[0013] Furthermore, a first mounting hole and a second mounting hole are provided on the first substrate, the inner ring is connected to the first mounting hole, and the encoder body is fixedly connected in the second mounting hole.

[0014] Furthermore, a first substrate mounting block is provided at the bottom of the first substrate, the first substrate mounting block is provided with an inner hole, a second substrate mounting block is provided at the top of the second substrate, the second substrate mounting block is provided with a shaft, the shaft is inserted into the inner hole and cooperates with the inner hole to enable the first substrate and the second substrate to rotate relative to each other.

[0015] Furthermore, a graphite copper sleeve is provided in the inner hole of the first substrate mounting block, and the graphite copper sleeve is arranged outside the shaft of the second substrate mounting block.

[0016] Furthermore, the driving mechanism also includes a hub reducer, which is used to connect the driving wheel and the driving motor. The driving wheel is provided with a rubber coating on the outside, and the rubber coating material is polyurethane or rubber.

[0017] Furthermore, the two driving mechanisms are arranged centrally and symmetrically, and the driving motor is a servo motor.

[0018] Furthermore, pin holes are provided on the first substrate and the outer ring, and positioning pins are provided in the pin holes. The positioning pins can be inserted into the two pin holes to fix the outer ring on the first substrate.

[0019] Furthermore, two threaded holes are provided on the outer ring, and limiting screws are provided in the threaded holes. A limiting block is provided on the first substrate for cooperating with the limiting screws.

[0020] Furthermore, the encoder body is a multi-turn absolute encoder.

[0021] The beneficial effects of the utility model are:

[0022] In the differential steering wheel drive device of the utility model, two driving wheels run at the same speed to realize forward and backward movement, and run at different speeds to realize steering. When steering, the encoder records the steering angle and has a power-off memory function. The AGV robot does not need to find the zero point position when it is turned on again. During installation, the reference positioning can be performed through the positioning pin, thereby improving the steering accuracy of the device after the installation is completed. The first base plate and the second base plate can rotate relative to each other to realize the yaw, which can ensure that the two driving wheels always touch the ground at the same time within a certain slope range, ensuring better load-bearing capacity, so that the device can always travel smoothly on inclined or uneven ground under heavy load conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a three-dimensional structural schematic diagram of a differential steering wheel drive device proposed by the utility model;

[0024] Figure 2 This is a three-dimensional structural diagram of a driving mechanism of a differential steering wheel driving device proposed by the utility model;

[0025] Figure 3 This is a schematic diagram of the three-dimensional structure of a first substrate mounting block of a differential steering wheel driving device proposed by the utility model;

[0026] Figure 4 This is a schematic diagram of the three-dimensional structure of a slewing support of a differential steering wheel drive device proposed by the utility model;

[0027] Figure 5 This is a schematic diagram of the three-dimensional structure of a first substrate of a differential steering wheel driving device proposed by the utility model;

[0028] Figure 6 The present invention is a schematic diagram of the three-dimensional structure of an encoder component of a differential steering wheel drive device proposed by the present invention.

[0029] In the figure: 1 first substrate, 101 first mounting hole, 102 second mounting hole, 103 limit block, 2 encoder assembly, 201 encoder body, 202 encoder gear, 3 slewing bearing, 301 inner ring, 302 outer ring, 3021 positioning pin, 3022 limit screw, 4 second substrate, 5 driving mechanism, 501 driving wheel, 502 driving motor, 503 wheel hub reducer, 6 first substrate mounting block, 601 graphite copper sleeve, 7 second substrate mounting block. DETAILED DESCRIPTION

[0030] The technical solution of this patent is further described in detail below in conjunction with specific implementation methods.

[0031] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] In the description of this patent, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.

[0033] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0034] Reference Figure 1-6 A differential steering wheel drive device is used to drive an AGV robot in order to improve the smoothness of the drive device's movement when it is heavily loaded and the steering accuracy of the drive device.

[0035] The differential steering wheel driving device comprises a first substrate 1, an encoder assembly 2, a slewing bearing 3, a second substrate 4 and two driving mechanisms 5;

[0036] The encoder assembly 2 includes an encoder body 201 and an encoder gear 202. The encoder body 201 is an absolute encoder with a power-off memory function. The encoder gear 202 is axially connected to the encoder body 201. The slewing bearing 3 includes an inner ring 301 and an outer ring 302 that rotate with each other. The first substrate 1 is provided with a first mounting hole 101 and a second mounting hole 102. The encoder body 201 is fixedly connected to the second mounting hole 102. The inner ring 301 is connected to the first mounting hole 101 and is fixed to the first substrate 1. The first mounting hole 101 adopts an arc transition to avoid cable damage caused by cable scratches. An arc-shaped groove is provided on the inner ring 301 for fixing the rubber protective coil to avoid cable wear. The outer ring 302 is provided with a gear ring and meshes with the encoder gear 202. The encoder assembly 2 is used to record the real-time steering position of the differential steering wheel drive device.

[0037] The outer ring 302 is fixed to the AGV robot. When the slewing bearing 3 and the first substrate 1 are installed, since pin holes are provided on the first substrate 1 and the outer ring 302, positioning pins 3021 are provided in the pin holes. The positioning pins 3021 can be inserted into the two pin holes to fix the outer ring 302 on the first substrate 1, so as to facilitate the determination of the reference position of the outer ring 302. After installation, the positioning pins 3021 can be removed so that the outer ring 302 can rotate freely and the device can be turned. The reference position of the outer ring 302 is ensured during the installation process, thereby improving the steering accuracy when the subsequent device is turned.

[0038] The front and rear ends of the first substrate 1 are both provided with fixing holes, through which the first substrate mounting blocks 6 can be fixedly mounted on the front and rear ends of the first substrate 1. The first substrate mounting block 6 is provided with an inner hole, and the inner hole is provided with a self-lubricating graphite copper sleeve 601. The top of the second substrate 4 is provided with a second substrate mounting block 7, and the second substrate mounting block 7 is provided with a shaft, which is inserted into the graphite copper sleeve 601 and cooperates with the graphite copper sleeve 601 to form a hinged structure. The shaft can rotate inside the graphite copper sleeve 601, so that the first substrate 1 and the second substrate 4 can rotate relative to each other. When the device is moving, a certain angle of deflection can be formed through the mutual rotation of the first substrate 1 and the second substrate 4, so that when the device moves on an inclined ground, the two driving wheels 501 always touch the ground at the same time, ensuring better load-bearing, so that the device can travel smoothly on the ground of different heights under heavy load. The two driving wheels 501 are located on the same axis, and the axis is perpendicular to the hinged rotation axis of the first substrate 1 and the second substrate 4, so as to ensure that the two driving wheels 501 can always touch the ground at the same time when the ground is inclined.

[0039] The driving mechanism 5 includes a driving wheel 501, a driving motor 502 and a hub reducer 503. The hub reducer 503 is used to connect the driving wheel 501 and the driving motor 502. The driving wheel 501 is provided with a rubber coating on the outside. The rubber coating material is polyurethane or rubber. The driving motor 502 is a servo motor. The power supply voltage of the servo motor is any one of DC24V, DC48V, and DC72V, and it has a brake. The two driving mechanisms 5 are centrally symmetrically arranged at the bottom of the second substrate 4, so as to reasonably utilize the installation space and realize the function of hub driving in a smaller space. The two driving wheels 501 are coaxial. When the two servo motors drive the two driving wheels 501 to rotate at different speeds, the device can be controlled to turn. At this time, the device rotates and turns, and the encoder assembly 2 moves with the device, thereby moving outside the outer ring 302. Since the outer ring 302 is engaged with the encoder gear 202, the encoder gear 202 rotates, so that the encoder body 1 records the real-time steering position of the device.

[0040] In addition, two threaded holes are provided on the outer ring 302, and limit screws 3022 are provided in the threaded holes. The two limit screws 3022 are divided into a left limit screw and a right limit screw. A limit block 103 is provided on the first substrate 1, which is used to cooperate with the limit screws 3022, so as to limit the steering angle when the inner ring 301 of the slewing bearing 3 drives the differential steering wheel drive device to rotate, thereby avoiding the related cables of the differential steering wheel drive device from being tangled due to the lack of steering restrictions.

[0041] The working principle of the differential steering wheel drive:

[0042] When the device is installed on the AGV robot, first insert the positioning pin 3021 into the pin holes of the outer ring 302 and the first substrate 1 to fix the outer ring 302 on the first substrate 1, thereby determining the reference position of the outer ring 302, and then install the outer ring 302 on the AGV robot. After installation, the positioning pin 3021 can be removed, so that the outer ring 302 can rotate freely and the device can turn. During the installation process, the reference position of the outer ring 302 is ensured, thereby improving the steering accuracy when the device turns later;

[0043] When the device is turning, the two servo drive motors 502 control the two drive wheels 501 to rotate at different speeds, so that the device can be controlled to turn. At this time, the first substrate 1 and the second substrate 4 rotate accordingly, and the encoder assembly 2 moves with the first substrate 1. Since the outer ring 302 is engaged with the encoder gear 202, the encoder gear 202 will rotate and move outside the outer ring 302, so that the encoder body 1 records the real-time steering position of the device;

[0044] When the device travels on an inclined ground or an uneven ground, since the shaft on the second substrate mounting block 7 can rotate inside the graphite copper sleeve 601, the first substrate 1 and the second substrate 4 can rotate relative to each other to form a certain angle of deflection, so that when the device moves on the inclined ground, the two driving wheels 501 always touch the ground at the same time, ensuring better load-bearing, so that the device can travel smoothly on the inclined ground or the uneven ground under heavy load. The two driving wheels 501 are located on the same axis, and the axis is perpendicular to the hinged rotation axis of the first substrate 1 and the second substrate 4, thereby ensuring that the two driving wheels 501 can always touch the ground at the same time on the inclined ground or the uneven ground.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A differential steering wheel drive device, characterized in that: include: A first substrate (1); An encoder component (2) disposed on the first substrate (1), the encoder component (2) comprising an encoder body (201) and an encoder gear (202); A slewing bearing (3), comprising an inner ring (301) and an outer ring (302) that rotate with each other, wherein the inner ring (301) is fixed on the first substrate (1), and the outer ring (302) is provided with a gear ring and meshes with the encoder gear (202), and the outer ring (302) is used to connect to the AGV robot; A second base plate (4) hingedly connected to the bottom of the first base plate (1); Two driving mechanisms (5) are arranged at the bottom of the second base plate (4), and each of the driving mechanisms comprises a driving wheel (501) and a driving motor (502). The second base plate (4) can rotate so that the two driving wheels (501) are located at different heights and move forward and backward.

2. A differential steering wheel drive device according to claim 1, characterized in that: The two driving wheels (501) are located on the same axis, and the axis is perpendicular to the hinged rotation axis of the first base plate (1) and the second base plate (4).

3. A differential steering wheel drive device according to claim 1, characterized in that: A first mounting hole (101) and a second mounting hole (102) are provided on the first substrate (1); the inner ring (301) is connected to the first mounting hole (101); and the encoder body (201) is fixedly connected in the second mounting hole (102).

4. The differential steering wheel drive device according to claim 1, characterized in that: A first substrate mounting block (6) is provided at the bottom of the first substrate (1), the first substrate mounting block (6) is provided with an inner hole, a second substrate mounting block (7) is provided at the top of the second substrate (4), the second substrate mounting block (7) is provided with a shaft, the shaft is inserted into the inner hole and cooperates with the inner hole, so that the first substrate (1) and the second substrate (4) can rotate relative to each other.

5. A differential steering wheel drive device according to claim 4, characterized in that: A graphite copper sleeve (601) is provided in the inner hole of the first substrate mounting block (6), and the graphite copper sleeve (601) is arranged outside the axis of the second substrate mounting block (7).

6. The differential steering wheel drive device according to claim 1, characterized in that: The driving mechanism (5) further comprises a wheel hub reducer (503), wherein the wheel hub reducer (503) is used to connect the driving wheel (501) and the driving motor (502), and the driving wheel (501) is provided with a rubber coating on the outside, wherein the rubber coating material is polyurethane or rubber.

7. The differential steering wheel drive device according to claim 1, characterized in that: The two driving mechanisms (5) are arranged centrally and symmetrically, and the driving motor (502) is a servo motor.

8. The differential steering wheel drive device according to claim 1, characterized in that: Pin holes are provided on the first substrate (1) and the outer ring (302), and positioning pins (3021) are provided in the pin holes. The positioning pins (3021) can be inserted into the two pin holes to fix the outer ring (302) on the first substrate (1).

9. The differential steering wheel drive device according to claim 1, characterized in that: The outer ring (302) is provided with two threaded holes, and limit screws (3022) are provided in the threaded holes. The first substrate (1) is provided with a limit block (103) for cooperating with the limit screws (3022).

10. The differential steering wheel drive device according to claim 1, characterized in that: The encoder body (201) is a multi-turn absolute value encoder.

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