CN110091352B - Miniature large-torque high-speed joint integrated hydraulic driver - Google Patents

Abstract

The invention discloses a miniature high-torque high-speed joint integrated hydraulic driver, which comprises a mechanical structure body, a transmission chain unit, a torque and rotational speed sensor and a force and displacement sensor. Support bearing sleeve cup, front support bearing sleeve cup, two support shaft bearings, two rack fixing frames, two rack fixing frame bearings, slip ring bearings, two support shaft bearings are assembled at both ends of the support shaft, the said The transmission chain unit includes support shaft, hydraulic cylinder, piston rod, rack, spur gear, gear transmission shaft, small bevel gear, slip ring, large bevel gear. It solves the problems of high power density, high load and high frequency response, low inertia, and sensor integration of the current rotary joint robot joint drive. The use of hydraulic cylinders as driving components greatly increases the output torque and large load frequency response of the driver, and improves its performance. High acceleration following characteristics.

Description

Miniature high-torque high-speed joint with integrated hydraulic drive

technical field

The invention relates to the field of robots, in particular to a miniature high-torque high-speed joint integrated hydraulic driver.

Background technique

Rotary joint robot refers to that the movement of the robot is realized by rotating joints. Its main feature is that the two arms are connected by a rotating joint, and the relative movement between the two arms is realized by the rotating joint, and finally the target task is completed. It is widely used in intelligent robotic arms and various bionic-footed robots (humanoid biped robots, quadruped robots, hexapod robots, etc.) on automated production lines.

At present, the driving mechanism of rotary joints can be divided into servo motors and hydraulic servos. The driving mechanism of servo motors is the most widely used structural form in rotary joints. However, servo motors have low power density, limited output torque, and large load frequency response. The low speed will lead to the large volume of the robot's rotary joints, limited output torque and rotation speed, large inertia and difficulty in starting, and poor follow-up characteristics at high acceleration. Hydraulic servos are currently mainly used in large-load rotary joints, which rely on hinges and hydraulic cylinders to convert the linear motion of the hydraulic cylinder into the rotary motion of the joint or the hydraulic motor directly outputs rotary motion, but in the foot robot, the hydraulic cylinder is used for the foot. The influence of the oscillating inertia cannot be ignored in the joint drive of the type robot. At the same time, due to the compact leg space of the foot robot, the layout of the hydraulic cylinder and the hydraulic oil circuit is also a big problem. The compact layout of the hydraulic cylinder means that its corresponding force arm is small. If the same torque is output, the size of the hydraulic cylinder must be increased. , the problem is that the leg inertia and volume of the footed robot increase synchronously, and the size of the hydraulic cylinder increases and the required flow increases, resulting in the corresponding configuration of the servo valve, hydraulic oil source, etc. The size and mass of the robot are increased, which is disadvantageous for a moving footed robot.

SUMMARY OF THE INVENTION

In view of the above problems existing in the current rotary joint drive mechanism, the present invention proposes a miniature high-torque high-speed joint integrated hydraulic driver to solve the problems of high power density, large load, high frequency response, low inertia, and transmission of the current rotary joint robot joint drive. sense integration problem.

The technology adopted in the present invention is as follows: a miniature high-torque high-speed joint integrated hydraulic driver, including a mechanical structure body, a transmission chain unit, a torque and rotational speed sensor and a force and displacement sensor, the transmission chain unit is located in the mechanical structure body, so The mechanical structure body described above includes an outer casing, a rear end cover, a front end cover, a rear support bearing cup, a front support bearing cup, two support shaft bearings, two rack mounts, two rack mount bearings, and a slide. Ring bearing, the two support shaft bearings are respectively assembled in the rear support bearing cup and the front support bearing cup located at both ends of the support shaft, the rear end cover is attached to the end face of the rear support bearing cup, and the front end cover is attached to the front support On the end face of the bearing cup, two rack mounts are located inside the outer casing, each rack mount is fitted with a rack mount bearing, and the slip ring bearing is mounted on the slip ring and is located between the two rack mounts , the transmission chain unit includes a support shaft, a hydraulic cylinder, a piston rod, a rack, a spur gear unit, a gear transmission shaft, a small bevel gear, a slip ring, and a large bevel gear, and the gear rotating shaft passes through the assembly hole on the support shaft , both ends are fixed on the slip ring, the spur gear unit and the small bevel gear are fixed on the gear transmission shaft, the large bevel gear meshes with the small bevel gear and is fixed inside the outer casing, the rack is meshed with the spur gear unit, the two The end is fixed on the rack fixing frame, one end of the piston rod is fixedly connected with the rack, and the other end is assembled in the hydraulic cylinder, the torque and rotational speed sensor is located inside the rear end cover, and the force and displacement sensor is located at the bottom of the hydraulic cylinder. The present invention also has the following technical features:

1. The hydraulic cylinder and the support shaft do not move. The hydraulic cylinder drives the piston rod to move in a straight line. The rack fixed at one end of the piston rod meshes with the spur gear unit to drive the spur gear unit to rotate around the gear transmission shaft. The small bevel gear on the gear transmission shaft meshes with the large bevel gear fixed on the outer casing to convert the rotary motion around the gear transmission shaft into the rotary motion around the support shaft.

2. The force and displacement sensor realizes the servo control of the hydraulic cylinder and monitors the displacement and output information of the hydraulic cylinder. The torque and rotational speed sensor monitors the rotational speed and torque output by the hydraulic driver, and realizes the Large closed-loop servo control of the position and force of the hydraulic drive.

3. The spur gear unit includes two gears, the end faces of the two gears are fixedly connected, and the tooth tops of the two gears are staggered by a certain angle. When the spur gear unit and the rack are in meshing transmission, they always keep the tooth surfaces in close contact. , so that the tooth surface of one gear and the lower tooth surface of the rack closely fit, and the tooth surface of the other gear closely fits the upper tooth surface of the rack, ensuring that the rack and the spur gear unit are always in close contact during the transmission process, eliminating the need for reciprocating The gap caused in the transmission process improves the transmission accuracy, avoids the collision between the gear and the rack during transmission, and increases the life of the rack and pinion.

Advantages and beneficial effects of the present invention: the present invention is used for a rotary joint type robot, because the compact closed transmission chain is used to realize the conversion of the linear motion of the hydraulic cylinder into the joint rotary motion, and to ensure the sealing and lubrication of the transmission chain unit, greatly increasing the Its life span is reduced, and the friction loss of transmission is reduced; the integrated arrangement of transmission elements greatly reduces the size of the driver, greatly improves the power density ratio of the driver, reduces the inertia of the driver, and makes it easy to start and brake; integrated fusion of multiple sensors , it can sense the key parameters such as the internal force and displacement of the driver, and at the same time reduce the connection parts and increase the integration degree of the system; the use of hydraulic cylinder as the driving element greatly increases the output torque and large load frequency response of the driver, and improves its high acceleration follow-up Features, high-speed follow-up characteristics; the internal drive shaft can be designed as direct connection and hinge type, and the use of different drive shafts can make the drive size adapt to more applications; by choosing different integrated sensor feedback information, the hydraulic cylinder servo loop can be realized Control and joint big loop servo control and other control modes, greatly improve its control performance.

Description of drawings

Figure 1 is a schematic structural diagram of a miniature high-torque high-speed joint integrated hydraulic driver;

Figure 2 is an exploded view of a miniature high-torque high-speed joint integrated hydraulic driver;

Figure 3 is a supplementary exploded view of a miniature high-torque high-speed joint integrated hydraulic drive;

Figure 4 is a schematic structural diagram of a transmission chain unit;

Figure 5 is a schematic structural diagram of a spur gear unit;

Figure 6 is a side view of the structure of the spur gear unit.

Detailed ways

The present invention will be further described below according to the accompanying drawings of the description:

Example 1

As shown in Figure 1-4, a miniature high-torque high-speed joint integrated hydraulic driver includes a mechanical structure body 1, a transmission chain unit 2, a torque and rotational speed sensor 3-1 and a force and displacement sensor 3-2. The transmission chain The unit 2 is located in the mechanical structure body 1, and the mechanical structure body 1 includes an outer casing 1-1, a rear end cover 1-2, a front end cover 1-3, a rear support bearing cup 1-4, and a front support bearing cup 1-5, two support shaft bearings 1-6, two rack mounts 1-7, two rack mount bearings 1-8, slip ring bearings 1-9, two support shaft bearings 1-6 respectively It is assembled in the rear support bearing cup 1-4 and the front support bearing cup 1-5 located at both ends of the support shaft 2-1. The rear end cover 1-2 is fitted on the end face of the rear support bearing cup 1-4. The cover 1-3 is fitted on the end face of the front support bearing cup 1-5, the two rack fixing frames 1-7 are located inside the outer casing 1-1, and each rack fixing frame 1-7 is equipped with a rack fixing frame The frame bearing 1-8, the slip ring bearing 1-9 are assembled on the slip ring 2-8, and are located between the two rack fixing frames 1-7. The transmission chain unit 2 includes a support shaft 2-1, a hydraulic cylinder 2-2, piston rod 2-3, rack 2-4, spur gear unit 2-5, gear transmission shaft 2-6, small bevel gear 2-7, slip ring 2-8, large bevel gear 2-9, The gear rotating shaft 2-6 passes through the assembly hole on the support shaft 2-1, and the two ends are fixedly connected to the slip ring 2-8. The spur gear unit 2-5 and the pinion bevel gear 2-7 are fixedly connected to the gear transmission shaft 2 On -6, the large bevel gear 2-9 meshes with the small bevel gear 2-7 and is fixed inside the outer casing 1-1, the rack 2-4 meshes with the spur gear unit 2-5, and both ends are fixed on the rack. On the frame 1-7, one end of the piston rod 2-3 is fixedly connected with the rack 2-4, and one end is assembled in the hydraulic cylinder 2-2. The torque and speed sensor 3-1 is located inside the rear end cover 1-2. The force and displacement sensor 3-2 is located at the bottom of the hydraulic cylinder 2-2.

As shown in Figure 2-4, in the transmission chain unit 2, the hydraulic cylinder 2-2 and the support shaft 2-1 are fixed on the body or the previous link arm, and the hydraulic cylinder 2-2 and the support shaft 2- 1 No movement occurs, the hydraulic cylinder 2-2 drives the piston rod 2-3 to move in a straight line, and the rack 2-4 fixed at one end of the piston rod 2-3 meshes with the spur gear unit 2-5 to drive the spur gear unit 2-5 to go around. The gear transmission shaft 2-6 makes a rotary motion, and the small bevel gear 2-7 fixed on the gear transmission shaft 2-6 meshes with the large bevel gear 2-9 fixed on the outer casing 1-1, which will drive the gear transmission around the gear. The rotational motion of the shaft 2-6 is transformed into a rotational motion about the support shaft 2-1.

As shown in Figure 3, the force and displacement sensor 3-2 realizes the servo control of the hydraulic cylinder 2-2 and monitors the displacement and output information of the hydraulic cylinder 2-2, and the torque and rotational speed sensor 3-1 monitors The rotational speed and torque output by the hydraulic driver, and through the control algorithm, realize the large closed-loop servo control of the position and force of the hydraulic driver.

As shown in Fig. 5, the spur gear unit 2-5 includes two gears, the end faces of the two gears are fixedly connected, the tooth tops of the two gears are staggered by a certain angle, the spur gear unit 2-5 and the rack 2-4 During meshing transmission, always keep the tooth surfaces in close contact, eliminate the gap caused by the reciprocating transmission process, improve the transmission accuracy, avoid the collision between the gear and the rack during transmission, and increase the life of the rack and pinion.

Claims (4)

1. The utility model provides a high-speed joint integrated hydraulic drive of miniature big moment of torsion, includes mechanical structure body (1), driving chain unit (2), moment speed sensor (3-1) and power and displacement sensor (3-2), driving chain unit (2) be located mechanical structure body (1), its characterized in that:

the mechanical structure body (1) comprises an outer shell (1-1), a rear end cover (1-2), a front end cover (1-3), a rear supporting bearing retainer cup (1-4), a front supporting bearing retainer cup (1-5), two supporting shaft bearings (1-6), two rack fixing frames (1-7), two rack fixing frame bearings (1-8) and a sliding ring bearing (1-9), wherein the two supporting shaft bearings (1-6) are respectively assembled in the rear supporting bearing retainer cup (1-4) and the front supporting bearing retainer cup (1-5) which are positioned at two ends of a supporting shaft (2-1), the rear end cover (1-2) is attached to the end face of the rear supporting bearing retainer cup (1-4), the front end cover (1-3) is attached to the end face of the front supporting bearing retainer cup (1-5), the two rack fixing frames (1-7) are positioned in the outer shell (1-1), the rack fixing frame bearings (1-8) are assembled on each rack fixing frame (1-7), the sliding ring bearing (1-9) is assembled on the sliding ring (2-8), the sliding ring bearing (7) is positioned between the two rack fixing frames (1-7),

the transmission chain unit (2) comprises a supporting shaft (2-1), a hydraulic cylinder (2-2), a piston rod (2-3), a rack (2-4), a straight gear unit (2-5), a gear transmission shaft (2-6), a small bevel gear (2-7), a sliding ring (2-8) and a large bevel gear (2-9), wherein the gear transmission shaft (2-6) penetrates through an assembly hole on the supporting shaft (2-1), two ends of the gear transmission shaft are fixedly connected onto the sliding ring (2-8), the straight gear unit (2-5) and the small bevel gear (2-7) are fixedly connected onto the gear transmission shaft (2-6), the large bevel gear (2-9) is meshed with the small bevel gear (2-7) and fixedly connected into the outer shell (1-1), the rack (2-4) is meshed with the straight gear unit (2-5), two ends of the rack are fixed onto a rack fixing frame (1-7), one end of the piston rod (2-3) is fixedly connected with the rack (2-4), and the other end of the piston rod is assembled into the hydraulic cylinder (2-2),

the torque and rotation speed sensor (3-1) is positioned on the inner side of the rear end cover (1-2), and the force and displacement sensor (3-2) is positioned at the bottom of the hydraulic cylinder (2-2).

2. The integrated hydraulic driver of a miniature large-torque high-speed joint as claimed in claim 1, wherein the hydraulic cylinder (2-2) and the support shaft (2-1) do not move, the hydraulic cylinder (2-2) drives the piston rod (2-3) to make linear motion, a rack (2-4) fixedly connected to one end of the piston rod (2-3) is engaged with the spur gear unit (2-5) to drive the spur gear unit (2-5) to make rotational motion around the gear transmission shaft (2-6), a small bevel gear (2-7) fixedly connected to the gear transmission shaft (2-6) is engaged with a large bevel gear (2-9) fixedly connected to the outer housing (1-1), and the rotational motion around the gear transmission shaft (2-6) is converted into rotational motion around the support shaft (2-1).

3. The integrated hydraulic actuator of the miniature large-torque high-speed joint according to claim 1, wherein the force and displacement sensor (3-2) realizes servo control of the hydraulic cylinder (2-2) and monitors displacement and output information of the hydraulic cylinder (2-2), and the torque and rotation speed sensor (3-1) monitors rotation speed and torque output by the hydraulic actuator and realizes large closed-loop servo control of the position and force of the hydraulic actuator through a control algorithm.

4. The integrated hydraulic driver of the miniature large-torque high-speed joint as claimed in claim 1, wherein the spur gear unit (2-5) comprises two gears, the end faces of the two gears are fixedly connected, the tops of the two gears are staggered by a certain angle, and the spur gear unit (2-5) and the rack (2-4) always keep tight fit between the tooth faces during meshing transmission.

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