CN210910019U

CN210910019U - Plane joint four-axis arm

Info

Publication number: CN210910019U
Application number: CN201921889552.7U
Authority: CN
Inventors: 董春禄
Original assignee: Nanjing Limaisheng Robot Co ltd
Current assignee: Nanjing Limaisheng Robot Co ltd
Priority date: 2019-11-05
Filing date: 2019-11-05
Publication date: 2020-07-03
Anticipated expiration: 2029-11-05

Abstract

The utility model discloses a four-axis mechanical arm with a plane joint, which comprises a base, wherein a first motor and a ball screw module are arranged on the base, the first motor is connected with the ball screw module through a synchronous belt, a second motor and a big arm are arranged on a nut component, a third motor and a front arm are arranged at the front end of the big arm, and a fourth motor and an end effector are arranged at the front end of the front arm; the first motor, the second motor, the third motor and the fourth motor are connected with the PLC through EtherCAT cables. This application adopts ball screw module as the primary shaft through adopting integration low pressure servo motor as arm joint axle, uses the EtherCAT cable to connect each joint for the arm quality is light, and inertia is little, and the integrated level is high, and the rate of motion is fast, and the communication bandwidth promotes, responsiveness, stability reinforcing.

Description

Plane joint four-axis arm

Technical Field

The utility model relates to an industrial robot technical field, concretely relates to plane joint four-axis arm.

Background

The Scara robot is a robot arm applied to assembly operation, generally has 2-3 rotating joints with parallel axes, is simple in structure, small in occupied area and high in movement speed, and is widely applied to the production field. The existing SCARA four-axis mechanical arm respectively drives the horizontal rotation of a big arm and a front arm and the horizontal rotation and vertical movement of a tail end mechanism by 4 motors. Wherein, the motor used for driving the big arm to rotate in the horizontal direction is positioned in the base, and the other three motors are positioned in the front arm. The main mass of the operating mode is concentrated on the fourth axis in the area was carried to current SCARA four-axis arm, and inertia is big, and rigidity is relatively weaker, can not carry out fast revolution, has restricted the operating efficiency of arm, becomes the bottleneck that improves work efficiency. On the other hand, the conventional SCARA mechanical arm consists of an electric cabinet and a mechanical arm, and is large in occupied volume, complex in assembly and difficult in field protection; the cable is led to the forearm by the base outside the protection casing, causes the robot to easily cause the cable to buckle in the motion process, has restricted the motion range of robot.

SUMMERY OF THE UTILITY MODEL

For solving current SCARA four-axis arm, inertia is big, the rigidity is weak, the running efficiency is low to and occupy bulky, the assembly is complicated, the motion range is little, the technical problem that the communication bandwidth is low, the utility model provides a plane joint four-axis arm.

The utility model adopts the technical proposal that:

a four-axis mechanical arm with a planar joint comprises a base, wherein a first motor and a ball screw module are mounted on the base, the ball screw module comprises a screw rod and a nut assembly, the first motor is connected with the screw rod through a synchronous belt, and the first motor drives the screw rod to do planar rotary motion so as to drive the nut assembly to do linear motion; the nut component is provided with a second motor and a large arm, and the second motor drives the large arm to rotate around the second shaft in a plane manner; the front end of the big arm is provided with a third motor and a front arm, and the third motor drives the front arm to rotate around a third shaft in a plane manner; the front end of the forearm is provided with a fourth motor and an end effector, and the fourth motor drives the end effector to rotate in a plane; the first motor, the second motor, the third motor and the fourth motor are all integrated low-voltage servo motors and are connected with the PLC through EtherCAT cables.

Furthermore, the integrated low-voltage servo motor is connected with a planetary reducer.

Furthermore, the second motor output shaft passes through the big arm and is installed on the nut component and is locked and positioned through the pretightening nut, and a first thrust ball bearing is arranged between the big arm and the nut component.

Furthermore, the third motor output shaft passes through the big arm and the front arm, is installed on the big arm and is locked and positioned through a pretightening nut, and a second thrust ball bearing is arranged between the big arm and the front arm.

Further, the fourth motor and the end effector are connected by a timing belt.

Further, the model of ball screw module is 1610, and the active stroke is 200 mm.

The utility model has the advantages that:

1. the ball screw module is adopted to the primary shaft of arm, moves the most quality of arm to the primary shaft for the arm lightweight, inertia is little, and the rate of motion is faster, and efficiency is higher.

2. An integrated low-voltage servo motor is used as a joint shaft of the mechanical arm, and an EtherCAT cable is used for connecting each joint, so that the mechanical arm is small in size, compact in structure, high in integration level, high in power density and good in heat dissipation effect; the cable connection is omitted, the movement range of the mechanical arm is enlarged, the communication bandwidth between the motor and the controller is improved, and the mechanical arm system is enabled to enhance the performance in the aspects of responsiveness, stability and the like.

Drawings

Fig. 1 is a schematic structural diagram illustrating a four-axis mechanical arm with a planar joint according to an embodiment of the present invention.

Detailed Description

For a better understanding of the present invention, the following examples are provided to further illustrate the present invention, but the present invention is not limited to the following examples.

Embodiment mode 1

Referring to fig. 1, a four-axis mechanical arm with a plane joint comprises a base 2, a first synchronous belt 3, a ball screw module 4, a first motor 1, a second motor 10, a third motor 11, a fourth motor 13, a big arm 9, a front arm 12, an end effector 14, a second synchronous belt 15, a first pre-tightening nut 5, a second pre-tightening nut 6, a first thrust ball bearing 7 and a second thrust ball bearing 8.

The base 2 is the carrier of the whole system and is made of an aluminium alloy material. The ball screw module 4 and the first motor 1 are vertically installed on the bottom plate through screws, the ball screw module 4 comprises a screw rod and a nut assembly 41, an output shaft of the screw rod and the first motor penetrates through the base 2 to be connected through a synchronous belt 3, and the first motor 1 drives the screw rod to do plane rotation motion so as to drive the nut assembly 41 to do linear motion.

The front end and the rear end of the large arm 9 and the front arm 12 are respectively provided with a mounting through hole, the nut component 41 is provided with a motor mounting hole, the output shaft of the second motor 10 sequentially penetrates through the mounting through holes of the large arm 9, the first thrust ball bearing 7 and the motor mounting hole to be mounted on the nut component 41, and the tail end of the second motor is locked and positioned through the first pre-tightening nut 5. Big arm 9 is connected with second motor 10 interference fit, and nut component 41 is connected with second motor 10 clearance fit, and first thrust ball bearing 7 supports between big arm 9 and nut component 41, and second motor 10 drive big arm 9 is the plane rotation around the second shaft, and first thrust ball bearing 7 makes big arm rotation more smooth and easy.

An output shaft of a third motor 11 sequentially penetrates through a mounting through hole of the large arm 9, a second thrust ball bearing 8 and a mounting hole of a front arm 12 to be mounted on the large arm 9, and the tail end of the third motor is locked and positioned through a second pre-tightening nut 6. Big arm 9 is connected with 11 clearance fit of third motor, and forearm 12 is connected with 11 interference fit of third motor, and second thrust ball bearing 8 supports between big arm 9 and forearm 12, and third motor 11 drive forearm 12 is the plane rotation around the third axle, and second thrust ball bearing 8 makes the forearm rotate more smoothly.

The fourth motor 13 and the end effector 14 are mounted on the front arm 12 through screws, an output shaft of the fourth motor 13 is connected with the end effector 14 through a second synchronous belt 15, the fourth motor 13 drives the end effector 14 to rotate around a central shaft of the body in a plane, and the fourth motor 13 is driven by the ball screw module 4 to move up and down.

First motor 1, second motor 10, third motor 11 and fourth motor 13 all adopt integrated low pressure servo motor, are connected with the PLC controller through the EtherCAT cable. The use of EtherCAT cable makes the use quantity that has reduced the arm cable, makes the arm volume reduce, has improved the motion range of robot, has increased system communication bandwidth. The PLC controller is a conventional one, and in this embodiment, the NIM2000 model is selected.

The integrated low-voltage servo motor is the prior art, and the model PMM6040 is selected in the embodiment. The PMM6040 integrated low-voltage servo motor is connected with a GF60A-L1-5-S-P2 speed reducer through a coupler, and the GF60A-L1-5-S-P2 speed reducer is used for motor speed reduction.

In this embodiment, adopt 1610 shape ball screw module, its active stroke is 200mm, moves the most weight of arm to the primary shaft through ball screw module for the arm lightweight, inertia is little, and the rate of motion is faster, and efficiency is higher.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A four-axis mechanical arm with a planar joint comprises a base and is characterized in that a first motor and a ball screw module are mounted on the base, the ball screw module comprises a screw rod and a nut assembly, the first motor is connected with the screw rod through a synchronous belt, and the first motor drives the screw rod to do planar rotary motion so as to drive the nut assembly to do linear motion; the nut component is provided with a second motor and a large arm, and the second motor drives the large arm to rotate around the second shaft in a plane manner; the front end of the big arm is provided with a third motor and a front arm, and the third motor drives the front arm to rotate around a third shaft in a plane manner; the front end of the forearm is provided with a fourth motor and an end effector, and the fourth motor drives the end effector to rotate in a plane; the first motor, the second motor, the third motor and the fourth motor are all integrated low-voltage servo motors and are connected with the PLC through EtherCAT cables.

2. The four-axis mechanical arm with the plane joint as claimed in claim 1, wherein the integrated low-voltage servo motor is connected with a planetary reducer.

3. The four-axis mechanical arm with the plane joint as claimed in claim 1 or 2, wherein the second motor output shaft passes through the large arm, is mounted on the nut component and is locked and positioned through a pre-tightening nut, and a first thrust ball bearing is arranged between the large arm and the nut component.

4. The four-axis mechanical arm with the plane joint as claimed in claim 1 or 2, wherein the third motor output shaft passes through the large arm, the front arm is mounted on the large arm and locked and positioned through a pretightening nut, and a second thrust ball bearing is arranged between the large arm and the front arm.

5. The four-axis planar articulated robotic arm of claim 1 or 2, wherein the fourth motor and the end effector are connected by a timing belt.

6. The four-axis mechanical arm with the plane joint as claimed in claim 1 or 2, wherein the ball screw module is 1610, and the effective stroke is 200 mm.