CN118163136A

CN118163136A - Multifunctional mechanical gripper

Info

Publication number: CN118163136A
Application number: CN202211588601.XA
Authority: CN
Inventors: 张新
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-12-11
Filing date: 2022-12-11
Publication date: 2024-06-11

Abstract

In an automatic material processing system, materials are required to be selected, classified and split, most of the functions of the paw in the current automation field are single, and the paw can only process fixed or less-specification materials and cannot adapt to the situation that the size and the shape of the product are greatly changed. Aiming at the situation, the product adopts a telescopic straw solution with a plurality of independent controls to solve the problems: the gripper is provided with a plurality of straws, each straw can independently control the up-and-down motion of the straw, the end of each straw is provided with a sucker, a straw group consisting of a plurality of independent straws is formed, and the number and the length of the extended straws can be controlled according to the size and the shape of the materials to adapt to the surfaces of the materials, so that the problems are solved. The independent control of the suction pipes can adopt two schemes, namely, an electromagnetic clutch controller is adopted to realize the independent control of a single suction pipe; and secondly, independent control of a single straw is realized by adopting a screw motor.

Description

Multifunctional mechanical gripper

Technical Field

The mechanical gripper is used for gripping materials and can adapt to the sizes and different shapes of the materials.

Background

In an automatic material handling system, materials are required to be sorted, classified and split, however, we often face various materials including different sizes, different shapes and different materials, one set of mechanical claws is difficult to adapt to different materials, that is, one set of mechanical claws can only handle materials in a specific range, the automation degree of the material handling system is greatly affected due to the limitation of the function, and meanwhile, if multiple sets of mechanical claws are required to handle multiple materials, the material handling system becomes complex; through thinking, the self provides a brand new scheme, through disposing a plurality of straws, each straw can independently control the up-and-down motion of the straw, and the sucker is disposed at the end of the straw, so that a straw group consisting of a plurality of independent straws is formed, the straw group can be disposed according to the size and the quantity of materials, the extending length of the straw can be adjusted according to the shape of the surface of the materials, and the fit surface with the surface of the materials is formed, so that the grabbing problems of different sizes and different shapes of the materials are solved.

Disclosure of Invention

The up-and-down movement of the suction pipe can be achieved in two ways, one is achieved through electromagnetic clutch brake control, and the other is achieved through screw movement, and the two ways are respectively described below.

Description of the drawings:

FIG. 1 is a suction tube design employing an electromagnetic clutch brake scheme;

FIG. 2 is a general design of a pawl employing an electromagnetic clutch brake scheme;

FIG. 3 is a layout of a drive motor employing an electromagnetic clutch brake scheme;

FIG. 4 is a design drawing of an electromagnetic clutch controller employing an electromagnetic clutch brake scheme;

FIG. 5 is a high and low schematic view of a mechanical gripper employing an electromagnetic clutch brake scheme;

FIG. 6 is a drawing of a pipette design employing a screw drive scheme;

FIG. 7 is a general design of a gripper employing a screw drive scheme;

Suction pipe (electromagnetic clutch brake control): referring to fig. 1, the suction pipe is a circular through pipe and is hollow, meanwhile, a rack 2 is designed on the suction pipe and is used for driving the suction pipe to move in cooperation with a gear, a middle hollow hole is used for inserting an air pipe 3, a suction cup 4 is designed at the end of the suction pipe and is used for grabbing materials, the suction cup and the end of the suction pipe are connected into a ball free pair, and the suction cup can freely deflect at a certain angle; the ball free pair mainly comprises an air pipe joint 5, a ball body 6 and a pressing plate 7, wherein the sucking disc and the air pipe are respectively connected to two ends of the ball body, and if the surface of a material is uneven, such as an inclined plane, the sucking disc can be influenced by the acting force of the material, the state of the sucking disc can be automatically adjusted, and the sucking disc is attached to the surface of the material.

Mechanical gripper (electromagnetic clutch brake control): referring to fig. 2, the mechanical gripper mainly comprises a suction pipe 1, upper and lower bases 7 and 2, an electromagnetic clutch brake group 3 (comprising gears), a motor mounting plate 4, a motor 5, a base connecting column 6, a vacuum generator 8, an air pipe 9, a gripper connecting seat 10, a driving shaft 11, a driving chain wheel group 12 and the like;

The paw is provided with 24 straws which move up and down in the guide holes of the upper base and the lower base, the top surface of the lower base is provided with 24 groups of electromagnetic clutch brake groups, each group is responsible for driving/braking one straw, 4 rows of 24 straws are provided, 6 straws are provided in each row, the straws are driven by one driving shaft 11, and the electromagnetic clutch brake groups in each row are fixed through shaft sleeves; the drive shaft sprocket 12 is installed in the middle of the drive shaft, driven by a motor 5 (see fig. 3) installed on the motor installation plate 4; the top surface of the upper base is provided with a vacuum generator, each suction pipe corresponds to one vacuum generator 8 and is connected to the inside of the suction pipe through an air pipe 9, and the suction pipes are always communicated with the suction disc; the upper base and the lower base are connected through a base connecting column 6 and are positioned and fixed; the entire gripper is mounted to the robot via the gripper attachment socket 10.

Electromagnetic clutch brake group: referring to fig. 4, the electromagnetic clutch brake set mainly consists of two parts, one part is an electromagnetic clutch, the other part is an electromagnetic brake, the electromagnetic clutch is mainly used for driving the gear 5 to rotate, and the electromagnetic brake is mainly used for braking the gear 5 to prevent the gear from rotating under the condition that the clutch is powered off; the electromagnetic clutch mainly comprises a frame 3, an electromagnetic coil 4, a friction plate 1 and a disc reed 2, wherein the frame is connected to a driving shaft 8 in a key way and rotates along with the rotation of the shaft, a gear 5 is connected with the driving shaft through a bearing, the disc reed and the friction plate are separated in a power-off state, the gear cannot rotate along with the rotation of the shaft, and when the power is on, the disc reed is close to the friction plate and the friction drives the gear to rotate; the electromagnetic brake consists of an electromagnetic coil 9, a frame 10, a friction plate 6 and a disc reed 7, wherein the frame 10 is arranged on the lower base and is not connected with a driving shaft, the driving shaft does not rotate when rotating, and the coil is arranged on the frame; in the power-off state, the disc reed and the friction plate are separated, the gear can rotate, and when the power is on, the disc reed is close to the friction plate to lock the gear;

The working principle of the electromagnetic clutch brake set is as follows: the clutch and the brake work cooperatively, when the clutch is electrified, the driving shaft drives the gear to rotate, and at the moment, the brake is powered off; when the clutch is powered off, the gear can rotate under the action of external force (such as the gravity of the suction pipe) so as to be unfavorable for locking the suction pipe, and therefore, an additional brake is needed for braking and locking the gear, and therefore, when the clutch is powered on, the brake is needed for locking the gear.

Mechanical gripper operation flow (electromagnetic clutch brake control): the paw is arranged on the robot (a four-axis or 6-axis robot) through the connecting seat, and is combined with the vision system to carry out material grabbing operation; initially, the gripper straw is in a high position (see fig. 5), the straw being locked by the brake; the vision system shoots and acquires information such as the position, the shape, the size, the distance and the like of the materials, the control system distributes the straws (the number is a few) according to the material information, and the running distance (defaults to be the maximum) of each straw is determined; the paw moves to the upper part of the material under the control of the control system, the corresponding straw brake is powered off, the clutch is powered on, the motor drives the driving shaft to drive the gear to rotate, the straw is stretched out to a proper position (at the moment, the straw is in a low-position state), then the clutch is powered off, and the brake is powered on to lock the straw; reaching above the material, establishing vacuum by a vacuum system, making the claws approach to the material, and grabbing the material; then the paw rises and moves to the upper part of the material release, slightly descends, the vacuum is lost, and the material falls to the corresponding position to finish a material grabbing action;

Then the paw returns to prepare the grabbing of the next material; synchronously shooting by a vision system, transmitting material information to a control system, distributing suction pipes by the control system according to the materials to be grabbed, wherein the suction pipes which need to be stretched out extend out (the control is the same as the previous one), if the suction pipe used for grabbing the previous material is too far to be retracted, powering on a corresponding clutch, powering off a brake, reversing a driving shaft by a motor, lifting the stretched suction pipe to a high position, powering off the clutch after the suction pipe is in place, and powering on the brake to lock the suction pipe; because one driving shaft drives a plurality of suction pipes, if the suction pipe corresponding to one driving shaft ascends and descends, the suction pipe ascends and descends or vice versa according to the requirement; then the gripping of the materials after the gripper is in place is the same as before.

Straw (screw drive): the suction pipe driven by the screw is different from the suction pipe driven by the electromagnetic clutch, and is divided into two parts, wherein one part is the screw and the other part is the suction pipe, and the upper end of the suction pipe is connected with the end part of the screw through a self-aligning bearing; the suction pipe is still a round pipe and hollow, is used for the gas pipe 5, is connected with an external gas pipe through the gas pipe joint 3, and the lower end is connected with the suction cup 7 through a ball connection pair (same as the former) 6;

The connection of the suction pipe and the screw rod is connected by adopting a self-aligning bearing, and mainly comprises an end shaft 10, a self-aligning bearing 9 and an end cover 8; the end shaft 10 is fixed to the end of the screw rod through threads, the self-aligning bearing is arranged on the end shaft, and the suction pipe is connected with the outer ring of the self-aligning bearing through an end cover.

Mechanical gripper (screw drive): referring to fig. 7, the mechanical gripper mainly comprises a suction pipe 1, an upper base 9, a lower base 2, a vacuum generator 3, an air pipe 4, a screw 5, a screw guide sleeve 6, a motor mounting plate 7, a motor 8, a gripper connecting seat 10 and the like;

36 straws are arranged in total, move up and down in the guide hole of the lower base 2, the screw rod 5 moves between the screw rod guide sleeve 6 and the guide hole of the upper base 9, the top surface of the lower base is provided with 36 vacuum generators, each straw corresponds to one vacuum generator 3 and is connected to the interior of the straw through the air pipe 4, and the suction pipes are led to the suction disc all the time; the number of screw driving motors 8 is 36, each motor drives one screw, namely each suction pipe is driven by one motor; the motor is arranged on the motor mounting plate 7 and is positioned between the upper base and the screw guide sleeve; the whole paw is mounted on the robot through a paw connecting seat 10;

along with the driving of the screw motor, the screw moves up and down to drive the suction pipe to move up and down; the motor stops the band-type brake, and the suction pipe stops moving and is locked.

Mechanical gripper operation flow (screw drive): the paw is arranged on the robot (a four-axis or 6-axis robot) through the connecting seat, and is combined with the vision system to carry out material grabbing operation; initially, the paw straw is in a high state, and the straw is locked by a motor; the vision system shoots and acquires information such as the position, the shape, the size, the distance and the like of the materials, the control system distributes the straws (the number is a few) according to the material information, and the running distance (defaults to be the maximum) of each straw is determined; the gripper moves to the upper part of the material under the control of the control system, and the corresponding suction pipes extend to the position (at the moment, the suction pipes are in a low-position state), so that the vacuum system establishes vacuum along with the gripper reaching the upper part of the material, and the gripper approaches the material to grasp the material; then the paw rises and moves to the upper part of the material release, slightly descends, the vacuum is lost, and the material falls to the corresponding position to finish a material grabbing action;

Then the paw returns to prepare the grabbing of the next material; synchronously shooting by a vision system, transmitting material information to a control system, and distributing suction pipes by the control system according to the material to be grabbed, wherein the suction pipes which need to be stretched out extend out (control is the same as the former), if the suction pipes used for grabbing the former material need to be retracted, a screw motor turns over, a screw is driven to ascend, and the stretched suction pipes are lifted to a high position and braked to lock the suction pipes; then the gripping of the materials after the gripper is in place is the same as before.

Claims

1. A mechanical gripper for grabbing materials is widely used for sorting, classifying and distributing materials with different sizes and shapes.

2. According to claim 1, the gripper is composed of a plurality of independently telescopic straws, and the gripper can control the extending quantity and the extending length of the straws according to the size and the shape of materials to grasp the materials.

3. According to claim 1, the vacuum chuck is arranged at the end of the suction pipe, and the end of the suction pipe is connected with the suction pipe by adopting a ball free pair, so that the suction pipe is flexible to rotate, better fits the surface of the material and facilitates the grabbing of the material.

4. According to claim 1, the suction pipe moves up and down in a first mode: the motion and stop of the gear are controlled by adopting a mode of combining a miniature electromagnetic clutch, a gear and a miniature electromagnetic brake, and the gear is matched with a rack on the suction pipe to drive the suction pipe to move up and down and stop.

5. According to claim 1, the straw moves up and down in a second mode: the miniature screw mechanism is adopted, the suction pipe is connected to the screw rod, and the screw rod is driven to move up and down and stop through the motor, so that the suction pipe is driven to move up and down and stop.