CN106609519A - Variable-freedom-degree connecting rod mechanism - Google Patents

Abstract

A variable degree of freedom link mechanism, comprising a base 1, a boom lifting mechanism, a wrist link pitching mechanism, a servo drive device, a first locking device 5 and a second locking device 12; the boom lifting mechanism includes The boom 8, the fourth link 3 and the fifth link 6, the wrist link pitching mechanism includes the active link 16, the first link 18, the second link 21 and the third link 11, the first locking The device 5 and the second locking device 12 are installed on the eleventh rotating pair 4 and the eighth rotating pair 7 respectively, and can be locked in time according to different working conditions of the mechanism; the servo drive device includes a first servo motor and an active lever 16 connected to drive it to rotate; the first locking device 5 and the second locking device 12 are locked electromagnetically. The invention can realize the operation with two degrees of freedom by using only one active rod, reduces the number of motors used, and lowers the cost of the mechanism.

Description

A variable degree of freedom link mechanism

technical field

The invention relates to the mechanical field, in particular to a variable-degree-of-freedom link mechanism.

Background technique

In the past few years, due to the shortage of personnel in the labor market, labor costs have increased year by year, which has promoted the wide application of sugarcane grabbers in sugarcane harvesting and processing operations. There are two types of sugarcane grabbers: mechanical and hydraulic. At present, most of the mechanical arms of the cane grabber are hydraulically driven. Since the hydraulic transmission uses hydraulic oil as the medium for power transmission, there are the following problems: its starting performance is poor, and it is easy to cause Leakage occurs after internal components are worn, and the leaked hydraulic oil will pollute the environment and affect the quality of sugarcane raw materials; hydraulic oil is greatly affected by temperature, the overall efficiency is low, and sometimes there is noise and vibration. Sometimes there will be overheating, weak work and other phenomena; hydraulic components require high processing precision, strict assembly requirements, difficult manufacturing, and high technical maintenance requirements during use, which is relatively difficult. With the increase of the function of the sugarcane grabbing machine, its hydraulic system becomes more and more complicated, and the failure is more sudden and concealed. The mechanical cane grasping machine uses mechanical transmission parts to realize the cane grasping action, which has the advantages of being strong and durable, but the traditional single-degree-of-freedom mechanical cane grasping machine cannot complete complex actions, and its application range is very limited. The mechanical controllable mechanism electric grasping For sugarcane machines, the hydraulic transmission is replaced by a connecting rod mechanism. When the active rod is driven by a servo motor, it is easy to realize automation and numerical control, which solves some shortcomings of the hydraulic system, but it needs to be equipped with the same number of degrees of freedom as the connecting rod mechanism. The control motor is used to control the complex structure, which brings about the problems of mechanism weight, large motion inertia and high cost.

The variable degree of freedom mechanism adapts to the functional requirements of different stages by combining new topological structures. At present, there are few variable-degree-of-freedom mechanisms that can be applied to reality, and no variable-degree-of-freedom mechanisms that have been applied to sugarcane grabbing machines have been seen.

Contents of the invention

The purpose of the present invention is to provide a variable degree of freedom linkage mechanism applied to cane grabbing machines, which overcomes the shortcomings of hydraulic system components such as high precision requirements, complex structure, and easy oil leakage, and overcomes the drive mechanism of open chain structure. The disadvantage that the motors need to be installed at the joint position makes the number of controllable driving motors less than the degree of freedom of the linkage mechanism of the sugarcane grabbing machine, so as to overcome the existing mechanical electric cane grabbing mechanism that needs to be equipped with the same number of controls as the degree of freedom of the linkage mechanism The shortcomings of the motor to control, simplify the complexity of the structure, reduce the weight, inertia, volume and cost of the mechanism. In order to achieve the above object, the present invention provides a variable degree of freedom link mechanism, including a base 1, a boom lifting mechanism, a wrist link pitching mechanism, a servo drive device, a first locking device 5 and a second locking device 12; the base 1 is installed on a movable slewing platform; the boom lifting mechanism includes a boom 8, a fourth connecting rod 3 and a fifth connecting rod 6, and one end of the boom 8 connects with the sixth rotating pair 14 The base 1 is connected, and the other end is connected to the wrist link 10 through the ninth rotating pair 9; one end of the fourth connecting rod 3 is connected to the base 1 through the tenth rotating pair 2, and the other end is connected to the fifth connecting rod through the eleventh rotating pair 4. One end of the connecting rod 6 is connected, and the other end of the fifth connecting rod 6 is connected with the boom 8 through the seventh rotating pair 13; Three connecting rods 11, the sixth connecting rod 23 and the seventh connecting rod 25, one end of the active rod 16 is connected to the base 1 through the first rotating pair 15, and the other end is connected to one end of the first connecting rod 18 through the second rotating pair 17 , the other end of the first connecting rod 18 is connected to one end of the second connecting rod 21 through the third rotating pair 19, the other end of the second connecting rod 21 is connected to the wrist connecting rod 10 through the fifth rotating pair 22, and one end of the sixth connecting rod 23 is passed through The twelfth rotating pair 24 is connected to one end of the seventh connecting rod 25, the other end of the sixth connecting rod 23 is connected to the middle of the first connecting rod 18 through the thirteenth rotating pair 26, and the other end of the seventh connecting rod 25 is connected through the first rotating pair 15 is connected to the base 1; one end of the third connecting rod 11 is connected to the boom 8 through the eighth rotating pair 7, and the other end is connected to the second connecting rod 21 through the fourth rotating pair 20; the first locking device 5 and the second The locking device 12 is installed on the eleventh rotating pair 4 and the eighth rotating pair 7 respectively, and timely locks according to different working conditions of the mechanism; the servo drive device includes a first servo motor connected to the active rod 16 to drive its rotation; The first locking device 5 and the second locking device 12 are locked electromagnetically.

When a variable degree of freedom linkage mechanism described in the present invention is applied to the cane grasping operation, it is only necessary to connect the base 1 with the tire-type or crawler-type walking mechanism, and the wrist linkage 10 is connected with the wrist 27 and the claw 28 Just get up.

The invention adopts a controllable multi-rod closed-chain mechanism, which overcomes the disadvantage that the driving motors of the open-chain structure need to be installed at joint positions, improves the stability and reliability of the arm operation, has no cumulative error, and has high precision; the structure is compact, High rigidity, large bearing capacity, low inertia, good dynamic performance, flexible and diversified arm movement trajectory. A locking device is added to the linkage mechanism, and it is allowed to lock and release a specific rotating pair according to the different working conditions of the mechanism, which reduces the degree of freedom of the mechanism in a timely manner, and realizes the possibility of being used under the condition of fulfilling the expected requirements. The number of controlled driving motors is less than the degree of freedom of the connecting rod mechanism of the cane grabbing machine, and the two degrees of freedom cane grabbing operation can be realized by using one active rod, which overcomes the need for the existing cane grabbing machine to be equipped with control motors with the same number of degrees of freedom as the connecting rod mechanism. The shortcomings of control, simplify the complexity of the structure, reduce the weight, inertia, volume and cost of the mechanism, increase the controllability and stability of the mechanism, and improve work efficiency. At the same time, it also overcomes the shortcomings of the hydraulic system components of the hydraulic sugarcane grabbing machine, such as high precision requirements, complex structure, easy oil leakage, poor reliability, and low transmission efficiency.

Description of drawings

Fig. 1 is a schematic diagram of a variable degree of freedom link mechanism according to the present invention.

detailed description

A variable degree of freedom link mechanism, including a base 1, a boom elevating mechanism, a wrist link pitching mechanism, a servo drive device, a first locking device 5 and a second locking device 12; the base 1 is installed on a Move on the slewing platform; the boom lifting mechanism includes a boom 8, a fourth connecting rod 3 and a fifth connecting rod 6, one end of the boom 8 is connected to the base 1 through the sixth rotating pair 14, and the other end is connected through the ninth The rotating pair 9 is connected to the wrist link 10; one end of the fourth connecting rod 3 is connected to the base 1 through the tenth rotating pair 2, and the other end is connected to one end of the fifth connecting rod 6 through the eleventh rotating pair 4. The other end of the rod 6 is connected with the boom 8 through the seventh rotating pair 13; the wrist link pitching mechanism includes an active rod 16, a first link 18, a second link 21, a third link 11, and a sixth link 23 and the seventh connecting rod 25, one end of the active rod 16 is connected to the base 1 through the first rotating pair 15, the other end is connected to one end of the first connecting rod 18 through the second rotating pair 17, and the other end of the first connecting rod 18 is passed through The third rotating pair 19 is connected with one end of the second connecting rod 21, the other end of the second connecting rod 21 is connected with the wrist connecting rod 10 through the fifth rotating pair 22, and one end of the sixth connecting rod 23 is connected with the seventh connecting rod through the twelfth rotating pair 24. One end of the connecting rod 25 is connected, the other end of the sixth connecting rod 23 is connected to the middle part of the first connecting rod 18 through the thirteenth rotating pair 26, and the other end of the seventh connecting rod 25 is connected to the base 1 through the first rotating pair 15; One end of the connecting rod 11 is connected to the boom 8 through the eighth rotating pair 7, and the other end is connected to the second connecting rod 21 through the fourth rotating pair 20; the first locking device 5 and the second locking device 12 are respectively installed on the tenth On the first rotating pair 4 and the eighth rotating pair 7, timely locking is performed according to different working conditions of the mechanism; the servo drive device includes a first servo motor, which is connected with the active rod 16 to drive its rotation; the first locking device 5 and the second locking device The second locking device 12 is locked in an electromagnetic manner.

When a variable degree of freedom linkage mechanism described in the present invention is applied to the cane grasping operation, it is only necessary to connect the base 1 with the tire-type or crawler-type walking mechanism, and the wrist linkage 10 is connected with the wrist 27 and the claw 28 Just get up.

During work, when the boom 8 is raised and lowered, the first locking device 5 is opened, the eleventh turning pair 4 recovers the degree of freedom, the second locking device 12 is closed, and the eighth turning pair 7 loses the degree of freedom. At this time, the boom 8 lifts under the action of active lever 16. When the wrist link 10 is pitched alone, the second locking device 12 is opened, the eighth rotation joint 7 restores the degree of freedom, the first locking device 5 locks, the eleventh rotation joint 4 loses the degree of freedom, and the big arm 8 is relative to the base 1 The degree of freedom is lost, and now the wrist link is driven by the active rod 16 to pitch. During the whole cane grasping operation process, the first locking device 5 and the second locking device 12 select to lock or open respectively according to different working conditions, and jointly complete the lifting and telescoping of the boom, the wrist link 10 and the wrist 27. The motions such as the pitching of realizing hand claw 28 cane grasping operation. The first locking device 5 and the second locking device 12 can be locked by electromagnetic means, and the control is easy to realize.

Claims (1)

1. one kind can variable freedom linkage, it is characterised in that include：Base 1, large arm elevating mechanism, wrist connecting rod pitching machine Structure, servo drive, the first locking device 5 and the second locking device 12；The base 1 is arranged on removable revolving dial On；The large arm elevating mechanism includes large arm 8, the connecting rod 6 of fourth link 3 and the 5th, and the one end of the large arm 8 rotates by the 6th Secondary 14 are connected with base 1, and the other end rotates secondary 9 and is connected with wrist connecting rod 10 by the 9th；The one end of the fourth link 3 is by the Ten rotate secondary 2 is connected with base 1, and the other end rotates secondary 4 and is connected with the one end of the 5th connecting rod 6 by the 11st, and the 5th connecting rod 6 is another End rotates secondary 13 and is connected with large arm 8 by the 7th；The wrist connecting rod luffing mechanism include driving lever 16, first connecting rod 18, the Two connecting rods 21 and third connecting rod 11, six-bar linkage 23 and seven-link assembly 25, one end of the driving lever 16 rotates secondary 15 by first It is connected with base 1, the other end rotates secondary 17 and is connected with the one end of first connecting rod 18 by second, the other end of first connecting rod 18 passes through the Three rotate secondary 19 is connected with the one end of second connecting rod 21, and the other end of second connecting rod 21 rotates secondary 22 and connects with wrist connecting rod 10 by the 5th Connect, the one end of six-bar linkage 23 is connected by the 12nd rotation secondary 24 with the one end of seven-link assembly 25, the other end of six-bar linkage 23 passes through 13rd rotates secondary 26 is connected with the middle part of first connecting rod 18, and the other end of seven-link assembly 25 rotates secondary 15 connect base 1 by first； The one end of the third connecting rod 11 is connected by eighth-turn dynamic secondary 7 with large arm 8, and the other end rotates secondary 20 and second connecting rod by the 4th 21 connections；First locking device 5 and the second locking device 12 are separately mounted in the 11st rotation secondary 4 and eighth-turn dynamic secondary 7, are pressed Locked in good time according to the different operating mode of mechanism；Servo drive is connected to drive including the first servomotor with driving lever 16 Its rotation；First locking device 5 and the second locking device 12 are locked using electromagnetic mode.