CN106609515A - Multi-connecting-rod variable-freedom-degree wood grasping machine provided with servo motors for driving - Google Patents

Abstract

A multi-link variable degree of freedom log grab driven by a servo motor, consisting of a base 1, an active rod 13, a first connecting rod 15, a first connecting piece 5, a fourth connecting rod 4, a large arm 2, and a wrist connection rod 6, the second connecting rod 22, the third connecting rod 26, the wrist 27, the claw 28, the servo drive device, the first locking device 23 and the second locking device 24; The pair 10 is connected on the base, and the first locking device 23 and the second locking device 24 are installed on the seventh rotating pair 16 and the eleventh rotating pair 19 respectively, and the servo driving device includes a first servo motor, and the active The rod 13 is connected to drive it to rotate; the first locking device 23 and the second locking device 24 are locked electromagnetically. The invention adopts the connecting rod transmission mechanism to replace the hydraulic mechanism, which solves the disadvantages of easy oil leakage and complicated mechanism of the hydraulic mechanism. The locking device on the revolving pair can adapt to different working conditions, and the number of motors used is less than the degree of freedom of the mechanism.

Description

A multi-link variable-degree-of-freedom log grab driven by a servo motor

technical field

The invention relates to the mechanical field, in particular to a multi-link variable-degree-of-freedom log grab driven by a servo motor.

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 log grabbers in timber harvesting, processing and handling operations. There are two types of log grabbers: mechanical and hydraulic. At present, most of the mechanical arms of log grabbers are driven by hydraulic pressure. Since 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 wood 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 machining accuracy, strict assembly requirements, difficult manufacturing, and high technical and difficult maintenance requirements during use. With the increase of the function of the log grab, its hydraulic system is more and more complicated, and the failure is more sudden and concealed. The mechanical log grab uses mechanical transmission parts to realize the action of grabbing wood, which has the advantages of being strong and durable, but the traditional single-degree-of-freedom mechanical log grab cannot complete complex actions, and its application range is very limited. The mechanical controllable mechanism electric grab For wooden 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 log grabs have been seen.

Contents of the invention

The object of the present invention is to provide a servo motor-driven connecting rod type variable-degree-of-freedom log grab, which overcomes the shortcomings of hydraulic system components such as high precision requirements, complex structure, and easy oil leakage, and overcomes the driving force of the 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 wood grabber, which overcomes the need for the same number of controls as the degree of freedom of the linkage mechanism to overcome the existing mechanical electric wood grab 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 multi-link variable degree of freedom log grab driven by a servo motor, which consists of a base 1, an active rod 13, a first connecting rod 15, a first connecting member 5, a fourth connecting rod Rod 4, big arm 2, wrist link 6, second link 22, third link 26, wrist 27, claw 28, servo drive, first locking device 23 and second locking device 24 The boom 2 is connected to the base through the first swivel pair 10, and the other end of the boom 2 is connected to the wrist link 6 through the third swivel pair 8; the active lever 13 is connected to the base 1 through the fifth swivel pair 12 connected, the other end is connected with the first connecting rod 15 through the sixth rotating pair 14, and the first connecting rod 15 is connected with the first connecting member 5 through the seventh rotating pair 16; the first connecting member 5 is connected through the eighth rotating pair 17 It is connected with the second connecting rod 22, and the other end of the second connecting rod 22 is connected with the wrist connecting rod 6 through the ninth rotating pair 7; the fourth connecting rod 4 is connected with the base 1 through the thirteenth rotating pair 20, and one end is connected through the The tenth rotating pair 18 is connected with the first connecting piece 5, the middle part is connected with the third connecting rod 26 through the eleventh rotating pair 19, and the other end of the third connecting rod 26 is connected with the boom 2 through the rotating pair 25; The first locking device 23 and the second locking device 24 are installed on the seventh rotating pair 16 and the eleventh rotating pair 19 respectively, and are locked in time according to different working conditions; the servo drive device includes a first servo motor, and the active The rod 13 is connected to drive it to rotate; the first locking device 23 and the second locking device 24 are locked electromagnetically.

A multi-link variable-degree-of-freedom wood grabber driven by a servo motor in the present 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, and improves the operating efficiency of the arm. Stability and reliability, no cumulative error, high precision; compact structure, high rigidity, large load-carrying capacity, low inertia, good dynamic performance, flexible and diverse arm motion 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 linkage mechanism of the log grabber, and the two-degree-of-freedom wood grabbing operation can be realized by using one active rod, which overcomes the need for the existing log grabber to be equipped with control motors with the same number of degrees of freedom as the linkage 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 log grab, such as high precision requirements, complex structure, easy oil leakage, poor reliability, and low transmission efficiency.

Description of drawings

Fig. 1 is a structural schematic diagram of a multi-link variable-degree-of-freedom log grab driven by a servo motor according to the present invention.

detailed description

A multi-link variable degree of freedom log grab driven by a servo motor, consisting of a base 1, an active rod 13, a first connecting rod 15, a first connecting piece 5, a fourth connecting rod 4, a large arm 2, and a wrist connection Rod 6, second connecting rod 22, third connecting rod 26, wrist 27, claw 28, servo drive device, first locking device 23 and second locking device 24; the base 1 is installed on a movable On the slewing platform; the boom 2 is connected to the base through the first swivel pair 10, and the other end of the boom 2 is connected to the wrist link 6 through the third swivel pair 8; It is connected with the base 1, and the other end is connected with the first connecting rod 15 through the sixth rotating pair 14, and the first connecting rod 15 is connected with the first connecting member 5 through the seventh rotating pair 16; the first connecting member 5 is connected through the eighth rotating pair The rotating pair 17 is connected to the second connecting rod 22, and the other end of the second connecting rod 22 is connected to the wrist connecting rod 6 through the ninth rotating pair 7; the fourth connecting rod 4 is connected to the base 1 through the thirteenth rotating pair 20 , one end is connected to the first connecting member 5 through the tenth rotating pair 18, the middle part is connected to the third connecting rod 26 through the eleventh rotating pair 19, and the other end of the third connecting rod 26 is connected to the boom 2 through the rotating pair 25 connection; the first locking device 23 and the second locking device 24 are installed on the seventh rotating pair 16 and the eleventh rotating pair 19 respectively, and are locked in time according to different working conditions; the servo drive device includes a first servo motor , is connected with the active rod 13 to drive it to rotate; the first locking device 23 and the second locking device 24 are locked by electromagnetic means.

In each working condition, when the lifting working condition, the first locking device 23 and the second locking device 24 are locked, the seventh rotating pair 16 and the eleventh rotating pair 19 lose their degrees of freedom, at this time the active rod 13 passes through The joint action of the first connecting rod 15, the third connecting rod 26, the first connecting member 5', the fourth connecting rod 4, the big arm 2 and the second connecting rod 22 lifts the wrist connecting rod 6 up and down. When the wrist link 6 is alone in the pitching condition, the first locking device 23 is opened, the seventh rotating pair 16 recovers the degree of freedom, the second locking device 24 is locked, and the eleventh rotating pair 19 loses the degree of freedom. At this time, the active lever 13 The wrist link 6 is pitched under the action of the first link 15 , the first link 5 and the second link 22 . The first locking device 7 and the second locking device 29 select to lock or open respectively according to different working conditions, and jointly complete the movements of the boom 2 lifting, the wrist link 6 and the wrist 27 pitching, etc., and realize the gripper 28. Grabbing operation, the first locking device 23 and the second locking device 24 can be locked by electromagnetic means, and the control is easy to realize.

Claims (1)

1. a kind of multi link driven with servomotor can variable freedom timber grab, it is characterised in that by base 1, driving lever 13rd, first connecting rod 15, the first connector 5, fourth link 4, large arm 2, wrist connecting rod 6, second connecting rod 22, third connecting rod 26, handss Wrist 27, paw 28, servo drive, the first locking device 23 and the second locking device 24 are constituted；The base 1 is installed On removable revolving dial；The large arm 2 rotates secondary 10 by first and is connected on base, and 2 other end of large arm passes through the 3rd Rotate secondary 8 to be connected with wrist connecting rod 6；The driving lever 13 rotates secondary 12 by the 5th and is connected with base 1, and the other end passes through the Six rotate secondary 14 is connected with first connecting rod 15, and first connecting rod 15 is rotated secondary 16 by the 7th and is connected with the first connector 5；Described A connection piece 5 is connected with second connecting rod 22 by eighth-turn dynamic secondary 17, and 22 other end of second connecting rod rotates secondary 7 and handss by the 9th Wrist connecting rod 6 connects；The fourth link 4 is rotated secondary 20 by the 13rd and is connected with base 1, and one end rotates secondary 18 by the tenth It is connected with the first connector 5, middle part is rotated secondary 19 by the 11st and is connected with third connecting rod 26,26 other end of third connecting rod It is connected with large arm 2 by rotating secondary 25；First locking device 23 and the second locking device 24 are separately mounted to the 7th turn Dynamic secondary 16 and the 11st rotates on secondary 19, is locked according to different operating modes in good time；Servo drive includes the first servomotor, with Driving lever 13 connects to drive which to rotate；First locking device 23 and the second locking device 24 are locked using electromagnetic mode.