Showing papers on "Pulley published in 2015"

Measurement of the cable-pulley Coulomb and viscous friction for a cable-driven surgical robotic system

Abstract: In this paper we present experimentally obtained cable-pulley Coulomb and viscous friction for cable-driven surgical robotic systems including the RAVEN II surgical robotic research platform. In the study of controlling cable-driven systems a simple mathematical model which does not capture physical behavior well is often employed. Even though control of such systems is achievable without an accurate model, fully understanding the behavior of the system will potentially realize more robust control. A surgical robot is one of the systems that often relies on cables as an actuation method as well as pulleys to guide them. Systems with such structure encounter frictional force related to conditions of cable and pulley such as cable velocity, tension, type and number of pulley, and angle of cable wrapping around pulley. Using a couple of test platforms that incorporate cable, pulleys, and other experimental conditions corresponding to the RAVEN II system, it is shown that cable-pulley friction is function of tension, wrap angle, and number of pulleys and not of magnitude of cable velocity.

Design, identification and experimental testing of a light-weight flexible-joint arm for aerial physical interaction

Abstract: In this paper we introduce the design of a light-weight novel flexible-joint arm for light-weight unmanned aerial vehicles (UAVs), which can be used both for safe physical interaction with the environment and it represents also a preliminary step in the direction of performing quick motions for tasks such as hammering or throwing. The actuator consists of an active pulley driven by a rotational servo motor, a passive pulley which is attached to a rigid link, and the elastic connections (springs) between these two pulleys. We identify the physical parameters of the system, and use an optimal control strategy to maximize its velocity by taking advantage of elastic components. The prototype can be extended to a light-weight variable stiffness actuator. The flexible-joint arm is applied on a quadrotor, to be used in aerial physical interaction tasks, which implies that the elastic components can also be used for stable interaction absorbing the interactive disturbances which might damage the flying system and its hardware. The design is validated through several experiments, and future developments are discussed in the paper.

Pulley friction compensation for winch-integrated cable force measurement and verification on a cable-driven parallel robot

Abstract: In a cable-driven parallel robot, elastic cables are used to manipulate the end effector within the workspace. Cable force measurement is necessary for several control algorithms like cable force control, contact control, or load identification. The cable force sensor can be placed directly at the connection point on the platform or somewhere along the cable using pulleys. The pulleys between the force sensor and the platform disturb the force measurement accuracy due to friction. This paper deals with modeling and compensation of the friction. The friction behavior in the drive train with focus on the effects of the pulleys is non-trivial, as the cable movement consists of microscopic and macroscopic movements and standstills. Friction models from Coulomb and Dahl are adapted to deal with the pulley friction. The experimental evaluation showed an improvement of 70% with respect to the uncompensated case.

Under-actuated prosthetic hand capable of reproducing hand grasping function

Abstract: The invention discloses an under-actuated prosthetic hand capable of reproducing a hand grasping function; the under-actuated prosthetic hand is provided with an interphalangeal drive mechanism and a thumb drive mechanism in a palm; finger bodies take pulleys as main parts, and transmission mechanisms arranged in fingers are sequentially and alternately wound on all the pulleys of the fingers by steel wire ropes; joints in the fingers are in flexible coupling by elastic components; the interphalangeal drive mechanism adopts two motors to drive four fingers and multiple degrees of freedom of the fingers in a synergetic way; a thumb body takes a pulley as a main part, the transmission mechanisms in the finger bodies take transmission ropes as transmission mediums, the interphalangeal drive mechanism adopts a gear component for transmission matching, and the four degrees of freedom of the thumb can be controlled by two motors. After the under-actuated prosthetic hand is adopted, self-adaptive grasping of various objects can be accurately completed, and the rich grasping operation function of a human hand can be reproduced; the under-actuated prosthetic hand has the characteristics of being compact in structure, smaller in size, lighter in weight, convenient to control, accurate in grasping action, and the like.

Domestic garbage treatment device

Abstract: The utility model discloses a domestic garbage treatment device comprising a feed hopper, a fan, a communicating pipe, a heating tank, a cutting knife, a rotating shaft, a material guide inclined plate, a driven belt pulley, a belt, a crushing bin, a driving belt pulley, a cutting motor and a tank body, wherein the feed hopper is arranged at the upper end of the tank body, the fan is arranged on the left side of the feed hopper, the communicating pipe is arranged on the left side of the fan, the heating tank is arranged at the lower end of the communicating pipe, the crushing bin is arranged below the feed hopper, the rotating shaft is arranged in the crushing bin, the cutting knife is arranged on the rotating shaft, the driven belt pulley is arranged at the right end of the rotating shaft, the belt is arranged on the driven belt pulley, the upper end of the belt is connected with the driving belt pulley, the cutting motor is arranged at the left end of the driving belt pulley, and the material guide inclined plate is arranged at the lower end of the rotating shaft. According to the domestic garbage treatment device disclosed by the utility model, hot air in the heating tank is blown into the tank body by virtue of the fan so as to ensure that air in the device circulates; and in addition, the hot air can be used for removing moisture in the device, so that bacteria can be prevented from breeding in the device, and thus the safety of compressed materials can be ensured.

Functional trainer exercise machine

Abstract: An exercise machine has at least one hollow column rotationally mounted between upper and base members of a frame. A pulley carriage is mounted inside the column in engagement with an internal track for travel up and down the track, and a cable linked to an exercise resistance extends through the pulley carriage before terminating at a cable pull attachable to a selected user engagement accessory. A pulley cover pivoted to the carriage extends partially out of a column opening and extends over one or more pulleys mounted in the pulley carriage.

Portable elliptical exercise machine

Abstract: An exercise apparatus having a pulley, a pair of stabilizing assemblies each configured to couple a front portion of a respective pedal element to each side of the pulley, a looped belt configured to couple the pulley to a resistance assembly, a tension stabilizer configured to maintain a tension of the looped belt on the pulley, and the resistance assembly configured to assert an adjustable resistance to the pedal elements through the looped belt, where the resistance is adjusted by changing a distance between a flywheel element and a corresponding magnetic plate element of the resistance assembly, the magnetic plate asserting a magnetic force over the distance on the flywheel element and the looped belt looping around a co-rotating extension from the flywheel element.

Shooting bow with pulleys

Abstract: A shooting bow includes pulleys, a string latch, bow riser, barrel, first limb, second limb, a first cam, and a second cam. The bow riser is enjoined with the barrel. The first and second limbs extend from the bow riser. The first and second cams are pivotally retained on the first and second limbs. A bowstring is retained by the first and second cams. A first pulley and a second pulley are retained on the barrel. Both cams have a string track and a cable track. One end of the string is coupled to the first cam and the other end is coupled to the second cam. As for both cables, one end is coupled to the first cam, the middle of the cable travels around a pulley or track, and the other end is coupled to the first limb, first cam axle or back to the cam.

Design Of A Material Handling Equipment: Belt Conveyor System For Crushed Limestone Using 3 Roll Idlers

Abstract: In the process or manufacturing industry, raw materials and products need to be transported from one manufacturing stage to another. Material handling equipment are designed such that they facilitate easy, cheap, fast and safe loading and unloading with least human interference. For instance, belt conveyor system can be employed for easy handling of materials beyond human capacity in terms of weight and height. This paper discusses the design calculations and considerations of belt conveyor system for limestone using 3 rolls idlers, in terms of size, length, capacity and speed, roller diameter, power and tension, idler spacing, type of drive unit, diameter, location and arrangement of pulley, angle and axis of rotation, control mode, intended application, product to be handled as well as its maximum loading capacity in order ensure fast, continuous and efficient movement of crushed limestone while avoiding halt or fatalities during loading and unloading. The successful completion of this research work has generated design data for industrial uses in the development of an automated belt conveyor system which is fast, safe and efficient.

Design of two stage planetary gear train for high reduction ratio

Abstract: Planetary Gear Trains are extensively used for the power transmission and are the most critical component. Planetary gearboxes are used frequently to match the inertias, lower the motor speed, boost the torque, and at the same time provide a sturdy mechanical interface for pulleys, cams, drums and other mechanical components. This paper presents the advantages of planetary gear systems over other, consideration to be given while determining the reduction ratios of gear box, minimum and maximum reductions per stage of planetary gear pairs. Also the case study to determine the reduction ratio of two stage gear box is discussed. The comparison of planetary gear system over helical gears systems is done on the basis of volume, weight and torque density

Electric vehicle charging system

Abstract: A cable management system for an electric vehicle (EV) charging station comprises an upstanding enclosure having a cable opening though which an EV charging cable can be pulled for extension. The EV charging cable is provided at a free end thereof with an EV charging connector for connection with an EV charging socket of an EV. The EV charging cable is provided at an opposed fixed end thereof with an electric connector for connection with a mating connector mounted inside the enclosure. A fixed pulley is mounted within the upstanding enclosure for rotation about a first axis normal to an upstanding axis of the enclosure. The system further comprises a mobile pulley rotatable about a second axis parallel to the first axis. The mobile pulley is vertically translatable within a guiding structure mounted inside the upstanding enclosure for movement towards and away from the fixed pulley. The fixed pulley is mounted at a higher elevation than the mobile pulley. The EV charging cable extends over the fixed pulley and the mobile pulley between its opposed free and fixed ends. The mobile pulley is moveable against gravity from a lowered position to a raised position by the application of a sufficient pulling force at the free distal end of the EV charging cable. The mobile pulley returns at least partly under gravity to its lowered position upon release of the EV charging cable, thereby automatically retracting the cable inside the upstanding enclosure.

Continuous multi-joint mechanical arm device

Abstract: The invention provides a continuous multi-joint mechanical arm device. The continuous multi-joint mechanical arm device comprises two parts, i.e. a pedestal and a mechanical arm, wherein the pedestal part consists of a driving part, a lower motor fixing plate, an upper motor fixing plate, a lower pulley plate, an upper pulley plate, a pulley component and connecting rods; the connecting rods are arranged among the plates; the driving part comprises a motor, a coupler and a screw rod; the mechanical arm consists of a joint with two freedom degrees and a plurality of joint backbones; each joint and each joint backbone are of the same structure; the driving part is arranged in the pedestal of the mechanical arm device; the other end of the driving device is connected with a rope; the other end of the rope is fixed to joint plates of the joint backbones. The mechanical arm provided by the invention is flexible in structure, so that the continuous multi-joint mechanical arm device is good in obstacle avoidance ability; the mechanical arm is applied in a narrow and complex work space environment, such as ruins rescuing and mechanical fitting assembly, so that the continuous multi-joint mechanical arm device is wide in application range.

Punch press mechanical arm

Abstract: The utility model relates to the technical field of mechanical arms, in particular to a punch press mechanical arm. The punch press mechanical arm comprises a rack, a lifting seat, a lifting driving device, a rotary seat, a rotary driving device, a telescopic device, a correction swing arm and suction cups. The telescopic device comprises a sliding table, a telescopic arm, a first synchronous pulley transmission mechanism and a telescopic driving motor. The first synchronous pulley transmission mechanism comprises two synchronous pulleys and a synchronous belt. The output end of the telescopic driving motor is in driving connection with the synchronous pulley located at the rear end of the sliding table. One section of the synchronous belt is fixedly connected to the telescopic arm. Sliding rails are arranged on the two sides of the sliding table respectively. The telescopic arm is connected with the sliding rails in a sliding mode. According to the punch press mechanical arm, a workpiece can be automatically taken and placed and driven to ascend, descend, rotate, stretch, retract, move horizontally and the like, work efficiency is high, safety and reliability are achieved, accuracy is high, the sliding rails of the sliding table are externally arranged, the size of the sliding table and the size of the whole mechanical arm can be reduced, the rigidity and the strength of the sliding table are improved, and the accuracy of the sliding table is improved.

Coin sorting device

Abstract: The utility model relates to a coin sorting device, the funnel support on its structure includes the base and sets gradually it, taeniola wheel support, big band pulley support, left slide bracket, right slide bracket, the funnel is installed on the funnel support, and the motor drives staff, little band pulley, macroaxis, big band pulley, the motion of motion belt, and the funnel below is placed in to motion belt level, an inclined plane slide is settled on left and right slide bracket, and the left end of inclined plane slide is the hourglass hopper -shaped who keeps flat, extends to big band pulley below right, extends a flat board left, and the upper surface of plate part has 4 tracks, sets gradually the trapezoidal hole of three variation in size on every track, and slide below in inclined plane sets up a drawer that has 3 grids, and every grid is corresponding with the trapezoidal hole of variation in size The utility model relates to an use high -efficient, easy and simple to handle, as to realize the letter sorting of automatic coin device

Universal cable laying pulley

Abstract: The utility model belongs to the field of power grid cable laying construction, and particularly relates to a universal cable laying pulley The universal cable laying pulley comprises more than three pulley wheel units and a fixing seat for fixedly connecting the pulley wheel units to a bracket Each pulley wheel unit is composed of a roller base and a roller The roller bases of the pulley wheel units are connected end to end to form a closed ring structure The surfaces of the rollers face inward to form the inner ring surface of the closed loop structure, and the inner ring surface forms a channel for a cable to run through The axes of rotation of the rollers are arranged to be perpendicular to the running direction of the cable The roller base of at least one pulley wheel unit and the roller base of the adjacent pulley wheel unit form an opening-closing Haver or articulated fit relationship at the joint, and the opening and closing ends of the fit relationship are provided with an inlet and an outlet for cable picking and placing The drop damage phenomenon in the existing cable laying process can be avoided while the cable towing resistance is effectively reduced The laying reliability and the operation efficiency are effectively improved

Electric rotating welding fixture

Abstract: The invention discloses an electric rotating welding fixture. The electric rotating welding fixture comprises a base and a clamping base. A rotating shaft base is arranged on the base, a supporting plate connected with a rotating shaft is installed on the rotating shaft base, a rotating motor is arranged on one side of the rotating shaft base, two belt pulleys are in matched transmission through a belt, the upper surface of a clamping plate is provided with moving grooves transversely and vertically, and clamping blocks driven by piston rods of moving air cylinders are installed in the moving grooves. The belt pulley of the rotating motor drives the belt pulley on the rotating shaft to rotate through the belt, a product is placed on the supporting plate and then fixed through the clamping base matched with the pulleys, a welding head only needs to be assigned to one point of the product, the rotating motor rotates to drive the supporting plate to rotate to achieve welding, the welding head does not need to rotate, and therefore the problems that because the welding head rotates, welding is uneven and welding efficiency is low are solved, and the welding efficiency and welding quality of the product are greatly improved.

Mute drilling method and mute electric drill

Abstract: The invention relates to a mute drilling method and a mute electric drill, and aims at solving the problem that the noise of the existing electric drill is large. Two permanent magnet motors are oppositely arranged on a horizontal machine seat in a left and right balance mode; the two permanent magnet motors commonly drive a middle shaft with a drill chuck to realize symmetrical phase angles, and collision is generated in the vibration direction of a motor; collision waves commonly act on the machine body so that waveforms are offset to disappear; the middle shaft is arranged in the middle of the horizontal machine seat by a bearing block; the two permanent magnet motors respectively drive driven synchronous pulleys arranged on the middle shaft by a driving synchronous pulley and a synchronous driving belt; left and right stators of the left and right permanent magnet motors are in left and right symmetric distribution; left and right rotors of the left and right permanent magnet motors are in left and right symmetric distribution; a sliding rod and a screw rod which are in left and right symmetric distribution are in axial sliding fit with two sides of the middle shaft on the horizontal machine seat by left and right sliding fit sleeves which are parallel with the middle shaft; an end plate with a middle hole is fixedly mounted on the front ends of the sliding rod and the screw rod commonly; an internal thread handle sleeve is matched with the lower part of the screw rod by threads; a support spring is in sliding fit and is sleeved with the screw rod between the internal thread handle sleeve and the horizontal machine seat or between the sliding fit sleeves. The invention has the advantages that the torque is large, the drilling speed is rapid, the adaptive capacity is strong, the use is convenient, and the mute effect is good.

Automatic sweeping robot for surface dust of photovoltaic solar cell panel

Abstract: The utility model provides an automatic sweeping robot for a surface dust of a photovoltaic solar cell panel. The automatic sweeping robot is that a belt motor (2) is mounted at the lower end of a belt bracket (8); a belt brush (3) passes through the belt motor (2) and a belt pulley (24) to be mounted on the belt bracket (8); a winch (13) is mounted at the upper end of a vertical moving bracket (12); one end of a steel wire rope (9) is connected with the belt bracket (8) and while the other end of the steel wire rope (9) is connected with the winch (13); a lifting motor (14) is mounted at the upper of a horizontal moving bracket (18); a vertical moving guide rail (10) is mounted at the front end of the horizontal moving bracket (18); a lifting lead screw (16) and a lifting nut seat (7) form a lead screw nut pair which is driven by a lifting motor 14; a horizontal moving driving motor (21) is mounted on a car body (23); a horizontal moving lead screw (20) and a horizontal moving nut seat (19) form another lead screw nut pair which is driven by the horizontal moving driving motor (21).

Six-freedom-degree bionic mechanical arm based on pneumatic muscle

Abstract: The invention discloses a six-freedom-degree bionic mechanical arm based on pneumatic muscle. The six-freedom-degree bionic mechanical arm comprises a frame, a shoulder joint, an elbow joint, a wrist joint and a mechanical palm. The shoulder joint, the elbow joint, the wrist joint and the mechanical palm are sequentially connected and fixed to the frame. Moreover, the pneumatic muscle serves as a driver. Pulley components are used for achieving swinging and rotation of the joints. The six-freedom-degree bionic mechanical arm is small in size, high in flexibility and high in bionic degree.

Double-screw synchronous lifting mechanism

Abstract: The invention discloses a double-screw synchronous lifting mechanism which comprises a base, a top plate, a first screw rod, a second screw rod, a lifting platform assembly, a rotary drive assembly, a first driven synchronous pulley, a second driven synchronous pulley and a synchronous belt. The top plate is arranged above the base. One end of the first screw rod and one end of the second screw rod are arranged on the base in a rotatable mode, the other end of the first screw rod and the other end of the second screw rod are arranged on the top plate in a rotatable mode, and the first screw rod and the second screw rod are parallel. The lifting platform assembly is matched with the first screw rod and the second screw rod in a threaded mode and located between the base and the top plate. The rotary drive assembly is arranged on the base or the top plate. A driving synchronous pulley is arranged on an output shaft of the rotary drive assembly. The first driven synchronous pulley is arranged on the first screw rod and identical with the driving synchronous pulley. The second driven synchronous pulley is arranged on the second screw rod and identical with the driving synchronous pulley. The synchronous belt enables the driving synchronous pulley to be connected with the first driven synchronous pulley and the second driven synchronous pulley. The double-screw synchronous lifting mechanism can effectively lower the stress of each screw rod, and the ascending and descending process of the lifting platform can be more stable.

Vehicle control device

Abstract: PROBLEM TO BE SOLVED: To prevent longitudinal-slide shift control from being executed in a state in which an input torque is not less than a predetermined value, thereby improving the durability of a belt and a pulley and improving responsiveness of accelerator operation after execution of the longitudinal-slide shift control.SOLUTION: An initial irregularity learning control is executed whenever learning conditions are satisfied with views of absorbing initial irregularities such as manufacturing errors and irregularities in constituent elements of a second clutch CL2. A total number of times of learning is counted, and if the total number of times of learning for the initial irregularity learning control reaches a predetermined number (five, for example), it is determined that the initial irregularity learning control converges. On condition of this learning control convergence, a so-called longitudinal-slide shift control is executed for returning a belt 50 of a variator V to a position of lowest gear ratio. As a result, the longitudinal-slide shift control is not executed in a state in which an excessive torque acts, so that durability of the belt and a pulley improves.

Exercise device for suspended body weight training

Abstract: A pulley system of an exercise device for suspended weight training includes a first block with a first pulley, a second pulley, and a first attachment point. A second block is removably coupled to a weight and includes a third pulley and a second attachment point. A grip is configured to be held by a user while exercising and has a third attachment point. A line having a first line end is fixedly coupled to the grip and a second line end fixedly is coupled to a connection element. The connection element is configured to be selectively coupled to each of the first attachment point, the second attachment point, and the third attachment point, permits a user to reduce an effective amount of the weight lifted by the user with movement of the grip to a pre-selected fraction of the weight.

Automatic waste collecting device for stamping die

Abstract: The invention provides an automatic waste collecting device for a stamping die. The automatic waste collecting device comprises a conveyer, a waste recovery box, a power device and an auxiliary structure positioned on the stamping die, wherein the conveyer comprises a fixed pulley support, a support, a belt and a belt shaft which are fixed on a stamping workbench; the support is connected with the belt shaft through a bearing; the fixed pulley support is provided with a fixed pulley capable of rotating around the fixed pulley support; the fixed pulley is connected with the belt shaft through the belt; the right side of the damping die is provided with an inclined chute; the other end of the inclined chute is connected with the waste recovery box; the power device comprises a motor; a supporting table is arranged below the motor; the output shaft of the motor is connected with the belt shaft through a coupling. The automatic waste collecting device is simple in structure, stamping waste can be automatically collected, halt is not required for cleaning the waste, the working efficiency is improved, the working environment is improved, and the damage of the die caused by the blockage of the waste is avoided.

Cable laying device

Abstract: The invention discloses a cable laying device. The cable laying device comprises a base, cable trays, a cable, a fixing frame, a guide support and a third pulley; three groups of universal wheels are distributed on each side below the base; two supporting columns are symmetrically arranged above the bilateral sides of the left end of the base respectively; supporting frames are fixedly arranged on the bilateral sides of the outer wall of each supporting column respectively; a hydraulic jack is fixedly arranged at the upper end of each supporting column; a supporting groove which is in a circular arc shape is fixedly formed above each hydraulic jack; a rotating shaft is arranged between the two supporting grooves in a straddled mode; the cable trays are arranged in the supporting grooves through the rotating shaft respectively; the upper end of the guide support is provided with a beam; an elastic guide device is fixed in the middle of the bottom surface of the beam; an elastic guide base, a first guide wheel and a spring are arranged in the elastic guide device. According to the cable laying device, the operation is simple, the use is convenient, the height of each cable supporting frame can be adjusted, the friction force in the movement process of the cable is reduced due to a pulley group, and accordingly the labor intensity of the construction personnel is reduced.

Pull test system and method of pipe-laying ship

Abstract: The invention discloses a pull test system of a pipe-laying ship. The pull test system of the pipe-laying ship comprises a guide pulley, a tooling steel cable, a triangular plate, a traction winch cable, a universal tube connector, a tensioner, a traction winch and a pipe, wherein the triangular plate is connected to the traction winch through the traction winch cable, the universal tube connector is connected to the pipe penetreating the tensioner, the traction winch cable penetrates the universal tube connector, the guide pulley is fixedly connected to a fixed base, the tooling cable is wound through the guide pulley to be connected to the triangular plate and the universal tube connector respectively, and the universal tube connector comprises a hauling eye plate. The invention further discloses a pull test method of the pipe-laying ship. The pull test system of the pipe-laying ship uses a detachable deflecting pulley device to replace a traditional fixed lifting lug and is provided with a universal traction connector applicable to tubes of different diameters through refit, thereby greatly reducing the occupation space of the pull test system, improving the efficiency and solving the problem of the conflict of the guide pulley located in the middle side of the ship with other equipment.

Unloading of electron tobacco pipe and laser flight marking arrangement

Abstract: The utility model relates to an electron cigarette technical field discloses an unloading of electron tobacco pipe and laser flight marking arrangement, including automatic unloading mechanism, laser marking machine, receive magazine, transfer chain and frame, wherein, automatic unloading mechanism includes magazine, rotary wheel, connecting block and motor, goes up magazine, rotary wheel and connecting block and from top to bottom sets gradually, the motor is connected with the rotary wheel, upward the magazine discharge gate and the stock chest on the connecting block respectively with the rotary wheel wheel face on groove position corresponding, be provided with the transfer chain on the frame, the transfer chain adopts band pulley and belt realization transmission, on the frame also was provided in automatic unloading mechanism, the stock chest on the connecting block was also corresponding with the belt position of transfer chain, the laser marking machine is provided the frame on to be located the top of transfer chain belt The utility model discloses can improve production efficiency greatly and reduce the cost of labor, the operation is also more simple and convenient

Mechanical mechanism of robot

Abstract: The utility model provides a mechanical mechanism of robot, include a base junction part, two big arm junction parts, triaxial junction part, forearm junction, five synchronous pulley junctions, six axle bed junction parts and terminal hand claw spare constitution all around. The structure of line is conveniently walked and can guarantee can not cause the intertwine of cable at the in -process of each rotation of axes to special local design, wrist department part all adopts the design of aluminium alloy material, can effectively alleviate the dead weight of wrist department, again can the proof strength, on the four -axis motor was fixed in three four -axis seats, the outside was equipped with four -axis motor guard shield, and during five motors were fixed in the inboard cavity of forearm, the outside was sealed through five shaft -cup boards, and inside six motors were fixed in six axle beds, the outside was equipped with apron no. 1 and end cover no. 3, makeed whole compact structure like this, and is pleasing to the eye, an unified entity. The utility model discloses the structure is simple relatively, and control is convenient, has satisfied the automated control demand.