53 results about "Sprocket" patented technology

The present invention relates to a zero turning radius vehicle having at least one steerable front wheel and a multistage steering input system separately capable of steering the at least one front wheel and selectively driving the drive wheels. A front wheel steering system comprises at least one oblongated sprocket meshingly connected to a steering shaft. An engagement cam system provides the ability to selectively, independently couple the steering wheel to pump arms driving a first and second drive wheel. A steering cam shaft comprises at least one steering cam that acts on at least one bearing. Once the engagement cam system rotates the at least one bearing into place to receive the at least one steering cam, rotation of the steering cam independently alters the speed of one drive wheel in relation to the other drive wheel in response to steering input provided by the operator.

The Ring Rack Oil Pumping Machine is comprised of: a base, a frame mounted on the base, a roller mounted at the frame top, a sprocket case connects to the middle of the frame; a input shaft having a lower sprocket and a drive shaft having an upper sprocket are installed at the bottom and top of the sprocket case respectively, the upper sprocket and lower sprocket are connected by a chain; a guide wheel, track gear and centralizer wheel are mounted in sequence on the end of the drive shaft extended out of the sprocket case; the track gear meshes with a rack, a slide rail is mounted with the frame, and a sliding base (21) connected with the slide rail (20) moveably. Comparing to currently using pumping units, this invention features simple structure, high safety and reliability, upgraded efficiency, easy maintenance, smooth running and high durability.

The invention discloses an automatic spring leading device of independent bagging spring machine that includes main chain wheel, driven chain wheel, chain rolling on main chain wheel and driven chain wheel, block transferring board that has flute on it, and magnet inlayed in the flute. The invention has simple structure and is suitable to use in bagging machine.

The balancing weight unit of ring spindle spinning frame includes a dragging mechanism comprising fixed chain wheel, forming cam, oscillating arm, main dragging chain and main chain wheel; an elevating mechanism comprising driven chain wheel, elevating chain, elevating part and transition chain wheel; and a balancing weight mechanism comprising two transmissino chain wheels, suspending chain, balancing weight and upper distribution shaft. The two transmission chain wheels are connected through the suspending chain to the balancing weight; and the main chain wheel, the two transmission chain wheels and the driven chain wheel are set successively on the upper distribution shaft for elevation motion.

The invention provides a multifunctional drawing machine which comprises a balance weight wheel, a transmission box body, four drawing wheels, axles, a driving chain wheel, a transmission chain, a driven chain wheel, a protection plate, a lifting operation wheel, a lifting frame, a machine seat, transmission shafts, a rotating shaft, an angle adjustment handwheel, an angle adjustment driving shaft, a transverse adjustment wheel, a transverse adjustment shaft, rollers and a conveying belt, wherein the four drawing wheels are mounted at the upper part of the conveying belt through the axles; the driving chain wheel is connected with the driven chain wheel through the transmission chain; and the driven chain wheel is connected with the rollers. By the arrangement of the lifting operation wheel, the lifting frame, the rotating shaft, the angle adjustment handwheel, the angle adjustment driving shaft, the transverse adjustment wheel and the transverse adjustment shaft, the multifunctional drawing machine realizes horizontal left-and-right movement and up-and-down lifting adjustment of the drawing wires; by the adjustment of an angle of the conveying belt, stereoscopic drawing is realized; multifunctionality is realized; the equipment utilization rate is increased; and the multifunctional drawing machine is convenient to popularize and use.

The invention discloses a mechanical type loosening and breaking preventing safety device for a chain. The mechanical type loosening and breaking preventing safety device comprises a stand column, a fixed rack, a chain wheel mechanism, a lifting platform and a loosening and breaking preventing device, wherein both the fixed rack and the chain wheel mechanism are fixedly arranged on the stand column; the gear surface of the fixed rack is equipped with the loosening and breaking preventing device in parallel, and is spaced with the loosening and breaking preventing device by certain horizontal distance; and the loosening and breaking preventing device is fixedly connected to the lifting platform, and realizes up-down motion of the lifting platform through the chain wheel mechanism. The mechanical type loosening and breaking preventing safety device for the chain disclosed by the invention adopts a mechanical type structure, is not affected by an external environment, ensures that a stacker and a RGV lifting platform to not drop in cases such as chain breakage stalling loss, greatly improves safety performance of the lifting platform, avoids occurrence of a safety accident, is simplein structure, is safe and reliable, and is liable to implement.

The invention discloses a screening and crushing bucket, which belongs to an engineering machinery accessory. The screening and crushing bucket comprises a bucket body, a hydraulic motor, a screening and crushing mechanism, a transmission case and a transmission mechanism, wherein the bucket body comprises two side walls which are oppositely arranged, T-shaped grooves which are convenient for installing the screening and crushing mechanism are formed in the lower sides of the two side walls, the transmission case is arranged outside one side wall and covers the T-shaped groove and a driving wheel mounting hole, the screening and crushing mechanism comprises three rolling shafts installed in the T-shaped grooves and knife boards installed on the rolling shafts, no gap exists between the adjacent knife boards, three driven chain wheels are fixedly connected to the same end of the three rolling shafts respectively, the hydraulic motor is directly connected with a driving chain wheel, the driven chain wheel I is driven by the driving chain wheel through a chain, the driven chain wheel II is driven by the driven chain wheel I through a chain, and the driven chain wheel III is driven by the driven chain wheel II through a chain. The screening and crushing bucket can be used for screening and crushing on any occasion and has the advantage of low cost.

The invention discloses a three-ridge six-row peanut seedling and fruit integrated combined harvesting machine which is composed of a walking system, a fruit pulling system and a fruit picking system,wherein the walking system comprises a machine frame, driving wheels are arranged on the two sides of the front end of the machine frame, and walking wheels are arranged on the two sides of the rearend of the machine frame; the fruit pulling system is arranged at the front end of the machine frame and comprises a support, three groups of six seedling righting rods are arranged at the front end of the support and are used for righting the peanut seedlings, three groups of clamping chain wheels are arranged under the seedling righting rods side by side, three groups of six shovel blades are arranged under the clamping chain wheels, and a seedling clipper is arranged at the rear end of the support; the fruit picking system is composed of a seedling lifting device, a root lifting device, a grass collecting box and a fruit picker, and the seedling lifting device, the root lifting device, the grass collecting box and the fruit picker are all arranged on the machine frame. The three-ridge six-row peanut seedling and fruit integrated combined harvesting machine has the beneficial effects that once three-ridge six-row peanut seedling and fruit combined harvesting is utilized to achieve afull process of peanut digging, seedling and root shearing and separation and fruit picking; a feeding quantity is large, fruit picking performance is good, a peanut breaking rate is low, peanut seedlings and nuts are integrally harvested, and a work efficiency is high; the harvesting machine is especially suitable for large parcel or farm operation.

The invention proposes a chain transmission mechanism for a grinding machine. The mechanism comprises a bracket, a first shell, a second shell, a motor, a speed reducer, a driving chain wheel, a guide shaft, a driven chain wheel, a chain and a tension adjusting mechanism; the tension adjusting mechanism includes an adjusting block fixed shaft, an adjusting block, an adjusting chain wheel shaft, an adjusting chain wheel, an adjusting spring fixed piece, an adjusting spring, an adjusting screw rod and an adjusting screw rod fixed base; the adjusting chain wheel is positioned on the inner side of the chain; the adjusting screw rod rotates in the adjusting screw rod fixed base; and the adjusting spring drives the adjusting chain wheel to move to one side of a center connecting line of the driving chain wheel and the driven chain wheel, so that the chain is tensioned, the transmission efficiency and the transmission stability are improved, and the polishing precision and the polishing efficiency of the grinding machine are improved.

The invention discloses a steel bar scattering machine and a steel bar feeding machine, and relates to the technical field of machine manufacturing. The steel bar scattering machine comprises a rack, a plurality of sets of chain wheel and chain transmission assemblies are erected on the rack, and a chain wheel transmission shaft is arranged on the rack and connected with a rotary driving mechanism; driving chain wheels of the multiple chain wheel and chain assemblies are arranged on the chain wheel transmission shaft in a sleeving manner and coaxially and fixedly connected with the chain wheel transmission shaft; and a material stirring transmission shaft is erected on the rack in a rotating manner, the material stirring transmission shaft is connected with a material stirring driving mechanism, and a plurality of material stirring cam plates are coaxially fixed to the material stirring transmission shaft at intervals. The steel bar feeding machine comprises the steel bar scattering machine and a steel bar twisting machine; and manual material selecting and discharging operation is achieved, the manual operation intensity is reduced, the production efficiency is improved, the functions of automatic straightening, material distributing, material discharging and feeding of reinforcing steel bars are achieved, the application range is wide, mechanism transmission is stable, cost is low, and practicability is high.

The invention relates to a tensioning and locking device for a chain of a chain saw, which comprises the chain, a chain tensioning device mutually assembled with the chain, and a locking device for locking the chain tensioning device, wherein the chain tensioning device comprises a guide plate arranged together with the chain, a chain sprocket enabling one end of the chain to be clamped on the chain sprocket, a tensioning block arranged together with the guide plate, and a drive device for driving the tensioning block to move towards a normal direction of a plane of the guide plate and a direction deviate from the chain sprocket. In a tensioning process of the chain, the tensioning block is at a movement state, and the tensioning block is moved in the direction deviate from the chain sprocket so as to drive the guide plate to move along the same direction, so that the aim of tensioning the chain is achieved, and the operation is simple and convenient.

The invention discloses an endoscope transmission mechanism and an endoscope with the transmission mechanism. The transmission mechanism comprises a driving device, a shell, an active gear, an upper shell traction rack, a push rod, a lower shell traction rack, driven gears, chain wheels, chains and steel wires; two pairs of racks drive two pairs of driven gears at the lower shell of the endoscope, a chain wheel is attached on the driven gears, chains are arranged on the chain wheel, two ends of the chain are connected with the steel wires respectively, when the racks are driven by the push rod, the racks drive the gears to rotate, the rotation of the gears drives chains to make coaxial synchronous rotation, the connection of the steel wires and chains is fixed using steel wire clamping buckles, welding is not needed, the heavy acid mist vapor pollution and the personal injury to an operator caused by rinsing with concentrated acid when welding the steel wires is avoided, and the adjustment and maintenance at a later stage are also facilitated.

The invention relates to a lateral displacement device for a vehicle, which comprises a mechanical device and a control device. The mechanical device comprises four case bodies fixedly mounted at the bottom of a vehicle frame, wherein in each case body, a supporting arm that is slightly smaller than the case body can be mounted inside the case body, the rear end of the supporting arm is movably connected with a first rotating shaft, the first rotating shaft is movably mounted on the case body, the rear part of a hydraulic cylinder is connected with a second rotating shaft, the second rotating shaft is movably arranged on the case body, a rolling wheel is fixedly connected with a third rotating shaft, the third rotating shaft is mounted at the front end of the supporting arm, a first chain wheel is fixed on the part of the third rotating shaft, which is exposed outside the case body, the front end of the driving shaft of the hydraulic cylinder is movably connected with a fourth rotating shaft, and the fourth rotating shaft is movably arranged on the supporting arm; a reducer fixing case body, a reducer and a motor are mounted in sequence on the outer side of the rear part of the case body; the output shaft of the reducer faces to the case body; a second chain wheel is fixedly arranged on the output shaft of the reducer; and the first chain wheel and the second chain wheel are movably connected through a chain. The lateral displacement device for the vehicle can allow the vehicle to perform a lateral motion with a small displacement, and has the characteristics of simple structure, convenience in installation and easiness in operation.

The invention provides an angular rotating locating mechanism. The angular rotating locating mechanism comprises a rotating platform, a base plate, a hydraulic buffer seat, a slider and a rack mounting block, wherein a spur rack is mounted on the rack mounting block, the rack mounting block is fixed to the slider, the slider and a linear guiding rail form a sliding pair, the linear guiding rail is fixed to a guiding rail fixer, the guiding rail fixer is fixed to the base plate, a cylinder mounting base is fixed to the base plate, a cylinder is fixed to the cylinder mounting base, a cam following device is mounted on the base plate through a following device bracket, a tapered roller bearing is mounted on a bearing pedestal, a spur gear is limited to a rotating shaft through shaft bushings at the two sides, and a rotating flat plate is fixed to the rotating shaft. The angular rotating locating mechanism has the following beneficial effects that the problems that original sprocket-chain transmission motion process is unstable, chain clearances cause inaccurate rotating angle, and a motor driving sprocket-chain structure is complicated in technology, high in cost and has high requirement on equipment mounting precision are effectively solved.

The invention discloses a power transmission of a rootstock excavator, which is characterized in that a reduction box is connected between the front ends of two boundary beams; a circular chain box transmission shaft is mounted between the rear ends of the two boundary beams by bolts and bearing supports; a pair of bridge sector gears is mounted in the reduction box; a power input shaft extending from the front of the reduction box is mounted on the bridge sector gear in the front of the reduction box; output shafts at the two ends of the bridge sector gear at the back are connected with semi-floating half shafts respectively; the outer ends of the two semi-floating half shafts extend out of the boundary beams from the interior of the reduction box through bearing supports; a chain wheel is mounted at the outer end of each semi-floating half shaft; a rear chain wheel is mounted at each of the two ends of the circular chain box transmission shaft; power output crankshaft connecting rods are respectively mounted on the chain wheels; and a chain is connected between the front chain wheel and the rear chain wheel on one side. The power transmission has the advantages of simple structure, light weight, small size, low energy consumption, high efficiency, low noise and stable and reliable operation.

The invention relates to a no-missing chain-driven rotary cultivator with functions of soil casting, stubble cleaning and subsoiling, which comprises a chain drive box assembly disposed in an intermediate drive manner. A power input shaft and a transmission sprocket shaft are disposed inside the front end of a chain drive box, and a power input sprocket is further disposed on the transmission sprocket shaft. A power output shaft is disposed inside the rear end of the chain drive box, and a power output sprocket is disposed on the power output shaft. A transmission chain is disposed on the power input sprocket and the power output sprocket. Two ends of the power output shaft respectively extend out of the chain drive box to be connected to a coupling with a flange, the coupling is connected with a subsoiling cutter shaft assembly, and a turning tool and a coulter are disposed on the coupling. The subsoiling cutter shaft assembly is connected with a support shaft through the flange, the support shaft is connected to a support arm, and the support arm is connected with the chain drive box through a support casing. The no-missing chain-driven rotary cultivator with functions of soil casting, stubble cleaning and subsoiling is simple in manufacture, easy in production, low in cost, high in universality, convenient in maintenance and energy-saving, and has rotary cultivation, stubble cleaning and subsoiling efficiency approximately doubled.

The invention discloses a cable take-up and pay-off device for communication engineering. The cable take-up and pay-off device comprises a bottom plate, wherein the top of the bottom plate is rotationally connected with two rotating rollers with the adjustable spacing, and two chain wheels are arranged on one sides of the rotating rollers and rotationally connected to the bottom plate; the two chain wheels are connected through a transmission chain, and a hollow sleeve is rotationally connected to the transmission chain; and a driving device is arranged on one side of the transmission chain. The cable take-up and pay-off device is simple in structure. A cable sequentially penetrates through the hollow sleeve, a second rotating wheel and a rotating sleeve. The cable moves, the second rotating wheel is driven to rotate, and then a first transmission belt drives the transmission chain to rotate. The transmission chain drives the hollow sleeve on the transmission chain to reciprocate, andthen the cable is pulled to be wound on a coil in a reciprocating mode and prevented from being wound. Meanwhile, a second transmission belt drives a worm to rotate, the worm is meshed with a worm wheel to drive the rotating sleeve to rotate, and the rotating sleeve drives a spiral brush in the rotating sleeve to clean the surface of the cable, so that cleanliness of the cable is guaranteed.

The invention discloses a wind-driven water pumping device comprising a vertical rod, a connection plate and a wind blade assembly. The wind-driven water pumping device further comprises two chain wheels, two connection rods, a piston water pump, a water inlet pipe and a water outlet pipe. The connection plate is rotationally connected with the upper end of the vertical rod; the wind blade assembly is formed by a rotating shaft; the rotating shaft is rotationally connected with the connection plate; the chain wheel is rotationally connected with the connection plate; the chain wheel is connected with the rotating shaft via a transmission chain; the upper end of the connection rod is rotationally connected with the edge of the chain wheel; and the piston water pump has a plunger. The wind-driven water pumping device is advantaged by relative low installation precision and low production cost due to transmission by the chain wheel; with the piston water pump, water can be pumped even when the wind power is weak, so great reliability can be achieved; and with a water storage bucket, a water rush hour can be alleviated.

The invention relates to the technical field of scooters, and discloses an electric frog kick scooter, which comprises a scooter head elbow (1), a front fork member (2) connected with the scooter head elbow (1), and a slide board (3) connected with the scooter head elbow (1), wherein a front wheel (4) and an axletree (5) running though the front wheel (4) are arranged on the front fork member (2), and the axletree (5) is connected with the front fork member (2); a flywheel (6) connected with the front wheel (4) and a motor (7) connected with the flywheel (6) are arranged on the front fork member (2), and a chain wheel (12) connected with the flywheel (6) is arranged on the flywheel (6); the motor (7) is connected with the chain wheel (12) by a chain (13). The motor drives the front wheel to rotate and thereby driving the scooter to move forward without thrust by foot, so the scooter is labor-saving and more convenient to use; the motor and the front wheel are driven by the flywheel and the chain wheel to transmit, and left and right back wheels are swung by thrusting the slide board by foot to drive the scooter to move forward after the motor is turned off, so the function of the scooter is enriched.

The present invention discloses an engine timing chamber structure. A cylinder head (3), an upper cam shaft frame (1) and a lower cam shaft frame (2) form the timing chamber; a timing chamber head (8) is added outside the timing chamber; the timing chamber head (8), the cylinder head (3), the upper cam shaft frame (1) and the lower cam shaft frame (2) are connected through a plurality of fastening bolts (9, 10, to,21) and a seal glue, thus forming an enclosed hollow cavity. The method of painting the flat anaerobic seal glue is adopted to seal the cylinder head (3) and the lower cam shaft frame (2) as well as the upper cam shaft frame (1) and the lower cam shaft frame (2); the timing chamber adopts silicon rubber sealing. The timing chamber structure provided by the present invention ensures not only the convenient installation and maintenance of the timing chain and the chain wheel but also no lubricant leakage required by the normal operation of the timing system; at the same time, the dust outside is unable to enter the timing chamber and affect the operation of the timing system. The present invention not only solves the installation and maintenance of the timing system but also simplifies the structure of the cylinder head and the cam shaft frame.

The invention discloses a guide pipe softening bending device. The guide pipe softening bending device comprises a device body, a through groove with a forward opening is formed in the front side wallof the device body, the left side of the through groove penetrates through the device body, a bending groove communicating with the through groove is formed in the position, on the right side of thethrough groove, of the device body, a working cavity is formed in the rear side of the bending groove, the upper side wall and the right side wall of the bending groove with a forward opening both penetrate through the device body, and a clamping groove communicating with the upper side wall and the lower side wall of the through groove is formed in the rear side of the through groove. A connecting chain is collected through a chain wheel to drive a movable rod to move so as to achieve overturning of a secondary clamping groove, a guide pipe is fixed through connecting ropes and clamping blocks in the overturning process of the secondary clamping groove to guarantee normal work, meanwhile, a roller is driven to rotate, a heating block is made to reciprocate up and down to perform heating-assisted bending work on the guide pipe, meanwhile, it is guaranteed that wrinkles are reduced, and the guide pipe is protected.

The invention relates to a double speed chain transmission device, which comprises two layers of aluminum alloy frames. The upper parts and middle parts of the two layers of aluminum alloy frames areprovided with conveying guide rail inner frames; the left sides and right sides of the conveying guide rail inner frames are provided with chain wheels; chains for connecting the chain wheels on the left sides with the chain wheels on the right sides in a transmission manner are arranged between the chain wheels on the left sides with the chain wheels on the right sides; motors are arranged belowthe chain wheels located on the left sides; and differential transmission mechanisms for connecting the chain wheels located on the left sides and the corresponding motors are arranged between the chain wheels located on the left sides and the corresponding motors. The double speed chain transmission device disclosed by the invention is relatively high in automation degree, can efficiently, automatically and horizontally transport a large number of fiber spools under the driving of the two chains and also guarantee the stability of transportation; and in addition, the fiber spools can be automatically lifted up in the transportation progress to achieve an effect of facilitating machining and treatment.

The invention discloses a hydraulic lifting wall brushing machine manually controlled by sprockets and chains. The hydraulic lifting wall brushing machine comprises a first base, a second base, a paste spraying cylinder and a rolling brush. The paste spraying cylinder is connected with a coating material tank. Stand columns are fixed on the second base. The lower portion of one stand column is provided with a second driving sprocket and a first driven sprocket, wherein the second driving sprocket and the first driven sprocket are arranged coaxially. The upper portion of one stand column is provided with a second driven sprocket. The second driving sprocket is connected with the second driven sprocket through the second chain. One sliding block is fixed on the second chain. The sliding blocks are fixedly connected with the paste spraying cylinder. Connecting rods are fixed on the two ends of the paste spraying cylinder. A rolling brush shaft is fixed between the two connecting rods. The rolling brush shaft is provided with the rolling brush. The first base is arranged below the second base. A hydraulic cylinder is arranged between the first base and the second base. A first driving sprocket is arranged on the first base. The first driving sprocket is connected with the first driven sprocket through a first chain. According to the hydraulic lifting wall brushing machine, the height of the rolling brush is convenient to adjust, the wall brushing speed is increased, coating materials are saved, and the decoration cost is lowered.

A synchronous conveying mechanism for a neural cable comprises a large driving wheel, a small diving wheel arranged opposite to the large driving wheel, and the neural cable penetrating the space between the large driving wheel and the small driving wheel; the small driving wheel is supported by a small driving wheel supporting rocker which is supported by an intermediate shaft; the two sides of the large driving wheel and the small driving wheel are each provided with a hydraulic slave oil cylinder; a large driving wheel shaft and a large driving wheel shaft chain wheel are driven by a hydraulic motor to rotate; through transmission of a first transmission chain and a plurality of idle wheels, the intermediate shaft, a first intermediate shaft chain wheel and a second intermediate shaft chain wheel are driven to rotate in opposite directions; a second transmission chain drives a small driving wheel shaft and a small driving wheel shaft chain wheel to rotate in the same direction; and then due to the fact that the large driving wheel and the small driving wheel make reverse opposite rotation movement, the neutral cable is conveyed to enter and leave a single-person normal pressure diving apparatus meshing device. Pre-tightening force is provided for the synchronous conveying mechanism for the neutral cable through the hydraulic slave oil cylinder, and the neutral cable winding and unwinding stability and reliability of the synchronous conveying mechanism are greatly improved.

The invention discloses equipment capable of cleaning a transformer and protecting detection. The equipment comprises an equipment box body, a storage cavity is fixedly connected to the end wall of the upper side of the equipment box body, an auxiliary device is arranged in the storage cavity, and the auxiliary device is used for collecting a water source. According to the equipment capable of cleaning a transformer and protecting detection, cleaning of the transformer can be realized. Daily rainwater is collected and filtered through the auxiliary device. When the collected water amount reaches a certain amount, a cleaning device can be triggered, a cleaning rod is driven to move through chain wheel transmission, dust removal and cleaning are conducted on the cooling fins in cooperation with a collected water source, and potential safety hazards of dust to the transformer are reduced. Meanwhile, when the cable on the upper side of the transformer is broken, falls off and is on fire, the safety device can be used for starting the pre-warning lamp to illuminate to prevent people from entering, the valve is opened to start fire extinguishing measures to reduce the danger of people, and the detection device can be used for performing air leakage detection inside the transformer oil tank to prevent accident potentials.

The invention discloses a dibbling-raised seedling sowing machine and belongs to agricultural machinery. The sowing machine provided by the invention has the aims of being capable of being matched with a seedling raising bushing chain and being capable of serving as an ordinary sower. The sowing machine comprises a sowing mechanism and a vibrating mechanism, wherein the sowing mechanism consists of a main shaft (13), a sowing tray (5), a first chain wheel (16), a plurality of sowing holes (22), a plurality of snapping grooves (26), a plurality of valve plates (25), torsion springs (23), a guiding hopper (7) and a stopper pin (24), wherein the main shaft (13) is supported on a machine frame (8), the sowing tray (5) and the first chain wheel (16) are fixed to the main shaft, the sowing holes (22) are uniformly distributed in the sowing tray (5), the snapping grooves (26) are distributed along the edge of the sowing tray (5), the valve plates (25) are separately hinged to the back of the sowing tray (5), the torsion springs (23) are separately fixed to all pin shafts (27) and compress the valve plates, the guiding hopper (7) is in butted joint with one sowing hole (22), and the stopper pin (24) is located nearby the guiding hopper. The sowing machine has the advantages of simple structure, convenience in operation, small size, light weight, high efficiency, accurate sowing distance and the like and belongs to seeding machinery.