CN206149820U - Mechanism is planted to two -degree -of -freedom train rice pot width course - Google Patents

Abstract

The utility model discloses a mechanism is planted to two -degree -of -freedom train rice pot width course. The mechanism is transplanted to present single degree of freedom's planetary gear train alms bowl width of seedling shoot narrow row, and to have when getting the seedling transverse offset too big, leads to the fact the seedling accurate problem inadequately of getting. The utility model discloses the form that adopts gear drive and chain drive to combine together in the transmission case of well two -degree -of -freedom train, the interior gear combination that adopts non -circular gear and crisscross helical gear of gear box, because two power inputs of two -degree -of -freedom train, the variable speed transmission characteristic of combination non -circular gear makes the mechanism can realize the drive ratio of free alternation to realize complicated transplantation orbit, the orbit is a straight line when getting the seedling, does not have transverse offset, can realize the accurate seedling of getting, guarantees the success rate of getting the seedling. The utility model discloses a space skew mainly realizes by the helical gear of crisscross installation, and is simpler than the space bevel gear of present mechanism, moves in the assurance simultaneously and has realized " directly getting the seedling " under the circumstances that the width course planted.

Description

A kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism

Technical field

The utility model belongs to agricultural mechanical field, is related to high-speed rice pot seedling width line transplanter, and in particular to a kind of Two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism.

Background technology

At present, rice transplanter is numerous in variety, but the either wide-and narrow-row rice transplanting line-spacing rice transplanting such as still, and transplanting mechanism is taken Rice shoot all be blanket seedling, easily hinder root.And the rice shoot that pot seedling wide-and narrow-row transplanting mechanism is taken be pot seedling, the seedling between alms bowl and alms bowl There is no packing phenomenon, so not there are problems that hindering root in seedling taking process, compare blanket seedling rice transplanting and there is shorter turning green week Phase, this is significant to improving rice yield.

Wide-and narrow-row rice plantation refers to that rice seedling plant line space carries out one wide one narrow planting patterns, this plantation side Formula, by the line space for adjusting rice shoot, improves ventilation, light transmittance between plant using the principles of increase yield of crop Edge advantages, mitigates Pest and disease damage, so as to reach the purpose of paddy rice good quality and high output.

Wide-and narrow-row transplanting mechanism is to realize rice shoot wide-and narrow-row on the basis of existing pot seedling transplanter seedling box structure is not changed The part of line-spacing plantation is not waited.The patent application of Publication No. TN102640604M discloses a kind of high-speed transplanter non-circular gear Wide-and narrow-row transplanting mechanism, although first order helical gear and second level non-circular gear drive are refer in the patent application, realizes wide Narrow row rice transplanting, its characteristics of motion meets to a certain extent the seedling taking of transplanting mechanism seedling pin, rice transplanting track and attitude, but its work( " kidney-shaped " track or " dolphin shape " track of rice transplanter can be only limitted to, " 8-shaped " required for potted-seedling transplanting can not be formed Spatial complex track, i.e., the mechanism that the patent is proposed is applicable only to rice transplanter, can not meet the shifting of accurate rice pot seedling wide-and narrow-row The requirement of cultivation.

The patent of Publication No. CN103004346A discloses a kind of not rounded bevel gear pot seedling wide-and narrow-row transplanting mechanism, and this is special The seedling taking action of the combining form mechanism of the spur gear, helical gear and non-circular gear that propose in profit is " folder soil ", i.e., in seedling taking What intermediate plate was clamped is the bowl-entering soil of pot seedling in journey；The track of transplanting of the mechanism is the space motion path with sharp mouth, is made in high speed Larger impact shock is had during industry, reliability is not high.

The patent application of Application No. CN201310318352.7 discloses a kind of seven non-conical bevel gear planet circular system alms bowl Width of seedling shoot narrow row transplanting mechanism, the core component of the mechanism is the planet circular system of seven non-conical bevel gears, and its seedling claw can be realized The space motion path of " 8-shaped ", but " 8-shaped " of the mechanism transplants track and has larger transversal displacement in seedling taking section, That is seedling taking pawl action of lateral shift again while seedling taking, interferes with the left and right seedling sending action of seedling case, causes seedling taking not Accurately, seedling taking success rate is relatively low.

The content of the invention

The purpose of this utility model is to be directed to the deficiencies in the prior art, there is provided one kind is applied to high-speed rice pot seedling transplanter Two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism.

In order to achieve the above object, the technical solution adopted in the utility model is：

The utility model includes transmission case, final drive shaft, drive bevel gear, driven wheel of differential, counter drive shaft, drive chain Wheel, central shaft, chain, center sprocket wheel, two degrees of freedom train, upper transplanting arm and lower transplanting arm；Described final drive shaft, auxiliary driving Axle and central shaft are bearing on transmission case by bearing, and drive bevel gear is fixed on final drive shaft, driven wheel of differential and master Movable sprocket is each attached on counter drive shaft；Described driven wheel of differential is engaged with drive bevel gear；Center sprocket wheel is fixed on center On axle, and it is connected by chain with drive sprocket；Two two degrees of freedom trains are symmetricly set on the two ends of central shaft.

Described two degrees of freedom train include differential driving gear, differential driven gear, gear-box, center non-circular gear, Upper middle non-circular gear, upper middle helical gear, upper planet helical gear, lower middle non-circular gear, lower middle helical gear and lower planet Helical gear, and the upper jackshaft in gear-box, upper planet axle, lower jackshaft and lower planet axle are bearing in by bearing；It is described Differential driving gear be fixed on counter drive shaft；Differential driven gear empty set on center shaft, and is nibbled with differential driving gear Close；The end that gear-box stretches out outside transmission case with central shaft is fixed by pin；Described center non-circular gear by dental inlay with Differential driven gear is fixed；Upper middle non-circular gear and upper middle helical gear are each attached on jackshaft；The non-knuckle-tooth in upper centre The non-circular gear engagement of Lun Yu centers；Upper planet helical gear is fixed on upper planet axle, and is engaged with upper middle helical gear；Lower centre Non-circular gear and lower middle helical gear are each attached on lower jackshaft；Lower middle non-circular gear is engaged with center non-circular gear；Under Epicyclic singleplent helical gear is fixed on lower planet axle, and is engaged with lower middle helical gear.

One end that the transplant arm housing of the upper transplanting arm goes out outside gear-box with upper planet shaft extension is fixed, the shifting of lower transplanting arm One end that cultivation arm housing goes out outside gear-box with lower planet shaft extension is fixed, and upper transplanting arm and lower transplanting arm are arranged on the same of gear-box Side；The cam of upper transplanting arm and lower transplanting arm is fixed with gear-box；Upper transplanting arm is identical with the structure of lower transplanting arm.

Described upper jackshaft and lower jackshaft is symmetricly set on central shaft both sides；Described upper planet axle and lower planet axle Central shaft both sides are symmetricly set on, the crossed axis angle between upper planet axle and central shaft, lower planet axle and central shaft is Φ；In upper Between helical gear, upper planet helical gear, lower middle helical gear and the helical gear helical angle of lower planet be β；Φ=2 β；β is according to width The line-spacing that narrow row is transplanted requires value.

The pitch curve of the center non-circular gear is formed by cubic nonratio- nal B-spline curve fitting.

The geometric parameter of the upper middle non-circular gear and lower middle non-circular gear is identical, and upper middle helical gear is with Middle helical gear geometric parameter is identical, and upper planet helical gear is identical with the helical gear geometric parameter of lower planet；Institute State that the helical gear number of teeth of upper planet is the upper middle helical gear number of teeth 2 times, the helical gear number of teeth of lower planet is lower middle helical gear 2 times of the number of teeth.

The gearratio of the drive sprocket and center sprocket wheel is 1.

Described differential driving gear and differential driven gear is Knucle-gear, and gearratio is 1, or for intermeshing Non-circular gear.

The seedling taking section of the transplanting track that the seedling taking intermediate plate cusp of upper transplanting arm or lower transplanting arm is formed is in the horizontal plane It is projected as straight line section.

The beneficial effects of the utility model are：

1st, the utility model solves staggered gear-elliptic cone planetary gear train and staggered gear-non-circular gear is transplanted Mechanism is applicable only to the problem of rice transplanter, and compared to " kidney-shaped " and " dolphin shape " of these transplanting mechanisms track is transplanted, this The transplanting mechanism of utility model can form space " 8-shaped " track of complexity, to adapt to the particular/special requirement of accurate rice pot seedling transplanting. Potted-seedling transplanting is the agronomic technique more advanced than transplanting, also more difficult on specific enforcement, thus the utility model with Simple gear mechanism realizes the irrealizable pot seedling wide-and narrow-row of transplanting mechanism institute of rice transplanter and transplants function, can be paddy rice High-quality is increased production and further mechanization contributes.

2nd, the utility model is binary two degrees of freedom train transplanting mechanism, with traditional single-degree-of-freedom planet circular system Transplanting mechanism is different, and two degrees of freedom train transplanting mechanism can realize the gearratio of complexity, meanwhile, plane non-circular gear with staggeredly The form of helical gear combination so that the planet circular system of transplanting mechanism possesses space transmission while with variable speed drive characteristic Characteristic, enables transplanting mechanism to realize the transplanting track of complexity；Simultaneously as the gearratio of mechanical flexibility so that mechanism only needs The helical gear being staggered installation of can be achieved with preferable space tracking, the non-knuckle-tooth of sphere with mechanism in publication number CN103004346A Wheel is compared, and two degrees of freedom train of the present utility model is face gear, it is easy to process and make cost to substantially reduce, and being more suitable for should For production practices.

3rd, the utility model solves accurate rice pot seedling wide-and narrow-row transplanting mechanism in Application No. CN201310318352.7 and takes Seedling field offset amount is excessive, and the low problem of the seedling taking rate for causing, the transplanting arm of seven non-circular gear transplanting mechanisms has one in seedling taking The action of lateral shift, interferes with moving left and right for seedling case, and in actual production operation, seedling taking success rate is very low, and Box of tricks of the present utility model track in seedling taking is straight line, without transversal displacement, it is possible to achieve precisely seedling taking, is protected The success rate of card seedling taking.

4th, the utility model is adopted；By the pitch curve parameter and oblique gear spiral angle that optimize non-circular gear, can obtain The potted-seedling transplanting mechanism of the narrow plantation of accurate rice pot seedling one wide can be realized；With patent No. CN201510005090.8 and The pot seedling wide-and narrow-row mechanism mentioned in CN201510005883.X compares, the organization gear negligible amounts, structure it is simpler and It is compact, the reliability of mechanism is improve while production cost is reduced.

Description of the drawings

Fig. 1 is principle schematic diagram. of the present utility model.

Fig. 2 is the assembling schematic diagram of each gear in the utility model.

Fig. 3 is the side side view of each gear engagement states in the utility model.

Fig. 4 is the opposite side side view of each gear engagement states in the utility model.

Fig. 5 is lower middle helical gear of the present utility model and lower planet helical gear interlocks mesh schematic representation.

Fig. 6 is transplanting arm sectional view of the present utility model.

Fig. 7 is transplanting arm top view of the present utility model.

Fig. 8 is seedling taking process schematic of the present utility model.

Fig. 9 is that the utility model is realized transplanting the top view of track.

The transplanting effect diagram that wide-and narrow-row is transplanted is formed when Figure 10 is the utility model operation.

In figure：1st, transmission case, 2, final drive shaft, 3, drive bevel gear, 4, driven wheel of differential, 5, counter drive shaft, 6, actively Sprocket wheel, 7, central shaft, 8, chain, 9, center sprocket wheel, 10, differential driven gear, 11, differential driving gear, 12, gear-box, 13, Lower planet helical gear, 14, lower transplanting arm, 15, lower middle helical gear, 16, lower jackshaft, 17, lower middle non-circular gear, 18, in Heart non-circular gear, 19, upper middle non-circular gear, 20, upper jackshaft, 21, upper middle helical gear, 22, upper transplanting arm, 23, up Star helical gear, 24, upper planet axle, 25, lower planet axle, 26, cam, 27, spring, 28, spring base, 29, shift fork, 30, pushing sprout pole, 31st, transplant arm housing, 32, fixed block, 33, seedling taking intermediate plate, 34, U-shaped block, 35, seedling case, 36, alms bowl disk, 37, pot seedling, 38, transplant Track, 39, ground, m, seedling taking inlet point, n, seedling taking point, push away seedling point at t.

Specific embodiment

With reference to the accompanying drawings and examples the utility model is described in further detail.

As shown in Figure 1, Figure 2, Figure 3 and Figure 4, a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism, including biography Dynamic case 1, final drive shaft 2, drive bevel gear 3, driven wheel of differential 4, counter drive shaft 5, drive sprocket 6, central shaft 7, chain 8, in Heart sprocket wheel 9, two degrees of freedom train, upper transplanting arm 22 and lower transplanting arm 14；Final drive shaft 2, counter drive shaft 5 and central shaft 7 lead to Cross bearing to be bearing on transmission case 1, drive bevel gear 3 is fixed on final drive shaft 2, driven wheel of differential 4 and drive sprocket 6 are solid It is scheduled on counter drive shaft 5；Driven wheel of differential 4 is engaged with drive bevel gear 3；Center sprocket wheel 9 is fixed on central shaft 7, and with master Movable sprocket 6 is connected by chain 8；Two two degrees of freedom trains are symmetricly set on the two ends of central shaft 7.Power is by final drive shaft 2 Counter drive shaft 5 is delivered to, then Jing two degrees of freedom trains are delivered to transplanting arm 22 and lower transplanting arm 14.

As shown in Figure 1, Figure 2, Figure 3 and Figure 4, two degrees of freedom train include differential driving gear 11, differential driven gear 10, Gear-box 12, center non-circular gear 18, upper middle non-circular gear 19, upper middle helical gear 21, upper planet helical gear 23, lower centre Non-circular gear 17, lower middle helical gear 15 and lower planet helical gear 13, and by bearing be bearing in gear-box 12 it is upper in Countershaft 20, upper planet axle 24, lower jackshaft 16 and lower planet axle 25；Differential driving gear 11 is fixed on counter drive shaft 5；Differential The empty set of driven gear 10 is engaged on central shaft 7 with differential driving gear 11；Gear-box 12 stretches out transmission case with central shaft 7 Outer end is fixed by pin；Center non-circular gear 18 is fixed by dental inlay with differential driven gear 10；The non-knuckle-tooth in upper centre Wheel 19 and upper middle helical gear 21 are each attached on jackshaft 20；Upper middle non-circular gear 19 is nibbled with center non-circular gear 18 Close；Upper planet helical gear 23 is fixed on upper planet axle 24, and is engaged with upper middle helical gear 21；The lower He of middle non-circular gear 17 Lower middle helical gear 15 is each attached on lower jackshaft 16；Lower middle non-circular gear 17 is engaged with center non-circular gear 18；It is descending Star helical gear 13 is fixed on lower planet axle 25, and is engaged with lower middle helical gear 15.

The transplant arm housing 31 of upper transplanting arm 22 is stretched out the one end outside gear-box 12 and is fixed with upper planet axle 24, lower transplanting arm 14 transplant arm housing is stretched out the one end outside gear-box 12 and is fixed with lower planet axle 25, and upper transplanting arm and lower transplanting arm are arranged on tooth The same side of roller box；The cam of upper transplanting arm and lower transplanting arm is fixed with gear-box；Upper transplanting arm 22 and lower transplanting arm 14 Structure is identical, using ripe prior art, the such as patent of Application No. 201110164729.9.

As shown in Figure 1 and Figure 5, upper jackshaft 20 and lower jackshaft 16 are symmetricly set on the both sides of central shaft 7；In the middle of upper second Axle 26 and lower second jackshaft 17 are symmetricly set on the both sides of central shaft 7；During upper planet axle 24 and lower planet axle 25 are symmetricly set on The both sides of heart axle 7；Crossed axis angle between upper planet axle 24 and central shaft 7, lower planet axle 25 and central shaft 7 is Φ；Upper centre is oblique The helical angle of gear 21, upper planet helical gear 23, lower middle helical gear 15 and lower planet helical gear 13 is β；Φ=2 β；β roots The line-spacing transplanted according to wide-and narrow-row requires value.

As shown in Figure 2, Figure 3 and Figure 4, the pitch curve of center non-circular gear 18 is by cubic nonratio- nal B-spline curve fitting Into；Upper middle non-circular gear 19 is identical with the geometric parameter of lower middle non-circular gear 17, upper middle helical gear 21 with it is lower in Between helical gear 15 geometric parameter it is identical, upper planet helical gear 23 and the complete phase of the geometric parameter of lower planet helical gear 13 Together；The number of teeth of upper planet helical gear 23 is 2 times of the upper number of teeth of middle helical gear 21, and the number of teeth of lower planet helical gear 13 is lower centre 2 times of the number of teeth of helical gear 15.

As shown in Fig. 1, Fig. 8, Fig. 9 and Figure 10, the gearratio of drive sprocket 6 and center sprocket wheel 9 is 1, differential driving gear 11 are Knucle-gear with differential driven gear 10, and gearratio is 1, or for intermeshing non-circular gear；Transplanting mechanism seedling taking The seedling taking section of the transplanting track 38 that the cusp of intermediate plate 33 is formed is a line segment on top view, i.e., one section of track of m to n in figure Point-blank.

As shown in Fig. 1, Fig. 8, Fig. 9 and Figure 10, two degrees of freedom train is different from traditional single-degree-of-freedom planet circular system, center Non-circular gear and gear-box all can be rotated in mechanism's course of work, allow mechanism to realize free ratio characteristic；For reality The narrow requirement of line-spacing one wide of existing pot seedling wide-narrow row planting, the transplanting track 38 of the cusp of transplanting mechanism seedling taking intermediate plate 33 will meet shifting Cultivation process has certain side-play amount, and as shown in Figure 9 and Figure 10, transplanting arm offset distance △ D after seedling taking point n seedling takings are pushing away seedling Point t pushes pot seedling in soil, when Ji Tao mechanisms work simultaneously, can form the effect that rice shoot wide row and narrow row are alternately planted. During transplanting, in order to prevent the seedling taking action of transplanting arm from interfering with the traversing action of seedling case, it is ensured that on track 38 From seedling taking inlet point m to seedling taking, the transversal displacement of the seedling taking section of point n is as far as possible little, as shown in figure 9, of the present utility model two is free Degree train pot seedling wide-and narrow-row transplanting mechanism combines the gear characteristic of two degrees of freedom train and non-circular gear, makes the shifting of mechanism Plant m to n on track point-blank, without transversal displacement, to realize " straight seedling taking ".

The operation principle of the two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism is：

Power is delivered on driven wheel of differential 4 by the Jing drive bevel gears 3 of final drive shaft 2 in transmission case 1, drives auxiliary driving Axle 5 is rotated, and drive sprocket 6 drives center sprocket wheel 9 to rotate by chain 8, transfers power to central shaft 7, one end of central shaft 7 Fix with gear-box 12, drive gear-box 12 to rotate, meanwhile, counter drive shaft 5 drives differential driving gear 11 to rotate, and power is passed It is delivered to differential driven gear 10 of the empty set on central shaft 7；In gear-box 16, empty set on central shaft 7 with differential driven gear The 10 center non-circular gears 18 fixed are engaged respectively with upper middle non-circular gear 19, lower middle non-circular gear 17；Differential driven tooth Wheel 10 drives center non-circular gear 18 to rotate, then middle helical gear 21, upper planet helical gear 23 are delivered to transplanting arm 22 on Jing； Non-circular gear 17, lower middle helical gear 15, lower planet helical gear 13 are delivered to lower transplanting arm 14 in the middle of under Jing；Meanwhile, gear-box 12 rotate under the drive of central shaft 7, the gear train, upper transplanting arm 22 and lower transplanting arm 14 in the rotation drive case of gear-box 12 Rotate, two transplanting arms are simultaneously subject to be driven from the power of center non-circular gear 18 and the power of gear-box 12, due to two There is speed discrepancy in individual power, make transplanting arm realize differential rotation.

As shown in Figures 6 and 7, the rotation of transplanting arm swings the cam 26 that shift fork 29 is secured around on gear-box 12, Shift fork 29 is lifted through the ascent stage of cam 26 before seedling taking, and the pushing sprout pole 30 being connected with spring base 28 is pulled back, while logical The compression spring 27 of spring base 28 is crossed, the U-shaped block 34 being welded on pushing sprout pole is also moved rearwards by with pushing sprout pole, extruding seedling taking intermediate plate 33 (seedling taking intermediate plate 33 is fixed in transplant arm housing by fixed block 32), makes two intermediate plates close and clamp rice shoot, completes seedling taking Action；From after seedling taking to pushing away before seedling, shift fork 29 is in the extreme higher position maintaining segment of cam 26；When transplanting arm is reached pushes away seedling point t, Shift fork 29 goes to the reverse-running section of cam 26, and the return of spring 27 promotes pushing sprout pole 30 and U-shaped block 34 quickly to move forward, seedling taking intermediate plate 33 open under natural resiliency, unclamp pot seedling, and pushing sprout pole pushes the native alms bowl of pot seedling 37 in the soil on ground 39, complete to push away seedling and move Make.Due between upper planet helical gear 14 and center non-circular gear 18 and between lower planet helical gear 6 and center non-circular gear 18 Crossed axis angle Φ be not zero, therefore the rotational plane of upper transplanting arm 22, the rotational plane of lower transplanting arm 14 and gear-box 12 is uneven OK, after causing seedling taking intermediate plate 33 in the transplanting arm seedling taking point n on the alms bowl disk 36 of seedling case 35 to take pot seedling 37, offset distance laterally △ D push away seedling to seedling point t is pushed away, and the mechanization wide-and narrow-row for being achieved in accurate rice pot seedling is transplanted.

Claims (7)

1. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism, including transmission case, final drive shaft, drive bevel gear, Driven wheel of differential, counter drive shaft, drive sprocket, central shaft, chain, center sprocket wheel, two degrees of freedom train, upper transplanting arm and move down Plant arm, it is characterised in that：Described final drive shaft, counter drive shaft and central shaft are bearing on transmission case by bearing, actively Bevel gear is fixed on final drive shaft, and driven wheel of differential and drive sprocket are each attached on counter drive shaft；It is described from mantle tooth Wheel is engaged with drive bevel gear；Center sprocket wheel is fixed on central shaft, and is connected by chain with drive sprocket；Two two freely Degree train is symmetricly set on the two ends of central shaft；

Described two degrees of freedom train include differential driving gear, differential driven gear, gear-box, center non-circular gear, it is upper in Between non-circular gear, upper middle helical gear, upper planet helical gear, lower middle non-circular gear, lower middle helical gear and lower planet helical teeth Wheel, and the upper jackshaft in gear-box, upper planet axle, lower jackshaft and lower planet axle are bearing in by bearing；Described difference Fast driving gear is fixed on counter drive shaft；Differential driven gear empty set on center shaft, and is engaged with differential driving gear；Tooth The end that roller box stretches out outside transmission case with central shaft is fixed by pin；Described center non-circular gear by dental inlay and differential from Moving gear is fixed；Upper middle non-circular gear and upper middle helical gear are each attached on jackshaft；Upper middle non-circular gear is with Heart non-circular gear is engaged；Upper planet helical gear is fixed on upper planet axle, and is engaged with upper middle helical gear；The non-knuckle-tooth in lower centre Wheel and lower middle helical gear are each attached on lower jackshaft；Lower middle non-circular gear is engaged with center non-circular gear；Lower planet is oblique Gear is fixed on lower planet axle, and is engaged with lower middle helical gear；

One end that the transplant arm housing of described upper transplanting arm goes out outside gear-box with upper planet shaft extension is fixed, the transplanting of lower transplanting arm One end that arm housing goes out outside gear-box with lower planet shaft extension is fixed, and upper transplanting arm and lower transplanting arm are arranged on the same of gear-box Side；The cam of upper transplanting arm and lower transplanting arm is fixed with gear-box；Upper transplanting arm is identical with the structure of lower transplanting arm.

2. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism according to claim 1, it is characterised in that：Institute The upper jackshaft and lower jackshaft stated is symmetricly set on central shaft both sides；Described upper planet axle and lower planet axial symmetry is arranged on Central shaft both sides, the crossed axis angle between upper planet axle and central shaft, lower planet axle and central shaft is Φ；Upper middle helical gear, Upper planet helical gear, lower middle helical gear and the helical gear helical angle of lower planet are β；Φ=2 β；β is transplanted according to wide-and narrow-row Line-spacing requires value.

3. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism according to claim 1, it is characterised in that：Institute The pitch curve for stating center non-circular gear is formed by cubic nonratio- nal B-spline curve fitting.

4. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism according to claim 1, it is characterised in that：Institute The geometric parameter for stating middle non-circular gear and lower middle non-circular gear is identical, upper middle helical gear and lower middle helical gear Geometric parameter it is identical, upper planet helical gear is identical with the helical gear geometric parameter of lower planet；The upper planet is oblique The number of teeth of gear is 2 times of the upper middle helical gear number of teeth, and the helical gear number of teeth of lower planet is 2 times of the lower middle helical gear number of teeth.

5. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism according to claim 1, it is characterised in that：Institute The gearratio for stating drive sprocket and center sprocket wheel is 1.

6. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism according to claim 1, it is characterised in that：Institute The differential driving gear and differential driven gear stated is Knucle-gear, and gearratio is 1, or for intermeshing non-circular gear.

7. a kind of two degrees of freedom train accurate rice pot seedling wide-and narrow-row transplanting mechanism according to claim 1, it is characterised in that：On The seedling taking intermediate plate cusp of transplanting arm or lower transplanting arm formed transplanting track seedling taking section in the horizontal plane be projected as one Straightway.