referring now to fig1 - 4 , there is disclosed a planter 10 connected to a drive vehicle ( not shown ) which would be situated to the left as the planter is viewed in fig1 - 4 . as seen in fig3 and 4 , a frame member 12 extends between a draft tube 15 and the drive vehicle . the frame 12 may take the form of a generally rectangular frame member in which two struts 12 form a triangle with the apex of the triangle meeting at the connection point of the frame to the drive vehicle or tractor with the third member being positioned underneath it . this connection to the tractor is well known in the art and may take a variety of forms but is represented by the frame member 12 . the draft tube 15 extends in use laterally to the direction of travel of the agricultural implement 10 and is in the form of a hollow tube having a front side 16 , a rear side 17 , and top and bottom 18 and 19 , respectively . when the front of an apparatus is referred to herein , it is meant the portion of the apparatus toward the drive vehicle or tractor . row units 25 a and 25 b and thus seen in fig1 - 3 are laterally spaced apart along the draft tube 15 , the row units 25 a being generally placed for wide spaced crops such as corn , for instance at 30 ″ center to center , while the row units 25 b are likewise arranged and positioned intermediate row units 25 a . therefore , when all row units 25 a and b are being simultaneously used , the crops will be planted at 15 ″ spacing , whereas when only alternate row units are used , then the crop will be planted at 30 ″. referring now to fig1 - 3 , the row units 25 a and b are identical in structure , the only difference being in the frame structure mounting the row units to the draft tube 15 . each row units 25 a and b has cradle structure 26 including opposed side panels 27 and end panels 28 . further , each row unit 25 includes a hopper 30 and a lid 31 . the designation a and b is used to indicate alternate row units with row units 25 a being indicated as row unit 1 for purposes of illustration , whereas unit 2 is indicated as 25 b . it being seen from the drawings that the b units are spaced rearwardly of the a units in use , the extent to which may be adjusted , as will be described . further , each of the row units 25 a and b include a shank 35 extending downwardly and generally parallel to the draft tube 15 and supports the cradle 26 . a rearwardly extending shank 36 extends from the shank 35 to provide frame work on which are mounted spaced apart gauge wheels 40 , openers 41 with associated scrapers 42 and closers 45 mounted on frame member 47 by means of a pivot shaft 46 . the gauge wheels 40 , openers 41 , and closers 45 are all standard farm implements and well known in the art . standard parallel linkage 50 connects the row units 25 a and b to the draft tube 15 and includes upper and lower linkages 51 and 52 respectively with apertures 53 being in the upper links 51 and apertures 54 in the lower links 52 . linkage 50 is noted with a capital a or capital b depending on which row unit 25 a or 25 b the linkage 50 serves to connect to the draft tube 15 . as seen , the row units 25 a are mounted to the front side 16 of the draft tube 15 while row units 25 b are mounted to the rear side 17 of the draft tube 15 . referring particularly to fig1 and 5 - 7 , the linkage 50 and mounting mechanism for the row units 25 a are illustrated . the linkage 50 a connects the row unit 25 a to a vertically extending angle iron 60 a . the angle iron 60 a has flanges 61 a and 62 a perpendicular to each other with flange 62 a extending from just above the top of the draft tube 15 to well below it and mounted to the front side 16 . another angle iron 65 a is positioned with perpendicular flanges 66 a and 67 a to the rear of the angle iron 60 a and more particularly the sides 62 a and 66 a are connected by suitable bolts 76 as seen in fig7 . the links 50 a including the upper links 51 a and lower link 52 a are connected to the angle irons 65 a by suitable bolts 79 and to the row units 25 a at the cradle side 27 by bolt 81 and to the shank 35 by bolt 81 . as may be seen from the drawings , particularly fig5 and 7 , the parallel linkages 50 a and the angle irons to which they are connected , are mounted to the front side 16 of the draft tube 15 by means of spaced apart bolts 75 secured by appropriate fasteners 76 . therefore , although the row units 25 a extend rearwardly of the draft tube 15 , the row units 25 a are mounted to the front side 16 of the draft tube . referring specifically now to the aforementioned drawings and fig3 it is seen that row units 25 b are also connected to the draft tube 15 and extend rearwardly but the row units 25 b are connected to the rear surface or side 17 of the draft tube 15 . angle irons 60 b are provided and are similar or identical to the angle irons 60 a having flanges 61 b and 62 b . for each row unit 25 b , there is extra hardware provided in the form of an angle iron 65 b which corresponds to the previously described angle iron 65 a and is spaced from the angle iron 60 b by a third angle iron 65 c . angle iron 65 c is connected to angle iron 65 b by a series of bolts 72 while the angle iron 67 b is connected to the associated linkage 50 b by means of bolts 79 . a strengthening member 69 b connects angle irons 60 b and 65 c . [ 0025 ] fig3 and 4 particularly show the support wheel assemblies 85 which are connected by means of a support member 86 extending downwardly from the draft tube 15 , the support member 86 having a top portion 87 , from which hangs a hydraulic cylinder 90 . hydraulic cylinder 90 is mounted to support member 86 by means of a upper pivot pin 91 , the hydraulic cylinder 90 having a piston 92 connected to a pivot 93 on a linkage 95 connected to the support or drive wheel 100 as at stub shaft or axle 101 . fig3 illustrates the support or drive wheels 100 in the working or field position in which the gauge wheels 40 and associated openers 41 and closers 45 are also in contact with the ground as seed or other material are introduced into the field . by extending the piston 92 of the hydraulic cylinder 90 with standard hydraulic mechanisms connected to the tractor ( not shown ), the frame 12 along with the associated mechanism including all of the row units 25 a and 25 b are elevated off the ground either at the end of a row when the planter 10 must be turned or when the planter 10 is being hauled along the road . several aspects of the present invention are of considerable importance , the first being that all of the row units 25 a and 25 b are positioned to the rear of the draft tube 15 . as seen in the drawings , the row units 25 a are rearwardly staggered with respect to the row units 25 b . row units 25 b extend further rearwardly than the row units 25 a , thereby facilitating maintenance , access to the hoppers 30 and preventing trash build - up between the adjacent row units and particularly the gauge wheels 40 thereof . the extent to which row units 25 a and b are staggered may be varied depending on the structure of the angle irons 60 b , 65 b and 65 c . as before stated in the background of the invention , no till farming has increased the amount of trash present in many fields and staggering the row units 25 a and 25 b alleviates a serious trash problem . an additional feature of the present is the location of the support or drive wheels 100 forward of the draft tube 15 thereby providing substantial room to the rear of the draft tube for the row units 25 a and b . although discussed hereinbefore that the row units 25 may be placed on 30 ″ centers , it is clear that a variety of spacings may be useful in the present invention . another important aspect of the present invention is that in the field or working position as illustrated in fig3 the bottom of the draft tube 15 is preferably no less than 31 ″ above the ground as compared to the usual frame height of about 21 ″. the additional vertical room obtained by raising the frame members an extra 10 ″ above the ground permits the row units 25 a and b to be located rearward of the draft tube 15 and all the linkage 50 therefore positioned below the draft tube . the wheels 100 have to be forward of the draft tube 15 as in the present construction , there is no room for them to the rear of the draft tube as is common practice . movement of the support wheel assemblies 85 including the associated mechanism forward of the draft tube 15 also moves the center of gravity of the unit forward using pivot 94 as a fulcrum when the unit is elevated to the transport position as shown in fig4 . by elevating the frame , the linkage 50 , at least for the row units 25 a , can pass underneath the draft tube 15 still permitting the planter 10 to move up and down through the field as required . the linkage 50 for the row units 25 b are also positioned below the draft tube 15 but do not extend beneath the draft tube . while particular embodiments of the present invention have been shown and described , it will be appreciated by those skilled in the art that changes , modifications and improvements may be made , for example in the processing of the materials or in the electrode and / or cell design without departing from the true spirit and scope of the invention .
an agricultural implement with an elongated bar having a front side nearer in use to a drive vehicle and a rear side . a first plurality of row units are laterally spaced apart along the bar and extend rearwardly thereof connected through parallel linkage to the front side of the elongated bar . a second plurality of row units are laterally spaced apart along the bar and extend rearwardly thereof interleaved with the first plurality of row units and connected through parallel linkage to the rear side of the bar . parallel linkage for both the first and second plurality of row units is directly mounted to and extends rearwardly of and below the bar to position all row units to the rear of the bar , allowing both field crops or row crops to be planted .