the preferred embodiment of the farm implement of the invention , as shown in fig1 comprises an implement carrier frame 1 on which is pivotally attached a rockshaft 2 at first pivot 5 . wheels shown at b support the carrier frame above the ground . a tool gang frame 3 is also attached to the rockshaft 2 at second pivots 6 . a ground engaging rear depth control arm 4 is attached to the rear of the tool gang 3 at pivots 7 . fig1 shows a side elevation of the implement in its lowermost or first position . tool gang frame 3 is disposed parallel to the ground a and is freely rotatable about and supported front and back by first and second pivot axes 6 and 7 respectively . a plurality of ground working tools may be mounted on the tool gang frame for working at variable depths generally parallel to the surface of the ground a . a rockshaft 2 is mounted to carrier frame 1 for rotation about pivot axis 5 . the angular position of the rockshaft 2 is controlled by a hydraulic cylinder d shown fully retracted with the rockshaft 2 generally horizontal in fig1 . a flange 3 on tool gang frame 3 extends downward and provides pivotal support for tool gang frame 3 about axis 6 . a tool support arm 4 is pivotally attached at pivot axis 7 to support tool gang frame 3 at the rear and may carry an additional soil working tool c . [ 0061 ] fig2 shows a side elevation of the implement upon partial extension of the hydraulic cylinder d to a second position at which rotation of the tool gang frame 3 about pivot axis 6 ceases when abutment f contacts tool gang frame 3 at abutment point g . in the configuration shown in fig1 the rear of tool gang frame 3 is supported by the control arm 4 . at the second position shown in fig2 the working tools may be elevated above the ground . [ 0062 ] fig3 shows a side elevation of the implement upon further extension of cylinder d to move the rockshaft to a third position . between the second position shown in fig2 and the third position shown in fig3 rotation of the tool gang frame 3 about second pivot axis 6 is restrained . additionally , frame 3 rotates in conjunction with rockshaft 2 about first pivot axis 5 , is supported on rockshaft 2 , and is free of the ground . at the third position as shown in fig3 tool gang frame roller j contacts curved track i mounted on carrier frame 1 . as shown in fig4 further extension of cylinder d rotates rockshaft 2 about the first axis 5 to a fourth position . between the third position and the fourth position , the roller j interacts with curved track i to continue rotation of the tool gang frame 3 about the second axis 6 and moves the abutment f out of contact with the abutment point g . referring now to fig5 the carrier frame 1 is preferably arranged as a pair of wings symmetrical about the implement center line 308 for travel in direction a . each of the 2 wings is pivotally attached to the central telescoping hitch 301 for motion about a vertical axis at 305 . the carrier frame 1 is supported on transversely spaced pairs of wheels b . the rockshaft 2 shown in fig1 - 4 is not shown on fig5 - 6 for simplicity . a plurality of tool gang frames 3 and support arms 4 are shown . support tools c are represented schematically . draft arms 303 connect each wing section as at pivotal attachment 304 on frame 1 to telescoping hitch 301 at pivot point 302 . as can be seen in fig5 a , 5 b , and 6 , the carrier frame 1 is folded forward symmetrically by extension of telescoping hitch 301 . the hitch 301 is extended in length in each successive figure . a pair of secondary draft or hitch members 309 is pivotally attached to hitch 301 at 302 and extends rearwardly towards secondary hitching point 307 . mounted between members 309 and hitch point 307 are rear hitch members 313 which are pivotally connected between pivot points 312 and 314 for rotation about vertical axes . pivot points 312 are also connected to support arms 310 extending from each hitch member to a respective frame section for pivotal movement as at 311 . as can be seen in fig5 a secondary hitch is provided to which another implement may be attached as at 307 for operation in the direction of travel a . the draft load of the second implement is supported on hitch members 309 and 313 along with support arms 310 which act to maintain hitch members 309 and 313 separated from the implement center line 308 . as telescoping hitch 301 is extended and the wings are folded forward as shown in fig5 a , the distance b between pivots 305 and hitch point 307 is substantially shortened . as telescoping hitch 301 is further extended and the wings folded to the direction of travel a , the distance b is minimized , thereby bringing the second implement in close proximity to carrier frame 1 for stability in transport . in fig6 a schematic elevation of the preferred embodiment is shown in which the secondary hitch members 309 , 310 and 313 are above carrier frame 1 . referring now to fig7 through 9 , the preferred embodiment will be described in relation to depth adjustment . fig7 and 8 correspond generally to fig1 and 2 , respectively . fig9 is a side elevation intermediate the second and third rockshaft positions . at another point 13 on the rockshaft , offset from the tool gang pivot 6 , a depth control link 12 is pivotally attached . the depth control link is attached at end 14 to a first end of a depth control lever 8 . the lever is pivotally attached to the rear part of the tool gang frame 3 at an intermediate point between its ends . a roller 10 is attached to the lever &# 39 ; s second end . the implement depth control 4 consists of an arm 21 which is pivotally attached at one end 7 to a rear part of the tool gang frame 3 and has ground engaging wheels 23 pivotally attached at its other end having a generally transverse axis 20 . in the field position , roller 10 is in contact with the upper surface 22 of the support arm 21 and the support arm thereby supports the rearward part of the tool gang frame . this in part controls the depth of the tool gang frame as the ground wheels follow the surface of the ground . in field positions , the tool gang frame 3 may pivot on attachment pivot 6 as ground wheels 23 and ground wheels 24 follow the slope of the ground . the tool gang is supported parallel to the ground between the frame ground wheels and depth gage ground wheels . a screw connects the depth control link to the depth control lever . the screw may be utilized to adjust the effective length of the depth control link for leveling the tool gang frame . each tool gang frame may thereby be independently leveled . alternatively , a turnbuckle or similar length adjusting means may be used in the depth control link . the rockshaft 2 of respective frame sections is rotated clockwise or counterclockwise as shown in the view in fig7 and 8 to respectively lower or raise the attached tool gang frame sections . the depth control link 12 is drawn forward relative to the tool gang frame 3 when the rockshaft is rotated counterclockwise to raise the tool gang frame . the depth control link causes the depth control lever 8 to rotate clockwise in the view of fig8 and the roller on its second end bears down on the depth control support arm 4 , thereby causing rotation of the depth control in a clockwise direction . the attachment points of the linkage on the rockshaft and on the depth control lever are such that the rear depth control is rotated an amount causing an equal rise at the rear of the tool gang when the rockshaft raises the front of the tool gang as shown in fig7 and 8 . the preferred embodiment will now be described in respect of its spiral guide in conjunction with fig1 through 14 . the spiral guide 60 is made to have an axis generally concentric with the pivot 7 by which packer arm 21 is attached to tillage gang frame 3 . the packer arm has a spindle 71 extending its pivotally connected end on which a roller 70 is secured . the spiral guide 60 has a non - spiral surface 61 which the roller 70 follows when the implement is in the field position , and which restricts the sideways movement of the packer arm on the pivot shaft 7 , as shown in fig1 - 15 . as the implement is folded to the transport position as shown in fig1 - 15 , the roller 70 leaves the non - spiral surface 61 and follows the angled or spiral surface 62 . the roller 70 is limited by opposing spiral surface 63 . as the packer pivots downwardly from the end of the tool gang frame 3 or tillage gang , the roller is caught in a track formed between the spiral surfaces 62 , 63 . . the spiral shape is such that the controlled movement causes a sideways or lateral offset 69 of the packer elements as the packer is suspended and rotates downwardly when being raised to the transport position . the spiral surfaces 62 , 63 control the roller movement and cause the packer to return to alignment with the tillage elements when lowered into the field position . referring now to fig1 and 17 , it is shown that the preferred embodiment may include a spring pressure mechanism to transfer weight to the tool gang frame 3 . in fig1 and 17 , the spring 50 may be pre - compressed by selectively shortening the available stroke of rod 51 , such as by a nut and tread on rod 50 . this provides of a large unsprung range of rotation between the first and second positions while providing the operator with additional adjustments . in particular , as shown in fig1 , the tool gang frame 3 is depicted in its first position , the lowermost position , as viewed in fig1 . spring 50 acts between frame 3 and rod 51 to advantageously transfer weight to the frame . the spring is adjustable by lengthening or shortening the rod 53 . arm 52 acts between rod 51 and rockshaft 2 and is pivotally attached to provide for abutment of rod 53 , as at 54 in fig1 . in the second rockshaft position , the highest field position , rod 53 loses abutting contact as at 54 in fig1 and rod 51 is fully retracted by spring 50 . as shown in fig1 - 20 c , automatic locking is provided by means of levers connected between the frame position control cylinders shown in fig1 . the control cylinders have a limited degree of freedom of movement between the lever and the frame and the cylinders actuating movement . interconnection of the lever with locks provides for automatic operation of the locks at the two extents of the cylinders &# 39 ; extension as shown so as to not interfere with extension and contraction of the cylinders and corresponding frame movement . referring now to fig1 and 20 , the implement is shown with inner wings w 1 and outer wings w 2 symmetrically joined along the implement center line for pivotal relative motion between wings w 1 and w 2 about an axis generally in the direction of travel when in the field working position . [ 0078 ] fig2 shows the implement in the position shown in fig3 and fig2 shows wheels b as item 24 for castering about a vertical axis at 25 with extending arm 26 in the field working position . item f is referred to as 15 in fig2 - 23 b . [ 0079 ] fig2 , and in more detail in fig2 a , the transport condition with wheels 24 fully castered about axis 25 and arm 26 locked in position by plate 27 is shown . fig2 b shows the arm 26 in recess in plate 27 . [ 0080 ] fig2 shows the implement in the position of fig1 . outer wing section w 2 is pivotally joined to inner wing section w 1 at forward and rearward points 51 and 52 respectively . in fig2 a , angled wing axis 53 is depicted as inclined downward and forward in the direction of travel a by amount dd . fig2 b shows a partial plan view of inner wing section w 1 and outer wing section w 2 along with forward and rearward members w 1 a and w 1 b of inner wing w 1 . fig2 c shows a partial rear elevation of fig2 b .
a forwardly folding tillage implement carries a number of ground engaging tools on a tool gang frame disposed to the rear of a carrier frame . a rockshaft is disposed between the carrier frame and the tool gang frame and is movable between four rotated positions about two axes of rotation . a control mechanism controls the relative angular position of the rockshaft . a support mechanism is disposed rearwardly of the axes of rotation to support the rear of the tool gang frame above the ground in the field working position . an abutment member restrains the relative rotation between the rockshaft and the tool gang frame to fully support the tool gang frame on the rockshaft upon rotation of the rockshaft . an offset cam is operatively connected between the carrier frame and the tool gang frame to provide translational movement of the packer members on the tool frame relative to the tillage tools on the carrier frame to shift the packer members out of alignment with the tillage tools so that their elements do not impact upon folding to the transport position .