'at3~33~ s This application is a division of Canadian Serial No. 293,280, filed December 16V 1977.
TRAILING TANDEM MOWER

BACKGROUND OF THE INVENTION
A tandem mower is desired that includes all of the advantages of a single mower but with the double-cutting capacity. The mower should have cutting bars which can float above and below the hor~zontal to follow the contour oE the ground and can be readily raised through operation of a power means to a first position with both the inner and outer shoes off of the ground and then to a second position for transporting of the mower with the cutter bar in a vertical position.
This should be accomplished with a single power cylinder.
The mower should further be readily adapted for being positioned for cutting or for transport. The mower section should also have breakaway capability such that upon the cutting bars hitting an obstruction they will pivot rearwardly but should be allowed to continue to operate in the breakaway position.

SUMMARY OF T~E INVENTION
; In accordance with the present invention a tandem mower is provided that allows for a single power cylinder assisted by a spring to pivot the cutting bar on a frame~arm to a position with the inner and outer shoes above the ground and continued operation of the power cyllndler unassisted by the spring pivots only the 30 ~ cutting bar to a vertical transport position~ The ~::

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cutting bar in its cuttincJ position is free to float above and below the horizontal a~ much as 45.
Cutting bars of 7 or 9 feet provide an effec-tive cutting swath oE 14 or 18 feet, thu~ requiring a long frame since the cutting bars are also rearwardly pivotable to breakaway positions upon encountering obstructions and thus the second mower must be rear-wardly spaced sufficiently to allow the front cutting bar to pivot rearwardly. The width of the mower imple-ment is substantial and obviously does not followdirectly behind the tractor. Steerable support wheels are provided on the mower at the rear end which may be turned to move the mower onto the centerline behind the tractor for transport. A power cylinder operated from the driver seat is provided for moving the mower between cutting and transport positions.
The tractor may be turned 90 to the centerline of the mower without binding the power takeoff drive due to the fact that a pair of universal joints are provided on the trac~or and on the mower at an equal dis~ance from the pivot connection between the tractor drawbar and the mower tongue whereby a 90 angle between the centerline of the tractor and the centerline of the mower produces only a 45 angle between the power takeoff drive shaft connecting the tractor power takeoff to the uni-versal joint on the mower.
Severe strain on the drive shaft connected to the rear mower is eliminatad when in the breakaway position thereby allowing it to continue to operate due to the fact that the laterally extending drive ~haft is made extendable and is connected to a gear box on the second

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mower which is pivotal with the second mower when itpivots to its breakaway position.
The mower of this invention is capable of being quickly attached and disattached from the tractor, thereby freeing the tractor up for other uses.

DESCRIPTION OF THE DRAWINGS
Figure 1 is a fragmentary top plan view of the trailing tandem mower oE this invention showing the mower in its c~tting position.

Figure 2 is a side elevation view thereoE taken along line 2-2 o Figure 1.
Figure 3 is an enlarged in scale side elevation view of the non-binding power take-off drive shaft extending from the tractor power take-off to the univer-sal joint on the tongue of the mower taken along line

3-3 in Figure 1.
Figure 4 is a top plan view thereof showing the tractor turned 90 to the mower with the power take~
off drive shaft extending at 45 to the mower and drawbar.
Figure 5 is a top plan view similar to Figure 1 but showing the mower moved by ~he steerable wheels to the transport position ollowing directly behind the tractor.
Figure 6 is an elevational view taken along line 6-6 in Figure 1 and illustrating the steering mechanism.

Figures 7 and 8 are top plan views oE the second mower in the cutting and breakaway positions.
Figure 9 is an enlarged fragmentary perspective view of the :Lift mechanism.
~ Figure 10 is a cross-sectional view taken along :;:

.?3315 line 10-10 in Figure 9 and showing the mower in its cutting position.
Figure 11 is a cross-sectional view taken along line 11-11 in Figure 10.
Figure 12 is a view similar to Figure 10 but showing the mower in a raised position with the inner and outer cutting bar shoes raised off the ground.
Figure 13 is a cross-sectional view taken along line ]3-13 in Figure 12.
Figure 14 is a view similar to Figures 10 and 12 but illustrating the cutting bar in its raised trans-port position.
Figure 15 is a cross-sectional view taken along line 15-15 in Figure 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT
The trailing tandem mower of this invention is referred to generally in Figure 1 by the reference numeral 10 and is shown being pulled by a tractor 12 having a drawbar 14. Front and rear sickle bar type mower units 16 and 1~ are mounted on an elongated frame 20 having rear steerable support wheels 22.
The steerable wheels feature of this invention is illustrated in Figures 1 and 5 and allows for a pair of side-by-side swaths 24 and 26 to be cut by cutter bars 28 and 30, respectively, when the mower 10 is in its cutting position, as shown in Figure 1. When tha mower is in its transport position, as shown in Figure 5,~ it trails directly behind the tractor l2 and the cutter bars 28 and 30 are in their raised transport vertical positions. In the cutting position of Figure ~33~i 1, the cutter bars 28 and 30 extend perpendicular to the line of travel of the tractor and mower while in Figure 5, in the transport position, the longitudinal axis of the bars 28 and 30, when in their horizontal positions, would be substantia].ly rearwardly of the right angle position of Figure 1.
The steering mechanism is shown in detail in Figures 6-8 and shows the wheel.s 22 being mounted on axles 32 pivotal in a horizontal plane about an axis 34 in response to actuation from tie rods 36 and 38 extending in opposite directions from the center of the mower frame 20 and under an axle 40. The rods 36 and 38 are interconnected at 42 and rod 33 is connected to the lower end 44 of an actuating lever 46 operated by a power cylinder 48 which is capable of moving the lever 46 between the solid and dashline positions illustrated in Figure 6. Operation of the power cylinder 48 may be accomplished from the seat of the tractor 12. The nor-mal trailing path for the mower 10, if the wheels were freely pivotal, would be somewhere between the paths shown in Figures 1 and 5, and perhaps closer to the line of travel shown in Figure 1 with the mower in its cuttiny position.
The power takeof~ drive system for the mower allows for unrestricted turning of the tractor 90D relative to the mower without binding the power takeoff drive shaft, as seen in Figures 2-4, and allows for the mowers 16 and 18 to pivot out of the cutting position illus-trated in the solid lines in Figure 1, and move to a ; 30 breakaway position, as illustrated by the dash lines upon the cutter bars 28 and 30 hitting an obstruction.

Continuous operation of the cutter blades is permissible _5_ 33~

due to the drive sha:Et arrangement and design.
Referring now to Figures 2-4, it i5 seen that a power takeoff drive 50 on the tractor 12 is connected to a universal joint 52 on the tongue 54 of the ~ower 10 by an extendable drive shaft 56. The tongue 54 is pivotably connected to the drawbar 14 through a ball-type coupling 58 and is spaced a distance X from the U-joint 52 on the tongue 54 ancl is spaced the same distance X from the connection between the drive shaft 56 and the drive unit 50 on the tractor 12. Accordingly, as seen in Figure 4, when the tractor 12 is turned 90 to the implement tongue 54, the angle between the drive shaft 56 and the implement tongue and the drawbar 14 is 45, thus cutting in half the strain that would other-wise occur on the drive shaft 55 and the universal joint couplings.
In Figures 1-8 the remaining portions of the drive system for operating both mowers 16 and 18 from the power takeoff drive unit 50 on the tractor 12 is shown to include a drive shaft 60 connected by a coupling unit 62 on the tongue 54 to a gear box 66 connected to the fron~ mower 16 which in turn is connected to a drive shaft 68 connected to a gear box 70 laterally offset from the mower unit 18 at the rear of the implement. A laterally extending drive shaft 72 having telescopic portions 74 and 76 extends from the gear box 70 to a gear box 78 on a support stand 80 carried on the mower unit 18 which is pivotally connected to frame assembly 82 for pivotal movement about an axis 84, as seen in Figure 8, to allow the ; mower unit 18 to pivot between the cutti.ng position 3~

of Figure 7 and the breakaway position of Figure 8.
A short drive shaft 86 extends rearwardly from the gear box 78 to the cutter bar drive pulley assembly 88~ It is seen when the mower unit 18 pivots from the cutting position of Figure 7 to the breakaway position of Figure 8, the transversely extending drive shaft 72 extends and contracts through operation of the t~les-coping sections 74 and 76 thereby allowing the shorter drive shaft 86 to retain its same length throughout the pivoting operation. The mower cutter bar 30 may continue to be operated in the breakaway position of Figure 8 since the angle betwe~n the drive shaft 72 and the gear box 78 is not so great that it impairs operation. The telescoping sections 74 and 76 are sufficiently long to allow the necessary telescoping action as the mower pivots between the two positions.
The lifting mechanism for each of the mowers 16 and 18 is substantially the same but is illustrated in detail relative to the front mower 16 in Figures 9-lS. Basically, the cutter bar 28 is movable by a single acting hydraulic cylinder ~0 assisted by a spring 92 between a cutting position, as seen in Figure 10, and a raised cutting position, as seen in Figure 12, followed by a transport position, as seen in Figure 14 wherein the cutter bar 30 is in a vertical position having been pivoted thereby the power cyllnder 90 without the assistance of the spring 92. The cutter bar 30 is free to float in the cutting position of Figure 10 as much as 45 above and below the horizontal due to the unique lifting and raising mechanism employed.

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Hydraulic fluid is introduced .into the cylinder 90 through a line 94 and an air vent 96 is provided at the opposite end.
The mower frame 20 includes downwardly extending frame members 97, as seen in F:igure 9, connected to a conventional breakaway release mechanism 98 which provides for pivotal movement about an axis 8~ for pivotal movement between the positions shown in Figures 7 and 8, and in the solid and dash lines i.n Figure 1.
The cutter bar gear box 100 is pivotally connected to a frame arm 102 for pivotal movement about a pin 104 extending between spaced apart arm members 106 and 108.
The arm 102 is pivotally connected to the release mechanism for pivotal movement about an axis 110. The arm member 106 is integral with a curved upstanding arm portion 112 and is free to move between the downwardly extending position of approximately 45 below the horizontal to an upward position wherein it engages leaf springs 114 which yieldably limit further upward pivot-ing action of the arm assembly 102 only, A pair of upstanding members 116 and 118 are pivotally connected to the frama arm assembly 102 by a pin 120 with the member 118 being connected to the outer end of the hydraulic cylinder 90. The inner end of the cylinder 90 :is connected to a stationary mounting bracket : 122 mounted on the release mechanism 98.
The cutter bar gear box 100 is connected by a link 124 to the upstandillg member 116 which moves in unison with the member 118 and in turn is connected by a link 126 to a V-shaped pivotal element 128 pivotally connected . . , '33~

to the upper end of the curved member 112 for pivotal movement about an axis 130. The rod 126 includes a lost-motion connection 132 adapted -to provide actuating forces in tension only since as seen in Figure 14, when the mower is in its raised position the rod 126 extends through the coupling 132 and is limited in its movement in the opposite direction by nuts 134. The opposite leg 140 of the V-shaped element 128 is connected by a link 142 to a three~finger rotatable wheel element 144 rotatably mounted on a post 146. The opposite side of the wheel element 144 is connected to the spring 92 which is anchored at 148 on the frame arm assembly 102.
Thus the lifting mechanism in operation functions as follows referring to Figures 9-15. Hydraulic cylinder 90 is contracted and is assisted by the spring 92 and raises the cutter bar at both its inner and outer ends to the position of Figure 12 wherein the outer end is approximately 32 inches off the ground with the inner end being approximately 16 inches off the ground. At this point the spring 92 is substantially inoperative and further operation of the power cylinder 90 serves only to pivot the cutter bar 28 to the vertical position of Figure 14 by the member 118 through the link 124 pivoting the cutter bar 28 to the vertical position. Further, pivoting motion of the cutter bar 28 is limited by a stop 150 on t:he frame arm member 106 adjacent the upstanding e]emQnt 116.
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