referring to fig1 a general description of a bale wagon with which the instant invention may be advantageously employed will be given . bale wagon 10 comprises a main frame 11 extending from the rear toward the front of the wagon , terminating in a tongue 12 adapted to be affixed to a tractor or similar vehicle . the frame 11 is supported rearwardly by a pair of opposing wheels , only one of which , 13 , is shown . a bale - receiving area 14 comprises a table - like surface 15 ( see fig2 ) upon which bales are serially deposited by conventional loader 16 . a cross conveyor 17 having flights space therealong engages the bales as they are loaded and moves them in line toward the opposing end of surface 15 . an elongate pusher mechanism 19 extends transversely of surface 15 and , through the actuation of cylinder 31 and ram 32 ( best seen in fig2 ) traverses the surface 15 to engage bales thereon and moves them rearwardly . a bale - accumulating surface 21 , comprised of a table 22 is positioned rearwardly of and adjacent the bale support area 14 . table 22 is pivotable about the rear end thereof in a manner taught in the grey and other like patents described above . a pair of side rails ( not shown ) may be affixed to the main frame 11 to extend upwardly along the sides of table 22 to prevent bales deposited thereon from making undesirable movements in a side direction . at the rearmost portion of the wagon 10 , there is positioned a stack forming region generally shown at 24 . the stack forming mechanism shown is also in the prior art and is comprised primarily of a table 26 which is pivotally mounted to the main frame 11 . tables 22 and 26 operate in the fashion known in the prior art . generally , in operation , bales are picked up by the loader 16 serially and deposited on edge in a line on bale - receiving area 14 . when the proper number of bales are in alignment , usually two , pusher 19 is activated to engage the bales and push them onto the forward portion of table 22 . this process is repeated until table 22 reaches its capacity . then , table 22 pivots to deposit the tier of bales on the load rack 24 where they are held substantially stationary . the entire process is repeated until the load rack contains a predetermined number of bales . load rack 24 may then be pivoted to deposit the stack on the ground behind the wagon . as further described in the above - incorporated co - pending patent application , various tie tier formations may be easily assembled by the structure shown . bales are deposited on edge , as depicted by bales &# 34 ; a &# 34 ; in fig2 on the bale - receiving area 14 , but must be rotated 90 ° before transfer to the second table and inclusion in a tie tier . the pusher mechanism 19 works in conjunction with bale - turning apparatus 18 to rotate the bales onto their flat sides . then , they may be either pushed directly onto the front portion of table 22 or pivoted 90 ° by the actuation of cylinders 30 and 31 , which causes swing arms 32 and 33 to engage the bales , and pushed onto table 22 in the rail bale positions designated &# 34 ; a &# 39 ;&# 34 ;. center bales are then positioned between rails bales a &# 39 ; by loading a single bale onto the bale - receiving area 14 and positioning it at location &# 34 ; b &# 34 ;. it too is then rotated 90 ° and pushed onto table 22 . this procedure is then repeated a sufficient number of times to completely load the table . the primary objective of the apparatus of the instant invention is to sense the presence of a bale at the two locations mentioned and to thereby activate the pusher cylinder 31 so that it will engage bales on the receiving surface 15 and transfer them to the second table 22 . more specifically , with reference to fig2 it is desirable to detect the presence of a bale at the position shown as &# 34 ; a &# 34 ;, which in fact means that there are two bales in line on the bale - receiving area . it is further desirable to detect the presence of a bale at the position shown at b in dotted line , which is the central location on the bale - receiving means . referring now more specifically to fig3 and 4 , the detail structure of the sensing means 40 of the instant invention will be described . a cantilevered somewhat inverted u - shaped contact arm 41 is secured for pivotable movement about a vertical axis to main frame 11 by a bearing 42 and a bracket 43 . the inboard end of arm 41 terminates in a substantially horizontal curved bale - engaging bar 44 . as can be seen more readily in fig2 the arm 41 extends rearwardly across the bale - receiving area of surface 15 , with the bale - engaging bar 44 positioned at a height to interfere with , or engage , bales on edge as they are moved across the bale - receiving area by conveyor 17 . an actuation member 46 , shaped somewhat like a vertical paddle , is affixed to arm 41 and moves through an arcuate path as the arm is rotated . actuation member 46 , and thus arm 41 , is biased toward the bale - receiving end of the bale - receiving area by a spring 47 . a sensor 48 , in the shape of an elongate arm , is rotatably affixed to the vertical portion of arm 41 . the outboard end of sensor 48 is affixed via rod 49 to control valve 51 , the function of which will be described below . sensor 48 includes a bolt 52 which is threadably engaged therewith to extend substantially horizontally toward actuation member 46 . the bolt 52 may be adjusted relative to sensor 48 to thereby modify the distance through which member 46 must travel for contact therewith . as can be seen , when arm 41 rotates in a counterclockwise direction , actuation member 46 moves therewith . when the member 46 contacts bolt 52 , it causes sensor 48 to also move in a counterclockwise direction , thus pulling rod 49 and actuating valve 51 . arm 51 terminates at the lower end thereof with a bracket 56 which rotatably supports an angular spacer support arm 57 about pin 58 . a spacer 59 , in the form of a bolt threadably engaged with the end of spacer support arm 57 , is thus movable from the position shown in fig3 upwardly into an interference between actuation member 46 and bolt 52 of sensor 48 . support arm 57 is biased downwardly at the spacer end by a spring 61 affixed to a brace 62 which is , in turn , fixed to main frame 11 . a pulley 63 directs a manual control cable 64 to the end of support arm 57 opposite spacer 59 . in operation , arm 41 is in the rest position shown as &# 34 ; r &# 34 ; in fig4 . the elements of the trip mechanism 40 are generally in the positions shown in fig3 and the operator is intending to sense the presence of two bales on the bale - receiving means . the first bale is picked up from the ground and deposited on the cross conveyor 17 for movement across bale - receiving area 15 . the bale engages bar 44 and moves the arm 41 to the first position shown as &# 34 ; f &# 34 ; in fig4 . a second bale is picked up from the ground and deposited on the cross conveyor 17 which moves the initial bale further across surface 15 until the arm 44 is in the second position shown as &# 34 ; s &# 34 ; in fig4 . at this time , the actuation member 46 engages bolt 52 and causes sensor 48 to rotate about its vertical axis of rotation and valve 51 to be actuated . by referring briefly to fig2 it can be seen that the high pressure input line 70 allows fluid to flow through valve 51 and onto selector control valve 71 . as taught in the above - identified incorporated co - pending patent application , selector valve 71 allows fluid to flow into cylinder 31 and thus cause pusher 19 to engage the bales and move them rearwardly onto the forward portion of the second table . if it is desired to sense the position of a single bale on the bale - receiving means , cable 64 is pulled , causing arm 57 to rotate about pin 58 and spacer 59 to move upwardly into position between actuation member 46 and bolt 52 of sensor 48 . a stop may be provided to insure proper interpositioning of the spacer . the bale is then deposited on the bale - receiving area in the normal fashion where it will first engage the arm 41 at position &# 34 ; r &# 34 ; of fig3 and move it to the first position &# 34 ; f &# 34 ; at which time the actuation member 46 engages spacer 59 which in turn engages bolt 52 and actuates valve 51 for operation of cylinder 31 . thus , it can be seen that the operator has a complete and simple control for determining when the pusher mechanism should be operated to transfer bales onto the tier - forming table for the formation of various tie or standard tiers . it will be understood that various other changes in the details , materials and arrangement of parts which have been herein described and illustrated in order to explain the nature of the invention will occur to and may be made by those skilled in the art , upon a reading of this disclosure , and such changes are intended to be included within the principles and scope of this invention . for example , the sensor 48 is shown as being mechanically connected to valve 51 ; however , one of skill in the art will readily understand that an electrical switch could be added to member 48 for electrical activation of the valve . also , one of skill in the art will appreciate that contact arm 41 need not necessarily rotate about a vertical axis , but rather could be l - shaped and rotate about a horizontal axis . such an arrangement would be operably equivalent to that shown , though perhaps not quite as structurally compact .
a bale wagon having a bale - receiving area , a bale - accumulating area , means for transferring bales from the bale - receiving area to the bale - accumulating area , and an improved means for sensing the location of bales on the bale - receiving area and activating the means for transferring is disclosed . the improved sensing and activating means includes a cantilevered arm pivotable about a vertical axis between first and second predetermined sensing locations . a follower fixed to the arm and movable therewith either activates a sensor after a predetermined amount of radial movement corresponding to the second sensing location , or engages a spacer which is caused to activate the sensor after another smaller amount of radial movement corresponding to the first sensing location .