Implement connecting coupling mechanism
United States Patent 11 1 1111 3,876,091 MacDonald 1 1 Apr. 8, 1975 IMPLEMENT CONNECTING COUPLING Primary Examiner-Leo Friaglia MECHANISM Attorney, Agent, or FirmPolster and Polster [75] Inventor: Raymore D. MacDonald, Eureka. Ill.  
  [57] ABSTRACT [73] Assignee: Rivinius, lnc., Woodford County.  
 m A coupler for connectmg a pr1me mover to an 1mplement has a coupling frame with side rails and top and Filed: J ly 6, 1974 bottom beams. Bearing sleeves, supported by the side rails. have latch pins journaled for reciprocation in [211 App! 492,044 them The latch pins have tapered outer ends. A prong, with a rounded top and an elongated shank. is 1 Cl 5; /273: 280/479 R mounted in the center of the top beam. and means are [51] Int. Cl E02f 3/70 vided for selectively adjusting the height of the 1 Field 0f 23O/479 479 rounded top surface of the prong with respect to the 0 axis of travel of the latch pins. An implement assembly mounted on the implement includes a frame with side [56] References Cited wings each having a socket with a bore tapered com- UNITED STATES PATENTS plementarily to and positioned to receive one of the 3.204.793 9/1965 Lane 214 145 x latchRinsr and a Feceptacle mounted frame in 3.285.625 11/1968 Krueger 2:;0 479 R a P0Smon IO recelve the Prong 0f the p g frame- 3.389.819 6/1968 Schumacher 214/145 X The receptacle has a central seat. concavely rounded 3.417.886 12/1968 Stuart 214/145 complementarily to seat the rounded top surface of 3.760.883 9/1973 Birk 214/145 the prong, and divergently sloping front and side walls. 3.794.195 2/1974 Clevenger et al. 214/145 4 Claims, 4 Drawing Figures PATENTED AFR 1975 SHEET 1 OF 2 FIG.|.  
 IMPLEMENT CONNECTING COUPLING MECHANISM BACKGROUND OF THE INVENTION Implement hitches of various sorts are old and well known. Examples of the patent art include U.S. Pat. to Sorenson, No. 2,888,995, Hess, No. 2,979,137, Todd, No. 3,195,65], and Stuart, No. 3,417,886. One of the common problems of coupling mechanisms known heretofore has been that, at least with heavy machinery couplings, if they are easy to connect and disconnect, they are likely to be sloppy, and if they are made tight, they are hard to assemble and disassemble.  
  One of the objects of this invention is to provide a coupling mechanism for heavy machinery such as front end loaders, which permits quick and easy connecting and disconnecting of attachments such as buckets, blades and plows, but at the same time mounts the implements firmly, securely, and without slop in the connection.  
  Other objects will become apparent to those skilled in the art in the light of the following description and accompanying drawings.  
 SUMMARY OF THE INVENTION In accordance with this invention, generally stated, a coupler is provided for connecting a prime mover to an implement, which has a coupling frame to be mounted on a part of the prime mover, the frame having side rails and top and bottom beams. Bearing sleeves, oriented substantially parallel to the beams, are supported by the side rails. Latch pins journaled for reciprocation in the bearing sleeves, have tapered outer ends directed outboardly of the side rails and are adapted to project beyond the side rails in one position of their reciprocal travel. A prong, mounted in the center of the top beam, has a rounded top surface and a shank, and means are provided for selectively adjusting the height of the rounded top surface with respect of the axis of travel of the latch pins. An implement assembly, mounted on the implement, includes an implement frame having side wings each carrying a socket with a bore tapered complementarily to and positioned to receive one of the latch pins, and a receptacle mounted on the implement frame positioned to receive the prong of the coupling frame. The receptacle has a central seat, shaped complementarily to seat the rounded top surface of the prong, and divergently sloping front and side walls. A  
 rear wall does not slope divergently with respect to the axis of the prong shaft, in the preferred embodiment.  
 BRIEF DESCRIPTION OF THE DRAWINGS In the drawing, FIG. 1 is a view in side elevation of one illustrative embodiment of coupler of this inven- DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings for one illustrative embodiment, of coupling of this invention, reference numeral 1 indicates a coupling frame, which&#39;is shown as mounted on arms 2 and 3 of a loader, not here shown.  
  The coupling frame 1 in this embodiment has side rails 4 and 5 in the form of heavy channels, defined by side walls 6 and 7 and an intermediate web 8, all welded together. The side rails 4 and 5 are connected top and bottom by a top beam 10 and a bottom beam 11 respectively.  
  Bearing sleeves 14 and 15 extend through and are welded to the side walls 6 and 7 around the periphery of aligned holes in the side walls 6 and 7 of the side rails 4 and 5 respectively. Also welded to the inside faces of the side walls 6 and 7 are bearing blocks 18 which serve to mount pins on which the ends of the arms 2 and 3 are mounted.  
  Slidably mounted in the bearing sleeves 14 and 15 are latch&#39;pins 20 and 21 respectively. The latch pins 20 and 21 are tapered at their outer ends 22 for the distance through which they project beyond the outer surface of the outer side walls 7 in their outwardly thrown position. In this embodiment, the latch pins 20 and 21 are hollow, and a compression spring 23 in-each one has its outer end seated against an annular shoulder 24 within the latch pin, and its inner end seated against a stop washer 25 retained by snap rings seated in grooves in the inner surface of the bearing sleeve. A retracting rod 27 threaded at one end into a threaded opening in the outer end of the latch pin is provided at its free end with part of a clevis fitting by which the latch pin can be retracted from the outwardly extended position to which it is biased normally by the compression spring 23. Complementary clevis fittings on pull rods 28 connect the retracting rods 27 to a lever 30 at points equispaced from and on opposite sides of the axis of a pivot 31, on which the lever 30 is mounted between a pair of stanchions 32 extending between the top and bottom beams 10 and 11. In the embodiment shown, the lever 30 is shown as provided with a dog-leg handle 31, offset to clear the top beam 10, by which the latch pins can be moved manually. A tab 33 projects far enough beyond the beam 10 to catch the handle 31 to hold it in its pin-retracting position, but not enough to prevent the handles being warped around it manually to clear the tab and release the latch pins to permit them to be moved, by the bias of the springs 23, into latching position. Also shown in dotted lines is a connecting rod 32 which may be connected to a hydraulic or pneumatic cylinder device if desired.  
  Mounted in the center as viewed in FIG. 2, of the top beam 10, is a heavy, internally threaded collar 40, in which an externally threaded shank 42 of a prong 45 is mounted. The prong 45 has a hemispherical top 46. The construction of the shank and collar, and of the beam 10 are such that the shank can be screwed down or up through a substantial distance, such, for example, as an inch.  
  Referring now to FIGS. 1, 3, and 4, an implement 50., in this example, a bucket, is shown as provided with an assembly 52 consisting of an implement frame 53 which includes heavy side wings 54 and 55, carrying sockets 56 and 57. and a receptacle 60, which is mounted in the center, widthwise as viewed in FIGS. 3 and 4, of the implement frame.  
  The sockets 56 and 57 have bores 58 tapered complementarily to the taper of the latch pins 20 and 21.  
  The receptacle 60 includes a central seat 63 shaped concavely complementarily to the top 46 of the prong 45. The receptacle 60 includes side walls 65, front wall 66, and rear wall 67. As shown in FIG. 3. the side walls 65 diverge outwardly from the seat 63. and the front wall 66 extends at an outwardly divergent angle from a radial line from the center of the seat. The rear wall 67 is. in this embodiment, parallel to the radial line from the center of the seat 63 which is also the axis of the prong when the prong is seated in the seat 63 and the latch pins 20 and 21 are seated in the sockets 56 and 57.  
  The outward divergence of the walls 65 and 66 makes the insertion of the prong 45 into the receptacle 60 easy. while the non-divergence of the rear wall 67 ensures that the prong is not easily dislodged accidently while the connection between the frames is being made.  
  The side wings 54 and 55 embrace the side rails 4 and 5, and stabilize the implement. The tapered ends 22 of the latch pins 20 and 21 engage the wall defining the bores 58 tightly. to prevent any play. being biased into continuous. self-tightening engagement by the springs 23.  
  Because the effective distance between the common axis of the latch pins and the rounded top of the prong is infinitely variable through the range of distance through which the shaft of the prong can be moved axially. it is possible easily to obtain a tight fit. and to maintain that tight fit. between the two parts of the coupling of this invention.  
  It can be seen that other methods of adjustment. besides a screw thread. can be used. For example. a set screw in the collar can bear against the shank which can be smooth. or the collar itself can be made in the form of a clamp. Shims can be used. either alone or in conjunction with any of the other forms. to provide a positive reference base. These are merely illustrative. The taper on the latch pins is doubly advantageous. not only in locking the elements together tightly. but in permitting an easy entrance of the small end of the latch pin into the widest portion of the bore. The hemispheric surface of the prong permits self centering of the implement. when the prong is inserted and the coupling frame raised. by means of the arms 2 and 3 of the loader.  
  In operation. to couple the loader to an implement resting on the ground as indicated in FIG. 1. the lever 30 is initially thrown to the position at which the latch pins 20 and 21 are moved inboard. against the bias of the spring 23. until the outer ends of the pins are flush with the outer surface of the side wall 7 and held in that position by the tab 33. It is only necessary to lower the arms 2 and 3 of the loader until hemispherical top 46 is below the lower edge of the wall 67 of the receptacle 60. the loader is moved toward the implement until the hemispherical top has cleared the wall 67 inboard of the wall. and the coupling frame is raised. by means of the arms 2 and 3. until the hemispherical top seats in the seat 63. Continued raising of the coupling frame will lift the implement. causing it to rock toward the position at which the implement frame is flat against the coupling frame. and the latch pins are aligned sufficiently with the bores 58 of the implement sockets to permit their entry when the lever 30 is thrown to the position shown in FIG. 2. In demounting the implement. the implement is brought to rest on the ground. the latch pins are retracted. the prong dropped below the wall 67, and the loader backed away.  
  Numerous other variations in the construction of the coupler of this invention. within the scope of the appended claims. will occur to those skilled in the art in light of the foregoing disclosure.  
  Having thus described the invention. what is claimed and desired to be secured by Letters Patent is:  
  l. A coupler for connecting a prime mover to an implement. comprising a coupling frame adapted to be mounted on a part of said prime mover. said frame having side rails and top and bottom beams: bearing sleeves. oriented substantially parallel to said beams. supported by said side rails; latch pins journaled for reciprocation in said bearing sleeves. said latch pins having tapered outer ends directed outboardly of the side rails and adapted to project beyond said side rails in one position of their reciprocal travel; a prong mounted in the center of said top beam. said prong having a rounded top surface and a shank. and means for selectively adjusting the height of said rounded top surface of the prong with respect to axis of travel of the latch pins: and an implement assembly mounted on said implement and including an implement frame having side wings each carrying a socket with a bore tapered complementarily to and positioned to receive one of the latch pins of the coupling frame. and a receptacle mounted on said implement frame in a position to receive the prong of the coupling frame. said receptacle having a central seat. shaped complementarily to seat said rounded top surface of the prong. and divergently sloping front-and side walls.  
  2. The assembly of claim I wherein a rear wall of the receptacle makes a lesser angle with respect to the axis of the prong shaft than the other walls of the receptacle.  
  3. The coupler of claim 1 wherein the prong has a hemispherical head and an elongated shank of lesser diameter than the head.  
  4. The coupler of claim 1 wherein the shank of the prong is cylindrical and is threaded externally. and is received into an internally threaded collar secured to the top beam.