Self aligning trailer hitch

A self aligning trailer hitch, used by a driver alone without creating any personal lifting force, to couple and decouple a towing vehicle and a trailer, has a multiple piece assembly of a socket for securement to a towing vehicle, having a rotatable claw, which has a spherical recessed surface adapted to receive a portion of a lower ball of a vertical dual ball assembly, which is secured to a towed vehicle. Upon hitching the vehicles together, the rotatable claw contacts the lower ball, when this socket is moving horizontally, during movement of a towing vehicle toward the towed vehicle, causing the lower ball to be repositioned upwardly and over center, while being guided in a vertical plane, and then held in the radially upwardly repositioned spherical recessed surface of the rotatable claw. A three dimensional ramp guides the lower ball to fully contact the spherical recessed surface of the rotatable claw. This ramp has an entry ramp portion, respective left and right side portions, which commence widely spaced to create a wide mouth entrance, and thereafter converge to a narrow throat exit, and also respective left and right integral curved transition portions, located between the entry ramp portion and the respective side portions, having a radii of these curved transition portions. Another spherical recessed surface, located on the multiple piece socket assembly, receives a portion of a lower ball stopping it, and contributing to the holding thereof. A lock keeps the rotatable claw in this lower ball holding position. This self aligning trailer hitch may include a load equalizer assembly.

BACKGROUND 
Most of the trailer hitches used today still have an upstanding ball on the 
towing bar of the towing vehicle and the inverted socket mounted on the 
tongue of the trailer. The alignment of the inverted socket over the 
upstanding ball and the subsequent vertical motion engagement of the 
inverted socket down over the upstanding ball is still today often a time 
consuming process and often a risk assuming process. This is especially so 
when the driver of the towing vehicle must couple or hitch the towing 
vehicle to the trailer without the assistance of another person. Moreover, 
when the trailer tongue weight is high, and/or the trailer is heavy, a 
person has difficulty making any adjustments in pre-positioning the 
inverted socket over the upstanding ball. 
There have been and are trailer hitches and accessories therefore, which 
are directed to making it more convenient and/or safer to couple or to 
hitch a towing vehicle to a trailer. Cyril L. Carter in 1970 in his U.S. 
Pat. No. 3,521,908 illustrated and described his self aligning trailer 
hitch, which during the coupling has an extending and pivotal hitch bar 
portion to undertake the alignment in a convenient way. Then following the 
initial coupling, the pivotal hitch bar portion, upon relative motion of 
the vehicles, is telescoped within the encompassing tow bar, and then 
locked into place during the towing time of the coupled or hitched towing 
vehicle and the trailer. 
Daniel C. Miller in his U.S. Pat. No. 3,879,062 in 1975, disclosed his 
trailer hitch guide, used in directly guiding the leading end of a trailer 
tongue, so the inverted socket thereon, would be in vertical alignment 
over the mating hitch ball on the tow bar of a towing vehicle. His trailer 
hitch guide had a V shaped element supported by other portions thereof, in 
turn supported on portions of the towing vehicle. 
Woodrow F. Thompson in his two patents, U.S. Pat. No. 3,588,145 of 1971 
pertaining to a trailer hitch, and U.S. Pat. No. 3,801,133 of 1974 
pertaining to a load leveling and anti-sway trailer hitch, illustrated and 
described the use of his shovel or guide plate. Whether or not the ball 
was on the towing vehicle or the trailer, or the socket was on the vehicle 
or the trailer, his guide plate was positioned to direct the relative 
motion approach of the ball and socket, so they would be in vertical 
alignment. Then subsequent vertical lowering of the trailer tongue would 
bring the ball into engagement within the socket. 
Also Mr. Thompson in his U.S. Pat. No. 3,801,133 illustrated and described 
how his load leveling bars were arranged for pivotal movement about an 
axis, which was coincident with the vertical axis of the ball and socket 
coupling. 
Arthur John Hameri in his U.S. Pat. No. 3,679,243 of 1972 discloses his 
coupling assembly wherein a depending ball secured to a trailer tongue 
rides up a ramp and drops down in a holding cavity. A cover plate is 
secured thereafter to keep the ball in the holding cavity. 
Also Arthur John Hameri in his British patent 2,175,262 A of 1986 
illustrated and described a ball and socket coupling wherein a depending 
ball rides up a ramp and drops down into a two piece cavity, one piece of 
which is moved to lock and unlock the depending ball in the cavity. 
These persons and other people have provided trailer hitches which have 
helped the owners and operators of towing vehicles to couple the ball and 
socket of respective trailers with greater convenience, safety and speed. 
Yet there remained a need for providing a trailer hitch which could be 
readily adapted for coupling securement to a towing vehicle, in a well 
understood way, to provide a combined self alignment structure with a 
better receiving socket structure, to guide, receive, align, and encompass 
a ball, conveniently and quickly secured to a conventional socket equipped 
trailer tongue of a trailer. Moreover, the decoupling would also be 
conveniently and safely undertaken. 
SUMMARY 
This self aligning trailer hitch with or without its load equalizing 
subassembly is used safely, quickly, and conveniently by persons in a wide 
age range, who, as necessary, may be required to couple their towing 
vehicle to a trailer, without the assistance of another person. No longer 
must the socket and the ball be first vertically aligned for subsequent 
vertical relative movement to complete the coupling, as the ball is 
vertically moved axially into the socket. No longer must load equalizing 
bars at their respective ends be forcefully raised to create the bending 
moments used in leveling the towing vehicle and the trailer. 
Now a vertical arrangement of dual balls is secured to a trailer tongue, as 
the top ball is secured to the inverted socket on the tongue, to 
thereafter present a depending bottom ball on the trailer tongue. Then 
secured to a tow bar, in turn secured to the frame of a towing vehicle, is 
a self aligning multiple piece assembly of a socket positioned on a hitch 
head body. When relative motion occurs between the depending bottom ball 
and this socket assembly, which occurs as the towing vehicle is backed up 
to the trailer, the depending bottom ball after being contacted by a three 
dimensional non bindable guiding ramp or chute of the socket assembly is 
guided centrally and upwardly to be ultimately positioned, in part, 
against a ball receiving complementary hold down seat of the socket 
assembly. During this centrally and upwardly travel the depending bottom 
ball bears against an initially downwardly rotated ball receiving claw of 
the socket assembly, and soon causes the upward rotation of the ball 
receiving claw. When the ball reaches the hold down seat, the receiving 
claw has moved into a socket creating position to hold the ball in place 
completing the load carrying coupling or hitching of the towing vehicle 
and the trailer. This socket creating position is insuredly maintained by 
the upward installation of a locking abutment, which interfits with the 
receiving claw to keep it from rotating. Moreover a locking pin is used to 
keep the locking abutment in place, to complete the closure of the 
multiple piece socket assembly about the depending bottom ball, where it 
so remains during the pulling of the trailer. 
At this time the towing vehicle and the trailer are joined for towing, 
unless load equalizing is needed. If so, then in reference to one 
embodiment of a load equalizer assembly, the locking abutment used also 
has a depending pivoting link subassembly. It is used to secure the 
forward closed end of a wishbone, using a chain link, equalizing bar 
subassembly, which is adjustably secured to the tongue of a trailer. By 
using the trailer tongue jack, the coupling is raised and then the 
wishbone equalizing bar subassembly is easily secured. Thereafter upon 
lowering the coupling by using the jack, the wishbone is tensioned and the 
load equalization is completed. 
Also if a load equalizer assembly is needed in another embodiment, the 
locking abutment is an upstanding lug portion of a lock lug, which is 
formed with a depending shaft which receives an equalizing arm. This arm 
in turn is secured to the tongue of a towed vehicle by a compression 
spring assembly.

DESCRIPTION OF PREFERRED EMBODIMENTS 
A preferred embodiment of the self aligning trailer hitch 20 and the 
optionally used load equalizer 22 are illustrated in FIGS. 1 through 17 in 
the drawings. In FIGS. 1 and 2, they are shown as viewed respectively from 
the top and from the side, and as connected to a towing vehicle 24 and to 
a trailer 26, as further shown in FIGS. 15 and 16. 
Other preferred embodiments, centering on another embodiment of a load 
equalizer 290 are illustrated in FIGS. 18 through 45. 
Rotatable Claw and Vertical Pair of Balls 
The self aligning trailer hitch 20 centers about the operation of a 
rotatable claw 28, which contacts a lower ball 30 of a vertically arranged 
pair of balls 32, which also includes the upper ball 34. After the 
essentially horizontal motion contact is made, the rotatable claw 28 
rotates in a vertical plane about a horizontal axis, as shown in FIGS. 11, 
12 and 13, to directly capture the lower ball 30 using the spherically 
shaped partial recess 36, also referred to as the capturing socket 36. The 
lower ball 30 during its capture does not drop down into a cavity. Instead 
the lower ball is moving essentially horizontally, encountering only a 
slight up and over center motion, as shown in FIGS. 11, 12, and 13. 
When this rotatable claw 28 rotates during this coupling motion, it is 
transporting and repositioning the lower ball 30, which follows a radially 
upwardly movement path. 
Later after the towing is completed, and decoupling is undertaken, the 
reverse rotation of the rotatable claw 28, to again reposition the lower 
ball 30, is undertaken without creating any hindering resisting frictional 
forces, as the lower ball 30 freely follows a radially downwardly movement 
path to arrive at the ball guiding ramp 38. 
Ball Guiding Ramp 
To insure this rotatable claw 28, as soon as possible, will be contacting 
the lower ball 30, the self aligning trailer hitch 20 has a three 
dimensional, non bindable, ball guiding ramp 38 to contact the lower ball 
30, at the start of the coupling function, to guide the lower ball 30, as 
may be necessary, by redirecting the motion thereof either upwardly and/or 
sideways, as shown in FIGS. 11, 12, 13 and 14. This ball guiding ramp 38 
has an entry ramp portion 40 and respective left and right side portions 
42, 44, which commence at a wide mouth entrance 46 and thereafter converge 
to a narrow throat exit 48. There are integral curved transition portions 
45 located between the entry ramp portion 40 and the respective left and 
right side portions 42, 44, having a radii that keeps the lower ball from 
being jammed on this ramp, to essentially, in effect, insure the lower 
ball 30 will only be contacting the non bindable guiding ramp 38 at one 
contact point at one time. 
As particularly viewed in FIG. 4, and also shown in FIGS. 1, 3, and 6, as 
the lower ball 30 is being guided by the ball guiding ramp 38 to meet the 
rotatable claw 28, in reference to the spherical size of this lower ball 
30, and to the greater spacing size of the ball guiding ramp 38, inclusive 
of the large enough radii of the transition portions 45, the lower ball 30 
is only contacting at any one time only one of the following: the entry 
ramp portion 40 of the ball guiding ramp 38, left side portion 42 thereof, 
right side portion 44 thereof, or one of the integral curved transition 
portions 45 thereof. These respective sizes insure there will be no 
binding of the lower ball 30 in the three dimensional, non bindable, ball 
guiding ramp 38. 
In recent years, the manufacturers' clearance has been reduced between 
where a trailer ball is coupled and the apex end of the trailer tongue 
and/or the frame members of a trailer. Therefore, there is a more limited 
space to accommodate the operational clear positioning of components such 
as this ball guiding ramp 38, when the towing vehicle and the towed 
vehicle are coupled up and underway. 
Convenient Connection of Components of the Self Alignment Trailer Hitch to 
the Tongue of a Trailer 
The pair of balls 32, are integrally and vertically arranged with a mid 
cylindrical portion 50, presenting a flange like appearance, between the 
lower ball 30 and the upper ball 34. As shown in FIGS. 7 and 8, the upper 
ball 34 is inserted up and into the inverted socket 52, which is 
essentially permanently secured to the tongue 54 of the trailer 26, via 
the socket assembly 56, which also includes the latch 58 used to keep the 
upper ball 34 confined in the socket 52, and connected to the trailer 26. 
Convenient Connection of Components of Self Alignment Trailer Hitch to the 
Tow Bar of a Towing Vehicle 
There are several parts which are similar to those parts currently used in 
other trailer hitches. As shown in FIGS. 1, 2, and 3, an extending tube 60 
of a tow bar assembly 62, or draft bar assembly 62, is secured to a towing 
vehicle 24, by welding and/or bolting to vehicle frame members, not shown. 
A tow bar 64 has a horizontal leg 66, which telescopes into the extending 
tube 60 and is secured by using a loop headed shear pin 68, in turn 
retained by a cotter like safety pin 70. The tow bar 64 also has a 
vertical leg 72 creating an overall T shaped tow bar 64. A group of 
vertically spaced transverse holes 74 are provided in this vertical leg 
72. A triangular reinforcing plate 76 is secured to be an integral part of 
the T shaped tow bar 64. This arrangement of the tow bar assembly 62, 
having the extending tube 60 and the T shaped tow bar 64 is like or very 
similar to like parts of other trailer hitches now in use. 
Then as to the different parts which continue the convenience of the 
connection of this self aligning trailer hitch 20, a hitch head body 80 is 
provided to be bolted in place at a selected vertical height on the 
vertical leg 72 of the tow bar 64. Threaded bolts 82 are passed through 
the holes 84 of the channel receiving portion 86 of the hitch head body 80 
and the selected holes 74 of the vertical leg 72, and thereafter these 
bolts 82 are secured by nuts 85. 
This hitch head body 80 serves to position all the different components of 
the multiple piece socket assembly 88, as shown in FIGS. 1, 2, 3, 4, 5, 
and 6. There is a central receiving cylindrical like volume 90, having a 
vertical centerline 91, to receive the lower ball 30 above and to receive 
the rotatable claw 28 below in the lower ball receiving position. Upon the 
hitching of the towing vehicle 24 and the trailer 26 and change of 
position of the rotatable claw 28, the upper portion of this volume 90 
takes on a spherical volume appearance to receive and to hold the lower 
ball 30. The rotatable claw 28 is rotatably secured by using a transverse 
shaft 92, passed through the holes 94, 96, which is retained, via the 
shaft head 98 and the hair pin shaped keeper 100, which is inserted in the 
radial hole 102. 
This hitch head body 80 is integrally formed to include the ball guiding 
non bindable ramp 38, having the entry portion 40, the left and right side 
portions 42, 44, arranged to have a wide mouth entrance 46 and a narrow 
throat exit 48. As previously described, oftentimes today there is less 
clearance available between where a trailer ball is coupled and where the 
apex of the trailer tongue is located, and consequently often less 
clearance in reference to trailer frame members. Therefore to decrease the 
longitudinal length needed of the ball guiding ramp 38, the entry portion 
40 is integrally formed to include a recess 104, through which rotatable 
claw portions 106 pass during the upward rotation of the claw 28. 
An integral central gusset 108 of the ball guiding ramp 38, bisects the 
recess 104, creating the spaced side by side openings 110, 112, which then 
comprise the recess 104. The rotatable claw 28 has complementary spaced 
side by side claw portions 113, 114, which rotatably pass through the 
spaced side by side openings 110, 112. The integral central gusset 108 
protectively guides the upward motion of the lower ball 34 during the 
coupling of the towing vehicle 24 and the trailer 26. Such protective 
guiding, via the integral gusset 108, avoids any possibility of an initial 
or follow on jamming of the lower ball 30 upon its entry into its 
trailering position when guided by this shortened ball guiding ramp 38. 
The hitch head body 80 integrally provides a spherical recessed surface 
116, at the top 118 of the central receiving cylindrical like volume 90, 
also referred to as the central receiving volume 90, to receive a 
sufficient portion of the lower ball 30 to stop the entering motion 
thereof. This spherical recessed surface 116 is another portion of the 
multiple piece socket assembly 88, which eventually presents a spherical 
appearing volume at this top 118. 
Also the hitch head body 80 integrally provides a vertical planar receiving 
and abutment surface 120 at the bottom 122 of the central receiving 
cylindrical like volume 90, also referred to as the central receiving 
volume 90. This vertical planar receiving and abutment surface 120, along 
with a right angled locking notch 124, in the rotatable claw 28, define a 
lock receiving volume 126, when the rotatable claw 28 is rotated upwardly 
and the lower ball 30 is in the capturing socket 36. 
A locking insert member, is designated as a locking lug 128, and the 
upwardly directed placement of this locking lug 128 in the lock receiving 
volume 126, secures the rotatable claw 28 in place, when the lower ball 30 
is in the capturing socket 36. This locking insert member 128 is an 
upstanding portion 128 of a pivoting link assembly 130. The locking insert 
member 128 is kept in its upward position by using a transversely placed 
quick pin 132 passed transversely through horizontally spaced holes 134, 
136 in the hitch head body 80. 
The hitch head body 80 with the integral spherical recessed surface 116, 
and the capturing socket 36, also referred to as the spherical partial 
recess 36 of the rotatable claw 28, together become the multiple piece 
socket assembly 88, to receive the lower ball 30. 
The Horizontally Directed Coupling of the Lower Ball Secured to the Trailer 
Tongue to the Multiple Piece Socket Assembly Secured to the Tow Bar 
Assembly of the Towing Vehicle 
As shown in FIGS. 7 through 10, the pair of balls 32, via the upper ball 34 
are inserted in the inverted socket 52 on the tongue of trailer 54, and 
secured by the latch 58, as shown in FIGS. 7 and 8. Or alternatively, a 
heavy duty embodiment 140 of a pair of balls 30, 34, are inserted in the 
inverted socket 52 on the tongue of a trailer 54, and secured both by the 
latch 58, and also by using the strong, clip like retainer 142, as shown 
in FIGS. 9 and 10. 
Then with rotatable claw 28 rotated fully downwardly, as freely occurs via 
the weight distribution of this rotatable claw 28, the spherical partial 
recess 36, also referred to as the capturing socket 36 is positioned to 
horizontally receive the lower ball 30, as shown in FIG. 11. 
The motion arrows indicate, throughout FIGS. 11, 12, and 13, the 
approaching of the rotatable claw 28 of the tow bar assembly 62, on the 
towing vehicle 24, being backed toward the lower ball 30 of the pair of 
balls 32 held in the inverted socket 52, via the upper ball 34 and latch 
58, on the tongue 54 of the trailer 26. In FIG. 12, the lower ball 30 is 
shown making the essentially initial contact with the capturing socket 36 
of the rotatable claw 28. Then in FIG. 13, the lower ball 30, while still 
remaining in contact with the capturing socket 36, has contacted the 
integral spherical recessed surface 116 of the hitch head body 80 located 
at the top 118 of the central receiving volume 90 of the hitch head body 
80. At this full longitudinal motion hitching time, the finger portions or 
claws 144, 146, of the rotatable claw 28, have blocked the return 
horizontal exit of the lower ball 30. Also they have blocked the upper 
vertical raising of the lower ball 30, in cooperation with the spherical 
recessed surface 116, integrally formed in the hitch head body 80. Then 
the capturing socket 36 also has blocked the lower vertical dropping of 
the lower ball 30. Moreover, the spherical recessed surface 116 continues 
to block the horizontal advance of the lower ball 30. Therefore this 
multiple piece socket assembly 88, as shown in FIG. 13, securely positions 
the lower ball 30 in respect to all possible directions of possible 
movement. 
To insure there will be no counter rotation of the only moving part of this 
multiple piece socket assembly 88, the movable rotatable claw 28, via its 
slightly tapered near right angled locking notch 124, is locked into 
position by the like slightly tapered locking insert 128, or locking lug 
128. The locking insert 128 is held in the locking position by the quick 
pin 132, as shown in FIG. 13. 
During the horizontal motion of the coupling, any reasonable misalignment 
is corrected as the lower ball 30 is guided by the ball guiding ramp 38, 
in a non binding way, as shown in FIG. 14. The entry portion 40, and the 
left and right side portions 42, 44 cooperatively guide the lower ball 30 
to the capturing socket 36 of the rotatable claw 28. Below the entry 
portion 40 in a horizontal portion presenting a rub surface 219. 
When the Equalization of the Loads is Undertaken to Result in the 
Substantial Leveling of Both the Towing Vehicle and the Trailer, Then a 
Load Equalizing Assembly is Used Having a Wishbone Equalizing Bar Sub 
Assembly. 
As illustrated in FIGS. 15 and 16 load equalizing or load equalization 22 
is undertaken, when a load equalizing assembly 150 is installed. As shown 
in FIGS. 3, 6, and 13, when the load equalizing assembly 150 is to be 
installed, then the pivoting link assembly 130, having the locking insert 
128, which also serves as a locking lug in part, is utilized, in lieu of 
just the locking lug 128. It is retained in position by the quick pin 132, 
and serves to keep the rotatable claw 28 in its lower ball 30 retaining 
position, as shown in FIG. 13. 
The pivoting link assembly 130, has a link body portion 152 integrally 
supporting the locking insert 128 and integrally presenting spaced top and 
bottom aligned hinge or bearing portions 154, 156, presenting vertically 
aligned holes 158, which are on the vertical center line 91 of the central 
receiving volume 90 of the hitch head body 80. Then when the lower ball 30 
is in its captured position, the vertical center line 91 also passes 
through the center of the lower ball 30. This center line 91 is offset 
from the parallel center line 159 passing through the shaft 92 for the 
rotatable claw 28, by five sixteenths of an inch in an embodiment. Thereby 
the lower ball 30 is in an over center position during the towing 
operational times. 
With the lower ball 30 on this vertical center line 91 along with pivot 
location of the pivoting link assembly 130, the rotation of the trailer 
tongue 54 and the rotation of the load equalizing assembly 150 are 
desirably both positioned to rotate about this vertical center line 91. 
Also the over center position of the lower ball 30 on vertical center line 
91 ahead of the shaft 92 of the rotatable claw 28 on the parallel vertical 
center line 159, is very useful during the hitching operation. When the 
towing vehicle has an automatic transmission and the driver completes the 
first coupling step, while the transmission is in the drive position, then 
when he or she places the transmission in the park position, the vehicle 
tends generally to move slightly. However, this slight movement does not 
successfully tend to decouple the lower ball 30, as it might otherwise, 
because this over center first coupling of the lower ball 30, following 
the vertical rotation of the rotatable claw 28, serves to keep the lower 
ball 30 retained in place, during the automatic transmission's 
characteristic caused movement of the vehicle, when shifting occurs from 
the reverse position to the park position. This non movement of the lower 
ball 30 is maintained, even though the driver has now left his or her 
driver's seat to come back to this self aligning trailer hitch to complete 
his or her physical upwardly insertion of the locking insert 128, and the 
following horizontal insertion of the quick pin 132. 
It is to be noted, that when the locking insert 128 is part of the entire 
hook up of the load equalizing assembly 150, which it is, when such an 
assembly 150 is to be installed, then this locking insert 128 must be 
raised up and inserted and the quick pin 132 must be inserted by the 
driver to complete both the entire coupling and the securement of the 
equalization assembly. This procedure required of the driver insures that 
the lower ball 30 will be carrying the main coupling load, and the load 
equalizing assembly 150 will not be carrying the main coupling load. In 
reference to other trailer hitches, their load equalizing assemblies have 
unexpectedly carried the main coupling load, causing an unwanted very 
dangerous unsatisfactory towing coupling condition which may fail when 
towing is underway. 
The pivoting link assembly 130, also includes a horizontal connector bar 
160 having at one end integral spaced top and bottom aligned hinge or 
bearing portions 162, 164, presenting vertically aligned holes 158, which, 
when complementary fitted between and with the spaced top and bottom 
aligned hinge or bearing portions 154, 156 of the link body portion 152, 
are also on the vertical center line 91. They are then rotatably joined by 
using the vertically positioned headed shaft 166, which passes through all 
the alike vertically aligned holes 158. 
At the other end of the horizontal connector bar 160, there are integral 
side by side spaced bearing portions 168, 170 presenting horizontally 
aligned holes 172. The spacing permits the controlled entry of portions of 
a chain link 174, which is then held in place by another transverse quick 
pin 176. The top surface of the connector bar 160 rubs against the rub 
surface 219, eliminating high stress at pin 166 in parts 128 and 160, and 
creating anti-sway resisting forces during towing. 
The chain link 174, before its retention by the quick pin 176, has been 
placed over an end 178 of a wishbone equalizing bar 180 of a V shape, and 
moved to the apex 182 of the V. Therefore the connection of the chain link 
174 to the connector bar 160 of the pivoting link assembly 130, also 
connects the V shaped wishbone equalizing bar 180 to the tow bar assembly 
62 of the towing vehicle 24. 
The respective widely spaced threaded ends 178, 184 of the V shaped 
wishbone equalizing bar 180 are preferably each connected to turnbuckle 
assemblies 186, which are secured respectively to left and right anchor 
clips 188, 190, using threaded bar sections 191 passing through selected 
holes 192, in respective groups of spaced holes 192, in respective 
projecting flanges 194, 196 of the angle anchor clips 188, 190, and then 
are secured by bolts 197. The other flanges 198, 200 of the angle anchor 
clips 188, 190, have spaced holes 202, which receive the threaded ends 204 
of U-bolts 206. These U-bolts are respectively passed about the left and 
right channels 208, 210, of the trailer tongue 54, and then their threaded 
ends 204 are respectively passed through the spaced holes 202 in the other 
flanges 198, 200. Thereafter they are secured by the nuts 212 threaded on 
the threaded ends 204 and tightened. 
When a towing vehicle 24 and a trailer are first equipped with all the 
components of this self aligning trailer hitch 20, only then is the 
securement undertaken of this V shaped wishbone 180, with the chain link 
174 in place. The anchor clips 188, 190 once secured to the trailer tongue 
54 by the U-bolts 206 and nuts 212, so remain secured for subsequent 
travels. The threaded ends 178, 184 of the V shaped wishbone 180 remain 
secured to the anchor clips 188, 190, via the turnbuckle assemblies 186, 
the threaded bar sections 191 and the nuts 197. Only must the chain link 
174 be connected to the horizontal connection bar 160, each time the 
trailer 26 is to be load equalized with respect to the towing vehicle 24, 
as the final step is undertaken by using the quick pin 176. 
As shown in FIGS. 15 and 16, after the lower ball 30 has been captured in 
the multiple piece socket assembly 88 upon the rotation of the rotatable 
claw 28 and the locking thereof, the trailer jack 216, upon turning of the 
crank handle 218, is used to raise the tongue 54 of the trailer 26. While 
remaining in this raised position, the chain link 174 is positioned with 
respect to the horizontal connection bar 160 and connected thereto via the 
quick pin 176 passing through the holes 172 of the spaced hinge or bearing 
portions 162, 164 and the chain link 174. 
Then while and after the trailer jack is lowered, the load equalizing 
assembly 150 becomes effective in leveling both the towing vehicle 24 and 
the trailer 26. Only during the initial hook up of a paired towing vehicle 
24 and a trailer 26 will all the other fastening steps be required. In 
general, then when a particular towing vehicle 24 and a particular trailer 
26, during an overall trip are intentionally separated at a stopover 
locale, in respect only to the load equalizing assembly 150, the only 
disconnect will be the clearing of the chain link 174 by the withdrawal of 
the quick pin 176. 
Also to be remembered, the locking insert 128 portion of link body portion 
152 of the pivoting link assembly 130 must be cleared, after first 
removing the quick pin 132. Then the rotatable claw 28 is free to 
reversely rotate, as the towing vehicle 24 is pulled forward clear of the 
trailer 26. Also the safety chains, not shown, must be cleared. Moreover, 
the electrical connections (not shown) for the lighting of the trailer 26, 
must be disconnected. 
Independent of the time periods required for these chain connections and 
electrical connections, this self aligning trailer hitch 20 is very 
quickly aligned and coupled for a trip. If load equalization 22 is 
undertaken, the load equalizing assembly 150, previously, essentially, and 
substantially, arranged and connected during the first pairing of a towing 
vehicle 24 and a trailer 26, is quickly finally secured, via using the 
chain link 174 with the pivoting link assembly 130. Also during the 
coupling the ball guiding ramp 38 quickly redirects, aligns, and directs 
the horizontal motion entry of the lower ball 30 into captive retainment, 
via the motion of the rotatable claw 28, within the multiple piece socket 
assembly 88, to quickly complete a very secure coupling of this self 
aligning trailer hitch 20. The towing vehicle 24 and the trailer 26 
remained coupled, and if a load equalizing assembly 150 has also been 
quickly interconnected, then the towing vehicle 24 and the trailer 26 
remain essentially level on level roadways. The uncoupling is likewise 
quickly undertaken. 
The equalizing assembly 150 is arranged with the V shaped wishbone 180 
being in tension, and not under bending stresses. The pivoting of the 
equalizing assembly 150 is about the centerline 91, which also passes 
through the center of the lower ball 30 and the upper ball 34, when the 
coupling is complete. Therefore there are no off center torque arms 
present to create any unwanted reactive forces. 
When the towing vehicle 24 and the trailer 26 are so coupled, with this 
self aligning trailer hitch 20, the resulting driving, handling and riding 
of the overall coupled vehicles are very satisfactory in respect to all 
roadway surfaces and contours. 
The Load Equalizing Assembly Is Useful With Other Trailer Hitches 
In FIG. 17, the load equalizing assembly 150 is shown in greater detail for 
two purposes. One purpose is to illustrate how this assembly 150 may be 
used with a prior art trailer hitch. The other purpose is to illustrate, 
in reference to FIGS. 15 and 16, how this load equalizing assembly 150 is 
secured to the pivoting link assembly 130 as shown in FIGS. 15 and 16. 
Another Load Equalizing Assembly of Another Overall Self Aligning Trailer 
Hitch 
In respect to other embodiments of components used in conjunction with the 
basic configuration of the double balls 32, the vertical rotatable claw 
28, and the ball guiding ramp 38, another preferred load equalizing 
assembly 290 is illustrated in FIGS. 18, 19, 20, and 21 assembled or about 
to be assembled with other components of an overall self aligning trailer 
hitch 295. In FIGS. 22 through 45 various different components in their 
different embodiments are illustrated. 
In FIG. 21 the components of this overall self aligning trailer hitch 295 
are illustrated spaced apart, before their assembly, as shown in FIG. 18. 
The components assembled and secured to the towing vehicle are the same as 
shown in FIGS. 1, 2, and 3, with respect to the first embodiment. They 
are, for example, the ramp 38, the rotatable claw 28, the hitch head body 
80, the quick pin 132, and the tow bar assembly 62, having the extending 
tube 60 and the vertical leg 72. 
In respect to the vehicle to be towed, there is the trailer tongue 54 
having a receiving socket assembly 52, such as the "Atwood" assembly 52, 
and the trailer jack 216, just as shown previously in FIGS. 1, 2, and 3. 
However, the components of the load equalizer assembly 290 are all 
different. There is an equalizer arm 300 specifically illustrated in FIGS. 
18, 20, 21, 25, 26, and 27, which is curved in a vertical plane. At the 
lower forward end 301 thereof, there is a step down central recess 302, 
first receiving a large diameter sway control friction disc 310, made of 
polyurethane, and then a smaller diameter sway control bearing 315, and 
then a depending shaft 306 of a lock lug 305. A retainer ring 320 retains 
the shaft or axle 306 in place in the step down central recess 302 of this 
equalizer arm 300. 
At the higher end 303 of this equalizer arm 300 is a hole 304 to receive 
the threaded lower end 346 of an equalizer bolt 345. The hole 304 is 
threaded, or a nut 307 is secured in line with the hole 304, to fasten 
this equalizer bolt 345 in place. The head 347 of this bolt 345 is large 
enough in diameter to provide a circumferential bearing surface 348 on the 
bottom of the bolt head 347. Also this equalizer arm 300 has a central 
longitudinally orientated recess 308, which during the hitching 
operations, accommodates the passage of the jack post or supporting leg 
220 of the trailer jack 216. 
The higher end 303 of the equalizer arm 300 is supported from the trailer 
tongue 54 by using one of several embodiments of an equalizer spring 
assembly 321. In the three spring embodiment 322, illustrated in FIGS. 18 
and 21, a bottom spring housing 325 has a lower transverse body 326 fitted 
on and between the converging members 53, 55 of a trailer tongue 54. On 
the top of this transverse body 326 are three spaced lower upstanding 
cylindrical receivers 327 to position the bottom portions of equalizer 
springs 335. They are made of a heavy duty rubber like shock absorbing 
material. The top portions of these hollow cylindrically formed equalizer 
springs 335 are positioned by top spring housing 330, having an upper 
transverse body 328, and three spaced upper depending cylindrical 
receivers 329. 
A two position transverse movement slider 340 is slidably placed on the 
upper transverse body 328, as shown in FIG. 18, and as indicated in FIG. 
21. How this slider 340 is specifically made is illustrated in FIGS. 43, 
44, and 45. There is a finger tab 341, a pair of higher elevation spaced 
supports 342, and a pair of lower elevation spaced supports 343, to 
respectively position the head 347 of the equalizer bolt 345, using the 
circumferential bearing surface 348 thereof. 
There are aligned central holes 331 in the top spring housing 330, and the 
bottom spring housing 325. The equalizer bolt is dropped down through the 
spaced supports 342, 343 of the slider 340, through the central hole 331 
in the top spring housing 330, through the hollow center of the center 
equalizer spring 335, through the central hole 331 in the bottom spring 
housing 330, through the hole 304 of the higher end 303 of the equalizer 
arm 30, and then threaded into the nut 307 on the equalizer arm 300. 
During assembly and adjustments of this load equalizer assembly 290, the 
bolt head 347 is supported on the lower elevation supports 343 of the 
equalizer slider 340. Then during the final positioning and subsequent 
tightening, the bolt head 347 is supported on the higher elevation 
supports 342 of the equalizer slider 340. 
Other Embodiments of Equalizer Springs, Housings Therefor and Sliders 
In addition to the three spring embodiment 322 shown in FIGS. 18 and 21 of 
an equalizer spring assembly 321 using the equalizer slider 340 
specifically shown in FIGS. 18, 21, 43, 44, 45, there are other 
embodiments of both equalizer spring assemblies 321 and equalizer sliders 
339. In FIGS. 19 and 20, the equalizer spring assembly 321, is referred to 
as a two equalizer spring assembly 323, having two spaced apart 
cylindrical equalizer springs 336, a two spring top housing 360 and a two 
spring bottom housing 365. 
In FIGS. 22, 23, 24, an equalizer spring assembly 321 is referred to as a 
one equalizer spring assembly 324, having one rectangular equalizer spring 
405, with a central hole 406 to receive the equalizer bolt 345. This 
spring 405 is received and supported by a channel shaped bottom spring 
housing 400, having upturned flanges 401 to position this spring 405, and 
having a centered hole 402 to accommodate the insertion of the equalizer 
bolt 345. 
The functions of an equalizer slider 339, in general, and the top spring 
housing 312, in general, are combined in what is called the integral 
channel combination 410 of the slider portion 411 and the top spring 
channel housing 412. This combination 410, also has a transverse elongated 
opening 413 to receive the equalizer bolt 345 in two relative transverse 
positions. Also this combination 410 receives the head 347 of the bolt 345 
at a lower elevation on top surface 414 of the top spring channel housing 
412 thereof, as shown in FIG. 23. Then this combination 410 has two spaced 
transverse upstanding supports 416 made integral with the top surface 414 
of the top spring channel housing 412 to receive the head 347 of the bolt 
345 at a higher elevation, as shown in FIG. 24, when this equalizer bolt 
345 is supporting the equalizer arm 300 at the higher end 303 thereof, 
where the nut 307 is preferably secured in place. During most of the time 
of the overall assembly time of this load equalizer assembly 290, the 
combination slider 410 is in the position illustrated in FIG. 23 
supporting the bolt head 347 at a lower elevation. At the conclusion of 
the hitching time of a towing vehicle to a towed vehicle, the combination 
slider 410 is in the position shown in FIG. 24, supporting the bolt head 
347 at a higher elevation, and consequently supporting the higher end 303 
of the equalizer arm 300 at a higher elevation, when the load is being 
equalized between the towing vehicle 24 and the towed vehicle 26. 
The Equalizing Arm 
The equalizer arm 300 of this overall self aligning trailer hitch 295 as 
stated previously, is specifically illustrated in FIGS. 25, 26, and 27. It 
is curved into a somewhat C shape, having a higher rear end 303 equipped 
with a threaded nut 307 and a hole 304 to receive and to hold the lower 
threaded end 345 of the equalizer bolt 345. A central longitudinal 
orientated recess 308 in this equalizer arm 300 accommodates the passage 
of the jack post 220 of a trailer jack 216, during hitching operations. 
At the lower forward end 301 of this equalizer arm 300 is the step down 
recess 302, having a larger diameter receiving space 309 at the top to 
position the sway control disk 310, and a lower depending smaller diameter 
receiving space 311 to position a cylindrical sway control bearing 315, in 
turn receiving a shaft 306 of a lock lug 305. 
The Lock Lug 
The lock lug 305 is specifically illustrated in FIGS. 28, 29, and 30. The 
lug portion 349, as shown in FIGS. 20 and 31, when in the inserted 
position thereof, locks the vertical rotatable claw 28 in the fully 
retaining position thereof, to firmly hold the lower ball 30 in the 
trailer load carrying position thereof. 
As also shown in FIG. 31, a claw adjusting screw 370, is threadably 
positioned in the vertical rotatable claw 28 to bear against the lug 
portion 349. This claw adjusting screw 370 is positioned, to in turn 
position the spherical partial recess 36 of the vertical rotatable claw 28 
as snugly and as fully as possible against the lower ball 30 during the 
full hitching position of the components of this load equalizer assembly 
290. Adjustment of this screw 370 is used in creating a tolerance and 
later to compensate for wear. 
The transverse hole 351 in the lug portion 349 receives the quick pin 132 
which holds the lug portion 350 in place in the hitch head body 80. 
The lock lug 305 has the integral bearing and positioning disk portion 352. 
The planar top surface 353 of this disk portion 352 has a slightly raised 
spacing and rubbing portion 354. Together they face upwardly to the bottom 
of the hitch head body 80. The planar bottom surface 356 of this disk 
portion 352 bears against the friction producing sway control disk 310. 
The lock lug 305 has the integral depending shaft 306 which passes through 
the sway control bearing 315 in the lower forward end 301 of the equalizer 
arm 300, as indicated in FIG. 21. When this depending shaft 306 is so 
positioned, a retainer ring 320 is snapped into place in the ring 
receiving groove 357 at the bottom of this depending shaft 306, as shown 
in FIG. 31. 
Different Embodiments of the Positioners of the Double Ball Having the 
Upper Ball and Lower Ball 
Because of different manufacturers making many components such as the 
inverted socket 52 secured to a trailer tongue 54, and also because of 
different towing loads being undertaken, several different embodiments of 
positioners of the double balls, or pair of balls 32, having the upper 
ball 34 and lower ball 30, are available. These various embodiments are 
illustrated in FIGS. 32 through 42. 
In FIGS. 32, 33, and 34, the "Atwood" socket assembly 371 is illustrated, 
showing how the "Atwood" styled assembly 372 of the pair of balls 32 
includes a secured horizontal rearward extending positioning bar 373, 
having a hole 374, and threaded nut secured to it, to receive a 
positioning bolt 359, passing down through a hole 376 in the "Atwood" 
socket assembly 371. 
In FIGS. 35, 36, and 37, the "Franklin" socket assembly 377 is illustrated, 
showing how the "Franklin" styled assembly 378 of the pair of balls 32 
includes a secured horizontal rearward extending positioning bar 379, 
having an upstanding vertical positioning bar 378 secured to the rearward 
end 381 of this horizontal positioning bar 379, and equipped with two 
alike spaced threaded holes 382. Two positioning bolts 383, each with a 
washer 384, are dropped down through holes 385 in the "Franklin" socket 
assembly 377 and threaded into the holes 382 to secure in place this 
"Franklin" styled assembly 378. 
In FIGS. 38, 39, and 40, the so called "Bulldog" socket assembly 386 is 
illustrated, showing how the "Bulldog" styled assembly 380 of the pair of 
balls 30 and 34 includes a secured horizontal rearward extending 
positioning bar 388, having like spaced receiving holes 389 at the 
rearward end 390 thereof. A U shaped threaded clamp fastener 391 with the 
two alike nuts 392, is used to secure this "Bulldog" styled assembly of 
the paired balls 380 to the "Bulldog" socket assembly 386. 
In FIGS. 41 and 42, again in respect to illustrating an "Atwood" socket 
assembly 371, but other such assemblies could be considered, is shown in 
conjunction with a high towing load styled assembly 393. This very strong 
assembly 393, includes the pair of balls 355 built to handle a ten 
thousand pound towing load and having a secured horizontal positioner bar 
394 as shown in FIGS. 19 and 20. This bar 394 in turn is secured to 
positioning bracket 395 having rearwardly diverging legs 396, 397 to 
extend respectively along the converging frame members 53, 55 of the 
trailer tongue 54, and be bolted in place using holes 398. 
The Assembly of the Load Equalizer Assembly and the Overall Self Aligning 
Trailer Hitch 
At the very outset of the preparation of the towing vehicle 24, the same 
preparations will be undertaken, as occur when the other embodiment 20 of 
the self aligning trailer hitch is to be utilized. The towing vehicle 24 
is equipped with a draft bar assembly 62 also referred to as a tow bar 
assembly 62 having an extending tube 60, also referred to as a receiver 
60. These assemblies include a T shaped tow bar 64 having a horizontal leg 
66 and a vertical leg 72, as shown in FIGS. 1, 2, and 3, and FIGS. 18, 19, 
20, and 21. The hitch head body 80 is adjustably secured to the vertical 
leg 72 at the right height in respect to the particular towed vehicle 26, 
often a trailer 26. Included with the hitch head body 80 is the vertical 
rotatable claw 28, and the ball guiding ramp 38. The major components with 
their respective fasteners include all the components which are carried by 
the towing vehicle 24, before the hitching operation begins. 
The components of the balance of this overall self aligning trailer hitch 
295, having this load equalizer assembly 290, are secured to the trailer 
tongue 54 to be carried by the towed vehicle 26, before the hitching 
operation begins. The various embodiments of these components are selected 
depending on what the towing loads will be, and what manufacturer's 
components have already been installed on the towed vehicle 54, such as 
the "Atwood", "Franklin", and "Bulldog" components. 
The pair 32 of the upper ball 34 and lower ball 30, or the pair 355 of 
stronger balls are inserted, via the respective upper balls, into the 
respectively selected inverted sockets 52, 371, 377, or 386. Their 
respective positioners are secured to "Atwood", "Franklin", or "Bulldog", 
components, or to the tongue 54 of the trailer 26 or towed vehicle 26. 
Then the equalizing arm 300 is secured at the higher rear end 303 thereof 
to the tongue 54 of the towed vehicle 26, using the equalizer bolt 340, 
and a selected equalizer spring embodiment. The lower forward end 301 is 
fitted with the sway control bearing 315, the sway control disc 301, and 
the lock lug 305. 
At this time the towed vehicle, located preferably on a level or near level 
ground area, has the wheels thereof well blocked. Then the towing vehicle 
24 is backed slowly until the vertical rotating claw, via the guiding ramp 
38, receives the lower ball 30, then traveling in a horizontal direction, 
and moves this ball 30 in a vertical arc to an over center hitched 
location. The towing vehicle 24 is stopped and held in position by brakes, 
and either a low gear shift location, or a park automatic transmission 
position. 
Thereafter the trailer jack is utilized to raise the tongue 54 of the towed 
vehicle 26, and consequently raise the rear of the towing vehicle, as 
shown in FIG. 15. While these various components remain in their raised 
positions, and the bolt head 347 of the equalizer bolt 345 is in the lower 
position thereof, the lug portion 349 of the lock lug 305 is inserted into 
the hitch head body 80 to lock the rotatable claw in position. The quick 
pin 132 is inserted to maintain this positioning of the lug portion 349, 
indirectly the positioning of the vertical rotatable claw 28, thereby 
assuring the direct ball and socket coupling of the towed vehicle 26 to 
the towing vehicle 24. 
Then the trailer jack 216, via turning of the handle 218 thereof is 
operated to withdraw the jack post 220 to its full road clearance 
position, transferring all the loads to the self aligning trailer 29. 
Thereafter the selected equalizer slider 339 is moved to position the bolt 
head 347 to the higher elevation thereof, and then the bolt is tightened 
to complete the load equalizing provided by using this load equalizing 
assembly 290. 
After the first hitching of a towed vehicle 26 to a towing vehicle, and if 
these same vehicles are again to be hitched together, then most of the 
assembly steps first undertaken do not have to be repeated again. When 
these vehicles are to be separated, yet soon to be hitched together, and 
they are on level ground, brakes on, low gear in place, or park position 
completed, towed vehicle wheels blocked, then the trailer jack is utilized 
to raise the hitching components. Thereafter the quick pin 132 is removed, 
the lug portion 349 is removed and the load equalizer assembly 290 is 
cleared. Thereafter the trailer jack is lowered so the lower ball 30 will 
readily clear from the hitch head body 80, upon the reverse rotation of 
the vertical rotatable claw 28, when the towing vehicle 24 is moved 
forward. 
At all times if safety chains are utilized they will be secured in place 
before the hitched vehicles are moved. Later, they will be unfastened 
before the towing vehicle 24 is to be moved forward during the final 
unhitching procedures. 
As illustrated in FIGS. 20 and 31, the common vertical center line of the 
upper ball 34 and lower ball 32 remains just forward of the center of 
rotation of the vertical rotatable claw 28. Also the vertical center line 
of the lower forward end 301 of the equalizer arm 300 is the same vertical 
center line of the step down recess 302 thereof, the center line of the 
sway control disk 310, the center line of the sway control bearing, and 
the center line of the depending shaft 306 of the lock lug 305, and this 
overall vertical center line remains just spaced from the common vertical 
center line of the upper ball 34 and the lower ball 32. This grouping of 
these components in respect to these vertical center lines insures the 
overall good operational performance of this overall self aligning trailer 
hitch 295 utilizing this load equalizer assembly 290.