Abstract: The present invention relates to a three-point implement mounting (10) for an agricultural or industrial utility vehicle (28), having an upper member (14) and two lower members (12). It is possible for a working implement (42) to be coupled to the three-point implement mounting (10) in order to couple the working implement (42) to the utility vehicle (28). In order to specify an interface between the utility vehicle (28) and the working implement (42) which is versatile and can, in terms of its properties, be varied or adapted to the physical application, it is proposed that the three-point implement mounting (10) is of modular design and in that the three-point implement mounting (10) has a coupling interface (26), by means of which the three-point implement mounting (10) can be coupled to the utility vehicle (28). The present invention also relates to an industrial or agricultural utility vehicle (28), a working implement and a storage system.

Abstract: The invention relates to a lower link assembly for a tractor hitch. The lower link assembly includes a first strut and a second strut. The first strut includes a channel at an end thereof and a hollow space defining first and second walls and adjacent to the channel. The second strut may be inserted into the channel. A locking element is associated with the hollow space for latching the second strut to the first strut, and may be moved between an unlocked position and a latching position. A spring pretensions the locking element in the latching position. A grip element is connected to the locking element, by means of which an operator may move the locking element into the unlocked position. The spring is biased to retain the locking element in the hollow space.

Abstract: A ball/socket link end assembly includes a link opening formed in the link end. A portion of the opening forms a spherical inner surface. A pair of ball entry slots are formed in the link end. The slots are spaced apart and positioned on opposite sides of the opening, and extend only part way into the link end from one side thereof. The assembly also includes a removable truncated ball member with a spherical perimeter which matches the spherical inner surface. A clamp member is attachable to the link end. The clamp member is engagable with the ball to prevent removal of the ball from the link end when the ball is aligned with the entry slots. The clamp member is received in a recess formed in the link end adjacent to the opening.

Abstract: A quick coupler has a frame with a hook, and an operator movable control bar. The hook has a recess for receiving a hitch pin. A latch mechanism includes a latch, a one-piece trigger, a spring, and a stop fixed to the coupler frame. The latch is pivotally coupled to the frame and moves to open and closed positions permitting and preventing the hitch pin to move into and out of the hook recess. The trigger is pivotally coupled only to the latch and to the control bar. The trigger engages the hitch pin and moves the latch to the open position. When the hitch pin is in the hook recess, the stop engages the trigger and prevents the latch from moving to its open position. A central portion of the trigger is pivotally coupled to a central portion of the latch. A shoulder surface is formed in a lower end of the latch, and a tab projects from an end of the trigger. The tab engages the shoulder surface to limit pivoting of the latch to its open position when the trigger engages the stop.

Abstract: A tractor of the present invention can reduce a manufacturing cost of a lift arm support body. The tractor is configured such that a lift arm is mounted on an upper portion of a transmission casing by way of a lift arm support body, the lift arm is hydraulically controllable by a hydraulic control valve by way of a hydraulic circuit body, and the hydraulic circuit body and the hydraulic control valve are fixed to the transmission casing as bodies separate from a lift arm support body.

Abstract: A hitch release system for releasing the locked engagement of a hitch, the hitch having a manually operable release bar coupled to a locking mechanism, the hitch release system includes a selectively actuatable power assist system, the power assist system being releasably, operably coupled to the release bar, wherein actuation of the power assist system acts to translate the release bar in a first axial direction, such translation acting to release the locking mechanism. A method of release is further included.

Abstract: Embodiments of the present invention comprise a system for positioning a drawn implement being pulled by a vehicle traveling generally along a desired path of movement, the vehicle having a mounting hitch on the rear end thereof where a system hitch is configured to adjust its angular orientation relative to the vehicle mounting hitch and a global positioning system receiver operable to detect the position of the implement relative to the desired path as the vehicle moves generally along the desired path and generate a signal that is indicative of the lateral position of the implement relative to the desired path and means for controlling the hitch means to adjust the angular orientation of the hitch means so that the implement follows the desired path of movement in response to the global positioning system signals.

Abstract: The present invention provides an apparatus and methods for connecting an attachment to a hitch system of a vehicle. The apparatus comprises means for connecting the apparatus to a hitch system and means for connecting the apparatus to an attachment, such as a plow or scraper. The present invention allows the attachment to be extended behind, offset to, or pivoted relative to the vehicle. In addition, the present invention allows multiple attachments to be connected to a vehicle by way of its hitch system.

Abstract: A coupling assembly for use with a tractor having a three point mounting hitch assembly having two extension legs telescopically retained by two generally vertical sleeve members slanted towards each other and two lateral extension arms telescopically retained by a cross sleeve member, wherein the lateral extension arms can be extended or retracted and wherein the extension legs can be extended or retracted to alter the relative positions of an upper hook and two lower hooks.

Abstract: The present invention relates to an upper link (32) for a utility vehicle, in particular for an agricultural tractor. The upper link (32) has a hydraulic cylinder (34) for adjusting the upper link (32). Furthermore at least one fluid tank (36), to which the hydraulic cylinder (34) can be coupled, is provided so that in the coupled condition hydraulic fluid limited to a pre-determined volume can be exchanged between the hydraulic cylinder (34) and the fluid tank (36) and so that a piston (40) of the hydraulic cylinder (34) can move in floating fashion by a distance (ls) corresponding to the pre-determined volume in the hydraulic cylinder (34). Furthermore the present invention relates to a front-end as well as to a back-end three-point hitch of a utility vehicle with two pivotally connected lower links and an upper link with such a fluid tank.

Abstract: A coupler for a hitch such as a quick hitch for a three point hitch of a work machine such as a tractor or the like, having a latching mechanism for holding a pin of a work element such as an implement or the like, in a receptacle of the coupler, which latching mechanism is self-latching and provides a self-locking capability when latched to hold the pin in the coupler, in opposition to, and in response to, forces and movements of the pin in directions for normally opening the coupler.

Abstract: A hydraulic system for an attachment for a tractor is disclosed. The hitch has a frame having a top member and a bottom member. The top and bottom members are joined together by a pair of side members forming a structure with an orifice. Each of the top and bottom members are hollow in a cross section, as are each of the side members so that a fluid contained in the members can flow from one member to another.

Abstract: The present invention relates to an apparatus for coupling an implement to a working vehicle, having two lower link bars, a length-adjustable upper link bar, and two lifting elements. The end closest to the working vehicle, of each of the lower link bars and the upper link bar, is swingably mountable, and the other end closest to the implement is likewise swingably mountable. The upper link bar is essentially disposed centrally in the upper region of the coupling apparatus. The two lower link bars are disposed essentially laterally in the lower region of the coupling apparatus. One end of each of the lifting elements can be swingably mounted on a respective lower link bar. A supported load from the implement which acts on the working vehicle does not lead to diminishment of the load on a vehicle axle.

Abstract: A snowplow frame to three-point hitch adapter includes an adapter frame having a first and a second side, each side generally parallel to one another. The first side includes a number of interconnection points sized and located to generally match the interconnection points between a snowplow and a snowplow frame, while the second side includes a number of interconnection points sized and located to generally match with the interconnection points on a three-point hitch configured tractor implement.

Abstract: A utility vehicle includes front and rear wheel assemblies, a frame supported on the front and rear wheel assemblies, and an operator compartment supported on the frame and having operator controls. The frame includes a central, tubular frame member having a front end portion and a rear end portion. An engine is supported on the frame for providing power to the front and rear wheel assemblies. A cooling assembly mounted above the engine. An attachment arm is attached to the front portion of the frame and a rear interface mount is rigidly attached to the rear portion of the frame.

Abstract: A hydraulic maneuvered draw bar hitch assembly for a safe connection from a three-point hitch on a farm tractor to the normal vertical pin in the clevis assembly of a towed farm vehicle which entraps the clevis pin, by sliding a male protruded apparatus horizontally behind the aforementioned pin through the female orifice mounted on the main drawbar where it is held closed by the hydraulic power assembly in an engaged position until the operator decides to disengage the clevis pin by withdrawing the male protrusion from the female orifice.

Abstract: A pull-type crop harvesting machine has a header carried on a frame mounted on ground wheels with a hitch arm extending from the frame over the header to a hitch connector of a tractor. The hitch arm is mounted for pivotal movement about a generally upright axis such that in a first position the tractor tows the frame in echelon to one side and in a second position the tractor tows the frame in echelon. There is provided connecting assembly for connecting the forward end of the hitch arm to a hitch connector of the tractor and a mechanical connection from the PTO of the tractor to a pump for hydraulically driving the cutting assembly. The connecting assembly provides three axes of pivotal movement for up and down, tilting and side to side movement of the header relative to the tractor.

Abstract: The invention relates to a device for a coupling an agricultural implement to an agricultural tractor, in which the operation to release the coupling between the agricultural implement and the agricultural tractor can be easily implemented. When the coupling of the agricultural tractor and the agricultural implement is released, first, a control lever of a coupling hook is slid upward against the urging force of a spring until a second guide pin reaches the lower end of a slit. Next, the control lever is turned forward around the second guide pin until a bent portion of the upper portion and the lower portion of the control lever comes into contact with a first guide pin. As a result, the rear end of a stopper is retracted into a cavity in the hook main body of the device through a second opening so as to slide to the coupling-ball-releasing position, and a groove of the stopper is hooked to a hooking pin so as to be fixed.

Abstract: A trailer for hauling cylindrical bales includes a carrier for the bales, wheels on the carrier, an elevation adjustment mechanism for raising and lowering the carrier, and a hitch for coupling to a towing vehicle. The carrier has two inwardly extending bottom flanges that are spaced apart and define an opening between them, and an open end through which the bales pass during loading and unloading. When moving the carrier into engagement with one of the bales resting on the ground, the bale stays generally still due to friction from the bale contacting the ground through the opening and the bottom flanges slide under the bale to load the bale onto the carrier. Additional aspects include an adapter for use with a towing vehicle having a three-point pintle hitch, insert containers that fit into the trailer, and a method of loading and unloading the bales.

Abstract: A tracking hitch assembly couples to the drawbar of the tractor in a conventional manner. To prevent the hitch from pivoting with respect to the drawbar, the hitch includes an adjustable hitch stabilizer which engages the lift arms of the tractor. When a pivoting force is exerted against the hitch, one lift arm is placed in tension, and the other lift arm is placed in compression. Thus the hitch is prevented from pivoting with respect to the drawbar.

Abstract: A self-contained hitch and control assembly comprising a portable power unit including a gas engine, hydraulic pump and associated conduits and valves. A hitch apparatus includes a frame carrying a compatible hitch and a pair of connecting arms with a third arm above and between the pair of arms. A hydraulic cylinder both raises and lowers the arms and a power takeoff is driven by the power unit in one and opposite directions.

Abstract: A hitch assembly for use between a prime mover having a pair of moveable arms and a trailed vehicle. The hitch assembly includes a transverse member attached by a pivot attachment to each movable arm at spaced locations on the transverse member. Each of the movable arms is pivotable about a horizontal axis defined by the transverse member. A pivot connection connects the transverse member and a frame member or draw bar of the trailed vehicle. The transverse member pivots with respect to the frame member or drawbar about a vertical axis and a horizontal axis defined by the direction of travel.

Abstract: Towing apparatuses suited for use with, for example, three-point hitches or quick hitches. At least some of the present towing apparatuses include a male hitch member that is positioned such that a force acting through the male hitch member (such as a force transmitted to the male hitch member through the female hitch member of the structure being towed) does not cause the particular towing apparatus to rotate about an axis along which the towing apparatus is pivotally coupled to a towing vehicle (such as through a three-point hitch or a quick hitch).

Abstract: An implement support unit for cooperating with an implement-mounting device for an implement for mounting the implement on a trailer unit. Preferably, the support unit is a three point hitch type support unit.

Abstract: A device for coupling two units to each other with at least five connecting elements (18,20,22,24,26) whereby the respective first end thereof can be hingeably connected to respectively one connection point (30,32,34,36,38) of one unit and whose other end can be hingeably connected to a respective connection point (40,42,44,46,48) of the other unit. One length-adjustable connecting element (18) is exclusively provided, the element being arranged in a substantially central position in the upper area of the device (12). Two connecting elements (24,26) are provided in the lower area of the device (12). Two length-adjustable connectable elements (20,22) are coupled substantially at the connection point (36;38) of a connecting element (24,26) arranged in the lower area of the device (12) on one unit, and in a lower area (42,4?) of the other unit. A length-adjustable stabilizer element (28) is also provided.

Abstract: An coupling mechanism includes a cross member, left and right side members projecting from the cross member, and a pair of attaching members which are removably attached to the side members. Each attaching member has an elongated body, a first hook fixed to a first end of the body, and a second hook fixed to a second end of the body. The first hook has at least one dimensional feature which is smaller than a corresponding dimensional feature of the second hook. Each attaching member is mountable in a corresponding one of the side members in a first orientation with the first hook in an operative position and is mountable in a second orientation with the second hook in an operative position. A longer portion of each attaching member projects from a lower end of the corresponding side member when the attaching member is mounted in the first orientation.

Abstract: An adjustable link assembly includes a pair of coupling yokes, each having a threaded rod projecting therefrom. First and second lock members projecting from the corresponding first and second yokes. The first and second yokes are threadably coupled to opposite ends of a threaded central body. The body has a central non-cylindrical adjusting portion located between first and second indexing portions. A bracket is slidable over the body. The bracket is rotatable with respect to the body when the bracket is positioned over the indexing portions and being non-rotatably coupled to the body when the bracket is positioned over the central adjusting portion. A lever is pivotally coupled to the bracket so that an end of the lever may be coupled to either of the lock members to prevent rotation of the central body relative to the yokes.

Abstract: A combination of a tractor hydraulic arm assembly and a hitch adapter installed between the two arms of the arm assembly, the hitch adapter consisting of a length of “U” shaped steel channel, having a plurality of holes formed in the top surface, with trailer hitches mounted in the holes and a steel shaft fastened to the underside of the channel and a yoke mounted on each end of the channel. The steel shaft is mounted in holes formed in the arm assembly and locked in place with implement clips, with the yolks straddling the two arms to prevent rotation of the channel.

Abstract: A three-point apparatus is disclosed comprising a hitch system, an implement, and a suspension system. The hitch system is comprised of a base and a three-point interface. The base of hitch system is coupled to the three-point interface of the hitch system. The three-point interface is configured to connect to a three-point system, such as the three-point arms of a tractor. The suspension system is coupled between the base of the hitch system and the implement.

Abstract: A working machine lifting device of a tractor, comprising externally installed hydraulic lift cylinders disposed on the right and left sides of a transmission casing, lift arms rotated by the operation of the cylinders, and lower links vertically rotated by the rotation of the lift arms and connected to a working machine, wherein the cylinder and the lower link are rotatably supported on a same pin supported by the transmission casing and a sway chain bracket, and the support point of the cylinder and the vertical rotating pivot of the lower link are positioned on the axis of the pin.

Abstract: A control system controls a three point implement hitch assembly of a tractor. The three point implement hitch assembly includes an upper link and two lower links. The upper link includes an adjustable length double acting hydraulic unit. The position of each lower link is controlled by an adjustable length double acting hydraulic unit. A hydraulic circuit controls communication between the hydraulic units, a hydraulic supply and a hydraulic tank. The circuit permits each hydraulic unit to be controlled independently of one another.

Abstract: A device for controlling the position of a mountable implement relative to an implement carrier vehicle has a mountable implement (2, 3, 4) which can be moved at a predetermined height by the implement carrier 1 following the ground. A support element (11, 19, 20), is coupled to the mountable implement (2, 3, 4) and can be attached to the implement carrier vehicle (1). A coupling device (15, 17, 18), is connected to the mountable implement (2, 3, 4) and to the support element (11, 19, 20). The mountable implement (2, 3, 4) is freely adjusted to a lifting position corresponding to the height path relative to the support element (11, 19, 20). An attachment device (6, 7, 8) attaches the support element (11, 19, 20) to the implement carrier vehicle 1 having a lifting device. A sensor determines the actual lifting position of the mountable implement (2, 3, 4) relative to the support element (11, 19, 20). A control device determines the deviation of the actual lifting position from a desired lifting position.

Abstract: Hitch mount assembly for snow blades or other accessories or implements for off-road vehicles such as all-terrain vehicles. The assembly includes a receiver for mounting to the vehicle chassis and an implement assembly readily removably coupled to the receiver. The configuration of the receiver and implement assembly allows for self-alignment during the mounting operation. A switching mechanism and actuator also can be used to pivot the working implement remotely. The mount assembly can be attached to the vehicle with a powered winch or manually.

Abstract: A self-propelled agricultural vehicle is constructed by assembling the parts of a standard row-crop tractor to the point where the next step is that of mounting the cab to the chassis. At this point, a cab adapter module is mounted to the chassis using the mounting points normally used for mounting the cab to the chassis. The cab, provided in a form without the usual access ladder and fenders, is mounted to the cab adapter module so as to face in a direction opposite to that which it would face if mounted to the chassis. The seat and all controls for operating the tractor remain in the same locations in the cab regardless which direction the cab faces. Minor reconfigurations of hydraulic circuitry and the differential are required for permitting the vehicle to be operated in a forward direction opposite to that for the operation of the standard tractor.

Abstract: A hitch control system controls a vehicle hitch to which implements can be attached. The hitch control system includes a spring-centered primary command lever which is manually moveable from a centered position to deflected positions, and which automatically returns to the centered position when released from a deflected position. A control unit generates a hitch command signal in part as a function of the lever position. The control unit has a closed-loop control mode wherein the valve command signal is generated in response to parameter, such as position and draft force, and the hitch command signal. The control unit moves the hitch in a step-wise manner by a predetermined amount in response to momentary deflection of the command lever to one of the deflected positions, and the amount of hitch movement is independent of an amount and duration of deflection of the command lever if the duration is not more than a predetermined duration.

Abstract: A farm implement of a tractor is hitched to two lift arms, each of which is moved by a respective actuating cylinder having two chambers connected to a feed circuit supplying a pressurized fluid; the feed circuit having, for each chamber, two feed lines for feeding the fluid to and from the chamber respectively, and four independent valves, each located along one of the feed lines and movable between a closed position and at least one open position respectively closing and opening the relative feed line.

Abstract: A coupling mechanism for a work vehicle includes a coupler frame for mounting to the work vehicle and a pair of dual hook members mountable on the frame. Each dual hook member has a body with first and second hooks projecting from opposite ends the body. The ends of the body define a body plane extending therebetween. The first and second hooks project on the same side of the body plane. Each hook forms a coupling recess, and each of the recesses opens away from the body plane. The first hook is smaller than the second hook. The dual hook member is mountable in a first orientation wherein the first hook is in an operative position and is mountable in a second orientation wherein the second hook is in an operative position.

Abstract: A controlled articulation trailer with synchronized steering and a traveling top link three point tool bar hitch is disclosed. The controlled articulation trailer comprises a box-frame carriage having two separate but laterally aligned, wheeled axles near the back of the carriage. The aligned axles are mechanically angularly controlled by, or ‘synchronized to’, the movements of the draft vehicle. A tongue attaches to the draft vehicle via a hitch plate bolted to the draw bar of the draft vehicle. The tongue receiver fits onto a ball hitch and an adjustable stabilizer arm is bolted to the hitch plate and extends at an angle back to a tongue attachment. The tongue connects through the front of the carriage to a pivot point located on a bridge across the front-middle of the carriage and extends beyond this pivot point to connect, through doubly-pivoting tie-rods, to the wheels, thus controlling the articulation such that the trailer's wheels turn in synchronization to turns made by the draft vehicle.

Abstract: An implement quick coupling mechanism for a work vehicle includes a frame having a cross member and left and right side members projecting from the cross member. The cross member and side members have mounting parts which permit different implement coupling parts to be mounted thereon. A first set of hook members having a first type of dimensional characteristics may be mounted on the frame to form a first category of coupling mechanism. A second set of coupling members having a second type of dimensional characteristics may be mounted on the frame to form a second category of coupling mechanism.

Abstract: A hydraulic system for an attachment for a tractor is disclosed. The hitch has a frame having a top member and a bottom member. The top and bottom members are joined together by a pair of side members forming a structure with an orifice. Each of the top and bottom members are hollow in a cross section, as are each of the side members so that a fluid contained in the members can flow from one member to another.

Abstract: A hitch assembly includes a base member, an extension arm and an A-frame for supporting any of a plurality of implements. An elevating cylinder is connected to raise and lower the extension arm. Additionally, lateral cylinders are synchronized to move in unison to pivot the hitch assembly laterally side to side. The first respective ports of the lateral cylinders are directly connected together facilitate synchronous movement. A universal joint is connected between the arm and A-frame to coordinate up and down and left and right movement of the hitch assembly.

Abstract: A three-point hitch suitable for operation with wide implements is constructed by substituting a pair of flotation actuators for the usual drop links that are normally coupled between a pair of rocker arms and a pair of lower draft links. These drop links are coupled to a hydraulic circuit including, according to one embodiment, individual accumulators for each flotation actuator, and according to a second embodiment, both actuators are coupled to a single accumulator. The accumulator(s) act to cause a pre-selected lifting force to be exerted by the flotation actuators so that a predetermined amount of the weight of an implement mounted to the draft links is counterbalanced, leaving a desired ground pressure being exerted by the implement during operation. When using individual accumulators, a side-to-side weight balance can be achieved since different accumulator settings may be used.

Abstract: An apparatus for automatically linking a drive member of a power source and a driven member of an implement, includes two attachment pieces, one attached to the power source, and the other attached to the implement, and an attachment mechanism for automatically connecting the two attachment pieces whereby the drive member and the driven member are operably coupled.

Abstract: A three point hitch for a cart-type utility vehicle wherein the utility vehicle comprises a vehicle frame that includes an axle housing and an upper frame cross member. The three point hitch comprises a pair of spaced apart lower draft links, each pivotally mounted to the axle housing and extending rearward, the lower draft links having connection features at free ends thereof for connecting to an implement. A beam extends in a lateral direction parallel to the upper frame cross member. A rockshaft extends parallel to the beam and is pivotally connected to the beam. A lift bracket is fixedly connected to the rockshaft. Two upper links are fixedly connected to the rockshaft and extend rearward, the upper links located above the lower draft links. Two vertical links connect the upper links and the lower draft links. Endplates are fixedly connected to the beam and are connected to the vehicle frame by pins that also are used to pivotally connect a cargo box or platform to the frame.

Abstract: A three-point hitch suitable for operation with wide implements is constructed by substituting a pair of flotation actuators for the usual drop links that are normally coupled between a pair of rocker arms and a pair of lower draft links. These drop links are coupled to a hydraulic circuit including, according to one embodiment, individual accumulators for each flotation actuator, and according to a second embodiment, both actuators are coupled to a single accumulator. The accumulator(s) act to cause a pre-selected lifting force to be exerted by the flotation actuators so that a predetermined amount of the weight of an implement mounted to the draft links is counterbalanced, leaving a desired ground pressure being exerted by the implement during operation. When using individual accumulators, a side-to-side weight balance can be achieved since different accumulator settings may be used.

Abstract: An implement quick coupling mechanism for a work vehicle includes a frame having a cross member and left and right side members projecting from the cross memeber. The cross member and side members have mounting parts which permit different implement coupling parts to be mounted thereon. A first set of hook members having a first type of dimensional characteristics may be mounted on the fram to form a first category of coupling mechanism. A second set of coupling members having a second type of dimensional characteristics may be mounted on the frame to form a second category of coupling mechanism.

Abstract: A farm implement of a tractor is hitched to two lift arms, each of which is moved by a respective actuating cylinder having two chambers connected to a feed circuit supplying a pressurized fluid; the feed circuit having, for each chamber, two feed lines for feeding the fluid to and from the chamber respectively, and four independent valves, each located along one of the feed lines and movable between a closed position and at least one open position respectively closing and opening the relative feed line.

Abstract: The present invention provides an implement mounting fixture for mounting an implement to a work machine. The implement mounting fixture includes a frame having a hitch tube for mounting to a work machine. A pair of upper lift arms extend outwardly from the frame on opposite sides of a transverse beam. A cylinder extends from a lower portion of the frame to the transverse beam such that a force applied by the cylinder causes the upper lift arms to pivot with respect to the frame. A link arm is pivotally connected to the frame for linking to an implement.

Abstract: A strut is provided for a three-point hitch device used to attach farm implements to an agricultural tractor. The strut is substantially symmetrical with respect to a longitudinal axis of symmetry, and has a system for adjusting its length along the axis. The adjusting system has fast, discrete length adjustment devices, and two infinite length adjustment devices. The two infinite length adjustment devices are located on opposite sides of a dividing member positioned crosswise to the axis of the strut.

Abstract: A hitch assembly is mounted on a frame of an agricultural tractor. The hitch assembly includes a pair of draft links pivotally mounted on the frame, a drawbar support fixed to the frame between the draft links, and a pair of sway blocks fixed to opposite sides of the frame. Each sway block has an upper end fixed to a side of the frame and extends generally downwardly to a lower free end. The lower free end of each sway block is positioned below a plane defined by a bottom surface of the drawbar support. Each sway block is preferably tapered from a wider front side to a narrower rear side to form an inner surface which faces inwardly and rearwardly. A wedge plate is mounted beneath the drawbar support. The plate extends generally laterally from a left end surface to a right end surface, and each end surface is slanted in order to matingly engage the inner surface of a corresponding one of the sway blocks.