A Tow Hitch for a Working Vehicle

Abstract

A working machine comprises a rear mounted tow hitch 20 comprising a tow hitch arm 21 mounted to the rear 19 of a working vehicle, being pivotable between: a first position (fig. 2a) wherein the tow h

Description

FIELD This invention relates to a tow hitch for a working vehicle. In particular, it relates to a tow hitch which is deployable from a stowed position to a towing position. BACKGROUND Known working vehicles utilise tow hitches to attach various forms of trailed units such as a transportation trailer or trailed implement. An example of a tow hitch on a working vehicle is provided in EP3257689, which discloses a retractable tow hitch on a back hoe loader. The solution provided in EP3257689 involves a tow hitch arrangement having a body for mounting the tow hitch arrangement relative to an associated vehicle. The tow hitch arrangement includes a first member rotatably mounted relative to the body and a second member slideably mounted relative to the first member, the second member including a tow hitch. The tow hitch arrangement has a stored position in which the first member is in a first rotational position relative to the body and the second member is in a first longitudinal position relative to the first member. A deployed position of the tow hitch provides the first member in a second rotational position relative to the body and the second member in a second longitudinal position relative to the first member. In the illustrated embodiment, the tow hitch is stored above the retracted position of the stabiliser legs and so does not materially affect the ground clearance of the machine. Thus, there is provided a tow hitch which can be stowed underneath the rear of the chassis in a convenient location and which can be rotated out and extended for use. The present disclosure seeks to provide an improved tow hitch arrangement. SUMMARY The present invention provides a working machine. A first aspect of the disclosure provides a working vehicle comprising: a chassis; an operator structure mounted to the chassis; a ground engaging structure mounted to the chassis; and a prime mover for providing motive power to the ground engaging structure. The working machine may comprise a working arm pivotally mounted to the chassis. The working machine comprises a rear mounted tow hitch arrangement comprising: a tow hitch member pivotably mounted to a rear body portion of the working vehicle at a first end and comprising a tow hitch at a second end. The tow hitch member may be pivotable between: a stowed position in which the tow hitch is housed within the rear body portion; and, a towing position in which the tow hitch is external to the rear body portion and configured retain a tow hitch of a trailer to be towed. Providing a working machine with a pivotable tow hitch member having a tow hitch at second end thereof, allows the tow hitch to be pivotably moved between a stowed and towing position. This provides a convenient way of including a tow hitch on a working machine which allows the departure angle of the working machine to be unhindered when the tow hitch is not in use. The tow hitch member may be elongate and extend in the fore-aft direction of the working vehicle. The tow hitch member may be connected to the working machine via a pivot mount located fore of the tow hitch. The working machine may further comprise an actuation arrangement configured to move the tow hitch between the stowed and towing positions. The actuation arrangement may comprise a one or more hydraulic cylinders. The hydraulic cylinders may be conventional and be configured to raise the tow hitch member when extending and lower the tow hitch member when retracting. There may be first and second hydraulic cylinders mounted on either side of the tow hitch member. The tow hitch member may be further pivotable into a lowermost loading position in which the tow hitch is external to the rear body portion and positioned to receive a tow hitch of a trailed unit to be towed. The lowermost loading position may be defined by the full extent of the actuation arrangement. The lowermost loading position may be defined between a ground surface plane on which the working machine rests and the towing position. An underside of the rear body portion may define an upwardly angled portion which defines the angle at which the machine can be orientated in relation to a rearward ground surface. This angle may be referred to as the departure angle. The tow hitch may be located inboard of the upwardly angled portion, that is, internally and above the upwardly angled portion and within the rear body portion, when in the stowed position. The tow hitch may be outboard of the upwardly angled portion when in the towing position, or lowermost loading position. The tow hitch may be external of the rear body portion to the extent it can freely engage with a hitch of a trailed unit when in the towing position. An underside of the tow hitch member may project from the rear body portion so as to at least partially define the departure angle when in the stowed position, thereby providing a rigid contact point on the underside of the machine and providing some protection for the body panels of the rear body portion or components housed within the rear body portion. The upwardly angled portion and / or tow hitch member may define plane which extends upwardly rearward and between lateral portions of the rear body portion. The tow hitch member be longitudinal and configured to pivot in a plane parallel to a principal axis of the working machine (i.e. the fore-aft axis of the machine). The actuation arrangement may comprise one or more linear actuators, e.g. a hydraulic cylinder, which is linearly extendable to pivot the tow hitch between the stowed and towing positions. The linear actuator may be configured to raise the tow hitch from the lowermost loading position when a load is attached. The working machine may further comprises a latch assembly movable between a first engaged position and a second released position, wherein the tow hitch is restrained from being lowered using the actuation arrangement when in the engaged first position, and is free to be lowered using the actuation arrangement when in the second released position. The latch assembly may comprise a latch arm mounted to the chassis and a latch member mounted to the tow hitch member. The latch arm and latch member may be releasably engageable to provide the mechanical restraint. The releasable engagement is provided by pivoting the latch arm or latch member relative to the other of the latch arm and latch member. The latch arm may be pivotably mounted to the chassis, and the latch member mounted to the tow hitch member. The latch arm may extend downwardly from the rear body portion and be configured to move between an extended position and a retracted position. The extended and retracted positions may correspond respectively to the stowed and towing positions of the tow hitch member. The tow hitch arrangement may be configured to move the latch arm from the extended position to the retracted position as the tow hitch member is moved from the towing position to the stowed position. The latch assembly may comprise a latch arm release mechanism configured to release and / or move the latch arm from the extended position towards the retracted position to allow the tow hitch member to be raised. The latch arm release mechanism may be provided in the operator structure. The latch arm may comprise an engagement feature configured to contact a running surface of the tow hitch member. The running surface may be provided in an upwards facing surface of the tow hitch member and be configured to engage with and guide the latch arms into the retracted position when moving the tow hitch member from the towing position to the stowed position. Guiding the tow hitch member from the towing position to the stowed position may comprise the engagement feature to slide along the running surface thereby moving the latch arm into the retracted position. The engagement feature may be any suitable surface of the latch arm which is configured to engage with the running surface of the tow hitch member. The latch arm may be a plate-like member having a length, a depth and a width. The major plane may be defined by the length and width of the plate-like member and may be aligned with the principal axis of the machine. The width of the latch arm may comprise an edge surface on an underside thereof when the latch arm is in an extended, or when moved towards the or in the retracted position. The tow hitch may comprise a hook for receiving a trailer hitch of the trailer to be towed. The hook may be provided below and proximate to a closing plate positioned to prevent removal of the trailer hitch when in the towing position. The closing plate may be configured to move between an extended position and a retracted position. The may extended and retracted positions correspond respectively to the stowed and towing positions of the tow hitch member and / or the latch arm member. The latch arm may comprise the closing plate such that the latch arm and closing plate concurrently move between the extended and retracted positions. The tow hitch member may be moved towards the closing plate when moving from the lowermost loading position to the towing position. The closing plate may reside proximate an upper surface of the tow hitch member, thereby limiting and / or blocking upwards movement of the tow hitch member from the towing position. The working vehicle may further comprise a stowed position retention mechanism configured to engage with the tow hitch member when in the stowed position and to prevent unintentional lowering of the tow hitch member. The stowed position retention mechanism may be configured to be disengaged by an operator prior to lowering the tow hitch member. The stowed position retention mechanism and latch arm release mechanism may be actuable from the operator structure using a common release input device. The release input device may comprise a pivotable lever mounted in the operator structure and positioned to be operable by an operator from an operator seat. The present disclosure provides a method of deploying a tow hitch in a working machine. The method may comprise: lowering the tow hitch from a stowed position through a towing position to a loading position using an actuation arrangement; attaching a trailed unit to the tow hitch; raising the tow hitch to the towing position using the trailed arrangement. Moving the tow hitch member from the towing position to the stowed position may comprise: releasing a latch arrangement; operating the actuation arrangement to lower the tow hitch member to a predetermined position; and, subsequently raising the tow hitch member to the stowed position. The latch arrangement may provide a mechanical restraint to prevent unintentional movement of the tow hitch member when in first latched position and allow movement using the actuation arrangement when in a second position. Releasing the latch arrangement may comprise an operator operating a latch release input device, such as a lever, in an operator structure of the working machine. Lowering the tow hitch member from a stowed position may comprise releasing a stowed position retention mechanism from the tow hitch member prior to commencing lowering. Raising the tow hitch member from a towing position to a stowed position may comprise moving a mechanical stop which resides above the tow hitch member and blocks upwards movement thereof when engaged. The skilled person will appreciate that except where mutually exclusive, a feature described in relation to any one of the aspects, embodiments or examples described herein may be applied mutatis mutandis to any other aspect, embodiment or example. Furthermore, except where mutually exclusive, any feature described herein may be applied to any aspect and / or combined with any other feature described herein. BRIEF DESCRIPTION OF DRAWINGS Embodiments will now be described by way of example only with reference to the accompanying figures, in which: Figure 1 shows a working vehicle having a tow hitch arrangement according to the present disclosure; Figure 2a shows the tow hitch arrangement in a stowed position; Figure 2b shows the tow hitch arrangement in a towing position; Figure 2c shows the tow hitch arrangement in an extended loading position; Figures 3a to 3c correspond to Figures 2a-2c respectively with the inclusion of body panels of the working machine; Figure 4 shows a tow hitch system including the tow hitch arrangement and operator release lever; Figure 5 shows a side view of the tow hitch arrangement and a latch assembly for vertically restraining the tow hitch; Figure 6 shows a perspective view of the latch assembly; Figures 7a, 7b and 7c show the initial stages for moving a latch arm from a deployed position towards a retracted position using a runner surface of the tow hitch member; Figures 8a and 8b show the constructional details of a latch arm release mechanism; Figure 9 shows a top down view of the tow hitch arrangement; Figure 10 shows a perspective view of the tow hitch in the loading position to further aid understanding; Figures 11 and 12 show the tow hitch arrangement in the stowed position from above and below to further aid understanding. DETAILED DESCRIPTION In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of various embodiments and the inventive concept. However, those skilled in the art will understand that: the present invention may be practiced without these specific details or with known equivalents of these specific details; that the present invention is not limited to the described embodiments; and, that the present invention may be practiced in a variety of alternative embodiments. It will also be appreciated that well known methods, procedures, components, and systems may have not been described in detail. The same reference numerals may be used for corresponding features throughout the drawings. In such cases, the description of these features may not be repeated. Referring firstly to Figure 1, the present disclosure provides a working machine 1 which may be a material handling machine in the form of wheeled loading shovel. In alternative embodiments, the working machine 1 may be a telescopic handler, for example, or some other form of working machine which may benefit from the retractable tow hitch of the present disclosure. The working machine 1 of the illustrated embodiment includes a body 2 which comprises an articulating chassis and an operator structure 3, for example, an enclosed operator cab from which an operator can operate the machine 1. In other embodiments, the working machine 1 may have an open canopy structure (not shown) for the operator. In the illustrated embodiment, the working machine 1 has a ground engaging propulsion structure 4, 5 comprising a first axle and a second axle, each axle being coupled to a pair of wheels (two wheels 4, 5 are shown in Figure 1 with one wheel 4 connected to the first axle and one wheel 5 connected to the second axle). The first axle may be a front axle and the second axle may be a rear axle in accordance with the principal direction of travel. One or both of the axles may be coupled to a prime mover 12, e.g. an internal combustion engine, which is configured to provide tractive effort to drive movement of one or both pairs of wheels 4, 5 via a transmission. Thus, the wheels 4, 5 may contact a ground surface and rotation of the wheels 4, 5 may cause movement of the working machine 1 with respect to the ground surface. In other embodiments, the ground engaging propulsion 4, 5 structure may comprise tracks or rollers. In some embodiments, the transmission may comprise a hydraulic pump which is driveably coupled to the prime mover 12 and which provides traction via one or more hydraulic motors. Alternatively, the prime mover 12 may comprise an electric motor for providing traction to the wheels 4,5 or tracks. In some embodiments the powertrain of the vehicle may comprise an electrical drive line and / or hybrid configuration. The engine may be an internal combustion engine, for example, a gaseous fuel engine, such as hydrogen, or a diesel. In yet further embodiments, the power train may comprise a fuel cell as well known in the art. Other examples of prime mover or power train may be suitable. A material handling apparatus is coupled to the machine body 2. The material handling apparatus includes a working arm 6 mounted to the front of the machine body 2. A working implement 8, in this case a fork arrangement, is mounted to an end of the working arm 6. In alternative embodiments, the working implement 8 may be any suitable attachment, such as a shovel, grab or buckrake etc, as well known in the art. The working arm 6 raises and lowers the working implement 8 using a suitable actuator such as a hydraulic or electrical ram. The body 2 may comprise various body panels 9 for aesthetic purposes and to shield the inner components of the working machine 1 from the outside environment. In the illustrated example, the working machine 1 comprises a rear body portion 10, aft of the rear wheels 5, which may include an underside comprising an upwardly angled portion which rises towards the rear of the working machine 1. The upwardly angled portion provides the working machine 1 with added ground clearance at the rear to allow it to transition onto relatively steeply inclined portions of ground whilst avoiding contact between the rear body portion 10 and ground surface. This may be particularly important when employed, for example, in a quarry where access ramps can be relatively steep, or in agriculture, for example, when constructing a clamp where the relative angle between the ground contacted by the wheels and trailing ground can transition relatively sharply over a short distance. The upwardly angled portion of the rear body portion 10 may be planar, curved or include multiple facets when viewed from the side. However, the departure angle of the working machine 1 may be usefully defined by a plane 11 which extends between the ground contact point of the rear wheels 5 and the rearmost contact point of the underside of the rear body portion 10 which limits the ground clearance in relation to the trailing ground when travelling forwards. The departure angle 11 of the vehicle in Figure 1 is shown by the dashed line 11 and extends from the ground contact point of the rear wheels 5 towards the back corner of the working machine 1. A typical departure angle for a wheeled loading shovel may be between 20 and 30 degrees, preferably approximately 25 degrees. As will be appreciated, the departure angle 11 of a working machine 1 will be dependent on the type and size of working machine in question, and the particular purpose / application of that machine so other angles may be applicable. The upwardly angled portion of the rear body portion 10 is shown as including a tow hitch arrangement 20 to which a trailed unit, e.g. a transport trailer or trailed implement (not shown), may be attached for transportation. The type of trailed unit may be any known in the art. An issue with tow hitches on working machines 1 having an upwardly angled portion, such as that shown in Figure 1, is that the tow hitch arrangement 20 either: 1) protrudes from the underside of the machine 1 which reduces the effective departure angle of the vehicle (as shown by dashed line 11'), or 2) has to be placed on an aft wall of the working machine 1 which can result in towing position being undesirably high for many applications. A further issue with providing tow hitches on the underside of a working machine is that they can be more troublesome for an operator to couple a trailer to the machine when towing is required. The example provided in EP3257689 suffers by requiring multiple manual operations to deploy and stow. The present disclosure seeks to address some of these issues by providing a tow hitch arrangement 20 comprising a tow hitch member 21 mounted to the rear body portion 10 at a first end and comprising a tow hitch 23 at a second end. The tow hitch member 21 is movable, e.g pivotable, between a stowed position in which the tow hitch is housed within the rear body portion 10 (Figure 2a), that is, substantially inside the upwardly angled portion of the rear body portion 10, and a towing position (Figure 2b) in which the tow hitch 23 projects down from the rear body portion 10 and is configured to retain a corresponding tow hitch attachment of a trailed unit to be towed. In some embodiments, the tow hitch member 21 may also be movable to an open / loading position (Figure 2c) in which the tow hitch 23 is lowermost and suitable for receiving the tow hitch attachment 31 of the trailed unit to be towed, prior to being raised into the towing position. With reference to Figures 2a to 2c, there is shown a tow hitch arrangement 20 in which the tow hitch member 21 is shown in stowed, towing and loading positions respectively. Figure 2a shows the tow hitch member 21 in a stowed position in which the tow hitch 23 is housed within an internal cavity of the rear body portion 10. The cavity may be defined by structural members of the chassis 19 and / or other components such as a fuel tank or hydraulic tank (not shown) which may be provided alongside the tow hitch arrangement 20. Figure 2b shows the tow hitch 23 in a towing position in which a corresponding tow hitch attachment 31 of a trailed unit may be safely attached for towing. Figure 2c shows the tow hitch member 21 in a fully deployed / extended state so that a corresponding trailer tow hitch attachment 31 can be loaded on to tow hitch 23 prior to raising the tow hitch member 23 into the towing position. Figures 3a to 3c show the same tow hitch arrangement 20 positions corresponding to 2a-c but with the body panels 24 of the rear body portion 10 shown. As can be seen from Figure 3a, when in the stowed position, the tow hitch member 21 is housed above the line of the rear body portion 10 which defines departure angle 11 of working machine 1 within an internal cavity of the rear body portion 10. In the illustrated embodiment, the underside of the tow hitch member 21 extends slightly below the level of the side body panels 24 to provide some protection of the body panels 24 or surrounding elements such as fuel or hydraulic tanks of the working vehicle 1 in the event of a ground contact. That is, leaving the tow hitch member 21 slightly proud of the underside of the rear body portion 10 provides a structurally resilient member for contacting the ground when the departure angle of the machine 1 is exceeded, thereby helping to reduce the potential for damage to less robust parts of the machine. In other embodiments, the tow hitch member 21 may be fully concealed within the rear body portion 10. As can also be seen in Figures 3b and 3c, a latch arm 28 and a closing plate 30 of the tow hitch arrangement 20 also extend below the rear body portion 10 when the tow hitch member 21 is lowered. These are described in further detail below. As best seen in Figures 2b, and 2c, 9 and 10, the tow hitch member 21 is elongate and lies fore-aft in relation to the working machine 1 so as to be longitudinally aligned with the principal direction of straight line travel, i.e. the principal fore-aft axis of the machine 1. A first end of the tow hitch member 21 comprises the pivot mount 22 allowing the tow hitch member 21 to be rotatably moved between the different positions. The second end of the tow hitch member 21 comprises a tow hitch 23. The terminal end of the tow hitch 23 is located towards the extreme rear of the working machine 1 and may be approximately coterminous with the rear panel 25 of the rear body portion 10 of the working machine 1 (see Figures 1 and 3a) to allow for easy connection to a trailed unit and prevent fouling between the trailed unit and rear body portion 10 when being towed. The tow hitch 23 may be any suitable type, such as ball hitch or a pintle hitch. In the illustrated embodiment, the tow hitch 23 is a pintle style hitch comprising a hook 23-1 for receiving a corresponding pintle ring (which may be referred to as a drawbar eye or lunette ring) of a trailed unit attachment 31, and a closing plate 30 (which may be referred to as a keep). The closing plate 30 and hook 23-1 define between them a substantially closed loop in which a pintle ring may be received and prevented from detached during towing. The closing plate 30 is held in a fixed relation to the tow hitch body 27 when in the towing position but may be retracted into the rear body portion 10 when the hitch is in the stowed position. This is described in more detail below. In some embodiments, the closing plate 30 may be appended to the tow hitch member 21. In order to effect actuation of the tow hitch member 21 between the stowed, towing and loading positions, the tow hitch arrangement 20 is provided with an actuation arrangement 34 (principally identified in Figure 2a and shown throughout). The actuation arrangement 34 may comprise any suitable actuator for effecting the movement of the tow hitch member 21 between the described positions. In the illustrated embodiment, there is provided a hydraulic actuator arrangement 34 comprising a pair of conventional hydraulic cylinders 36a,b (see Figure 4) which are longitudinally disposed on either side of the tow hitch member 21. The cylinders 36a,b are configured to operate in unison to raise and lower the tow hitch member 21 between the various positions. It will be appreciated that some embodiments may comprise a single hydraulic cylinder or alternative conventional actuator types including, for example, pneumatic or electrical actuators, linear or rotary actuators. The cylinders 36a,b extend between respective lever arms 37a,b of the tow hitch member 21 and the chassis 19 such that extending the cylinders raises the tow hitch member 21, and retracting the cylinders lowers the tow hitch member 21 between the stowed, towing and loading positions. Each hydraulic cylinder 36a,b comprises a capped cylindrical body having a rod end and a full bore end. A piston is slidably received within the cylindrical body and attached to the rod to define a full bore chamber and a rod end chamber. Controlling the flow of pressurised hydraulic fluid in and out of the full bore and rod end chambers causes extension or retraction of the rod, as well known in the art. In the illustrated embodiment, the rod end of the cylinders 36a,b are pivotably attached to the first, pivoting end of the tow hitch member 21 via the respective lever arms 37a,b which extend upwardly from the tow hitch member 21 into the interior of the rear body portion 10. The bore end of the cylinders 36a,b are pivotably attached to a second part 27b of the body 27. The attachment of the bore end of the cylinder housing and rod end may be achieved using any known pivoting connection, with the illustrated embodiment comprising conventional clevis joints. As can be seen by the respective lengths of the exposed rod in Figures 2a-c, extending the length of the cylinder causes an upwards rotation of the tow hitch member 21 and raising of the tow hitch 23. Retracting the cylinder causes a downwards rotation and lowering of the tow hitch 23. It will be appreciated that the number and size of the hydraulic cylinders and the relative positions of the mounting points and length and position of the lever arm may be application specific and adjusted to meet different operating requirements. However, arranging the cylinders 36a,b such that the extension is utilised to lift the tow hitch 23 and any attached load between the lowermost loading position and towing positions is advantageous due to the increased force which can be achieved during extension. The operation of the actuation arrangement 34 may be carried out remotely by an operator of the machine, for example, from the operator structure 3 or by a controller mounted local to the rear of the working machine 1. Thus, the working machine 1 may be provided with a suitable push buttons or other control devices mounted on an operator console or control member such as a joystick, or on a machine display unit, for example, to allow the tow hitch member 21 to be moved between the different positions. Alternatively or additionally, the working machine 1 may comprise a control device at the rear of the vehicle which comprises the necessary controls such as a raise and lower the tow hitch member 21. In order to prevent unintended movement of the tow hitch member 21, the tow hitch arrangement 20 may comprise one or more mechanical restraints configured to prevent the tow hitch member 21 unintentional movement, either in the event of a loss of hydraulic pressure to the actuator arrangement 36 or by accidentally operating the actuation arrangement 34 when not intended or required 34. A first mechanical restraint may be effective when the tow hitch member 21 is in the towing position. A second mechanical restraint may be arranged to prevent the tow hitch member 21 from being raised when in the towing position to prevent accidental raising when a trailed unit is attached to the tow hitch 23. A third mechanical restraint may be provided to prevent the tow hitch member 21 being deployed from the stowed position unintentionally. Some embodiments may include only one of the first, second and third mechanical restraints. In embodiments with two or more of the mechanical restraints, they may share some common components so that, for example, the requirements of the first and second mechanical restraints are achieved using a common mechanical arrangement of parts. The first mechanical restraint of the illustrated embodiment is best seen in Figures 2c, 4, 5 and 6. Figure 2c is described above and shows a side view of the tow hitch member 21 in a loading position and a latch arm 28 and closing plate 30 extending downwardly from the rear body portion 10. Figure 4 shows a perspective view of the hitch arrangement 20 inboard the machine 1 and an operator release lever 50 which is connected to a latch assembly 54 of the tow hitch arrangement 20 shown in Figures 5 and 6. The operator release lever 50 is operable to release or remove one or more of the mechanical restraints to allow the tow hitch member 21 to be moved between the two or more of the positions. The release lever 50 can take any suitable form such as pivoting handle which graspable and operable by an operator from the operator seat in the operator structure 3. In some embodiments, the release lever 50 may be operable to disengage any or all of the first, second and third mechanical restraints. Hence, the operator release lever 50 may have multiple functions which are each effected by a sequence of separate operations or by placing the lever in different relative positions. For example, in some embodiments, the lever 50 may be movable from a neutral position to a first release position to enable to disengage the first mechanical restraint, from the first release position to a second release position to disengage the second mechanical restraint, or from the neutral position to the first and second release positions. In some embodiments, the release lever 50 may comprise multiple separate levers for carrying out different release functions. For example, there may be a first lever for disengaging the first mechanical restraint, and a second lever for disengaging the second mechanical restraint. The operator release lever 50 of the illustrated embodiment may be operably connected to a respective mechanical restraint in the hitch arrangement 20 by a suitable mechanical link such as a cable 52 which can be tensioned or slackened by the lever 50 to effect operation. In the embodiment of Figure 4, the lever 50 is connected by a pair of cables 52 within an outer sheath 51 with a first one of the cables going to the first mechanical restraint and the second cable 53 going to the second mechanical restraint. In the illustrated embodiment, the second cable is also operable to release a third mechanical restraint using a common actuation system. It will be appreciated that in some embodiments, the function achieved by the operator release lever 50, may be implemented in software with a virtual control provided on a touch screen display, or the required release functions may form part of an automated sequence carried out when instigating a movement of the hitch member 21. Figures 5 and 6 show a side and perspective views respectively of the hitch arrangement 20 and the latch assembly 54 which provides the first mechanical restraint and prevents unintentional release of the tow hitch member 21 from the towing position. The latch assembly is movable between a first position in which the tow hitch member is restrained to prevent lowering using the actuation arrangement (or otherwise) and a second position in which the tow hitch member may be lowered by the actuation arrangement (or otherwise). The latch assembly 54 comprises inter-engaging parts which prevent accident release or operation of the tow hitch member 21. The latch assembly 54 of the illustrated embodiment comprises a first member and a second member which are attached to the body of the tow hitch arrangement 20 (or chassis 19) and tow hitch member 21 respectively. The first member may comprise the one or more latch arms 28 which extend(s) downwardly from the underside of the rear body portion 10 to engage with the second member which is provided in the form of a latch member 40 mounted to the tow hitch member 21. The engagement between the latch arm 28 and latch member 40 is operably releasable such that the latch assembly 54 may be engaged when the tow hitch member 21 is in the towing position but releasable upon command to allow the tow hitch member 21 to be lowered and / or stowed. With additional reference to Figure 10, the illustrated embodiment is provided a pair of latch arms 28 placed on either side of the tow hitch member 21 towards the second end and tow hitch 23. The latch arms 28 may be located proximate to and aligned with the respective the tow hitch member 21 so as to be adjacent to the latch member 40. The latch arms 28 may be pivotably attached to the tow hitch arrangement body 27 and / or chassis 19 such that they are to rotatable between the stowed and deployed, latching positions. The tow hitch member 21 in the illustrated embodiment is of a substantial construction having a body with a width W, length L and depth D (see Figure 10) in which the length is greater than the width which is greater than the depth. However, the absolute and relative dimensions of the tow hitch member 21 may vary and be application specific. With reference to Figures 11 and 12, the tow hitch member 21 maycomprisea box section construction having lateral walls 21s between which upper 21u and lower 211 walls extend fully or partially. The second end may comprise a pair of arms 21-1, 21-2 between which the tow hitch 23 is secured, thereby providing the necessary strength and rigidity required for in-service loads. One or more cross members 21-3 may be provided to laterally restrain the arms 21-1, 21-2 and provide additional structural rigidity. The pivot mount 22 extends the full width of the tow hitch member 21 and comprise a tubular body 26-1 which rotatably receives a pin 26 which is supported at either end by the hitch arrangement body 27 and defines the rotational axis of the tow hitch member 21. Each of the arms 21-1 and 21-2 may comprise respective box sections having internal side plates located opposite the external lateral walls 21s and defining a cavity therebetween. The cavity may comprise the latch assembly 54 and receive the latch arms 28 when the tow hitch member 21 is in the towing position, as seen in the partial cross-sectional views shown in Figures 5 and 6. In the illustrated embodiment, the cross member 21-3 is provided in the form of a plate which extends between the arms 21-1, 21-2 and connects to a body portion of the hitch member 23. As described above, the cross-member 21-3 may be comprise one or more surfaces which provide one or more of the mechanical restraints preventing unintentional movement of the tow hitch member 21. Thus, there is provided a central portion having an upper surface 21-4 to contact the underside of the closing plate 30 thereby preventing upwards movement from the towing position; a laterally disposed upper surface 21-5 configured to contact a landing surface 63 on an underside of the latch arm lever 57 to allow rotation of the latter and upwards movement of the tow hitch member 21; and, an underside surface 21-6 which provides a bearing surface for preventing lowering of the tow hitch member 21 when received within the notch 61 of the latch arm lever 57. The location of the restraint features on the cross-member 21-3 is convenient, however, it will be appreciated that the various surfaces may be provided elsewhere on the tow hitch member 23. In the illustrated embodiment, the latch arm 28 comprises an elongate plate-like construction in which the plane of the plate-like body is aligned with the principal axis of the machine 1 providing forward and rearward facing side surfaces with the engagement feature provided in the form of a recess 43, for example a notch or groove, in a forward edge thereof. The recess 43 is configured to receive the latch member 40 in such a way that once in place, downward movement tow hitch member 21 is prevented. In the illustrated embodiment, the recess 43 comprises an angled upward facing bearing surface 43' which is configured to receive the rotatable latch member 40. The bearing surface 43' may be angled so as to allow the latch member 40 to be rotatably inserted into and retracted out of the recess, whilst providing a vertical engagement sufficient to prevent vertical movement of the tow hitch member 21. The latch member 40 comprises a rotatable body 41 which is mounted to the tow hitch member 28 via a pivot mount 42 and includes a lever arm 44 for rotating the body 41 to release the latch member from the recess 43. A latch member arm 46 extends radially from the latch member body 41 and is received within the recess 43 when in the engaged position, and moved out of the recess 43 to allow the tow hitch member 21 to move downwards. As will be appreciated, downwards movement of the tow hitch member 21 when the latch member 40 is engaged is prevented by the terminal end of the latch member arm 46 contacting the opposing bearing surface 43' of the recess 43. It will be appreciated that the bearing surface which receives the latching member 40 may be provided by any appropriately orientated surface on the latch arm 28 and may be included on a projection or other form of cut-out that the recess 43 shown in the illustrated embodiment. The latch member 40 may further comprise a biasing element 47, shown as a helical compression spring in the illustrated embodiment, which biases the latch member 40 into the engaged position. The bias enables automatic rotation of body 41 and engagement of the latch member arm 46 as the tow hitch member 28 is raised, as described below. Actuation of the latch member 40 to release the tow hitch member 21 for downwards movement may be achieved in any desirable way. For example, the lever arm 44 which causes the body 41 to rotate may be driven by a mechanical connection or an electrical solenoid, or may be hydraulically or pneumatically operated. The actuation of the latch member 40 may be controlled from the operator structure 3 using a suitable input device such as, for example, a rotary or toggle switch, or a virtual switch provided on a touch screen or the like. In the illustrated embodiment of Figure 4, the actuation of the lever arm 44 is achieved using the mechanically linked operator release lever 50 provided in the operator structure 3. The release lever 50 is connected to the lever arm 44 via cable 52, and configured to pull or release the cable 52 with a corresponding movement of the handle. Thus, pivoting handle 50 up pulls the cable 52 to release the latch member 40, whilst moving the handle down slackens the cable 52 allowing the latch body 41 to rotate into the engaged position under the influence of the biasing member 47. The illustrated embodiment further comprises a pair of rigid links 48, each extending longitudinally forwards from the lever arms 44 on respective sides of the tow hitch member 21 and connected to each other by cross member 49. The cable 52 extends from a central connecting point of the cross member 49 such that exerting a force on the cable 52 using lever 50 causes both latch member bodies 41 to rotate. In use, to release the hitch member 21 from the towing position shown in Figures 2b, 5 and 6, the operator pulls lever 50 upwards to tension cable 52 and pull the cross member 49 (to the right as shown). This pulls the respective lever arm 44 which in turn causes rotation of the body 41 and withdrawal of lever member arm 46 from the recess 43 in the respective latch arm 28. When the lever member arm 46 is clear of the recess 43, the tow hitch member 21 is rotatable to lower the tow hitch member 21 using actuation arrangement 34 upon command. Once the tow hitch member has been lowered to a point where the terminal end of the lever member arm 46 is below recess 43, which occurs almost immediately following the downwards movement of the tow hitch member 21, the actuating force on the latch member 40 can be released by the lever 50 resulting in the biasing member 47 urging the latch member arm 46 towards the side of the latch arm 28 but without hindering the downwards movement. When the hitch member 21 is moved from the loading position to the towing position, the latch member arm 46 contacts the curved landing surface 55 on the underside of the latch arm 28 thereby rotating the body 41 until the tow hitch 21 is in the towing position and the latch member arm 46 is moved into the recess 43 under the influence of the biasing member 47. In order to prevent unintentional upwards movement of the tow hitch member 21 into the stowed position, for example when a trailed unit is connected, the tow hitch arrangement 20 may comprise a second mechanical restraint in the form of a mechanical stop which abuts a corresponding part of the tow hitch member 21. The stop may have a deployed position in which upwards movement from the towing position of the tow hitch member 21 is prevented, and a retracted position in which the tow hitch member 21 may be moved upwards into the stowed position. As best seen in Figures 2b, 2c and 10, in the illustrated embodiment, the stop is provided by the closing plate 30 which resides above the tow hitch 23 when in the towing position. The closing plate 30 is positioned above the cross member 21-3 which comprises a stop surface 21-4 which opposes an underside of the closing plate 30 and prevents upwards movement in the event that the tow hitch member 21 is actuated upwards unintentionally. Retraction of the latch arms In order to allow the tow hitch 21 to be raised from the towing position to the stowed position, the closing plate 30 may be retractable. In the illustrated embodiment, the closing plate 30 is attached to the latch arms 28 such that retracting the latch arms 28 also retracts the closing plate 30 to allow the tow hitch member 21 to be stowed. With reference to Figures 6, 7a-c and 11, the latch arms 28 are configured to be movable between a deployed position and a retracted position. In the deployed position, the latch arms 28 extend downwards so as to engage with the latch member 40, as previously described, with the closing plate 30 located above the tow hitch 23 and cross member 21-3. In the retracted position, the latch arms 28 may be stored within the internal cavity on the rear body portion 10, as best seen in Figure 11. In order to transition the latch arms 28 between deployed and retracted positions, the latch arms 28 may be rotatably mounted to the hitch body 27b and pivoted into the retracted position prior to or as the tow hitch member 28 is lifted into the cavity. In the illustrated embodiment, the movement of the latch arms 28 is initiated by the operator, for example, by using lever 50, to allow them to be engaged by the tow hitch member 21 as it is being raised from below the towing position. Figure 7a shows the tow hitch member 21 in a position in which latch members 40 have been disengaged from the latch arms 28 (as previously described) and the tow hitch member 21 has been lowered to a position where it is fully separated from the latch arms 28. The latch arms 28 may then be rotated forwards by a suitable actuation arrangement, such as lever 50, so that an underside of the latch arm 28 is presented above a runner 56 on the top side of the tow hitch member 21 in an intersecting path (Figure 7b). Following this, the tow hitch member 21 is raised using the actuation arrangement until the runner 56 and underside of the latch arms 28 contact (Figure 7c). Continued raising of the tow hitch member 21 results in the rotation of the latch arms 28 as the distal end travels along the runner surface until the latch arms 28 are located in the fully retracted position shown in Figure 11. Thus, the latch arms 28 are movable from a deployed position to retracted position via intermediate position in which the latch arms 28 are presented above the runners 56. As can be seen in Figures 10 and 11 the runners 56 may extend along the full length of upper surface of the tow hitch member 21 and comprise a suitably curved profile to effect rotation of the latch arms 28 from the initiated position shown in Figure 2b to a fully stowed position in which they lie horizontal and extending forwards into the body above the tow hitch member 21. The initial forward movement of the latch arms 28 from the deployed position to the intermediate position may be achieved using one or more electrical, hydraulical or pneumatic actuators. The forward movement of the latch arms 28 may be controlled from the operator structure 3 using a suitable input device such as, for example, a rotary or toggle switch, or a virtual switch provided on a touch screen or the like. In the illustrated embodiment, the initial actuation of the latch arms 28 to the intermediate position is achieved using lever 50 in the operator structure 3 which effects sufficient rotation to put the latch arms 28 above the runners 56 using cable 53. It will be appreciated that in embodiments where the closing plate 30 is attached to the latch arms 28, raising the latch arms 28 results in the closing plate 30 moving upwards and being stowed in the rear body portion 10. Thus, the removal of the second mechanical restraint which prevents unintentional movement of the tow hitch member 21 from the stowed position is retractable with latch arms 28. In order to provide the initial movement of the latch arms 28, with reference to Figures 8a and 8b, there is provided a latch arm release mechanism in the form of lever 57 which is actuatable to rotate the latch arms 28 about the pivot pin 29 between the latch position and the intermediate position which allows the tow hitch member 21 to be raised as shown in Figure 7b. The latch arm lever 57 is pivotably mounted on a common pivot axis with the latch arms 28 and connects to the latch arms 28 via a connecting member 58 which extends laterally between the terminal ends of the latch arms 28 provided on either side of the tow hitch member 21. There are a pair of latch arm levers 57 connected by a lateral brace 65, such that the actuating cable 53 need only connect to one of the latch arm lever 57 Rotating the latch arm lever 57 (as shown by the arrow) rotates the connecting member 58 which in turn rotates the latch arms 28 forward as shown in Figure 7b. The actuation of the latch arm lever 57 and latch arms 28 is achieved via a link member in the form of a cable 53 which attaches to the lever 50 via the outer sheath 51 and is movable by an operator in the operator structure 3. The tow hitch arrangement 20 may comprise a stowed keep configured to engage with the tow hitch member when in the stowed position and to prevent unintentional lowering of the tow hitch member. The stowed keep may be configured to be disengaged by an operator, for example, using an operator release lever 50 as described above. In the illustrated embodiment, the stowed keep comprises the latch arm lever 57. Thus, the latch arm lever 57 provides a dual purpose in that it causes the rotation of the latch arms 28 and also latches the tow hitch member 21 in the stowed position so that the tow hitch member 28 cannot be unintentionally be lowered without the operator activating latch arm release. In some embodiments, the function of the lever arm 57 may be achieved by connecting cable 53 directly to the latch arms 28 to provide the initial movement, rather than having a separate lever arm 57 and connecting member 58. However, in the illustrated embodiment, the latch arm lever 57 comprises a third mechanical restraint in the form of a retention feature for retaining the tow hitch member 21 when in the stowed position. The retention feature in the keep may comprise a notch 61 which receives the a portion of the cross member 21-3 of the tow hitch member 21 when in the stowed position. The cross member 21-3 may comprise a contacting surface 21-6 which opposes a corresponding upward facing surface 62 of the notch 61. In order to provide the dual functionality, the latch arm lever 57 is independently rotatable from the latch arms 28 and comprises a biasing member 65 which is attached to the latch arm lever 57 (via the lateral brace 65 in the illustrated embodiment) and configured to return to the latch arm lever 57 to the neutral vertical position when the release lever 50 is not actuated in the operator structure 3. As such, following the initial movement of the latch arm 28 to allow the tow hitch member 21 to be raised, the latch arm lever 57 may be released to return to the originating position shown in Figure 8b, thereby allowing the cross-member 21-3 to be received within the notch 61 as described above. The underside of the latch arm lever 57 includes a landing surface 63 which is angled such that contact with an opposing upward facing surface 21-5 of the cross-member 21-3 as the tow hitch member 21 ascends, displaces the latch arm lever 57 to allow continued upwards motion of the tow hitch member 21. When the tow hitch member 21 approaches the stowed position, the cross-member 21-3 is level with the notch 61 allowing the biasing member 64 to urge the latch arm lever 57 into the original position thereby receiving the cross-member 21-3 and placing the bearing surface 62 and underside of the cross-member in an opposing relation. Operating the latch arm lever 57 using the operator release lever 50, as described previously, rotates the latch arm lever 57 such that the cross-member is no longer in the notch 61 and the tow hitch member 21 can be lowered using the actuation arrangement 34. It will be appreciated that the functions provided by latch arm lever 57 which actuates the movement of the latch arms 28 and provides the third mechanical restraint may be achieved using separate actuation mechanisms. Hence, in some embodiments, the latch arm lever 57 may only rotate the latch arms 28 with the third mechanical restraint may be provided by a separately actuable member. However, providing the dual functionality with a common component as described allows the release lever 50 to be used for both stowing the tow hitch member 21 (by moving the latch arms 28), and also for releasing the tow hitch member 21 by disengaging the third mechanical restraint. Actuation of the first mechanical restraint (which allows the latch member 40 to be disengaged to allow the tow hitch member 21 to be lowered from the towing position) may be provided by a separate lever 50, or a different position for the lever 50, to help differentiate this operation for an operator. The pivot mount 22 comprises an elongate pin 26 which extends laterally across the working machine 1 and defines the pivot axis 22-1 for the hitch member 21. The tow hitch member 21 in the illustrated embodiment is of a substantial construction having a body with a width W, length L and depth D (see Figure 10) in which the length is greater than the width which is greater than the depth. However, the absolute and relative dimensions of the tow hitch member 21 may vary and be application specific. With reference to Figures 11 and 12, the tow hitch member 21 may comprise a box section construction having lateral walls 21s between which upper 21u and lower 211 walls extend fully or partially. The second end may comprise a pair of arms 21-1, 21-2 between which the tow hitch 23 is secured, thereby providing the necessary strength and rigidity required for in-service loads. One or more cross members 21-3 may be provided to laterally restrain the arms 21-1, 21-2 and provide additional structural rigidity. The pivot mount 22 extends the full width of the tow hitch member 21 and comprise a tubular body 26-1 which rotatably receives a pin 26 which is supported at either end by the hitch arrangement body 27 and defines the rotational axis of the tow hitch member 21. In the illustrated embodiment, the cross member 21-3 is provided in the form of a plate which extends between the arms 21-1, 21-2 and connects to a body portion of the hitch member 23. As described above, the cross-member 21-3 may be comprise one or more surfaces which provide one or more of the mechanical restraints preventing unintentional movement of the tow hitch member 21. Thus, there is provided a central portion having an upper surface 21-4 to contact the underside of the closing plate 30 thereby preventing upwards movement from the towing position; a laterally disposed upper surface 21-5 configured to contact a landing surface 63 on an underside of the latch arm lever 57 to allow rotation of the latter and upwards movement of the tow hitch member 21; and, an underside surface 21-6 which provides a bearing surface for preventing lowering of the tow hitch member 21 when received within the notch 61 of the latch arm lever 57. The location of the restraint features on the cross-member 21-3 is convenient, however, it will be appreciated that the various surfaces may be provided elsewhere on the tow hitch member 23. With reference to Figures 2a-2c, 4 and 9 to 12, the tow hitch arrangement 20 comprises a hitch arrangement body 27 which provides structural support for the working parts of the tow hitch arrangement 20 and defines a cavity within which the tow hitch member 21 and tow hitch 23 can reside when in the stowed position. The body 27 may comprise multiple parts which are separately mounted to the chassis 19 of the vehicle, or a unitary structure. In the illustrated embodiment, the body 27 comprises a first part 27a at the first end of the tow hitch arrangement 20 and a second part 27b provided at a second end of the tow hitch arrangement 20. The first part 27a and second part 27b are separate structural components individually attached to the vehicle chassis 19 at suitable mounting points. Thus each of the of the first 27a and second 27b parts of the body 27 comprise mounting plates which are attached to the chassis 19 using suitable fixings, such as threaded bolts or studs and nuts 27c. See also bolt holes 27' in side plates as identified in Figure 4). Other means of fixing, such as welding are well known. The first 27a and second 27b parts are held in a stationary relation via the connection with the chassis 19 but may be directly connected by one or more interconnecting members where appropriate (not shown). The following describes the deployment of the tow hitch 23 from the stowed position to the loading position, from the loading position to the towing position, from the towing position back to the stowed position. When the tow hitch is required, an operator first operates the release lever 50 from within the operator structure to release the tow hitch member from the third mechanical restrain. Thus, in the illustrated embodiment, the latch arm lever 57 is pivoted forwards such that the cross-member 21-3 is released from the notch 61 thereby opening the path for the tow hitch 23 to be lowered. Whilst maintaining the release position on the lever 50, the operator operates the control for lowering the tow hitch, for example, by activating a "lower tow hitch" input device on an operator console. This causes the hydraulic cylinders 36a and 36b to retract and the tow hitch member 21 to pivot down. The downward movement of the tow hitch member 21 allows the latch arms 28 and closing plate 30 to fall under gravity along the tow hitch member runners 56 until fully extended in the vertical deployed position. The downward movement of the tow hitch member 21 continues until full retraction of the cylinders 36a,b is achieved, at which point the tow hitch 23 is in the lowermost position and ready to receive the hitch 31 from the trailed unit. Once the trailed unit hitch 31 is located over the tow hitch 23, the operator activates a "raise tow hitch" input device on the operator console which causes cylinders 36a,b to extend against lever arms 37a,b, thereby raising the tow hitch 23 and trailed unit hitch 31. As the tow hitch member passes the terminal end of the latch arms 28, the latch member 40 contacts landing surface 55 which pivots the latch member body 41 and arm 46 against the biasing force provided by spring 47, allowing continued upwards movement. As the tow hitch member 21 approaches the towing position, the latch member arm 46 is rotated into recess 43 on the latch arms 28 and stop surface 21-4 contacts the underside of the closing plate 31, thereby securing the tow hitch 23 in position and preventing unintentional upwards and downwards movement. To release the trailing, the operator moves the release lever 50 into a latch member release position which provides tension to cable 52 which rotates the latch member 40 against the biasing element 47. and out of the recess 43. The operator can then operate the control for lowering the tow hitch 23 by activating the same "lower tow hitch" input device on an operator console as used to lower the tow hitch from the stowed position. This causes the hydraulic cylinders 36a and 36b to retract and the tow hitch member 21 to pivot down to the loading position once more. Once the trailed unit hitch 31 has been removed from the tow hitch 23, the operator raises the tow hitch member 21 using the same raise tow hitch input device as used previously. However, the release lever is used contemporaneously to shift the latch arms 28 into the intersecting path above the runners 56. This causes the underside of the latch arms 28 to engage the runners 56 as the tow hitch member 21 continues to rise until the latch arms 28 and closing plate 30 are provided in the retracted position, and the tow hitch member 21 and tow hitch 23 are in the stowed position. Upon reaching the stowed position, the operator release lever 50 can be released, causing the latch arm lever 57 to rotate back into the neutral position and receive the cross-member within the notch 61, thereby restricting movement of the tow hitch member 21 until the release lever 50 is operated again to allow lowering once more. The one or more embodiments are described above by way of example only and it will be appreciated that various modifications are possible without departing from the scope of protection afforded by the appended claims.

Claims

1. A working machine (1) comprising:a chassis (19);an operator structure (3) mounted to the chassis;a ground engaging structure (4,5) mounted to the chassis;a prime mover (12) for providing motive power to the ground engaging structure; a working arm (6) pivotally mounted to the chassis;a rear mounted tow hitch arrangement (20) comprising:a tow hitch member (21) pivotably mounted to a rear body portion (10) of the working vehicle at a first end thereof and comprising a tow hitch (23) at a second end thereof, wherein the tow hitch member is pivotable between:a stowed position in which the tow hitch is housed within the rear body portion; and,a towing position in which the tow hitch is external to the rear body portion and configured retain a tow hitch of a trailer to be towed.

2. The working vehicle of claim 1, further comprising an actuation arrangement (34) configured to move the tow hitch between the stowed and towing positions.

3. The working vehicle of claims 1 or 2, wherein the tow hitch member is further pivotable into a lowermost loading position in which the tow hitch is external to the rear body portion and positioned to receive a tow hitch of a trailed unit to be towed.

4. The working vehicle of any preceding claim, wherein an underside of the rear body portion defines an upwardly angled portion which defines the angle at which the machine can be orientated in relation to a rearward ground surface, wherein the tow hitch is located inboard of the upwardly angled portion when in the stowed position and outboard of the upwardly angled portion when in the towing position, or lowermost loading position when dependent on claim 3.

5. The working vehicle of claim 4, wherein the upwardly angled portion defines a plane (11) which extends upwardly rearward and between lateral portions of the rear body portion.

6. The working vehicle of any preceding claim, wherein the tow hitch member is longitudinal and pivots in a plane parallel to a longitudinal axis of the working machine.

7. The working vehicle of any preceding claim, wherein the actuation arrangement comprises a linear actuator (34), e.g. a hydraulic cylinder, which is linearly extendable to pivot the tow hitch between the stowed and towing positions.

8. The working vehicle of claim 7 when dependent on claim 3, wherein the linear actuator is configured to raise the tow hitch from the lowermost loading position when a load is attached.

9. The working vehicle of any preceding claim, further comprising a latch assembly movable between a first engaged position and a second released position, wherein the tow hitch is restrained from being lowered when in the engaged first position, and free to be lowered using the actuation arrangement when in the second released position.

10. The working vehicle of claim 9, wherein the latch assembly is remotely operable from the operator structure.

11. The working vehicle of claims 9 or 10, wherein the latch assembly comprises a latch arm (28) mounted to the chassis and a latch member (40) mounted to the tow hitch member, the latch arm and latch member are releasably engageable to provide the mechanical restraint and, optionally, the releasable engagement is provided by pivoting the latch arm or latch member relative to the other of the latch arm and latch member.

12. The working machine of claim 11, wherein the latch arm which is pivotably mounted to the chassis, and the latch member mounted to the tow hitch member.

13. The working vehicle of claim 12, wherein the latch arm extends downwardly from the rear body portion and is configured to move between an extended position and a retracted position, the extended and retracted positions corresponding respectively to the stowed and towing positions of the tow hitch member.

14. The working vehicle of claim 13, wherein tow hitch arrangement is configured to move the latch arm from the extended position to the retracted position as the tow hitch member is moved from the towing position to the stowed position.

15. The working vehicle of claim 14, wherein the latch assembly comprises a latch arm release mechanism configured to release and / or move the latch arm from theextended position towards the retracted position to allow the tow hitch member to be raised, wherein, optionally, the latch arm release mechanism is provided in the operator structure.

16. The working vehicle of claims 13 or 14, wherein the latch arm comprises an engagement feature configured to contact a running surface of the tow hitch member, wherein moving the tow hitch member from the towing position to the stowed position causes the engagement feature to slide along the running surface thereby moving the latch arm into the retracted position.

17. The working vehicle of any preceding claim, wherein the tow hitch comprises a hook for receiving a trailer hitch of the trailer to be towed, wherein the hook is provided below and proximate a closing plate positioned to prevent removal of the trailer hitch when in the towing position.

18. The working vehicle of claim 17, wherein the closing plate is configured to move between an deployed position and a retracted position, the deployed and retracted positions corresponding respectively to the stowed and towing positions of the tow hitch member.

19. The working vehicle of claim 18, when dependent on any of claims 12 to 18, wherein the latch arm comprises the closing plate such that the hitch arm and closing plate move concurrently between the extended and retracted positions.

20. The working vehicle of any of claims 17 to 19 when dependent on claim 3, wherein tow hitch member is moved towards the closing plate when moving from the lowermost loading position to the towing position.

21. The working vehicle of any preceding claim further comprising a stowed keep configured to engage with the tow hitch member when in the stowed position to prevent unintentional lowering of the tow hitch member, wherein, optionally, the stowed keep is configured to be disengaged by an operator prior to lowering the tow hitch member.

22. The working vehicle of claim 21 when dependent on claim 15, wherein the stowed keep and latch arm release mechanism are actuable from the operator structure using a common control device.

Images