[0001] This invention relates to a load handling apparatus of the kind which is movable
under its own power over the ground and has a loader arm, or arms, which carries a
loading implement.
[0002] Such apparatus are popularly used for examples only on building sites to load and
unload building materials etc., and in the agricultural industry for loading and unloading
agricultural materials.
[0003] Loader arms are known which are telescopic to allow greater reach. To enable an operator
to have a sufficiently clear view for safe working when the arm is telescoped outwardly
for example and a load is being handled at height, it is essential that the operator
is as high up as possible. However this restricts the ability of the apparatus to
be used in environments where height is restricted, such as within a freight container.
[0004] According to a first aspect of the invention we provide a load handling apparatus
including a body, a power operated motive means, a front axle and a rear axle, the
axles each carrying ground engaging means on which the apparatus may move over the
ground, at least one loader arm supported at or adjacent one end on the body for movement
about a generally horizontal axis, the loader arm being adapted to carry a loading
implement at or adjacent a second end thereof, the apparatus further including an
operator's cab, characterised in that means are provided to move the cab generally
upwardly and downwardly between upper and lower positions relative to the ground engaging
means.
[0005] Thus a load handling apparatus is provided which is capable of working in an environment
where height is restricted, e.g. with the operator's cab in the lower position, and
in situations where the operator's cab needs to be at an elevated height, i.e. in
the upper position for safe working. Usually the top of the cab will be the restricting
factor on the height of the apparatus at least when the operator's cab is in the upper
position and the loader arm is in a lowered position, but when in the lower position
the top of the operator's cab may be lower than another part of the apparatus such
as the uppermost part of the lowered loader arm.
[0006] Most conveniently to facilitate load handling in restricted conditions such as within
a freight container, the operator's cab is provided at or adjacent a front end of
the body.
[0007] Although the entire body may be lifted and lowered relative to the ground engaging
means, preferably the body provides a mounting means on which the operator's cab is
carried for movement upwardly and downwardly whereby the operator's cab is moveable
upwardly and downwardly relative to the body of the apparatus. Such a mounting means
may for example comprise a guide means and the operator's cab may comprise a follower
means, there being actuator means such as one or more fluid operated actuators or
one or more mechanical drives, such as one or more threaded lead screws, to move the
follower means relative to the guide means.
[0008] Preferably the loader arm extends forwardly of the operator's cab and the generally
horizontal axis about which the loader arm moves, is located rearwardly of the operator's
cab.
[0009] The power operated motive means may comprise an engine mounted generally rearwardly
of the body, and there being a transmission, which may for examples be mechanical
or hydrostatic or a hybrid of both, to transmit drive to the ground engaging means
carried by at least one of the front and rear axles.
[0010] For greater flexibility of use, the loader arm may be mounted at or adjacent one
side of the body and the operator's cab may be located generally at an opposite side
of the body so that the loader arm may be lifted and lowered about the generally horizontal
axis, which may be located above the level of the ground engaging means, by the side
of the operator's cab.
[0011] If desired only the ground engaging means of the front axle or the rear axle is steerable.
For greater manoeuvrability though, preferably the ground engaging means of both the
front and rear axles are steerable although preferably means are provided to lock
the ground engaging means of one of the front and rear axles in a set position, usually
straight ahead, so as to achieve steering only with a fully steerable ground engaging
means of one of the axles when required.
[0012] In each case the fully steerable ground engaging means with which such locking means
is not provided, is preferably steered by means of a mechanical connection with a
steering control operated from within the operator's cab, so that the apparatus complies
with legislation which demands mechanical steering for on-road use, at least above
a minimum speed.
[0013] Thus the apparatus may be used on rough terrain and driven on the road like a conventional
vehicle at speeds exceeding those set for conventional load handling apparatus which
have fluid operated steering.
[0014] In one arrangement to accommodate lifting and lowering of the operator's cab at the
front of the apparatus, the fully steerable ground engaging means may be on the front
axle and the mechanical connection includes a telescopic assembly whereby the mechanical
connection is retained as the operator's cab is lifted and lowered. The telescopic
assembly may for example include a splined shaft and a correspondingly splined receiving
member which can relatively telescope and retain a driving connection.
[0015] Power means such as fluid operated power means may be provided to assist steering
of the fully steerable ground engaging means, and preferably to effect steering of
the ground engaging means on the other axle which can be locked in the set position.
[0016] The power steering means of the lockable ground engaging means may be operable in
concert with the power assisted means which assist steering of the fully steerable
ground engaging means.
[0017] If desired, to facilitate load handling in confined spaces the loading implement
is mounted at or adjacent the second end of the loader arm on a carriage by means
of which the loading implement is movable in a transverse direction relative to the
loader arm.
[0018] Where the loading implement comprises pair of loading forks, the forks may be movable
relative to each in the transverse direction. This may be achieved by the carriage
including a threaded member which has oppositely male threaded regions each carrying
a respective female threaded member on which one of the loading forks is mounted,
and there being means to rotate the male threaded member.
[0019] Where load handling apparatus is used solely on rough terrain, it is usual for the
front and rear axles to be attached directly to the body of the apparatus e.g. with
each axle pivoted at a central position to the body. Such an arrangement severely
limits the speed. To enable such an apparatus to be driven on the road at faster speeds
a suspension is required but the provision of a suspension ordinarily may compromise
the ability of the apparatus to perform on rough terrain.
[0020] Thus to accommodate these conflicting requirements at least one of the front and
rear axles which carries ground engaging means which in use transmit driving torque
to the ground, may be suspended from the body by means of a non-reactive suspension
in which there is no significant change in the vertical loading on the ground engaging
means in response to changes in the driving torque applied thereto.
[0021] The non-reactive suspension may comprise a pair of links at either side of the body,
one link of each pair being above the other relative to the ground, the upper link
of each pair being pivotably connected at a first end relative to the body and at
a second end to the axle at a first position and the lower link of each pair being
pivotally connected at a first end relative to the body and at a second end to the
axle at a second position, the second positions each being below their respective
first positions. However other non-reactive suspension arrangements are possible.
[0022] In a preferred apparatus the ground engaging means of each of the front and rear
axles is adapted to transmit driving torque to the ground and each of the front and
rear axles is suspended from the body by non-reactive suspension means although means
may be provided to disconnect driving torque transmission to one of the ground engaging
means when required, e.g. for on-road use..
[0023] A level sensing means is preferably provided at each side of the apparatus, for the
or each axle which is suspended from the body by non-reactive suspension means, the
level sensing means in use sensing changes in the distance between the axle and the
body at the respective side caused by changes in the ground surface over which the
apparatus travels, and there being a height regulating means for each level sensing
means which is responsive to the respective level sensing means to adjust the distance
between the axle and the body to return the axle at the respective side of the apparatus
to a datum position relative to the body.
[0024] According to a second aspect of the invention we provide a load handling apparatus
including a body, a power operated motive means, a front axle and a rear axle, the
axles each carrying ground engaging means on which the apparatus may move over the
ground, at least one loader arm supported at or adjacent one end on the body for movement
about a generally horizontal axis, the loader arm being adapted to carry a loading
implement at or adjacent a second end thereof, the apparatus further including an
operator's cab, characterised in that the ground engaging means of the front and rear
axles are steerable and means are provided to lock the ground engaging means of one
of the front and rear axles in a set position so as to achieve steering only with
a fully steerable ground engaging means of one of the axles when required, the fully
steerable ground engaging means being steerable by means of a mechanical connection
with a steering control operated from within the operator's cab and there being power
means provided to assist steering of the fully steerable ground engaging means, the
ground engaging means which can be locked in a set position being steerable by power
means, and the power steering means of the lockable ground engaging means being operable
in concert with the power assisted means which assist steering of the fully steerable
ground engaging means.
[0025] The apparatus of the second aspect of the invention may have any of the features
of the apparatus of the first aspect of the invention.
[0026] According to a third aspect of the invention we provide a load handling apparatus
including a body, a power operated motive means, a front axle and a rear axle, the
axles each carrying ground engaging means on which the apparatus may move over the
ground, at least one loader arm supported at or adjacent one end on the body for movement
about a generally horizontal axis, the loader arm being adapted to carry a loading
implement at or adjacent a second end thereof, the apparatus further including an
operator's cab, characterised in that loading implement comprises a pair of loading
forks, the forks being movable relative to each in the transverse direction.
[0027] The apparatus of the third aspect of the invention may have any of the features of
the apparatus according to the first and/or second aspects of the invention.
[0028] According to a fourth aspect of the invention we provide a load handling apparatus
including a body, a power operated motive means, a front axle and a rear axle, the
axles each carrying ground engaging means on which the apparatus may move over the
ground, at least one loader arm supported at or adjacent one end on the body for movement
about a generally horizontal axis, the loader arm being adapted to carry a loading
implement at or adjacent a second end thereof, the apparatus further including an
operator's cab, characterised in that at least one of the front and rear axles which
carries ground engaging means which in use transmit driving torque to the ground,
is suspended from the body by means of a non-reactive suspension in which there is
no significant change in the vertical loading on the ground engaging means in response
to changes in the driving torque applied thereto.
[0029] The apparatus according to the fourth aspect of the invention may have any of the
features of the apparatus of the first and/or second and/or third aspects of the invention.
[0030] The invention will now be described with reference to the accompanying drawings in
which:-
FIGURE 1 is an illustrative side view of a load handling apparatus in accordance with
the invention shown with a loader arm thereof in a lowered condition, the apparatus
being shown working within a freight container;
FIGURE 2 is a similar view to figure 1 but showing an operator's cab and the loader
arm in a raised condition, alongside a lorry;
FIGURE 3 is an illustrative plan view of the apparatus of figures 1 and 2;
FIGURE 4 is an illustrative plan view showing a loading implement of the apparatus
of figures 1 to 3 in alternative positions;
FIGURE 5 is an illustrative perspective view of the apparatus of figures 1 to 3 showing
the suspension arrangement;
FIGURE 6 is a view similar to figure 5 but showing the steering arrangement.
[0031] Referring to the drawings, a load handling apparatus 10 comprises a body 11 at a
rear end of which there is provided a power operated motive means which in this embodiment
is an engine 14 which in this example is longitudinally disposed but could be arranged
transversely relative to a centre line A of the apparatus 10. Instead of an engine,
a motor or some other suitable power operated motive means could alternatively be
provided. The engine 14 is operative to provide driving torque to front 16, or front
and rear drive wheels 16,17, as hereinafter described, and to provide power to drive
a hydraulic pump (not shown) which provides pressurised fluid to operate actuators
as hereinafter described.
[0032] Mounted on the body 11 is a telescopically extendable loader arm 18. The loader arm
18 is arranged at one side of the body 11 as can be seen best in figure 3, and is
mounted adjacent a first end 19 on the body 11 for upward and downward movement about
a generally horizontal axis B. At a second opposite end 20 of the loader arm 18 there
is provided a loading implement 21 which in this example is a pair of loading forks
22,23 on a carriage 24, but could be an alternative kind of loading implement such
as for example only, a loading bucket.
[0033] The loader arm 18 may be telescopically extended by any desired means such as one
or more fluid operated actuators (not shown) between a refracted condition as seen
in figure 1 and an extended condition shown in figure 2.
[0034] Mounted at a front end 26 of the body 11, there is an operator's cab 28 from which
the apparatus 10 may be controlled. Within the cab 28 there is a steering control,
such as a steering wheel 29, and the usual engine and actuator controls.
[0035] The cab 28 is mounted on a mounting means 30 which comprises in this example a pair
of guides 31 which may be provided by re-entrant channels or the like, and the cab
28 includes followers 32 which may slide up and down in the guides 31. The cab 28
may be lifted and lowered relative to the body 11 by any desired powered means. In
one arrangement, the guides 31 may each have a hydraulic or other fluid operated actuator
therein, but preferably each guide has a lead screw 33 or other threaded member, the
followers 32 comprising female threaded parts which ride up and down the lead screws
33 as the lead screws are turned by some motive means.
[0036] In each case, the cab 28 may be moved between a lower position shown in figure 1
and an upper position shown in figure 2 relative to the body 11 and thus relative
to the wheels 16,17, by a control preferably within the operator's cab 28.
[0037] It can be seen from figure 1 that a top surface 34 of the cab 28 is the uppermost
part of the apparatus 10 when the cab 28 is in its lower position and that overall
the apparatus 10 is therefore sufficiently low to enable the apparatus 10 to be driven
into height restricted area, such as within a freight container 35 as shown. The loader
arm 18 is still able to be operated within a limited lifting range and so the apparatus
10 may be used for handling e.g. palletted loads 36 or other loads within the container
35.
[0038] However, to enable an operator within the cab 28 to have as clear a view as possible
e.g. when operating the apparatus 10 with the loader arm 18 extended and elevated
as seen in figure 2 , e.g. to load or unload the palletted loads 36 onto the bed 37
of a lorry 39, the cab 28 may be raised towards its upper position.
[0039] This provides a further advantage in that in the event that the apparatus 10 is required
to be driven into and/or operated in water or the like, which with the cab 28 in the
lower position as indicated in figure 1 would be at a high level, the cab 28 may be
raised so that no or a minimal amount of the cab 28 will be submerged in the water.
Thus by ensuring that water sensitive components such as electronic controls, instrumentation,
radio and the like are at as high a possible position in the cab 28, these may be
protected from water damage.
[0040] The loader arm 18 may be raised and lowered about axis B using conventional lifting
and lowering technology. For example as shown, there is provided a lifting actuator
40 which may be actuated by hydraulic fluid provided by the hydraulic pump, and the
loading implement 21, or more importantly a load carried thereby, may be maintained
in a substantially level orientation by fluid in a compensating actuator 41 being
exchanged with fluid of a tipping actuator 42 as the loader arm 18 is lifted and lowered.
[0041] Driving torque is transmitted from the engine 14 to the ground wheels 16,17 by a
transmission which includes a gearbox which is mounted generally beneath the level
of the loader arm axis B, generally centrally of the apparatus 10. The gearbox includes
a pair of output shafts which are coupled via universal joints etc. to respective
front 46 and rear 47 axles on which the drive wheels 16, 17 respectively are mounted.
The gearbox may include means to enable drive to the front wheels 16 of axle 46 to
be disconnected from the drive train whilst drive to the rear wheels 17 of axle 47
is maintained, such disconnection means comprising a clutch or the like. Thus the
apparatus 10 may be driven by two or four wheels as desired.
[0042] The apparatus 10 is capable of being steered either using the front wheels 16 alone,
or in combination with the rear wheels 17. To achieve this each of the wheels 16,17
are mounted in trunnions of their respective axles 46,47.
[0043] In the case of the front wheels 16, there is a mechanical connection between the
front wheels 16 and the steering wheel 29 which includes a telescopic arrangement
49 to enable the mechanical connection to be maintained as the cab 28 is lifted and
lowered. Otherwise movements of the steering wheel 29 are transmitted to the front
wheels 16 via a steering box 50 and steering swivel 51. The telescopic arrangement
49 includes a splined shaft 53 and correspondingly splined receiving member 54, which
splines remain in engagement as the shaft 53 telescopes inwardly and outwardly of
the receiving member 54 in response to downward and upward movement of the cab 28,
[0044] Steering is power assisted, there being a fluid (hydraulic) operated actuator 55
to achieve this.
[0045] In the case of the rear wheels 17, these are steered by means of a hydraulic actuator
60 (or actuators) which is coupled to the rear wheels 17 via a relay lever system
61. The assisting actuator 55 for the front wheels 16 is coupled operationally to
the rear wheel steer actuator 60. For example both may be contained within a common
hydraulic circuit in which fluid expelled from the front wheel 16 steer assisting
actuator 55 drives the rear wheel steer actuator 60 whereby the two actuators 55,
60 operate in concert
[0046] From figure 3 it may be appreciated that the front 16 and rear 17 wheels may be operated
in so called crab mode in which the front 16 and rear 17 wheels are operated in unison
and turn in the same direction, or alternatively so called cramp mode in which the
front 16 and rear wheels 17 operate in unison but turn in opposite directions. Change
over between four wheel steer in cramp and crab modes may be achieved by a hydraulic
change over valve, which may also alternatively enable the rear wheels 17 to be locked
in a straight ahead set position so that two wheel steering using the front wheels
16 only may be performed e.g. for on-road use.
[0047] The hydraulic change over valve may be controlled using an electronic control system
which may incorporate proximity sensors or the like to determine at least when the
rear wheels 17 are in their straight ahead positions.
[0048] The electronic control system may be adapted only to allow four wheel steering when
the apparatus 10 is travelling over the ground below a predetermined set speed and
may prevent change over between two and four wheel steering modes while the apparatus
10 is in motion.
[0049] Steering may otherwise be controlled as desired.
[0050] The engine 14 may include a cooling unit 65 which may be operative to cool the engine
14 and/or the hydraulic fluid used by the various actuators. Conveniently the cooling
unit 65 is located longitudinally of the apparatus 10 between the engine 14 and the
loader arm 18.
[0051] It will be appreciated from figure 1 that manoeuvrability of the apparatus 10 within
a freight container 35 is restricted. Often it will not be possible to handle palletted
loads 36 at both sides of the container 35 by manoeuvring the apparatus 10.
[0052] Referring to figure 4 it can be seen that the loading implement 21 i.e. the forks
22,23, may be shifted sideways on the carriage 24 relative to the loader arm 18 so
that a first pallet 36a may be handled in one corner of the container 35 with the
forks 22,23 at one extreme of sideways movement and a second pallet 36b may be handled
in an opposite corner of the container 35 with the forks 22,23 in an opposite extreme
of sideways movement.
[0053] Such carriage 24 sideways movement may be achieved by means of an actuator, or a
lead screw or other threaded member which is rotated.
[0054] Furthermore, for added manoeuvrability, where the loading implement 21 comprises
a pair of forks 22,23, the forks 22,23 may be arranged to be movable transversely
towards and away from one another on the carriage 24 to vary the spacing between them.
This may most conveniently be achieved by means of a threaded member which is threaded
oppositely along different regions thereof, with each of the forks 22,23 having a
female threaded part which traverses the threaded member in an opposite direction
to the female threaded part of the other of the pair of forks 22,23 as the threaded
member is rotated e.g. by means of a motor or some other suitable electric, hydraulic
or other motive means.
[0055] However adjustment of the spacing between the forks 22,23 of the pair may otherwise
be achieved as desired.
[0056] Referring now particularly to figure 5 the suspension arrangement of the apparatus
10 is shown.
[0057] The front 46 and rear axles 47 (not shown in figure 5 for clarity) are suspended
from the body 11 of the apparatus 10 by respective non-reactive suspensions. Throughout
this specification, by "non-reactive" we mean that the vertical load on the respective
ground engaging wheels 16,17 carried by their axles, and hence the traction between
the ground engaging wheels and the ground, does not significantly fluctuate in response
to changes in the driving torque applied to the ground engaging wheels by the engine
14 via the transmission.
[0058] The suspension for the front axle 46 comprises at each side of the apparatus 10,
an upper leading link 68 which is connected at one end 69 at a first position to the
front axle 46, and at an opposite end 71 to the body 11, and a lower leading link
72 which is connected at one end at a second position 73 to the front axle, and at
an opposite end 74 to the body 11, the first position 69 being above the second position
73 and the points of connection of the upper links 68 to the body 11 being above the
points of connection of the lower links 72 to the body 11.
[0059] The front axle 46 further is located by means of a Panhard rod 75 which stabilises
the front axle, provides reaction to the steering mechanism and affects roll steer
and bump steer characteristics.
[0060] Front axle 46 movement relative to the body 11 is damped by damping members 76 which
in this example comprise hydropneumatic springs the resistance of which is controlled
as a function of the level of the axle 46 at the respective axle end, relative to
the body 11. This is achieved in this example by utilising a level sensing means comprising
a fluid filled cylinder 78 which is coupled between the body 11 and axle 46. The sensing
means 78 controls the flow of hydraulic fluid to and from the hydropneumatic springs
76, which fluid is separated from a gas chamber therein by a suitable diaphragm. The
hydraulic pressure in the springs 76 controls the degree of pneumatic damping provided
by the springs 76, so that the greater the displacement of the front axle 76 at a
respective side of the apparatus 10 relative to the body 11, the greater the damping
provided.
[0061] Additionally, the hydropneumatic springs 76 may include mechanical damping elements
such as mechanical springs and resilient end stops to enable the suspension to handle
sudden and large axle 46 displacements as may occur when the apparatus 10 is travelling
over very rough ground.
[0062] The rear axle 47 is suspended from the body by a similar non-reactive suspension
arrangement, although instead of a pair of leading suspension links 68,72 at each
side of the apparatus 10, a lower pair 80,81 of trailing links are provided, which
are pivotably connected at respective first ends 83,84 to the axle 47, and at respective
second ends 85,86 to the body 11. An upper pair of links 88,89 is also provided but
these are pivotably connected at respective first ends 90,91 to the axle 47, but are
pivotably connected to each other and to the body 11 at respective second ends 93,
so that the upper links 88,89 are in a generally "V" configuration.
[0063] Damping is again provided by a pair of hydropneumatic springs 94,95 and a level sensing
means 96,97 is provided at each axle 47 side to sense the displacement of the axle
47 relative to the body 11 at each side and to control the flow of hydraulic fluid
to the springs 94,95 to control the degree of damping provided thereby.
[0064] By virtue of the non-reactive suspension being provided for the front and rear axles
46,47 the apparatus 10 is inherently able to manoeuvre on rough terrain and is able
to travel at relatively fast speed on smoother terrain, such as on the road.
[0065] For rough terrain use, the apparatus 10 will tend to be operated in four wheel drive
mode, i.e. with driving torque being transmitted to all four wheels 16,17, and may
be operated in two or four wheel steer as desired. For on-road use, the apparatus
10 will tend to be operated in two wheel steer mode and in two wheel drive mode.
[0066] By virtue of the combination of the ability of the apparatus 10 to be operated selectively
in each of these driving modes, and the provision of a cab 28 which can be raised
and lowered and the provision of a loading implement comprising particularly loading
forks 22,23 the spacing between which and their transverse position on the loader
arm 18, can be adjusted, a load handling apparatus of great versatility is provided.
[0067] However various modifications may be made without departing from the scope of the
invention.
[0068] For example, although the cab 28 is shown at a front end 26 of the body 11 of the
apparatus 10, the cab 28 may be provided more rearwards and may be provided more centrally
than the position shown.
[0069] The engine 14 may be mounted more centrally of the apparatus 10 and may be provided
in a lower position than shown.
[0070] In another arrangement which is not intended for on-road use and thus need not comply
with the appropriate legislation, front wheel 16 steering may be effected by solely
hydraulic means such as described for the rear wheels 17, or otherwise. Alternatively
the apparatus 10 may be adapted for rear wheel 17 steering on the road so that the
mechanical steering connection required to comply with highway legislation, may be
to the rear wheels 17 rather than the front wheels 16.
[0071] Instead of the cab 28 being movable up and down on a generally upright mounting means
30, the cab 28 may be movable up and down on a linkage arrangement.
[0072] It will be appreciated that although an apparatus 10 having each of the features
of
a) a cab 28 which can be raised and lowered;
b) a combination of mechanical front wheel and power driven rear wheel steering;
c) non-reactive suspension for one or both of the front and rear axles;
d) relatively transversely adjustable loading forks;
has been described, the advantages of these features may be individually realised
on an apparatus 10 having only one or any combination of some of these features as
desired.
[0073] Although the invention has been described with particular reference to a wheeled
apparatus having front 16 and rear wheels 17, the invention may be applied to a load
handling apparatus comprising half or full tracks although such apparatus may not
be as able as a fully wheeled vehicle to travel at relatively fast speed e.g. on the
road.
[0074] The features disclosed in the foregoing description, or the following claims, or
the accompanying drawings, expressed in their specific forms or in terms of a means
for performing the disclosed function, or a method or process for attaining the disclosed
result, as appropriate, may, separately, or in any combination of such features, be
utilised for realising the invention in diverse forms thereof.
1. A load handling apparatus (10) including a body (11), a power operated motive means
(14), a front axle (46) and a rear axle (47), the axles (46, 47) each carrying ground
engaging means (16, 17) on which the apparatus (10) may move over the ground, at least
one loader arm (18) supported at or adjacent one end (19) on the body (11) for movement
about a generally horizontal axis (B), the loader arm (18) being adapted to carry
a loading implement (21) at or adjacent a second end (20) thereof, the apparatus (10)
further including an operator's cab (28), characterised in that means (30-33) are
provided to move the cab (28) generally upwardly and downwardly between upper and
lower positions relative to the ground engaging means (16, 17).
2. An apparatus (10) according to claim 1 characterised in that the operator's cab is
provided at or adjacent a front end of the body where the body provides a mounting
means (30) on which the operator's cab (28) is carried for movement upwardly and downwardly
whereby the operator's cab (28) is moveable upwardly and downwardly relative to the
body (11) of the apparatus (10), the mounting means (30) comprising a guide means
(31) and the operator's cab (28) comprising a follower means (32), there being actuator
means (33) to move the follower means (32) relative to the guide means (31).
3. An apparatus (10) according to claims 1 or claim 2 characterised in that the loader
arm (18) extends forwardly of the operator's cab (28) and the generally horizontal
axis (B) about which the loader arm (18) moves, is located rearwardly of the operator's
cab (28) at or adjacent one side of the body (11), and the operator's cab (28) is
located generally at an opposite side of the body (11), the generally horizontal axis
(B) about which the loader arm (18)moves, being located above the level of the ground
engaging means (16, 17).
4. An apparatus (10) according to any one of the preceding claims characterised in that
the front and rear axles (46, 47) are steerable and means are provided to lock one
of the front and rear axles (46, 47) in a set position so as to achieve single axle
steering only when required with a single fully steerable ground engaging means (16,
17), and wherein the fully steerable ground engaging means (16, 17) is steered by
means of a mechanical connection (49, 50, 51) between a steering control operated
from within the operator's cab (28) and the ground engaging means (16, 17), the mechanical
connection (49, 50, 51) includes a telescopic assembly (49) whereby the mechanical
connection is retained as the operator's cab (28) is lifted and lowered.
5. An apparatus (10) according to any one of the preceding claims characterised in that
the loading implement (21) is mounted at or adjacent the second end (20) of the loader
arm (18) on a carriage (24) by means of which the loading implement (21) is movable
in a transverse direction relative to the loader arm (18), the loading implement comprising
pair of loading forks (22, 23), the forks being movable relative to each other in
a transverse direction, the carriage (24) including a threaded member which has oppositely
male threaded regions each carrying a respective female threaded member on which one
of the loading forks (22, 23) is mounted, and there being means to rotate the male
threaded member.
6. An apparatus (10) according to any one of the preceding claims characterised in that
at least one of the front and rear axles (46, 47) which carries ground engaging means
(16, 17) which in use transmit driving torque to the ground, is suspended from the
body (11) by means of a non-reactive suspension in which there is no significant change
in the vertical loading on the ground engaging means (16, 17) in response to changes
in the driving torque applied thereto.
7. An apparatus (10) according to claim 6 characterised in that the non-reactive suspension
comprises a pair of links (68, 72) at either side of the body (11), one link (68)
of each pair being above the other (72) relative to the ground, the upper link (68)
of each pair being pivotally connected at a first end (69) relative to the body (11)
and at a second end to the axle (46, 47) at a first position and the lower link (72)
of each pair being pivotally connected at a first end relative to the body (11) and
at a second end to the axle (46, 47) at a second position (73), the second positions
(73) each being below their respective first positions.
8. An apparatus (10) according to claims 6 or claim 7 characterised in that a level sensing
means (78) is provided at each side of the apparatus (10), for the or each axle (46,
47) which is suspended from the body by non-reactive suspension means, the level sensing
means (78) in use sensing changes in the distance between the axle (46, 47) and the
body (11) at the respective sides caused by changes in the ground surface over which
the apparatus (10) travels, and there being a height regulating means (76) for each
level sensing means (78) which is responsive to the respective level sensing means
(78) to adjust the distance between the axle (46, 47) and the body (11) to return
the axle (46, 47) at the respective side of the apparatus (10) to a datum position
relative to the body (11).
9. A load handling apparatus (10) including a body (11), a power operated motive means
(14), a front axle (46) and a rear axle (47), the axles (46, 47) each carrying ground
engaging means (16, 17) on which the apparatus (10) may move over the ground, at least
one loader arm (18) supported at or adjacent one end on the body (11) for movement
about a generally horizontal axis (B), the loader arm (18) being adapted to carry
a loading implement (21) at or adjacent a second end thereof, the apparatus (10) further
including an operator's cab (28), characterised in that the front and rear axles (46,
47) are steerable and means are provided to lock one of the front and rear axles (46,
47) in a set position so as to achieve single axle steering only when required with
a single fully steerable ground engaging means (16, 17), the fully steerable ground
engaging means (16, 17) being steerable by means of a mechanical connection (49, 50,
51) between a steering control operated from within the operator's cab (28) and the
ground engaging means (16, 17) and there being power means provided to assist steering
of the fully steerable ground engaging means (16, 17), the axle (46, 47) which can
be locked in a set position being steerable by power means, and the power steering
means of the lockable ground engaging means (16, 17) being operable in concert with
the power assisted means which assist steering of the fully steerable ground engaging
means (16, 17).
10. A load handling apparatus (10) including a body (11), a power operated motive means
(14), a front axle (46) and a rear axle (47), the axles (46, 47) each carrying ground
engaging means (16, 17) on which the apparatus (11) may move over the ground, at least
one loader arm (18) supported at or adjacent one end on the body (11) for movement
about a generally horizontal axis (B), the loader arm (18) being adapted to carry
a loading implement (21) at or adjacent a second end thereof, the apparatus (10) further
including an operator's cab (28), characterised in that the loading implement (21)
includes a pair of forks (22, 23) and the forks (22, 23) are movable relative to each
in a transverse direction.
11. A load handling apparatus (10) including a body (11), a power operated motive means
(14), a front axle (46) and a rear axle (47), the axles (46, 47) each carrying ground
engaging means (16, 17) on which the apparatus (10) may move over the ground, at least
one loader arm (18) supported at or adjacent one end on the body (11) for movement
about a generally horizontal axis (B), the loader arm (18) being adapted to carry
a loading implement (21) at or adjacent a second end thereof, the apparatus (10) further
including an operator's cab (28), characterised in that at least one of the front
and rear axles (46, 47) which carries ground engaging means (16, 17) which in use
transmit driving torque to the ground, is suspended from the body (11) by means of
a non-reactive suspension in which there is no significant change in the vertical
loading on the ground engaging means (16, 17) in response to changes in the driving
torque applied thereto.