EP0579780A4

EP0579780A4 - Container transporter

Info

Publication number: EP0579780A4
Application number: EP19920917336
Authority: EP
Inventors: Clark Simpson; John Hodgman
Original assignee: Clark Material Handling Co
Current assignee: Clark Material Handling Co
Priority date: 1991-04-10
Filing date: 1992-02-27
Publication date: 1994-06-29
Also published as: CA2105465A1; EP0579780A1; WO1993007041A1; JPH07502240A

Abstract

A self-propelled, counterbalanced, container (52) transporter has a frame (62), a counterweight (60) supported at the rear, an elevating upright (29), carriage pick-up and lift frame assembly (40) for lifting, transporting and stacking containers (52) at the front. The frame (62) has a tower structure (66) supporting a cab (16) having a wide angle front window area (22) that partially wraps around the operator's station to permit a horizontal line of sight to the maximum extension of the lift frame (40) and is sloped back to afford high angle vision to the maximum vertical extension of the upright for high stacking containers (52). The tower structure (66) is positioned rearwardly of the center, and projects upwardly to a height that provides an elevated line of sight from the cab (16) through the upright. Engine exhaust gases are routed to the front and out through the top of the upright (29) thereby reducing noise and exhaust emission levels in the cab (16). A hydraulic circuit (105, 107, 108) is phased to deliver lifting pressure according to the lifted weight and engine speed matching loads with engine torque thereby increasing productivity by achieving higher lift speeds for light or empty containers (52).

Description

CONTAINER TRANSPORTER

The Field of Art

The field of art to which the invention pertains relates to large, self-propelled, load handling vehicles primarily used for picking up, transporting and stacking ISO shipping containers stored at wharfs, container yards or transport terminals.

Background of the Invention

Various transport machines exist in the prior art for lifting, loading and stacking containers ranging from cranes and derricks to forms of straddle lift van carriers and lift trucks equipped with special gooseneck and lift frame attachment.

The containers themselves come in twenty or forty foot lengths and are standardized, in dimension for volumetric uniformity, as set forth in the American National Standards Institute (ANSI), 1430 Broadway Street, New York standards entitled "Specifications for Cargo Containers" (publication number MH5.1-1965).

It is common practice around docks, wharfs or transport terminals to use large lift trucks as container handlers by outfitting them with a gooseneck from which is suspended a lift frame, a rectangular structure having hydraulically extendable ends to accommodate either the twenty or forty foot container. At the corners of the lift frame are twist locks which engage standardized receptacles in upper corners of the container when the lift frame is lowered onto container.

Such a lift frame is described in United States Patent 3,764,032 issued October 9, 1973 and titled "Container Handling Device" assigned to the assignee of the present invention.

The Twist locks are constructed according to Internationa Standards Organization requirements and are located at eac corner of the frame. They are actuated from the operator's ca where green and red lights on the control console indicate the status of lock engagement with the container.

The lift frame is also capable of being hydraulically side shifted and turned or slewed relative to the lift truck by means of hydraulic cylinders actuated by the hydraulic circuit of the lift truck, however, in order to achieve the productivity gains sought that the maneuvering of the lift frame will allow, it is necessary for the operator to have adequate visibility of the twist locks and without also moving the lift truck, for rapid engagement with the corner fittings of the container in securing it to the lift frame.

The lift truck will have a hydraulically elevatable mast or upright often be used with other attachments, such as forks, and for such purpose it is necessary to locate the operator's cab forward, close to the upright, for adequate visibility of the forktips in picking up loose loads or pallets. The optimum cab position for fork visibility is not the same as for maneuvering the lift frame when handling containers.

The lift truck will also have a structure, integral with the frame, overhanging the cab to protect the operator from falling loads, an overhead guard, the structural strength of which will meet or exceed the safety requirements of ANSI B56.1 and the Occupational Safety and Health Act, Subpart N Section 1910.178 for Powered Industrial Trucks. The overhanging portion will usually be a grill of ribs leaving openings for visibility at lift heights necessary for stacking shipping containers, nevertheless it has a tendency to reduce visibility from withi the cab which has a window in the roof directly above th operator's station for the purpose of being able to see at suc heights. The visibility is further restricted by the fact tha the window is hard to keep clean beneath the overhead guard.

The lift truck frame will have massive side rail supporting a counterweight and steer axle at the rear, an engine, a drive axle housing at the front bolted to the frame having tandem gear reduction hubs, differential gearing and other drive line components placed within the housing and the upright or mast of the fork lift truck mounted on trunions at either end of the housing. Hydraulic cylinders are actuated from controls in the cab to back or forward tilt the upright on its trunion mountings to the axle housing.

It is also common for the upright of a heavy forklift truck, such as required for lifting containers having capacities which range up to eighty or even a hundred thousand pounds, to have a relatively massive upright structure. The upright will have parallel outer rails secured on trunions to the axle and within which a moveable inner rail section that telescopes within the outer rails when raised and lowered on rollers by a hydraulic cylinder. Chains anchored to a cross-member between the outer rails travel over sheaves at the top of the inner rail section and extend down the other side fastening on to a carriage which travels on rollers mounted on the inner rail section. The forks or other attachment are mounted on the carriage. When the truck is used for lifting containers, the forks are taken off and a gooseneck is attached to the carriage from which the lift grame is suspended on chains for converting the lift truck into a container handler. The upright inner rail section is typically the same length as the outer rails to achieve maximum overlap of the roller sets in lifting the heavy loads. This creates a thicker rail cross-section when the upright is collapsed around which the operator must see in spotting containers on the tarmac.

It is common to exhaust the engine through a stack pipe directly behind the operator's cab which has a tendency to allow exhaust gases to be ejected over the top of the cab and to the rear which not only raises emission levels in the cab area, but also is a source of noise in the cab.

Tne hydraulic system of the lift truck will ordinarily have a pump for the upright lift and tile cylinder driven off a torqued converter from the engine, however lifting speeds adequate for heights usually found suitable for lift truck loads do not achieve the speeds desirable in container handling applications where thirty and forty-foot lifts are common.

Summary of the Invention

The present invention provides a self-propelled, counterbalanced, load handling vehicle especially a container transport, which has several unique advantages over the type of container handler described above in the background of the invention. The container transporter of the invention has a frame comprised of parallel side rail members having a counterweight frame portion at the rear and an integral fabricated axle housing at the front, the ends of which are fabricated with bracket arms for supporting the upright. A tower structure supports a cab establishing an operator's position elevated relative to the ground so that the operator has visibility in the transport position beneath the standard shipping container, or when elevated on the upright to a height in readiness for stacking, or setting on the ground such that the operator's line of sight is unobstructed and optimized for container handling.

The invention is capable of a number of different embodiments, but in essence is a self-propelled container transporter specifically designed for container transporting, stacking and spotting, a reference to setting containers down on precise lines on the tarmac of a container yard or transport terminal.

The operator's position is preferably behind the center of the frame which removes him from the vicinity of the upright and avoids having to provide an overhead guard for protection against falling objects.

More particularly, the operator's vision from the cab is unobstructed by any overhead guard and by that fact alone has improved visibility when stacking containers above eye level.

In addition, in accordance with the invention, the front cab window wraps around the operator's station and slopes to the rear, extending from above to below the operator's line of: sight for wide angle horizontal and vertical visibility.

The advantages of the wide angle window further being in that the window is composed of polyhedron panels sealed with narrow seams presenting a substantially continuous window area uninterrupted by vertical ribs or window frames.

Coupled with this advantage is the fact that a roof window in the cab is not required, such as in the prior art lift truck cab, which is difficult to keep clean, since the inclined surfaces of the invention are easily cleaned by wipers due to the inclination of the surface which does not hold dirt and grime to the same extent as the horizontal cab windows in the roof. The invention lies not just in the cab but in the total arrangement of the vehicle including the frame, the structure of which permits visibility from the operator's station out through the rear window of the cab and over the back of the counterweight to a position on the ground much closer to the rear of the transporter than would otherwise be the case if the cab were at a more forwardly location.

The frame also has as one of its unique advantages, in terms of a container transporter, that the upright is pivoted to bracket arms fabricated at the ends of the side rail members of the frame which allows for reducing the track width of the drive axle facilitating better positioning of a container between positioning marks on the tarmac.

In addition the frame is provided with a cross-member fabrication between the side rail members providing a housing for the drive axle components, hence avoiding the cost and additional weight of a separate drive axle housing.

The arrangement of the frame fabrications allow the body panel at the forward end to be recessed for better visibility from the operator's station over the drive axle housing.

In addition the inner rail of the upright terminates above the lower end of the outer rail enhancing visibility between the upright when traveling empty or spotting containers on the tarmac, and the outer rails are extended by an equal amount to permit sufficient overlap when the inner rail section is elevated to maximum height to provide sufficient roller bearing contact and minimize deflection while improving visibility through the upright in the raised transport position.

A further advantage of the invention is that the hydraulic circuit for raising and lowering the upright includes interdependent auxiliary circuits which automatically sense the engine speed and lift circuit pressure to match the engine torque with the load and achieve optimum lift speed.

It is also a feature of the invention that the exhaust gases from the engine are not diverted through a stack behind the operator's compartment, but rather are carried forwardly from the exhaust manifold through piping to an opening in the outer rail of the upright which has been formed partly as an elongated tube allowing the exhaust gases to vent through the top of the outer rail reducing exhaust gases in the vicinity of the cab and at the same time the engine noise level reaching the operator's ear.

Accordingly, it is a chief object of the invention to provide a highly maneuverable, self-propelled, rear steered, counterbalanced vehicle for stacking, spotting or transporting shipping containers in a more efficient and productive manner achieved primarily through improving the visibility from the operator's station through and around the upright or mast of the vehicle permitting the operator to observe the edges and corners of the container and lift frame thereby reducing side shifting or slewing of the lift frame to more accurately and rapidly position the twist locks in the container receptacles.

It is a further object of the invention to provide a container transporter having improved visibility through the upright and also to the rear for avoiding hazards or collision with objects in the path of the transporter when moving without a container and with the lift frame and upright fully lowered;

Another object of the invention is to provide a container handler vehicle having a frame fabricated with an integral drive axle housing and upright bracket, permitting an arrangement to not only improve visibility but reduce the cost and weight; A still further object of the present invention is to provide a container handler frame, having parallel side members structurally tied together at the front by a cross-member serving the duel purpose of housing the drive axle for the vehicle as well as mounting the upright in a pivotal fashion inside the track of the drive hubs sufficiently to narrow the track width of the vehicle and increase of visibility for positioning containers;

It is still another object of the invention to provide a frame having a tower structure for supporting a cab behind the frame center position from which position the angle of site from the operator's station in the cab ranges from a standard ISO four high shipping container stack to ground level through the front windows of the cab which can be easily wiped clean for continuous clear visibility;

It is another object of the invention to provide a upright or mast the inner rail section of which is shorter than the outer rails to improve the visibility through the upright, especially in the fully lowered position;

A further object of the present invention is to provide that the front end of the vehicle body is recesses behind the drive axle housing to improve the line of sight from the operator's station over the axle housing to aid in spotting containers or in avoiding objects in its path;

A further object of the invention is to provide a body structure providing ease of access to the cab by means of stairways constructed on opposite sides of the transporter leading to a deck surrounding the cab providing entry to the cab from either side of the machine assisted by hand rails for reaching or alighting from the deck area; A still further object of the invention is to provide that the cab structure can pivot out of the way for access to the engine compartment;

Another object of the present invention is to provide that the engine exhaust gases are piped forwardly to an outer rail of the upright which is closed throughout its length permitting the exhaust gases to vent through the top of the outer rail of the upright and reduce noise and pollution in the cab area;

Still another object of the invention is to provide a hydraulic lift circuit that matches engine speed and torque to the load to optimize the productivity by increasing the lift speed at light or empty container conditions; and

Still other objects of the present invention will become more apparent to those skilled in the art from the following description wherein there is shown and described a preferred embodiment of the invention by way of illustration of one of the modes best suited for carrying out the invention, however it can be appreciated that the invention is capable of other forms or modifications without materially departing from the scope thereof and it is understood that the following drawings and descriptions are to be regarded as illustrative and not restrictive in any manner of the scope of the invention.

DESCRIPTION OF THE FIGURES Figure 1 is a right side elevational view of the container transporter showing the upright, carriage pick-up and lift frame in the lowered position, the cab being shown in the normal operating position, and in a dotted line, folded back service position over the counterweight for access to the engine compartment?

Figure 2 is a partial plan view of the cab and counterweight area of Figure 1;

Figure 3 is a left side elevational view of the transporter as depicted in Figure 1 with the upright tilted back;

Figure 4 is a front elevational view of the transporter depicted in Figures 1-3 showing the carriage pick-up with the lift frame suspended therefrom partially broken away;

Figure 5 is a right side view of the transporter frame showing the counterweight frame area at the rear, the tower structure for supporting the cab and the axle housing and upright mounting at the front.

Figure 6 is a plan view of the frame depicted in Figure 5;

Figure 7 is a side elevational view showing the upright extended to full height depicting the visibility vertically and horizontally in a stacking operation and to the rear for backing up;

Figure 8 shows the upright partially extended for visibility through the upright and beneath a container being moved in the transport mode; and

Figure 9 shows a hydraulic lift circuit for sensing loads or engine speed to match lift speed with the load.

DETAILED DESCRIPTION OF THE INVENTION Referring now to Figure 1 in a preferred embodiment of the invention there is shown a container transporter vehicle having a body 10 supported on rear wheels 11 from which the vehicle is steered and drive wheels 12 from which it is propelled in either forward or reverse. The body 10 has a deck 13 reached by stairways 14 and 15 (Figures 2 and 3) on either side of the vehicle for accessing an operator's cab 16. Mounting o dismounting from the deck 13 is assisted by handrails 17 an

18. The cab may be entered through doors 20 on opposite sides o the cab to reach an operator's station having a seat (not shown) facing a console with control levers and gauges situated in the cab for maximum forward or reverse visibility.

It is a unique feature of the present invention that the cab is constructed with a wide angle, wraparound front window 22 that extends from one side of the operator's station to the other

(Figure 2) inclined to the rear such that front panels 23, 24, 25 are at such an angle with the vertical so as to permit the range of vision from the operator's station to above the height of a four high of ISO stack containers (Figure 7) and extending below the operator's station to permit a line of sight at the front of the vehicle where containers would be spotted on the tarmac.

Right and left panels 23 and 25 form a narrow seam with the center panel 24 without the assistance of any frame or divider other than a very narrow rubberized seal creating a more or less continuous horizontal expanse of window area across the front and partially on either side of the operator's station for viewing the lift frame when fully extended or collapsed.

At the front of the transporter body 26 is an upright or mast structure 29 having a movable inner rail section 30 which can be hydraulically extended upwardly on roller sets from parallel outer fixed rails 31 by means of a hydraulic cylinder

34, which lifts against a cross-member 36, having a chain sheave

37, over which travels a chain 38, fastened at one end to a carriage pick-up 40, traveling on rollers (not shown) on the inner rail section 30, and fastened at the other end to chain anchors (not shown) in cross member 36. The cross member 41 SHEET spans across the back of the outer rails providing late strength. By extending the hydraulic cylinder 34, the inner ra section 30 is elevated, reaching its maximum lift height (Fig. for stacking containers four high. The carriage pick-up supports a pick-up frame structure 42, (Figure 4) from which suspended a lift frame 44 by chains 45. Twist locks 48 at t corners of the telescoping ends of the lift frame are broug into engagement with locking receptacles 50 (Figure 7-8) in t upper corners of the container 52, allowing it to be lifted a transported; the transport position is depicted in Fig. 8. T lift frame 44 can be laterally extended by telescoping out t ends in opposite directions to align the twist locks 48 above t container locking receptacles 50 for either twenty of forty fo long containers.

A counterweight 60 mounted at the rear of the transport partially counterbalances the load of a container 52 being lifte at the front by the upright which can be tilted forwards o backwards (Figure 3) from vertical as required by a pair o hydraulic tilt cylinders 49. An engine 54, shown in dotted line in Figure 3, has an exhaust pipe 55 the front end of which enter an opening 56 in the outer rail 31 which is closed off throughou its length to form a tube 57 exhausting engine gases out th upper end 58 and away from the cab 16.

Referring to Figures 5 and 6, the transporter frame 62 ha a rear counterweight frame portion 64 on which the counterweigh

60 is mounted by means of a bracket 65 and a tower structure 6 behind the medial point of the frame 62 for supporting the ca structure 16 in a pivotal manner allowing the cab to be swun rearwardly for servicing the engine 54 (Figure 1) and pivotall supporting at 63 the pair of tilt cylinder 49. The frame 62 i comprised of two parallel side rail members 69, 70 which are structurally interconnected at the front by cross-member 72, fabricated as a structural member for the frame but also as an axle housing having hub plates 73, one at each end, for mounting gear reduction planetary hubs (not shown) driven from a differential housed in a belled-out portion 74 of the housing

72. Engine 54 has a coupled torque converted for driving the wheels 12 and propelling the unit. The gear reduction planetary hubs on which the wheels 12 are mounted are driven by axle shafts passing through openings 83 in the ends of the hub plates 73.

Fabricated at the ends of each frame rail 69, 70 are upright bracket arms 80, which pivotally support at 82 the lower ends of the upright outer rails 31.

As best shown in Fig. 4, the track width of the wheels 12 is narrower because of the fabricated upright bracket arm being on the frame rails allowing the wheels to be closer. This provides greater visibility since the wheels do not obscure the ends of the containers when spotting. Also, the inner rails 30 are tied together at their lower ends by cross-member 90, which in the lowered position of the upright terminates above the lower ends of the outer rails 31. However, to provide maximum lift and allow sufficient roller overlap for stability of the upright when fully extended (Fig. 7), the outer rails 31 are longer by this amount, the overall effect being to reduce the cross sectional thickness of the upright in the lowered position (dotted line position in Figure 7), thereby opening up a line of sight from the operator's station between the outer rails 31 and below the cross member 90. In this connection, it is also noted that the body 26 is recessed at the front 94 behind the bell housing 74 to provide even greater visibility from the cab over the bell housing through the upright and out to a distance in front of th machine sufficient to enable the operator to accurately an rapidly spot a container on a predetermined line on the tarmac.

In operation, the container transporter will pick up, transport, stack or spot containers 52 to a stack height of fou standard ISO containers as depicted in Figure 7. Hence, the operator's line of sight from the operator's station in the cab

16 will range from a line 95 observing the locking receptacles 50 of the container 52 being picked up or deposited onto a stack

(shown in dotted lines) setting on the tarmac. The operator also has a view along the line 96 of the opposite corner of the container 52 being manipulated, and looking downwardly along line

97 to the front corner of the tarmac, he can place a first container accurately along the spotting lines drawn on the tarmac•

Additionally, the operator has a clear view out the back along line of sight 98 and can observe, before backing up, whether there are any objects or other hazards to operate the machine in reverse.

Additionally, the operator has (as shown in Figure 8) a view through the upright beneath the container 52 while transporting it as shown by the line of sight 99 below the partially raised inner rails 30.

As shown in figure 9, a portion of the hydraulic circuit is depicted where three gear pumps 100, 102, 103 are driven off the torque converter at engine speed each having an independent circuit for functional applications required in operation of the container handler including a steering circuit 105 served by pump

100, a lifting circuit 107 connected to the pump 102 and a brake circuit 108 served be pump 103, however circuits 105. and 108 are also interdependent with lift circuit 107 to allow all thr pumps to be connected to the lift circuit depending upon t sensing of engine speed or the weight of a load being lifted the upright. The steering circuit 105 includes a steering val

112 connected to the pump 100 by hydraulic line 113 the output which is directed to a steering cylinder, represented by t block 114, mounted at the rear between the frame and steer ax for steering the transporter in a known manner. Hydraulic lin

115 and 116 connect the steering valve 112 to the steeri cylinder. Line 120 also connect the output of pump 100 to t lift circuit. The lift circuit 107 connects the output of pu

102 to the hydraulic cylinder 34 through line 118 for raising a lowering the upright 29. A diverter valve 127 senses engi speed and at 1800 rpm shifts to combine the output of pump 1 with that of pumps 100 and 102 in line 118 to achieve the highe lift speed when the engine can operate at high rpms and lo torque output because of handling light loads or emp containers. Another diverter valve 125 operates according differential pressure sensed because of check valve 117 betwe ends 120 and 119 and when the differential pressure exceeds 15 psi, valve 125 diverts the output of pump 100 to reservoir 1 and because of low engine speeds valve 127 also diverts t output of pump 103 to reservoir 129, such that when the loadi conditions exceed both the differential pressure setting a engine speed setting, the torque output is maximized prioritized for the lift circuit 107 and pumps 100 and 103 a diverted out of the system and only pump 102 is connected to th lift circuit conserving the engine torque for lifting at l speed maximum load conditions. However, for light loads at hig engine speed low torque requirements the diverter valve 125, 12 both are shifted in the direction to deliver the output of pump

100,103 through line 118 to the lift cylinder 34 to provid maximum fluid flow to the lift circuit achieving higher speeds o lift than would otherwise be possible without overloading th engine.

Thus, it will be increasingly apparent that th productivity of the container transporter is greatly augmented a visualized in Figure 7 when approaching a 4-high stack o containers approximately 40 feet in height with the object of picking up the top most container. The operator will want to achieve maximum lift speed to reach this height as quickly as possible and since the lift frame is not carrying any container, the engine can operate at maximum rpm. Both diverter valves 125,

127 will be shifted to direct the output of pumps 100 and 104 to the lift circuit and combine their outputs with pump 102 to achieve the maximum lift speeds.

On the other hand, if the container being lifted by the lift frame is at rated capacity of the container handler, the maximum engine torque will be required for operating pump 102 and at the lower engine speed, and high differential pressure valves

125, 127 will divert the output of both pumps 100 and 103 to reservoirs 129, 130 such that the maximum torque of the engine is committed to operating pump 102 thus matching the load with the engine torque.

Also, for intermediate loads one or the other valve 125,

127 will be shifted to divert the output of either pump 100 or

103 as conditions require, to change the lift speed according to engine speed or pressure differential conditions, such that the lift speed is more nearly matched to the engine torque output and weight of the load to achieve the optimum lift speed under those given conditions.

For those skilled in the art, it will be kept in mind tha various changes or modifications in the structure, components o relative arrangement of parts may be made without departing fro the scope of the invention which is claimed as follows:

We claim:

1. A container transporter vehicle having a frame, a counterweight at the rear of the frame, an elevating upright and pick-up frame at the front for lifting and transporting containers, the improvement comprising; a tower structure projecting upwardly from the frame spaced rearwardly from the upright a substantial distance along the length of the frame, a cab containing an operator's station mounted on the tower structure, the front surface of the cab providing a wide angle window area inclined toward the rear affording a range of vision from the operator's station horizontally and vertically to facilitate the handling of containers.

2. The container transporter vehicle as defined in claim 1 wherein the tower structure is located to the rear of center on the frame.

3. The container transporter vehicle as defined in claim 1 wherein the window area wraps around the front of the operator's station to afford an unobstructed horizontal range of vision to the maximum width of standard ISO containers.

4. A container transporter vehicle as defined in claim 1 wherein the frame has a pair of side rail members, a cross member located adjacent the front structurally connecting the side rail numbers, and providing a housing for drive elements of a drive axle for propelling the vehicle whereby the vehicle chassis has a lower silhouette for better visibility from the operator's

Claims

station over the axle housing.

5. A container transporter vehicle as defined in claim where the frame side rail numbers each have bracket arms integral therewith to force, a pair of lower pivots for the upright and means extending between the tower structure and upright for tilting it orwardly or rearwardly from a vertical position, the mounting location of the upright affording a narrower track width for the drive axle to improve visibility in spotting containers.

6. A container transporter vehicle as defined in claim 5 wherein the upright has an inner parallel rail section, a parallel outer rail section for telescopically mounting the inner rail section, a hydraulic cylinder connected between the outer and inner rail sections for elevating the inner rail section, the bracket arms projecting forwardly and downwardly for mounting the outer rail section in a lower plane than that of the axle housing.

7. A container transporter vehicle as defined in claim 6 having an engine, an outer rail of the upright being closed off throughout its length, open at the top, to provide a tubular passage, means connecting the engine exhaust to the tubular passage so that exhaust gases are vented out through the top of the rail thereby minimizing noise and exhaust levels in the cab.

8. A container transporter vehicle as defined in claim 6 wherein the inner rail section terminates at the lower end above the bottom of the outer rail section to reduce the cross sectional thickness of the upright at the lowered position of the inner rail section.

9. A container transporter handling vehicle having a frame, a counterweight at the rear of the frame, and elevating upright at the front having parallel outer rails pivoted to the frame, parallel inner rails mounted on rollers extensible upwardly from the outer rails for lifting and transporting containers, the improvement comprising a hydraulic circuit, a hydraulic cylinder connected between the outer and inner rails for first and second pumps driven by the engine, output of the first pump connected to the hydraulic cylinder, output of the second pump connected normally to a separate function for operating the vehicle, and value means for measuring the difference in pressure between the hydraulic cylinder and said separate function for diverting the output of the second pump to augment that of the first when the pressure differential exceeds a predetermined setting whereby the lift speed of the upright is increased.

10. The container transporter as defined in claim 9 wherein a third pump is driven by the engine, a third hydraulic circuit connects the third pump to operate a separate function of the vehicle, a value means sensing the speed of the engine for diverting the output of the third pump to the hydraulic circuit when the engine speed exceeds a predetermined setting for further increasing the lift speed.

11. A container transporter vehicle having a frame, a counterweight at the rear of the frame, am elevating structure at the front of the frame, a lift frame of rectangular configuration lifted by the elevating structure, twist locks at each corner of the lift frame for attaching the lift frame to ISO shipping containers, the improvement comprisiag a tower structure projecting upwardly from the frame, a cab containing an operator's station mounted on the tower structure, the front of the cab inclined rearwardly and providing a wide viewing area from the operator's station affording a range of vision immediately in front of the vehicle to the maximum lift height o the lift frame.

12. The container transporter vehicle as defined in clai 11 wherein the tower structure is to the rear of the center o the frame and elevates the operator's station such that at ey level a horizontal range of vision is provided beneath container lifted to a transport position.

13. The container transporter vehicle as defined in clai 11 wherein the front of the cab wraps substantially around the front of the operator's station to provide a wide horizontal viewing angle.

14. container transporter vehicle as defined in claim 11 wherein the frame as parallel side rails, a cross member connected adjacent to the front providing structural support for the side rail members, said cross member being fabricated as a hollow- structure providing an integral axle housing, axle hubs mounted at opposite ends of the housing for mounting tires to propel the vehicle.

15. A container transporter vehicle as defined in claim 11 where the elevating structure comprises a pair of outer rails within which a pair of inner rails are extended, the frame comprising a pair of brackets projecting forwardly of the cross member terminating in a pair of pivotal mountings, the outer rails mounted on said pivotal mountings, the inner rails having an overlap with the outer rails when fully collapsed that is reduced in length to provide a greater viewing area between the outer rails, and the outer rails being extended at the upper end by substantially the same amount as the inner rails are reduced in length to compensate for the reduced overlap to provide stiffness in the fully extended position of the upright. 16. The container transporter vehicle as defined in claim

11 wherein the front of the cab is comprised of panel sections, a first panel transversed to the center line of the vehicle, a second panel obliquely connected to the first panel on one side, a third panel obliquely connected to the first panel on the other side, the angle between the first and second and first and third panels being such os as to align the panels at right angles to the view from the operator's station with respect to twist locks of the lift frame.

17. The container transporter vehicle as defined in claim 11 wherein the cab elevates the operator's station relative to the counterweight in the rear so as to be able to see the ground adjacent the rear of the vehicle.