GB2059904A

GB2059904A - A cab for a crane

Info

Publication number: GB2059904A
Application number: GB8032171A
Authority: GB
Original assignee: Mannesmann Demag AG
Current assignee: Mannesmann Demag AG
Priority date: 1979-10-06
Filing date: 1980-10-06
Publication date: 1981-04-29
Also published as: IT8025128A0; FR2467168B3; IT1133164B; FR2467168A1; GB2059904B; SE8006877L

Abstract

A cab is supported from a crane by springs 19 and vibration dampers 20. Fixed windows, such as 14, may be cleaned from within the cab by opening windows 12 and 13. A window 17 in the bottom of the cab may be opened after raising a grid 16. A seat 1 for the operator is rotatable on a pillar 4 and has adjustable elbow rests 3. Cupboard space is provided to receive items of equipment and includes a built-in container for water used in cleaning the windows. <IMAGE>

Description

SPECIFICATION A cab for a crane The conventional cab of a crane does not permit the crane driver to work without tiring throughout his entire shift. The drivers seat is rigidly installed and the controls are fitted to the side walls of the cab. When he looks downwards, the driver must adopt a posture in which his back muscles are strained and, in this position, the driver must keep his arm at an angle to his body in order to operate the controls. In general, the seat is oriented in line with the crane bridge so that when the crane is travelling, the driver must turn his head to look in the direction of travel. This force posture greatly taxes the driver and causes him to tire prematurely. His performance and alertness may also be impaired by inadequate air conditioning and ventilation.

Conventionally, the cab is provided with plate glass windows which cannot be cleaned other than by using a ladder to climb to the level of the cab. As a result, the windows are cleaned only when they have become extremely dirty, so that for much of the time visibility for the driver is poor. Visibility is further impaired by the driver leaving his personal belongings within the cab because of the lack of any storage space for them.

The working conditions of the driver are also made uncomfortable because of vibrations occuring during the travel of the crane and the cab, and also as the load is lifted and deposited. These vibrations often lie in the frequency range below 5Hz and reduce the performance of the crane driver and may even damage his health.

These problems are avoided by the cab which will now be described. This cab is particularly intended for use with a travelling bridge crane, so as to be mounted on a crab movable along the bridge, or so as to be fixed to the bridge itself. To enable the driver to look in any desired direction without placing on him a physical strain, the seat is rotatable and has the crance controls arranged beside it. Consequently, the driver can turn the seat to face in the direction of the crane bridge when lifting or lowering a load, or in the direction of travel of the crane during transportation of the load. Because the control or controls turn with the seat, the driver need not adopt a strained posture, so that inaccuracies in the control of the crane is prevented.

At least one wall of the cab is provided with one or more fitted cupboards in which tools and equipment, together with the drivers personal belongings may be stowed, so that they do not obstruct visibility to the sides and downwards.

A fitting for the cab conveniently within a compartment of a cupboard may take the form of a water container dimensioned to receive a device for cleaning the window and including a sponge and rubber drying lip. The cab includes windows which may be opened to enable the cleaning device, mounted on a handle, to be used to clean the outside surfaces of all of the windows. By arranging the windows in this way and providing within the cab a supply of water and a device for cleaniny the windows, the crane driver is unlikely to wait until visibility is badly obscured before cleaning the windows.

Advantageously, one wall of the water container is flush with and forms part of the internal panelling of the cab when the container is stowed. The lower edge of this wall of the container may project and be received in a slot in the floor of the cab so as to allow the container to tilt through a small angle into an inclined position in which it is retained.

The upper part of the water container may be provided with a simple seal. Beside providing cupboard space for the personal belongings of the driver, compartments may be provided for a fire extinguisher, torch, waste bin, radio, reading lamp, heater, light, intercom, and electric socket for example. A folding table and a folding seat for a co-driver may also be provided, hinged to a wall or the door. Within the roof there may be provided a compartment for an escape device, conveniently in the form of a rope ladder which, upon release, drops through an opening in the floor revealed by raising a window in the bottom of the cab. This window may be covered by a hinged grating which, when raised, releases a spring to automatically raise the window.By supporting the rope ladder, or other escape device, from a point adjacent the roof, it extends through the cab and can easily be mounted by the driver in an emergency, without the risk which would be experienced if the rope ladder were fixed to a trap door in the floor.

In order to provide the cab with adequate ventilation, an air circulating or air-conditioning unit can be provided, conveniently in the cupboard space provided in the rear wall. This unit may have an air outlet arranged beneath the roof so as to direct a flow of air along the underside of the roof, down the inner side of the front window and across the floor to an intake. In this way, the convection of heat into the cab from the front window is reduced.

Likewise, the amount of heat and light entering the cab from the sides may be reduced by providing roller blinds which, when provided in the form of fitted unit, provide no form of obstruction.

As mentioned above, cleaning of the windows is facilitated by providing windows which can be opened. Each of the lateral sides of the cab may have a wide, fixed window and a narrow opening window extending substantially the full height of the cab. Conveniently, the fixed window is located forwardly of the opening window, which is provided with some form of stay to prevent it opening sufficiently far for the driver to fall through.

The window can, however, be opened sufficiently for him to stretch out his arm in order to clean the fixed window. The out side of the opening window can also be cleaned by the driver stretching a hand through the opening and holding the cleaning device with the hand bent. The front side of the cab may have a large fixed window surmounted by an opening window which is hinged at its upper edge and opens inwards. The fixed window can be cleaned by the driver leaning through the space above it, and the opening window can be cleaned from within the cab. The window in the bottom of the cab folds upwards, as mentioned above, so that both sides can be cleaned easily.The window or windows arranged in the bottom of the cab and covered by one or more gratings, extend from the front side of the cab to near the foot of the seat, as well as the length of one of the side walls, so permitting maximum visibility downwards. Spring elements may be provided to hold the various opening windows in their open positions.

The entrance door to the cab is provided in the rear side adjacent the fitted cupboards.

Outside the door, the cab is provided with a platform which can be reached by way of a ladder leading to the upper side of the crane, so allowing the driver to gain access more conveniently than by way of the conventional trap door in the roof, which can only be entered with extreme caution.

The seat provided for the crane driver has elbow supports which can be adjusted to correspond to his size and to the inclination of his body when he leans forward to look downwards. During operation of the crane, his hand may rest easily on the controls, his elbow being supported comfortably by the elbow support. These supports have the advantage over conventional arm rests that they allow the hand freedom of movement needed for driving the crane. Support for the forearm is unnecessary since the hand rests on the operating controls.

Each of the elbow supports may be provided with guides to permit its adjustment in position. The guide may take the form of a support rod rigid with the elbow support and curved about an axis located at the zero postion of the operating element. This arrangement is particularly advantageous in the event that the driver must operate the crane while bent forward for prolonged periods of time, as the elbow is raised with the operating element as its pivot.

If the crane is of the type in which the cab is fixed on the crab or trolly, and in other cases, the driver has to observe the crane hook which is located beneath his point of observation. In order to do this, he has to bend forwards to a considerable extent, greatly straining his back muscles. Accordingly, shoulder retaining straps are provided on the back rests in order to support him in this position and relax the back muscles. The straps may be connected to rods which are guided in the backrest in the manner conventional in headrests. Each rod may have two rows of depressions, any of which may be engaged by a detent. The shoulder retaining straps serve to hold the forwardly bent trunk about 30 centimeters in front of the back rests.

The walls of the cab may be completely or partially thermally insulated, and the windows made from insulating glass. To minimise the vibration applied to the cab, it is supported by means of at least one supporting spring element and at least two substantially horizontally arranged vibration dampers. Preferably, there are three spring elements arranged at the maximum possible distance from each other in order to supress swinging o: the cab as the crane starts and stops. The cab ic effectively insulated from vibration if the spring elements are flexible in design with inherent frequencies of about 1 Hz. In this way, vibrations which humans find unpleasant are converted into tolerable movements, and the cab behaves iike a damped multi-element pendulum.

The vibration dampers and spring elements may have frictionless articulations at their ends which may be designed, for example as spherical heads or rubber articulations and permit movement of the cab in all three coordinates. Each spring element may taka the form of a piston and cylinder unit connected to a hydraulic accumulator which is connected to a level-regulating hydraulic s up- ply unit. A throttle element may be provided to permit the adjustment of optimum proper ties of absorbtion, and can be arranged in a connecting line between the piston and cylinder unit and the accumulator. The level regulator compensates for variations in load, for example when an instructor enters the cab, as well as for impermissibly high static spring travel as well as losses caused by leakage.

The spring elements may also be steel springs, for example helical springs with additional hydraulic vibration dampers.

Alternatively, the horizontal vibration dampers can be hydraulic vibration dampers of the type normally used in motor vehicles, for example. Two horizontal vibration dampers are preferably arranged parallel to each other, approximately at the corners of the cab, and another horizontal vibration damper is arranged approximately in the axis to the centre of gravity of the cab and perpendicularly to the first-mentioned dampers. The horizontal vibration dampers supress translation of horizontal vibrations and rotary vibrations about the vertical axis of the cab. Brackets which extend approximately to the roof level of the cab are provided on the crane or the crab in order to support the horizontal vibration dampers. With this suspension arrangement, the usually conventional transverse spring elements are no longer needed.

In the Drawings: Figure 1 is a front elevation of the cab, Figure 2 is a section taken on the line ll-ll in Fig. 1, Figure 3 is a section taken on the line Ill-Ill in Fig. 1, Figure 4 is a view similar to that shown in Fig. 2 but to a larger scale, Figure 5 is a view similar to Fig. 4 but showing details of a seat for the crane driver, Figure 6 shows a detail from Fig. 5 to a still larger scale, Figure 7 is a diagrammatic view from the opposite side of the cab to show the suspension system thereof, Figure 8 is a view from above Fig. 7, Figure 9 is a view of a detail of the suspension system looking in the direction of arrow X in Fig. 7, and Figure 10 is a view looking in the direction of the arrow Y in Fig. 9.

Referring to Figs. 1 to 3, the cab of a crane has a floor 1 5 joined to a roof 1 8 by vertical frame members 10. The cab is suspended from the crane bridge girder (not shown in the drawings) by means of three C-shaped springs 1 9 fixed to the roof 1 8. One of the springs is arranged centrally of the forward edge of the roof 1 8 and the others are arranged near respective ends of the rearward edge and are provided with obliquely extending vibration dampers 20.

The vertical frame members 10 at the forward side of the cab are connected by horizontal frame members and support a fixed plate glass window 1 4 which occupies the major part of the forward side of the cab.

Arranged above the front window 14 is a window 13, the upper edge of which is hinged to permit it to be opened inwards as indicated in Fig. 2. Each of the sides of the cab has a vertical frame member located offcentre towards the rear of the cab, the space forwardly of this frame member being occupied by a plate glass side window 11. Located rearwardly of the window 11 in a window 1 2 which can be opened outwards to a limited extent.

The fixed floor 1 5 occupies only the unbroken rectangular space in the upper left part of Fig. 3. Forwardly of the floor is an inclined bottom window 1 7 which extends substantially the full width of the cab and is surmounted by a grid 16. Laterally of the floor 1 5 is a horizontal bottom window, likewise surmounted by a grid. Each of these grids is hinged at its edge remote from the floor so that it may be lifted into a substantially position against one of the fixed window, as indicated in Fig. 2 in respect of the grid 1 6.

Each of the bottom windows is hinged to the floor 1 5 so that, following opening of the associated grid, it may be lifted into a vertical position, likewise as indicated in Fig. 2 in the case of the window 17.

By arranging the windows of the cab as described above, it is possible for them to be cleaned easily and safely both inside and out, access to the outside of the window 1 4 being gained by opening the window 13, and access to the outsides of the windows 11 being gained through the gap obtained when the windows 1 2 are opened to the limited extent possible. The outside of the windows 1 2 may also be cleaned by way of this gap.

The rearward side of the cab is formed from a number of vertical frame members 10, between two of which is arranged a door 7 capable of being opened outwards and used to support a seat 24 for a co-driver, the seat 24 being raisable into a vertical stowed position. The remaining area of the rear side of the cab is occupied by cupboards 8, the side 9 of which facing inwardly of the cab incorporating the cupboard doors and forming a panelled surface.

Mounted on the floor 1 5 is a pillar or stand 4 for a sprung seat which is rotatable and adjustable in height.

Referring now to Fig. 4, the cupboard 8 includes various compartments including one with shelves 26 for the personal belongings of the crane driver. Other compartments are provided to contain various essential equipment, including a fire extingisher 25 arranged in an open niche and a water container 21. The container 21 is in the form of a rectangular moulding, the front surface of which forms part of the panelling 9. The lower edge 22 of the front surface is received in a slot 23 in the floor 15, and the upper edge of the cantainer includes a seal and a moulded handle to permit the container to be tilted forwards into the inclined position shown in broken lines in which the container is retained by cooperation of edge 22 in the slot 23. A magnetic coupling or other device may serve to hold the container in its normally closed upright position concealed within the cupboard space.

Associated with the container is a window cleaning device having an elongate handle, sponge pad and wiper blade. A lower portion of the panelling 9 may be formed by the leaf of a folding table 27 which may be raised into the horizontal position indicated when it may be used by the crane driver after swiveling his seat into a rearward facing position.

Arranged in one of the upper rearward corners of the cab is a loudspeaker 28 and a lamp, not shown. Arranged centrally of the upper wall 6 immediately beneath the roof 1 8 is a discharge opening 29 of an air conditioning unit for directing an airstream along the underside of the roof and down the front wall, utilising the Koanda effect, to air inlet openings on the floor, the path of the air stream being indicated by broken lines in Fig. 5. In this way, the driver is protected from heat radiated from the windows at the front of the cab. Shielding from heat and light entering the cab from the sides may be provided by roller blinds 43 fixed above the side windows in the interior of the roof 1 8. Also arranged in the roof space in the v cinity of the forward side of the cab is a hatch 31 concealing a rope ladder 30.The rope ladder is held in its cavity or cupboard by a loop (not shown) and is so arranged that, it will upon release, fall through an opening provided by raising the grating 1 6 and bottom window 1 7. Because the ladder extends the full height of the cab, the crane driver may climb onto it safely and without difficulty.

The crane drivers seat is shown in more detail in Fig. 5 and has a reclining backrest 2, and adjustable elbow supports 3 to enable the operator to handle comfortably the crane controls 5 in the form of levers pivoted to panels at the sides of the seats.

Each elbow support 3 is mounted on a curved support rod 32 received in a guide 34 rigid with the seat, to permit the elbow support to be raised along a curved path centred on the control device 5 so as to provide comfortable support for the arms of the driver when he is in either the erect of bent forwards position shown. A set screw 33 may be released and re-tightened during adustment of the elbow support. Support for the drivers back when he is in the bent forward position is provided by shoulder retaining straps 37 connected to the rods 35 received in guides 36. The arrangement of one of the rods and its guide is shown in Fig. 6. Extending from the guide is a tube 41 which receives a detent 38 urged towards the rod 35 by a spring 39, the pressure in which is adjusted by a cap nut 42 screwed onto the end of the tube.The rod may be held in position by engaging the detent with a selected depression 40, there being two rows of such depressions to permit the rod to be turned sideways between two angular positions separated by 90 degrees.

An alternative suspension system for the cab is shown in Figs. 7 to 10. In this arrangement the cab, having a centre of gravity S is suspended from a crab 48 by resilient suspension elements 1 9 in the manner of a multifilament pendulum. The crab, indicated in chain lines, is itself supported from the bridge of the crane, not shown. Horizontal vibration dampers 20a and 20b bear against brackets 48a and 48b of the crab, the dampers 20a being arranged at right angles to the dampers 20b.

The suspension elements 1 9 and the vibration dampers 20 have articulations 44 at their ends. Each of the suspension elements takes the form of a piston and cylinder unit connected by way of a line 46 and throttle 47 with a hydraulic accumulator 45. The accumulators are connected by way of pressure lines (not shown) to a control pressue supply unit which adjusts the height of the cab in response to exceptional loading and is controlled by displacement transducers connected to the individual piston and cylinder units.

Support members 49 and angle pieces 50 extend from the roof of the cab to the springs and vibration dampers and are thus easily accessible next to the cab.

Claims

1. The cab of a crane comprising a floor, roof and sides extending between the floor and the roof, one of said sides being provided with fitted wall cupboards, a seat supported upon the floor for rotation, and operating controls arranged upon one side of the seal at least

2. A cab according to claim 1, fitted with a water container.

3. A cab according to claim 2, wherein one surface of the water container forms internal panelling of the cab and has its lower edge engaged in a slot permitting the container to tilt forwardly through a limited angle, and the top of the container is provided with a seal.

4. A cab according to any preceding claim, wherein the fitted cupboard includes a compartment for personal belongings of the crane driver.

5. A cab according to any preceding claim, including a folding table hinged to one wall of the cab.

6. A cab according to any preceding claim, wherein an access door to the cab has hinged thereto a seat for a co-driver.

7. A cab according to any preceding claim, including a compartment within the roof for an emergency escape device, for example in the form of a rope ladder, said device being arranged above a window capable of being opened in the bottom of the cab.

8. A cab according to any preceding claim, including a grid or grating covering a window in the bottom of the cab.

9. A cab according to claim 8, wherein the grating and window in the bottom of the cab are hinged at respective opposite edges to permit them to be raised.

10. A cab according to any preceding claim including an air conditioning unit including a discharge outlet arranged in the rearward part of the cab adjacent the roof, the outlet being directed towards the front of the cab.

11. A cab according to any preceding claim, including roller blinds for covering side windows of the cab.

1 2. A cab according to any preceding claim, wherein each lateral side of the cab has a fixed window and rearwardly thereof a nar row openable window to permit cleaning of the fixed window.

1 3. A cab according to any preceding claim, wherein the front side of the cab has a fixed window surmounted by an inwardly openable window.

14. A cab according to any preceding claim, wherein an access door is located adjacent the fitted cupboards, with a platform having a ladder leading through the upper edge of the crane in front of it.

1 5. A cab according to any preceding claim, wherein the seat is provided with adjustable elbow supports.

1 6. A cab according to claim 15, wherein each elbow support is provided with a support rod received in a guide, the guide being provided with screws for fixing the rod in an adjusted position.

1 7. A cab according to claim 16, wherein each supporting rod is arcuate and has a centre of curvature which coincides with the mean position of a control member.

18. A cab according to any preceding claim, wherein a reclining backrest of the seat has guides for rods connected with shoulder retaining straps.

1 9. A cab according to claim 18, including a detent mechanism for retaining each rod in a selected position.

20. A cab according to claim 19, including a two rows of depressions or apertures in the rod for co-operation with the detent mechanism.

21. A cab according to any preceding claim, wherein the cab is supported upon the crane by means of springs and vibration dampers.

22. A cab according to any preceding claim, the cab being supported from the crane or a crab by means of at least one spring and at least two substantially horizontal vibration dampers.

23. A cab according to claim 22, including at least three spring elements arranged at a maximum distance from one another.

24. A cab according to any of claims 21 to 23, wherein the spring elements and the horizontal vibration dampers have articulated heads.

25. A cab according to claim 24, wherein the articulated heads are frictionless articulated heads.

26. A cab according to any of claims 22 to 24, wherein each spring element is in the form of a piston and cylinder unit conected to a hydraulic accumulator.

27. A cab according to claim 26, wherein the hydraulic accumulator is connected to a level-regulating hydraulic supply unit.

28. A cab according to claim 26, wherein a throttle element is arranged in a connecting line between the piston and cylinder unit and hydraulic accumulator.

29. A cab according to claim 22 and 23, wherein each spring element is in the form of a steel spring, for example a helical spring with additional vibration dampers.

30. A cab according to claim 29, wherein the vibration dampers are hydraulic vibration dampers.

31. A cab according to claim 30, wherein two horizontal vibration dampers are arranged approximately at the corners of the cab parallel to each other and a third vibration damper is arranged approximately on the axis through the centre of gravity of the cab and approximately at right angles to the first-mentioned vibration dampers.

32. A cab according to claim 31, wherein brackets are provided on the crane or the crab to support the horizontal vibration dampers.

33. A cab for a crane substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

34. A cab of a crane comprising a box-like structure having windows at the forward and lateral sides, the windows at each side including a fixed window and an openable window, a portion of the underside of the cab being inclined upwardly towards the front side and having therein on operable window covered by a grating.

35. A cab of a crane comprising a box-like structure having in one side thereof a door, a storage structure being arranged adjacent the door, and a water container incorporated in the storage structure said container being pivotable between an upright stowed position and an inclined released position.

36. A cab a of crane having an emergency excape device mounted in or adjacent its roof, and a trap in the floor of the cab in line with said device.

37. A cab of a crane suspended by resilient suspension devices and damped vibrationally by vibration damper means.

38. A seat having elbow rests supported adjustably by arcuate rods received in complementary guides having an axis of curvature coinciding with a control device.