This invention concerns an arrangement at the drivers compartment at lifting trucks including a steering wheel for the controlling of the travel direction and different control means for the controlling of the lifting device of the truck.
Lifting Trucks are frequently used during long work shifts in an environment that is arduous for the driver through time strain, noise, cold, heat and high demands on accuracy etc. For industrial trucks intended for indoor material handling the complication is added that the driver normally sits in a driving seat directed perpendicularly in relation to the common longitudinal and traveling direction. In order to avoid load and wear injuries of the drivers great efforts have been made to improve the sitting position and the accessibility for different control means. Thus the steering wheel is frequently supported on a console that can be moved from or towards the driver and there are further different supports for arms and elbows. Hitherto known trucks however have stationary control means for the controlling of the lifting device etc while steering wheel and drivers seat normally are adjustable. This means that the localization of the control means must be done according to some chosen normal value while the steering wheel can be adjusted individually for each driver. The control means will therefor be placed too far away for a short driver and too close for a big one. This influences not only the ergonomics but also the driving safety in particular in situations where precision and swiftness is required.
From EP-A- 0 555 025 (applno. 93300680.1) a truck with pivoting arm rests is known. The operator travels up with the forks and their load gripping two control handles which also serve as support, particularly if the operator is standing up. Even if the armrests are pivotable the position of the operator will be very much the same at all times when manoeuvreing is executed. If the operator did not have considerable much of other activities (picking goods for instance) this would lead to worn muscles and joints. For this particular truck the handles are presumably very good also in a way securing that the operator has the right position when lifting and lowering himself. For other types of trucks that are driven around more like cars or where the driver always remain at the ground level the pivotable armrests with their manoeuvreing handles would instead lock a drivers position too much resulting in worn hands, arms and shoulders and also increased strain on the neck that would have to compensate the fixed body, for instance when looking up at a load.
One purpose of this invention is therefor to achieve an arrangement at drivers compartments for truck drivers, that is so built that the mentioned inconveniences can be avoided. Another object is to obtain a more efficient and more easily handled unit for the steering and controlling of the truck.
The above objects are achieved by an arrangement where the steering wheel and the control means are arranged on a common control panel and that this is carried by a movable arm that is adjustable in different positions for adaption to different drivers and that the control panel is an elongate body with an upper side and a lower side and that the steering wheel is mounted on the upper side of one end of the body.
Further objects and advantages with the invention are apparent from the following description.
The invention will now be described in greater detail with reference to the appended drawings on which:
Fig 1 shows a so called movable mast truck intended for indoor handling of palleted goods. The truck includes, as is usual, a chassis 11 and a lifting mast 12 mounted on the chassis 11 and in turn carrying a lifting device 13 in the shape of a lifting fork movable in a carriage along the mast. On the rear part of the truck a driving compartment in the shape of a drivers cabin 14 is arranged. This includes two lateral walls 15, 16, a front wall 17 and a protecting roof 18 while the rear side essentially is left free. The driver of the truck will be seated essentially perpendicularly to the longitudinal direction of the truck and consequently the drivers seat 19 is located at one 14 of the lateral walls and turned towards the other 15. Furthermore a steering wheel 20 for the steering of the truck is located at the latter wall while different control means 21 for the controlling of travel direction and lifting means are arranged on the front wall 17 of the cabin. On this there is also an arm support in the shape of a cushion 22.
This invention concerns as mentioned a further development of drivers compartments of the kind that is apparent from fig 1. In fig 2 the same reference numerals are used for corresponding details and the figure thus shows a cabin interior seen towards one lateral wall 15 of the cabin and the front wall 17. Instead of a traditional steering wheel and fixed controls on an instrument panel this truck has a control panel 25 common to these controls that is supported on a movable supporting arm 26. The control panel 25 is an elongate body with an upper and a lower side 27, 28, the steering wheel 20 being mounted on the upper side 27 at one end 29 of the elongate body. The steering wheel is in miniature with a diameter of about one hundred millimeters and the entire length of the control means is about 500 millimeters. The steering wheel is in a known manner arranged for electrical control of the driving and steered wheels 23 of the truck why only small easy movements are required for steering the truck. On the upper side of the panel 27 to the left there is further a plate 30 that is slidable laterally in accordance with the double arrow 29. The movement can be achieved with the palm of the hand and controls the travel direction of the truck forwards or backwards. The control means 21 further includes a number of control sticks 31 - 34 intended for different special functions. With the control stick 31 the lifting device 13 is moved vertically along the lift mast 12 and with the control stick 32 the entire mast 12 can be moved forwards along the chassis away from and back to the front cabin wall 17. The control stick 33 is arranged for an inclining of the forks 13, so called tilting, while the control stick 34 can move the forks 13 laterally, so called side shift. The control sticks 31-34 are preferable controlled with the fingertips of the hand, the palm of which lies against the travel direction switch 30 why many of these functions can be executed simultaneously by a trained driver. common for all control means are that they are arranged for electric control which makes them very easy to move and at the same time the positioning becomes very exact.
The control panel 25 is as mentioned carried on the support arm 26 that in turn is supported on a slide device 35 mounted in the cabin wall 17. The slide device runs along a pair of rails 36 inside the wall and can be displaced according to the arrows 37 in fig 3 from or towards the driver. The support arm is hingedly fastened in slide as well as in control panel and can be pivoted around the pivot axles 38 and 39 as the arrows 40 and 41 also illustrate. The support arm 26 is coupled to a gas spring 42 that in addition to general damping and balancing also is arranged to force the control panel 25 upwards after ended driving and the release by a lock or fixing device. In this way the drivers passing in and out is facilitated. The support arm is preferably further placed close to the truck wall 17 to simplify passing in and out and to reduce the risk of casualties to the drivers legs and knees. To achieve a suitable placing of the steering wheel the control panel 25 protrude from the wall, at least half the panel length. The width of the panel allow a comfortable extending forward of the arms of the driver.
The described control panel 25 can thus by movements in the different free movement directions according to the arrows 37 40 and 41 be adjusted so that the height and the distance to the drivers seat always is adapted to the present driver and his wishes. Since steering wheel and control means will be situated symmetrically on the same distance from the driver, unnecessary oblique positioning of the body is avoided since the two hands of the driver does not have to work on two different distances. In the shown example one hand of the driver may rest on and around the steering wheel 20 while the other can rest on the travel direction plate 30 or on the panel 30 itself. The same arm and hand that is used for the actuation of the control means can preferably also be supported via an elbow support 43 on the wall, the support cushion 44 of which may be pivotable inward towards the drivers seat around an axle 45. Thereby the support cushion 44 may be directed straight towards the control means 21 and provide a longer and more comfortable support for the forearm.
It is also possible to have the control sticks mounted on the laterally slidable direction plate 30.
The direction plate 30 may be substituted for a thumb switch gripping the thumb on both sides for lateral displacement either way.
Instead of having the support arm carrying the control panel slidable from and towards the driver the arm itself may be adjustable to its length, which provides more room for other devices. In order to provide even more possibilities for adjustment the panel can be tiltable sideways or pivotable in a horizontal plane. The latter in case the driver tends to sit slightly turned. Ultimately the arm may in its ends be movable and fixable in ball joints to enable any desired adjustment of the steering and control panel according to the invention.