Motor vehicles – With means for promoting safety of vehicle – its occupant or...
Reexamination Certificate
2001-02-14
2003-03-11
Dickson, Paul N. (Department: 3616)
Motor vehicles
With means for promoting safety of vehicle, its occupant or...
C280S748000, C296S190030
Reexamination Certificate
active
06530448
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a restraint system for drivers of fork lift trucks with a driver's seat located in an open driver's cab.
2. Description of the Prior Art
To prevent serious injuries when a fork lift truck tips over, it is known in the prior art to equip the driver's seat with a lap belt. When used correctly, the lap belt prevents the driver from falling between the fork lift truck and the floor or road if the fork lift truck tips over. As a rule, however, this restraint system is frequently not used because drivers find it tedious to have to fasten and unfasten the belt every time they enter and exit the fork lift truck. When attached, moreover, the belt restricts the driver's freedom of movement on the driver's seat, e.g. when the truck is being operated in reverse and the driver turns around backward so that he can see where he is going. Moreover, one problem frequently encountered when retrofitting older fork lift trucks with lap belts is that the driver's seat is not designed for such retrofitting.
An object of the present invention is to make available an improved restraint system that can also be retrofitted on older fork lift trucks.
SUMMARY OF THE INVENTION
The present invention relates to a fork lift truck having, at least on one side of the driver's seat, a protective grate that is fastened to the protective roof of the driver's cab. The grate can be pivoted around an axis of rotation located in the vicinity of the rear end of the driver's seat out of a closed position in which it is approximately parallel to the driver's seat, outward into an open position. The protective grate can be fixed in the closed position. A protective grate of this type can be easily attached to an existing fork lift truck regardless of the configuration of the driver's seat, and is very easy to operate. Because the distance between the driver's seat and the protective roof of the driver's cab is largely the same on most common fork lift truck models, one standard model of the protective grate can be used for most different models of fork lift trucks.
For example, on a driver's seat that is to the left of center (i.e., standard location) generally all that is necessary is to equip only the left side of the fork lift truck with the restraint system of the present invention.
It is also possible, however, in particular when the driver's seat is located in the middle, to locate a protective grate on each side of the driver's seat.
In one advantageous refinement of the present invention, means are provided for the automatic closing of the protective grate.
The protective grate can be closed easily and automatically if there is at least one spring that pushes it toward the closed position.
The same effect is achieved if the axis of rotation is inclined slightly forward. The protective grate thereby moves toward the closed position under the force of gravity.
The protective grate can be locked manually to fix it in the closed position. It is also possible to achieve an automatic locking of the grate in a terminal position at the end of the closing process actuated by the device's own weight and/or under the force of a spring, e.g. by means of an easily operated spring-loaded latch.
It is preferable if the protective grate has a frame with a plurality of transverse struts. A protective grate of this type presents practically no interference with the driver's vision to the side. A grate of this type can also be manufactured easily and thus economically.
For safety reasons, it is advantageous if the frame and/or the transverse struts are located so that when the protective grate is closed, it is impossible for the driver to slide out sideways, and/or for the driver to extend his head out of the driver's cab.
In arrangements in which inside the driver's cab there is a hood on which the driver's seat is located, it is further advantageous if the protective grate has a support element that is effectively connected with the hood whereby when the protective grate is in the closed position, it is impossible to open the hood or the distance the hood can be opened is limited. This arrangement makes it impossible for the hood and any traction battery that may be located underneath it from moving an unacceptable distance toward the driver.
For an easy adaptation to different hood geometries, the support element is advantageously provided so that it can be adjusted and/or is spring-mounted.
In one advantageous embodiment of the invention, the protective grate can be locked in the closed position depending on whether the driver's position is occupied and whether a key switch is activated. To fix it in the closed position, the protective grate is not mechanically locked by hand, as described above, and by spring force, for example, but the protective grate is fixed in the closed position by an automatic locking device that is appropriately or operatively connected with a seat occupation switch and the (ignition) key switch.
To unlock the protective grate, it is not necessary to first extract the ignition key if the automatically locked protective grate can be unlocked by an additional switch element such as a push button.
To reduce the danger of injury in the event the fork lift truck tips over, the protective grate has damping means in the vicinity of the driver's shoulders, which damping means reduce the impact of the driver against the protective grate when the fork lift truck tips over. The damping means can be provided, for example, in the form of flexible or spring-mounted transverse struts or in the form of an upholstered pad.
REFERENCES:
patent: 4065167 (1977-12-01), Wright
patent: 4388980 (1983-06-01), Vig et al.
patent: 4392669 (1983-07-01), Martin, Jr.
patent: 4619479 (1986-10-01), Martin, Jr.
patent: 5135080 (1992-08-01), Haston
patent: 5286081 (1994-02-01), Martin, Jr.
patent: 6065185 (2000-05-01), Breed et al.
patent: 6189954 (2001-02-01), Martin, Jr.
patent: D440373 (2001-04-01), Meinhardt
patent: 6299207 (2001-10-01), Bares
D. Elbracht, U. Weiner and G. Pfeiffer, Rückhaltesysteme Für Gabelstaplerfahrer, Sep. 30, 1998, cover and pp. 100-110.
Abels Theodor
Will Harald
Dickson Paul N.
Dunn David R.
Linde Aktiengesellschaft
Webb Ziesenheim & Logsdon Orkin & Hanson, P.C.
LandOfFree
Restraint system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Restraint system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Restraint system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3013254