Implements or apparatus for applying pushing or pulling force – Single throw lever – Mechanically actuated
Patent
1984-01-19
1985-10-29
Schmidt, Frederick R.
Implements or apparatus for applying pushing or pulling force
Single throw lever
Mechanically actuated
187 871, 187 18, B66F 300
Patent
active
045497206
DESCRIPTION:
BRIEF SUMMARY
FIELD OF INVENTION AND PRIOR ART
This invention relates to a device of the kind defined in the preamble of appendant claim 1.
Such a device is known by FR-A No. 1 560 817. In this device, the element producing the wedge action is formed by a slide, which is guidedly movable in a horizontal path. The element has the character of a long beam, at the outer end of which the wedge portion is arranged. When the wedge portion, which apart from the contact with the support arm is freely located, urges the support arm to pivot upwardly, the element is exposed to a downwardly directed force giving rise to a torque, which may cause jamming with regard to the guiding of the element relative to the stand since this guide has to maintain the element in the horizontal path of movement and prevent pivoting downwardly of the wedge portion. Furthermore, a hinge between the wedge element and the power mechanism is, in the device according to the patent, located above the area of contact between the dog and the support arm or the part connected thereto, which on displacement of the element in order to pivot the support arm upwardly, gives rise to a torque on the element tending to pivot its wedge portion downwardly, which causes additional risk of jamming and loss of energy.
BRIEF DISCLOSURE OF THE INVENTION
The object of the invention is to devise a way for reducing the deficiencies discussed hereinabove.
This object is primarily obtained by that defined in the characteristic of claim 1. In this way, an embodiment is obtained, in which the forces acting on the wedge portion of the element in a direction downwardly during lifting of the support arm are balanced by means of the portion of the stand located therebelow so that the guide problems occurring in the French patent discussed previously are eliminated. This is in particular due to the fact that the mobility of the wedge portion in a vertical sense eliminates such breaking stresses which may occur in the device according to the patent by those guides which serve to maintain the element in its horizontal path of movement. Moreover, the design according to the invention makes it possible to obtain, by location of the hinge between the wedge element and the power mechanism below the area of contact of the dog, such actuation of the wedge portion that it will move upwardly during pivoting upwardly of the arm. Thus, the wedge element will urge the arm upwardly also when the proper wedge action has been terminated, i.e. when the wedge portion has entered out of contact with the stand.
SHORT DESCRIPTION OF THE DRAWINGS
With reference to the appended drawings, a more specific description of an embodiment example of the invention will follow hereinafter.
In the drawings:
FIG. 1 is a view from the side of the device according to the invention with the support arm lowered;
FIG. 2 is a plan view of FIG. 1;
FIG. 3 is a view illustrating the support arm somewhat pivoted upwardly; and
FIG. 4 is a view illustrating the support art fully pivoted upwardly.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
The device illustrated in the drawings for raising and lowering objects comprises a stand 1 having two longitudinal beams 2 and cross beams 3 arranged at the ends of beams 2. Legs 4 are provided at the outer ends of the cross beams. A support arm 5 is pivotably journalled to the stand about a generally horizontal axis 6. The object to be handled, such as a bed frame, a work table or the like, may be attached in a manner known per se at the upper end of support arm 5 and the cross piece 7 provided thereon. A power mechanism 8 is adapted to pivot arm 5. The mechanism is constituted by a piston cylinder mechanism.
The mechanism 8 is connected to an element 11 which is introducable between portions 9 and 10 of the stand 1 and support arm 5 respectively, said element producing, in cooperation with said portions 9, 10, a wedge action tending to pivot the arm upwardly from the stand.
The element 11 is displaceable generally perpendicularly to the pivot axis 6 of arm 5 and has a wedge sh
REFERENCES:
patent: 2706102 (1955-04-01), Cresci
patent: 3032319 (1962-05-01), Dale
patent: 3901356 (1975-08-01), Butler
patent: 4114854 (1978-09-01), Clark
Hartman Judy J.
Schmidt Frederick R.
LandOfFree
Device for raising and lowering objects does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for raising and lowering objects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for raising and lowering objects will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-725676