Machine element or mechanism – Mechanical movements – Reciprocating to or from oscillating
Patent
1986-01-06
1987-04-28
Scanlan, Jr., Richard J.
Machine element or mechanism
Mechanical movements
Reciprocating to or from oscillating
74106, 74600, 74516, 74522, F16H 2144
Patent
active
046604294
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a device having a pivotable loading lever with a force transmission lever rigidly attached to it, an intermediate piece and a ram which is movable along its central axis for force multiplication according to the lever principle, and relates too to a method of operation of the said device.
Wherever large forces have to be applied over short distances it is useful to employ a force multiplier device. This can for example be in the form of gear transmission, rack and pinion, mechanical force transmission using the well known lever principle (load.times.length of loading arm =force.times.length of force lever), or via compressed air or hydraulic fluid and appropriate ratio of piston area to the area acted upon.
The transmission i.e. multiplication of forces according to the lever principal has for example found wide use in press manufacture, especially in toggle-lever presses. Characteristic of all of these application is the short stroke viz., few millimetres over which the force has to be applied, for example when punching out sheet metal, which calls for very high forces. This task viz., generating a large force via a small lever arm, is readily accomplished using the lever principle by means of a small load and a large loading lever.
The standard way of achieving very short force strokes in known devices is to employ a plurality of force multipliers connected in series. In more highly developed devices the stroke can be changed in a series of steps and can, therefore, be reasonably well adjusted to suit the various requirements of force and stroke.
The object of the present invention is to create a device making use of the lever principle and having a continuously variable transmission ratio by means of which device very short strokes are obtainable using only one force multiplier. A further object of the invention is to develop a method for the operation of the said device which enables compressive and/or tensile forces to be generated with lower applied load.
The object with respect to the device is achieved by way of the invention in that a hollow body with a rigidly attached loading lever features, within a free space a discontinuous axis of rotation for force multiplication, and in the region of discontinuity a U-shaped part with a force transmission axis inserted into the said free space and fixed in place there with the aid of a positioning means, the length of the force transmission lever--in the form of displacement of the axis of rotation with respect to the force transmission axis--being variable on both sides of the axis of rotation by various positioning of the U-shaped piece, and the force transmitted from the loading lever acts on the ram which features alignment means via the force transmission axis and intermediate piece.
A freely variable ratio of applied force to transmitted force leads to solutions which can be accurately suited to the problem in question and, accordingly results in the minimum requirement in energy expenditure. Force multiplication in one single step permits simple mechanical components to be employed. The hollow body and the U-shaped part are connected via an adjustable screw which brings these parts into position with respect to each other such that the desired force transmission lever of length k is formed and--according to preselected direction of rotation--a thrusting or tensile force is produced. The loading lever which is rigidly mounted to the hollow body is--according to the distance of the axis of rotation from the point of load application--of length l.
The magnitude of force multiplication is the ratio of the length of the load lever 1 to that of the force transmission lever k. If the rotation axis and force transmission axis are coincident i.e. on the same axis, then the lever length k=0 and no force can be generated. On the other hand the length of the force transmission lever can be very short e.g. 0.01 cm with the result that a very high transmission ratio is possible. Such high force transmission conditions are advantageous for
REFERENCES:
patent: 1480177 (1924-01-01), Miller
patent: 2106945 (1938-02-01), Francis
patent: 2629327 (1953-02-01), Krause
patent: 2830455 (1958-04-01), Harmon
patent: 3359825 (1967-12-01), Wiig
patent: 3530771 (1970-09-01), Bowman
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