US1915890A - Mechanical time fuse for artillery projectiles - Google Patents

Description

June 27, 1933. JUNGHANS 1,915,890

MECHANICAL TIME FUSE FOR ARTILLERY PROJECTILES Filed July 30, 1931 2 Sheets-Sheet 1 flffarwey June 27, 1933. 4 H. JUNGHANS 1,915,390

MECHANICAL TIME FUSE FOR ARIILLERY PROJECTILES Filed July so, 1931 2 Sheets-Sheet 2 .1 2 4 H [five-77:01"; eZmuZ tfung'zzaws M W ALZoz-ney Patented June 27, 1933 UNITED STATES PATENT OFFICE HELMUT JUNGHANS, 0F SCHRAMBERG, GERMANY, ASSIGNOR TO SOCIETA ANONIMA. ARTURO J UNGHAN S FABRICA DOROLOGERIA, OF VENICE, ITALY MECHANICAL THEE FUSE FOR ARTILLERY PROJECTTLES Application filed July 30, 1931, Serial No. 554,101, and in Germany August 15, 1930.

The present invention relates to mechanical time fuses for artillery projectiles and more particularly to a time fuse of the stated kind wherein the necessary moments of force are obtained exclusively by means of centrifugal weights.

In fuses of this type as hitherto constructed the driving toothed segments or racks are adapted to mesh directly with a pinion keyed to or integral with the central shaft of the fuse,said shaft carrying the usual'setting disk and being arranged to perform a single revolution only during the most prolonged trajectory or flight of the projectile, whereas according to the present invention, a means for transmission from a lower to a higher speed is interposed between the said segments and the central shaft, said means comprising a system or set of toothed wheels.

The provision of such a transmission means between the driving segments loaded with centrifugal weights,and the central shaft of the fuse entails a marked advantage over the time fuses of this type as hitherto constructed or suggested, inasmuch as the said'centrifugal weights will have to travel a path of minimal length only in order to cause the central shaft to move and perform a full revolution. In

this way the difference in the positions of thetance between the centrifugal weights and the rotation axis.

Thus the reduction of the path or travel of the segments will act to obviate and decrease the unevenness or disproportionof the drivconnection with the accompanying drawings, forming a part of this specification and showing somewhat diagrammatically for purposes of exemplification, a preferred form and manner in which the invention may be embodied and practised, but without limiting the claimed invention to such illustrative instance:

Figure 1 is a rear view partly in section of the fuse, and

Figs. 2 to 5 are graphic representations indicating the calculations of the centrifugal forces.

The two centrifugal weights a are firmly attached to toothed segments a pivotally mounted on supporting studs 6 so as to be adapted to turn thereabout. The two segments a engage in pinions c firmly connected or integrally formed with toothed wheels d constituting the means for transmission from a lower to a higher speed, between the segments a and the central shaft e, the arrangement being such that both wheels el engage at diametrical points in a pinion keyed to or integral with the shaft e and adapted to actuate in a known manner both the setting disk and regulating means of the fuse;

Figures 2 to 5 of the drawings illustrate graphically two calculations of the driving centrifugal forces, Figure 2 showing the calculation of the driving centrifugal forces of: the prior construction, wherein the segment immediately engages in the pinion of the central shaft. In this case the weight ap-- pended to the segment will travel a path of 10 mm length at or for a full revolution ofthe central shaft. V Apart from the centrifugal forces acting upon the weight of the segment, the tangential forces are plotted and converted to the pitch circle of the pinion of the central shaft Figure 4 is a diagram showing the said tangential forces in the form of a curve. It will be seen therefrom, that the force at the beginning of the movement bears a proportion of 1 to 3, 4 to the force exerted at the end of the movement.

Figure 3 illustrates the same graphical calculation or lotting respecting the construction of the filse according to the present injectile decreases durin vention, wherein the segments do not immediatel mesh with the pinion of the central shaft ut rather engage in a separate pinion formed integral with a toothed wheel meshing with the pinion of the shaft. In this way, that is due to the transmission. means provided in my fuse, the movement or travel of the weights will amount to 3, 5 min. only, while the movement of the central shaft, that is one revolution in case of a most prolonged flight or trajectory, will be the same. In Figure 3 the tangential forces at the center of gravity of the segment like'wise are plotted from the centrifugal forces by division and the said forces are correlated to the pitch circle of the pinion of the central shaft with consideration of the transmission efiected in this case. L

The tangential forces are similarly shown in Figure 5 in the form of a diagram from which will be seen that the force at the commencement of the movement bears a relation of 3 to 4 to the force prevailin at the end' of the movement. Smce, as ereinbefore mentioned, the rotating speed of the prothe flight approximately in the same ratio, an approximately uniform driving force is likely to prevail at such a. proportion or condition of the forces during the entire flight or trajectory.

From the foregoing it is believed, that the advanta es and novel features of my invention wil be readily understood, and, therefore, further detail description is deemed unnecessary. I desire, however, to emphasize the fact that various minor. changes in I the details of construction and in the proportion of parts may be resorted to when required, without sacrificing any of the advantages of my invention as defined in thehaving a setting disk, comprising two pivotally mounted toothed segments, centrifugal weights associated with the said segments, a central shaft, a pinion keyed to the shaft, 21

pair of spur gears meshing with the said pinion, and a pair of pinions associated with the said two spur gears, respectively, and engaging in the said two segments, respectively.

In testimony whereof'I aflix my signature.

HELMUT JUNGHANS.

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