FR2526559A1 - Oscillograph for recording graphic art patterns - has two concentrically mounted pendulums whose centres of rotation are almost superimposed - Google Patents

Abstract

A tracing arm acts on a oscillating platform which has a pendulum mounted underneath it. This has a semi spherical shape which locates in one of two concentric cups mounted in a hole on a table. Two sets of ball bearings keep friction to a minimum and allow the pendulum to turn on themselves to increase the range of possible traces. Variation of the relative movement between the two pendulums is controlled by adjustment of the respective counterweight to adjust the respective periodic movement. Appropriate fixing methods allow vertical or horizontal displacement of the table if a ballast fluid is added or removed.

Description

The present invention relates to an oscil recording device
combined lations of two pendulums, the respective centers of rotation of which are
either confused or very close in space.

Known oscillographs of this kind have either a pendulum or
non-rigid fasteners (strings), or pendulums distant from each other
with intermediate parts allowing them to be connected together. These devices do not allow simple, complex, regular, extremely varied, large area and reproducible figures to be produced.

 The device according to the invention makes it possible to considerably increase the graphic possibilities linked to pendulum movements. The fact of associating two pendulums, the centers of rotation of which are either merged or close in space makes it possible to significantly reduce the variations during pendulum oscillations between the support receiving the plot and the tracer instrument.

This small variation in distance allows, in the graphic execution, a remarkable precision and a reduction to the maximum of harmful friction.

 Some embodiments of the invention are described below by way of indication and in no way limitative, with reference to the accompanying drawings.

 Fig. 1 shows an exemplary embodiment intended to be suspended, the oscillating system of which is a double gimbal with knives.

 Fig. 2 is a plan view of the double knife gimbal of the previous figure.

 Fig. 3 shows an exemplary embodiment intended to be fixed on the edge of a table and the oscillating system of which is a gimbal with axes.

 Fig. 4 is a sectional view, the oscillating system of which is a double ball bowl.

 Fig. 5 is one. cross-section of which the oscillating system is a double gimbal with ball bearings and whose plate in portion of convex sphere is in an almost vertical plane.

 L fig. 6 is a plan view of the double gimbal with ball bearings.

 Fig. 7 shows an exemplary embodiment, the oscillating system of which is a double concentric ball joint, with a plate in the form of a concave sphere and an hourglass system as a tracer instrument.

 Fig. 8 shows an example of suspension allowing the tracer instrument to be in the axis of the pendulum which carries it.

 Fig. 9 shows an example of a pendulum tracking system and a remote control for starting and stopping the tracer instrument.

 Figure 1 shows all the elements to understand the principle of the invention. A plate 1 on which will be traced and a tracer pendulum 2 with a suspension instrument holder are both articulated on a support 3 which, in this case, is screwed on the underside of a horizontal surface (ceiling by example). On each of the legs of the support 3 is fixed a knife which will receive the intermediate frames 4 and 5. By means of other knives, these frames are the supports of the tracer pendulum 2 and of the outer frame 6 associated with the plate 1.

 Figure 2 is a plan view of these same knives gimbals formed for one of the tracer arm 2 and the intermediate frame 4, and for the other of the intermediate frame 5 and the outer frame 6 from where the legs now go the tray.

 Figure 3 shows a table model where we find the two concentric gimbals. The plate 1 oscillates directly on the intermediate frame 5 and the tracer pendulum 2 oscillates on a part 7 in "U" shape. It may be that for manufacturing purposes, as indicated in this figure, the two pendulums are not strictly concentric, but this approximation is not sufficient to depart from the present invention.

 Figure 4 shows another application of the invention where these are two concentric cups 8 and 9 which allow the oscillations of the plate 1 and the tracer arm 2. Under the plate 1 is fixed a pendulum 10 which comes sJembofter, thanks to its shape in a semi-sphere, in the bowl 9. Two rows of balls placed on the cups ensure minimum friction during oscillations. The fact of mounting the pendulums on ball bowls allows them to turn on themselves, and thus the diversity of possible layouts is increased. To vary the relative movement between the two pendulums, one can act on their respective periods thanks to the counterweights 11 and 12. By appropriate fixing systems, they can either move vertically or horizontally, or empty and fill if it is a fluid ballast and this both stops and during the tracing.

 The section in Figure 5 shows a plutgt oscillograph intended for graphic work where a horizontal plate would be a ghe (aerography for example).

The plate 1 in the form of a portion of a convex sphere associated with the frame 6 oscillates by ball bearings on the intermediate frame 5, itself oscillating on the support frame 3. On the frame 6 associated with the plate 1 oscillates a buffer frame 13, which prevents the two pendulums from interacting too strongly. The tracer pendulum 2 also oscillates by ball bearings on an intermediate frame 4 which comes to nest in the frame 13. On the tracer arm is fixed a gun 14 supplied with compressed air by the pipe 15 placed so that it not the pendulum in its movement. The plate 1 can be adjustable in inclination, in distance and possibly with a star associated with a mechanism ensuring its rotation during the tracing.

 Figure 6 allows to see more precisely the place of the different frames of the two concentric gimbals of the previous figure.

 FIG. 7 shows an attractive garden mobile intended for children applying the present invention. The plate 1 in the form of a concave sphere portion and the tracer pendulum 2 are suspended from a rigid support 3 by means of a double ball joint i6. A cone attached to pendulum 2 lets sand, possibly colored, flow regularly towards the plate. For the same principle of the hourglass, we can use an oscillograph to deposit the enamel powder on pieces to go in the oven, dyes or paraffin for painting on fabrics, etc.

 Figure 8 shows a suspension of a plotter specially designed to give maximum fidelity to the plots. The tracer pendulum 2 is provided with three fixing lugs 18, on which pivot three arms 19 connecting the counterweight in a crown 20 to the instrument holder mandrel 21. The tracer instrument being substantially in the axis of the pendulum, the friction will be mimes in all directions of oscillation.

 FIG. 9 associates with the plate 1 and the tracer pendulum 2 respectively two reference hands 22 and 24 coming directly from two reading grids 23 and 25 giving the possibility of carrying out systematic research on the pendulum movements, or of reproducing at will the mimes drawn. There is also a system for lifting the tracer instrument, which by means of the rope 26 and the return spring 27 makes it possible to remotely control the start, the stop and possibly the momentary interruptions of the layout. This remote control may as well use an electrical, ultrasonic, optical system or any other suitable means.

 In a different use, it will be possible to associate with the pendulums mirrors, lenses, prisms or any other system to deflect a light beam (laser, possibly) or make it modify its appearance (intensity, spectrum or width for example) .

 It is understood that the present invention is not limited to the embodiments described and shown, which constitute only examples to which numerous modifications can be made without departing from the present invention.

 The device, object of the invention, can be used in all cases where the precise recording of two pendulum movements is desired, notably in the graphic arts, research in applied physics. It can be used as an attractive toy, mobile commute, as an educational object or as a tracing machine (engraving, drawing, enamels, serigraphy ...). A particularly interesting application can be the simultaneous execution of a graphic optical layout and an image by laser beam projected on a screen giving the same figure.

Claims (10)

EVEimDICATlONS  1) System of two oscillating pendulums used for the execution of tracings characterized in that it comprises for each pendulum (1 and 2) a lifting device (3, 4, 5, 6, fig. 1 and 2) (5 , 7 fig. 3) (8,9, fig. 4) (3, 4, 5, 6, 13, fig. 5 and 6) (3, 16, fig. 7) designed so that their center of rotation are exactly or substantially concentric and where one of the pendulums is used for the support receiving the traces (1) and the other for the tracer instrument (2).  2) Device according to claim 1 characterized by a rotating system associated with one of the pendulums (1, fig. 4 and 8), or both to increase the richness of the traces.  3) Device according to claim 1, characterized by a plate, on which the trace is made, placed in a non-horizontal plane (1 fig. 9).  4) Device according to claim 1, characterized by a plate in the form of a portion of a convex sphere (1, fig. 5) or concave (1, fig. 7).  5) Device according to claim 1, characterized by a system modifying the execution of the traces by displacement of one or more masses associated with the pendulums (11, 12, fig. 4 and 5), during execution or at stop.  6) Device according to claim 1, characterized by a single tracer instrument holder (21, fig. 8) whose counterweight (s) (20) are placed in a ring around the instrument, which therefore is in the axis of the pendulum.  7) Device according to claim 1, characterized by a tracer instrument (7, fig. 7) letting flow a fluid material on the support of the trace, like an hourglass.  8) Device according to claim 1, characterized by a remote control (26, 27, fig. 9) allowing at any time to interrupt or resume the execution of the trace.  9) Device according to claim 1, characterized by a tracking system (23, 25, fig. 9) making it possible to note the mode of execution of the traces and to reproduce them later.  10) Device according to claim 1, characterized by an optical system associated with the pendulums (1 and 2) modifying a light beam during oscillations.