Machine for working ribbon-shaped elements

Abstract

A machine (1) for working a ribbon-shaped element (T1, T2, T2) is described, comprising at least one cutting station (2) crossed by the ribbon-shaped element (T1, T2, T2), guiding means (3, 4) adapted to position and drag the ribbon-shaped element (T1, T2, T2) onto at least one fixed plane (PI) of the cutting station (2) keeping an edge of the ribbon-shaped element (T1, T2, T2) tangent to a fixed point (A1) of the fixed plane (Pi); at least one of the guiding means (3, 4) rests onto an arm (31) free of rotating with respect to a fixed axis (33); the fixed axis (33) is at the same distance with respect to the cutting station (2) and the at least one of the guiding means (3, 4).

Claims

1. A machine for working a ribbon-shaped element, comprising: an arm free to rotate with respect to a fixed axis of the machine; a cutting station fixed on the machine a distance from the fixed axis, the cutting station defining a fixed plane with a fixed point; and a guiding means fixed on the arm at the distance from the fixed axis, the guiding means adapted to position the ribbon-shaped element onto the fixed plane of the cutting station such that an edge of the ribbon-shaped element is tangent to the fixed point of the fixed plane.

2. The machine of claim 1, wherein the cutting station further comprises a pair of side guides on opposite sides of the fixed plane of the cutting station and configured to guide the ribbon-shaped element over the fixed plane, the side guides fixed on the machine such that a line between the side guides is perpendicular to a line between the fixed point and fixed axis.

3. The machine of claim 2, wherein the guiding means comprises contact elements on opposite sides of the guiding means adapted to drag the ribbon-shaped element therethrough to position the ribbon-shaped element onto the fixed plane.

4. The machine of claim 3, wherein the fixed axis is substantially perpendicular to the fixed plane and a distance between the fixed axis and a line between the side guides coincides with a distance between said fixed axis and a line between the contact elements.

5. The machine of claim 4, further comprising: a second arm free to rotate about a second fixed axis of the machine, the second fixed axis at a second distance from the cutting station, the second arm on an opposite side of the the cutting station with respect to the fixed axis; an operating station fixed on the second arm at the second distance from the second fixed axis.

6. The machine of claim 1, further compromising: an indicating quadrant positioned under a rotational plane of the arm and adapted to check an angular rotation value of the arm with respect to the fixed axis; and a blocking device fixed to the machine adjacent to the fixed axis and adapted to stop the arm, preventing further rotation.

7. The machine of claim 1, further comprising an actuator connected to the arm composed of a motored assembly, of a type coupled with a screw-scroll system, the actuator adapted to rotate the arm with respect to the fixed axis.

8. The machine of claim 5, wherein the operating station is a folding station.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be better described by some preferred embodiments thereof, provided as a non-limiting example, with reference to the enclosed drawings, in which:

(2) FIG. 1 shows an axonometric view of a cylinder of a rotary dinking die in which sections of rectilinear and curvilinear ribbon must be inserted, which can be obtained with an embodiment of the machine for working ribbon-shaped elements according to the present invention;

(3) FIG. 2 shows an axonometric view of a spirally wound rectilinear ribbon, from which the sections of rectilinear ribbon are obtained;

(4) FIG. 3 shows an axonometric view of a helically wound curvilinear ribbon from which the sections of curvilinear ribbon are obtained;

(5) FIGS. 4 and 5 show geometric constructions which are the theoretical foundation for an embodiment of the machine for working ribbon-shaped elements according to the present invention;

(6) FIGS. 6 and 7 shows an axonometric view and a plan view of different configurations of an embodiment of the machine for working ribbon-shaped elements according to the present invention;

(7) FIG. 8 shows an axonometric view of a first preferred embodiment as an example of the machine for working ribbon-shaped elements according to the present invention;

(8) FIGS. 9 and 10 shows an axonometric view and a plan view of a second embodiment as an example of the machine for working ribbon-shaped elements according to the present invention;

(9) FIGS. 11a, 11b, 11c show orthogonally projected views of a slanted joint in a configuration for rectilinear ribbon of an embodiment of the machine for working ribbon-shaped elements according to the present invention;

(10) FIGS. 12a and 12b show orthogonally projected views of the slanted joint, in a first curvilinear configuration; and

(11) FIGS. 13a and 13b show orthogonally projected views of the slanted joint in a second curvilinear configuration.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(12) With reference to FIGS. 1, 2, 3, a piece of rectilinear ribbon DI inserted into a slit GI parallel to the main axis of a cylinder C is obtained by working a spirally wound ribbon-shaped element TI.

(13) A piece of curvilinear ribbon D2 inserted into a slit G2, slanted by a certain angle on the side surface of the cylinder C, is obtained by working a helically wound ribbon-shaped element T2, T2.

(14) With reference to FIGS. 4 to 7, a machine 1 for working a ribbon-shaped element T1, T2, T2 comprises at least one cutting station 2 crossed by the ribbon-shaped element T1, T2, T2, guiding means 3, 4 adapted to position and drag the ribbon-shaped element T1, T2, T2 onto at least one fixed plane P1 of the cutting station 2, keeping an edge of the ribbon-shaped element T1, T2, T2 tangent to a fixed point A1 of the fixed plane P1.

(15) Next to the cutting station 2, the helical trajectory of the ribbon-shaped element T2, T2 can be approximated as purely circular planar figure.

(16) With this approximation, the ribbon-shaped element T1, T2, T2 rests on the fixed plane P1 and the possible edges traced by the ribbon-shaped element T1, T2, T2 remain tangent to the fixed point A1 of the fixed plane P1.

(17) At least one of the guiding means 3, 4 rests on an arm 31 free of rotating with respect to a fixed axis 33.

(18) The fixed axis 33 is at the same distance with respect to the cutting station 2 and at least one of the guiding means 3, 4.

(19) The cutting station 2 comprises a pair of side guides 25, 26 arranged along a line coincident with or parallel with or very near a line 28 resting on the fixed plane P1 passing by the point A1 perpendicularly to the ribbon-shaped element T1, T2, T2.

(20) At least one of the guiding means 3, 4 comprises contact elements 35, 36 adapted to guide and possibly drag the ribbon-shaped element T1, T2, T2. The contact elements 35, 36 are arranged along a line 55 resting on the fixed plane P1 perpendicularly to the ribbon-shaped element T1, T2, T2.

(21) The fixed axis 33 is approximately perpendicular to the plane P1 and the distance between the fixed axis 33 and the line 28 coincides with the distance between the fixed axis 33 and the line 55.

(22) With reference to FIGS. 4, 5, it is possible to clarify the geometric operating principle. A pair of rectilinear segments coming out of a generic point P external to a circumference and tangent thereto in two points A1 and A2 has segments with the same length.

(23) According to the geometric reconstruction, a sheaf of circumferences C1, C2, C3 (this latter one degenerate and coincident with a straight line) tangent to a single point A1 has the property according to which any rectilinear segment coming out of a generic point P whose length is the same as the length between point P and the commonly tangent point A1, is always tangent to any circumference of the sheaf C1, C2, C3 in the respective points A2, A3, A4 coincident with the other end of the rectilinear segment.

(24) With reference to FIGS. 9, 10, at least one operating station 6 rests on an arm 61 free of rotating with respect to a fixed axis 65.

(25) The fixed axis 65 is at the same distance with respect to the cutting station 2 and the operating station 6.

(26) With reference to FIGS. 11 to 13, the ribbon-shaped element T2, T2 follows a helical trajectory with an increasing slant upon increasing the distance from the cutting station 2.

(27) In order to better match the action of the guiding means 3, 4 and that of the operating station 6, a slanted joint allows the arm 31, 61 to change its own attitude depending on the helix radius of the ribbon-shaped element T2, T2, and therefore depending on the higher or smaller curvature with which the section of ribbon must be addressed and positioned on the plane P1.

(28) The slanted joint adapted to connect the arm 31, 61 to an arm 11, 12 integral with the fixed structure of the machine 1 is composed of a pair of slanted surfaces.

(29) With reference to FIG. 8, the machine 1 comprises an indicating quadrant 37 adapted to check the angular rotation value of the arm 31 and a blocking device 38 adapted to stop and block the arm 31.

(30) The indicating quadrant 37 can also be used to check the angular rotation value of the arm 61. The blocking device 38 can also be used to stop and block the arm 61.

(31) With reference to FIGS. 9, 10, the machine 1 can comprise an actuator composed of a motored assembly 39, of the type coupled with a screw-scroll system 54, or directly connected along the fixed axis 33.

(32) According to a preferred configuration of the machine 1, the operating station 6 is a folding station.