METHOD FOR IMPLEMENTING A CORRECT WINDING OF A WIRE ON A SPOOL

Abstract

A method for implementing a correct winding of a wire on a spool. The method is characterized in that it comprises a step for calculating the angular speed of a motor displacing a wire dispensing device according to the wire winding pitch and according to the pulling error, detected in relation to a given pre-set set-point and to a tolerance value, in order to determine the presence of a possible “valley error”, or of a possible “peak error”. Furthermore, if during the spool winding a “valley error” or a “peak error” is detected, the control device decides whether to slow down or to increase the speed of the wire dispensing device with the aim of filling the valley or of skipping the peak.

Claims

1. Method for implementing a correct winding of a wire on a spool, the method comprising the following steps: (f1) setting the main geometrical data of the spool on an operation panel of the electronic control unit (by means of dedicated formulas or by means of manually entered data); (f2) loading a spool on the machine; (f3) acquiring the position of the spool flanges by means of said sensor; (f4) calculating the actual spool position and comparing it with the “spool data” set in advance in the electronic control unit in order to check whether the spool loading was successful and whether the spool is consistent with that expected; (f5) continuing with the process if the check is positive; or stopping the process and reporting the problem by means of an alarm signal; (F6) binding the wire to the spool; an operator starts the production by activating a specific command; (f7) reading the starting measure of the wire pulling action according to the shape and construction geometry of the support/load cell assembly; (f8) calculating the servodiameter according to the spool data, the production data and the reading of the pulling measure; and (f9) calculating the speed of the spool motor according to the servodiameter with the aim of maintaining a constant winding pulling action; said method characterized in that it comprises a further step for calculating the angular speed of a motor displacing the wire dispensing device according to the wire winding pitch and according to the pulling error, detected in relation to a given pre-set set-point and to a tolerance value, in order to determine the presence of a possible “valley error”, or of a possible “peak error”; and in that if during the spool winding a “valley error” or a “peak error” is detected, the control device decides whether to slow down or to increase the speed of the wire dispensing device with the aim of filling the valley or skipping the peak.

2. Method, according to claim 1, characterized in that it comprises a further step wherein the reversal position of the wire dispensing device is calculated according to the spool flange position detected by the sensor during the spool loading, and according to an error of a device able to measure the pulling action of the wire; said error being used to determine the presence of a valley or of a peak, and therefore to increase or to reduce the reversal position.

3. Method, according to claim 2, characterized in that said device able to measure the pulling action of the wire comprises at least one load cell.

4. Method, according to claim 1, characterized in that it comprises a further step for calculating the length of the wire wound as a skein on the spool.

5. Method, according to claim 1, characterized in that it comprises at least a step of cable data transmission, or wireless transmission, to remote units for controlling the machine and/or the production line.

6. Machine for winding a wire on a spool, characterized in that it can implement a method for a correct winding of a wire on a spool according to claim 1.

7. Machine, according to claim 6, characterized in that it comprises at least one device able to measure the pulling action of the wire, so as to use the detected values for carrying out the correct winding of the wire on the spool.

8. Machine, according to claim 7, characterized in that said device able to measure the pulling action of the wire comprises at least one load cell.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The present invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting example of an embodiment of a machine for winding a wire on a spool, in which:

[0041] FIG. 1 schematically illustrates a machine for correctly rewinding a wire on a spool; said machine being suitable to implement the method which is the main object of the present invention; and

[0042] FIG. 2 illustrates some details of the machine in FIG. 1 on an enlarged scale.

BEST MODE FOR CARRYING OUT THE INVENTION

[0043] In FIG. 1, number 10 denotes, as a whole, a machine for winding a wire on a spool 100, on which the method according to the invention can be implemented.

[0044] The machine 10 comprises the following devices, placed in-line:

[0045] (a) a feeding device 20 of a wire (not shown) to be wound around the spool 100; said feeding device 20 comprises, in a known manner, a pulling ring 21 made to rotate by a synchronous electric motor 22 (for example, a brushless motor) by means of a pair of pulleys 23, 24, linked together by a belt 25; the synchronous electric motor 22 is connected to a relative encoder 26, and it is controlled by an electronic board 27;

[0046] (b) an assembly comprising a load cell 300 (FIG. 2), to which a spindle is attached, on which a wire transmission pulley 34 is rotatably mounted;

[0047] (c) a wire dispensing device 40 comprising a worm screw 41 to control the translation of a pulley 42 of the wire dispensing device along an axis (X1) and following one of the two directions defined by the arrows (F1), (F2); the worm screw 41 is made to rotate by a synchronous electric motor 43 (for example, a brushless motor) by means of a pair of pulleys 44, 45 linked together by a belt 46; the synchronous electric motor 43 is connected to a relative encoder 47, and it is controlled by an electronic board 48;

[0048] (d) a spool assembly 50, comprising said spool 100, on which the wire (not shown) is wound so as to form a skein of wire (not shown); the spool assembly 50 also includes a respective synchronous electric motor 51, which makes the spool 100 rotate (around an axis (X2)—arrow (R)) by means of a pair of pulleys 52, 53 linked by a belt 54; the synchronous electric motor 51 is connected to a corresponding encoder 55 and is controlled by an electronic board 56; and

[0049] (e) a sensor 60 suitable to read the position of the spool 100 and the configuration of its skein containment flanges; in particular, preferably, but not necessarily, the sensor 60 is not mounted on the wire dispensing device 40.

[0050] Incidentally, it should be said that each electronic board 27, 48, 56, coupled with the respective encoder 26, 47, 55, performs both power control functions (used in the conversion from direct current into alternating current), and functions of mere software control of the data received/sent from/to the respective encoder 26, 47, 55.

[0051] According to a preferred embodiment of the invention, a DC bus architecture is used.

[0052] However, using a more complex construction, the same operation could be obtained with DC motors and AC/DC converters and with AC motors and AC/AC converters.

[0053] The electronic boards, 27 48, 56, a load cell 300 and the sensor 60 controlling the spool are connected electronically to an electronic control unit (CC), which may or may not be built into the machine 10, that manages all functions for controlling and operating the components of the machine 10.

[0054] The method according to the present invention comprises the following steps:

[0055] (f1) setting the main geometrical data of the spool on an operator panel of the electronic control unit (by means of dedicated formulas or by means of manually entered data) ;

[0056] (f2) loading a spool on the machine;

[0057] (f3) acquiring the position of the spool flanges by means of said sensor;

[0058] (f4) calculating the actual spool position and comparing it with the “spool data” set in advance in the electronic control unit in order to check whether the spool loading was successful and whether the spool is consistent with that expected;

[0059] (f5) continuing with the process if the check is positive; or stopping the process and reporting the problem by means of an alarm signal;

[0060] (f6) manually binding the wire to the spool; an operator starts production by activating a specific command;

[0061] (f7) reading the starting measure of the wire pulling action according to the construction and geometrical shape of the support/load cell assembly;

[0062] (f8) calculating the servodiameter according to the spool data, the production data and the reading of the pulling measure; and

[0063] (f9) calculating the speed of the spool motor according to the servodiameter, with the aim of maintaining a constant winding pulling action.

[0064] The present method is characterized in that it comprises a further step for calculating the angular speed of a motor displacing the wire dispensing device according to the wire winding pitch and according to the pulling error, detected in relation to a given pre-set set-point and to a tolerance value, in order to determine the presence of a possible “valley error”, or of a possible “peak error”. The method is also characterized in that, if a “valley error” or a “peak error” is detected during the spool winding, the control device decides whether to slow down or to increase the speed of the wire dispensing device with the aim of filling the valley or of skipping the peak.

[0065] The main advantage of the method according to the present invention lies in its reliability. Moreover, to implement the present method, all that is required is a winding machine that envisages the use of a small number of sensors. Furthermore, with the present solution the winding machine operator does not have to continuously/frequently correct the reverse position of the wire dispenser device, thereby reducing the amount of time the operator has to spend on a single machine. In this way, each individual operator can manage a larger number of winding machines.