A WINDING MACHINE COMPRISING A WIRE CATCHING MEMBER FOR THE PROVISION OF TAPPINGS

Abstract: For the automatic provision of tappings by winding annular cores, a winding machine comprising an annular wire guide member (1) rotatable about its own axis, the path of movement of which encircles the cross-section of the core, is provided with a hook-shaped wire catching member (10) which by pivotal movement about an axis (11) parallel to the winding plane (8) against a first bias force may be carried from a rest position (10a) outside the winding plane (8) to a catching position (10b) engaging the winding plane (8) to receive a loop of the winding wire (9). The wire catching member (10) is influenced by a second, oppositely directed bias force (37) against which, after having caught a wire loop in the catching position (10b) it is carried to a retaining position (10c) between the rest and catching positions (10a, 10b) and outside the winding plane (8) due to the tightening of the wire (9). The activation force for the movement of the wire catching member (10) is maintained in a prescribed ligation period after occupation of the retaining position (10c).

Description: A Winding Machine Comprising a Wire Catching Member for the Provision of Tappings. The present invention relates to a winding machine for the winding of closed, substantially annular cores comprising guide and driving means for rotatable support and advance of a ' core to be wound about its own axis in a first plane and a substantially annular wire guide means and control and driving means for rotating movement of the wire guide means in a winding plane perpendicular to said first plane so that the path of movement of the wire guide means encircles the cross- section of the core. In the winding of annular cores to be used for instance in transformers, one or more tappings must usually be provided from one or more partial windings to be wound on the core. Such tappings must frequently be provided not only at the ends of a continuous winding but also at one or more points centrally of the winding, for instance when producing windings with a centre tap¬ ping. In the use of conventional winding machines of the type concerned it has been necessary for the provi¬ sion of tappings to stop the winding- operation and manually draw out a loop of the wound wire and fix it when winding a number of successive windings. Besides inherently prolonging the duration of the winding oper- ation the necessity of such manual operations consti¬ tutes a considerable obstacle to the automation of winding operations of the kind concerned. ■ It is an object of the invention to eliminate this obstacle so that tappings may be provided arbitra- rily on a winding by selective operation or by automat¬ ic, programmed activation without stopping the winding operation. O. PI This is obtained according to the invention by a design of a winding machine of the kind concerned which is characterized in that a hook-shaped wire catch¬ ing member is disposed to be pivotable about an axis parallel to the winding plane in order to perform a pivotal movement when exposed to an activating force against a first bias force from a rest position outside the winding plane to a catching position in which it grips into the winding plane to catch a wire loop, by the tightening of which the wire catching member is caused to move backwards against a second bias force acting in the opposite direction of and being smaller than the first bias force to a retaining position between the rest position and the catching position, but outside the winding plane, a member for generating the activa¬ tion force being controlled to maintain said force during a prescribed ligation period after the wire catching member has occupied the retaining position. The invention may be used in connection with any * form of winding machines of the kind mentioned here¬ inbefore irrespective of whether use is made of a wire guide means of the type to be loaded with winding wire prior to the winding operation or of a wire magazine with simultaneous removal of winding wire through a bot- torn outlet slit and supply of winding wire through an inlet slit during • rotation of the magazine in one and the same direction. The invention is applicable to so-called single-ring machines in which the wire guide means is constituted solely by a wire magazine as well as to the so-called double-ring machines in which the wire guide means comprises a separately driven wire advancing ring and a wire magazine co-axial therewith and rotating in the same direction as the wire advancing ring, but independently of its rotation- However, the advantages of the invention with respect to a higher automation level-becomes- particular- ly manifest with winding machines which perform also other phases of a winding operation with a high level automation without the need for manual efforts, for instance a winding machine of the type described in international patent application No. PCT/DK80/00058, international publication No. W081/00841. In the following, the invention will be explained in further detail with reference to the schematical drawings, in which Fig. 1 as an embodiment of a winding machine according to the invention illustrates a side elevation of a winding unit for a single-ring machine. Fig. 2 is a cross-sectional view along the lines II-II in Fig. 1 , Fig. 3 is an exial sectional view of an embodiment of a wire catching member with associated activation means, and Figs. 4 to 6 show details of the embodiment illustrated in Fig. 3. The embodiment shown in Figs. 1 and 2 illustrates the invention in connection with a single- ring winding machine adapted for a high level of auto¬ mation and being of the kind described in the above mentioned international patent application. Figs. 1 and 2 only illustrate the parts of such a winding machine necessary to understand the invention. The wire guide member is constituted by an annular wire magazine 1 journalled in a cassette unit 2 and rotating about its own axis in the direction indicated by an arrow 3. The cassette unit 2 is con¬ nected with a winding machine not shown and containing driving means to rotate the wire magazine and further control and operating means as explained in the above mentioned international patent application. The wire magazine 1 is of the kind in which the supply of winding wire takes place through a fill¬ ing sli * t_, not shown, in the side of the wire magazine facing away from the axis of rotation in the same cycle of operation as removal of wire for winding a core through the bottom slit 4 shown in Fig. 2. The wire magazine 1 may for instance be of the type described in international patent application No. PCT/DK80/00057., international publication No. WO81/00840. As shown, the object to be wound may be constituted, for instance, by an annular iron core 5 disposed in a support arrangement 6, only schematically shown, in such a manner that during the winding operation it is capable of effecting a rotational movement in a plane 7 perpendicular to the winding plane determined by the rotational plane 8 of the magazine 1. The cassette 2 as well as the wire magazine 1 are openable to position the core 5 so that its cross-section is encircled by the path of movement of the magazine 1 in the winding- plane 8 During one revolution of the wire magazine 1 the winding wire 9 drawn out from the bottom slit 4 is guided around in the winding plane 8. In Fig. 1, 9a, 9b and 9c show three different positions of the winding wire 9 during one revolution. For the provision of a winding with a pre¬ scribed number of turns, a corresponding number of revo¬ lutions shall be performed by the wire magazine 1 , each revolution effecting one turn to be wound on the core * 5. At the same time, the wire magazine receives a length of the wire 9 corresponding to the circumferential length of the magazine. Thus, for each rotation a wire surplus is supplied -to the magazine 1 corresponding substantial¬ ly to the difference between the circumferential length of the magazine and the circumference of the cross-sec¬ tion of the core. When a length of wire sufficient for the desired winding has been supplied to the magazine 1 in this way, the wire 9 is cut without stopping the rotation of the magazine 1 which continues until the wire supply in the magazine has been consumed so as to E prevent waste of winding wire. For the purpose of providing tappings at one or more arbitrary points along a winding, a hook-shaped wire catching member 10 is journalled to be pivotable about an axis 11 parallel to the winding plane 8. When exposed to an activation force which may be gener¬ ated by a selective operation or by programmed control the wire catching member 1D is caused to perform a pi¬ votal movement against a first bias force from the rest position 10a ' located outside the winding plane 8 as shown in Fig. 2 on to a catching position 10b as shown in Fig. 6, in which it grips into the winding plane 8 to catch a loop of the wire 9, as shown in Fig. 1. By the tightening of the wire 9 caused by the continuous rotation of the wire magazine 1 the wire catching mem¬ ber 10 will be moved against a second bias force acting in the opposite direction of the first bias -force and being smaller than that force to a retaining position 10c located between the rest position 10a and the catching position 10b as shown in Fig. 6. After occu¬ pation of the retaining position 10c the wire catching member is retained by maintaining the activation force during a ligation period of a duration of a few further revolutions of the wire magazine 1. The wire catching member 10 is mounted on a stationary plate-shaped bracket 12 which in a manner not shown in detail is connected with a stationary part of the winding machine. Fig. 3 shows * an enlarged axial sectional view of the wire catching member 10 with associated activa¬ ting means. In the illustrated embodiment the wire catching member 10 ' is pneumatically activated in that the bracket 12 comprises two hermetically clamped plates 12a and 12b between which a pressure chamber 13 is pro- vided which communicates through a channel 12 with a supply nipple 15 which is connected through a hose, for instance with a source of compressed air positioned When supplying compressir air to the pressure chamber 13 the .membrane 32 is deflected and the main piston 30 is activated so that the membrane together with the connecting rod link 29 are moved from the rest position illustrated in solid line in Fig. 5, in which the axial symmetrical plane of the shaft 16, i.e. the plane through the axes of the end portions 16 and 17 and the eccentrical centre portion 23 is substantially parallel to the plate bracket 12, on to the position shown in dotted lines in which the said symmetrical plane is substantially perpendicular to the plate bracket 12. By this movement, the shaft 16 is turned about 90 against the first bias force illu¬ strated by the arrow 35. In order to generate a second bias force a spiral spring 36 is fixed at one end in the carrier member 25 and at the other end it is in engagement with the driving pin 27 secured in the wire catching member 10. As shown by an arrow 37 the second bias force oper- ates in the opposite direction of the first one illu¬ strated by the arrow 35, i.e. in the same direction as the angular movement of the shaf 16 from the rest position to the activated position. Moreover, the second bias force is smaller than the first bias force which acts on the shaft 16 and thus also on the carrier member 25. Therefore, due to the second bias force shown by the arrow 37 in the rest position 10a and in the catching position 10b the carrier pin 27 will be in abutment against the leading edge 26a of the depression 26 of the carrier member 25 with respect to the rotational direc¬ tion of the shaf 16. When the wire catching means 10 has reached the catching position 10b gripping into the winding plane 8 and has thus caught a loop of the wire- 9, the tighten¬ ing of the wire 9 caused by the continued rotation of the wire magazine 1 will overwin ■ he ' second bias force, thereby carrying the wire catching means 10 to the retaining position 10c outside the winding plane 8 in which the carrier pin 27 abuts against the opposite edge 26b of the depression 26 of the carrier member 25. As a consequence it is prevented that the caught loop of the wire 9 is ligated by the subsequent windings. The force of activation may be generated select- ively by manual operation when a certain number jof wind¬ ings have been wound on the core 5, whereby a timer may be connected with the operating member in order to maintain the force of activation during the prescribed ligation period. In case of automatic working it is preferred, however, to generate the force of activation by programmed control through adjustment of a counter for the number of supplied windings to supply an acti¬ vation signal in one or more desired counting posi¬ tions. In the described embodiment with pneumatical activation the activation signal may influence a sole¬ noid valve in the connection between the above men¬ tioned source of compressed air in the winding machine and the pressure chamber 13. However, instead of the prescribed pneumatical activation other forms of activation are applicable, such as hydraulic or electromagnetic activation.

Claims: PATENT CLAIMS 1. A winding machine for the winding of closed, substantially annular cores, comprising guide and drive means (6) for rotatable support and advance of a core (5) to be wound about its own axis in a first plane (7) and a substantially annular wire guide means (1) and control and driving 'means for rotating movement of the wire guide means (1) in a winding plane (8) perpendicular to said first plane (7) so that the path of movement of the wire guide means (1) encircles the cross-ection of the core (5)-, c h a r a c t e r i z e d in that a hook-shaped wire catching member (10) is dis¬ posed to be pivotable about an exis (11) parallel to the winding plane (8) in order to perform a pivotal movement when exposed to an activating force against a first bias force (35) from a rest position (10a) out¬ side the winding plane (8) to a catching position (10b) in which is grips into the winding plane (8) to catch a wire loop, by the tightening of which the wire catch¬ ing member (10) is caused to move backwards against a second bias force (37) acting in the opposite direction of and being smaller than the first bias force (35) to a retaining position (10c) between the rest position (10a) and the catching position (10b) , but outside the winding plane (8) , a member for generating the activa- tion force being controlled to maintain said force during a prescribed ligation period after the wire catch¬ ing member (10) has occupied the retaining position (10c) ' . - 2.. A winding machine as claimed in claim 1, c h a r a c t e r i z e d in that the activating force and ' he first bias force (35) act on a substanti¬ ally circular sector-shaped carrier member (25) arranged to be pivotable about the same axis (11) as the wire catching member (10) and having on a part of the arc length of its circular outer edge a depression (26) for engagement with a carrier pin (27) stationarily disposed therein, the ends (26a, 26b) of said depres- • εion forming in the activated conditions abutments for the catching pin (27) in the catching position (10b) and the retaining position (10c), respectively, and the second bias force (37) acting directly on the wire catching member (10). 3. A winding machine as claimed in claim 2, c h a r a c t e r i z e d in that the carrier (25) is secured to an eccentric portion (23) of a pivot shaft (16), the wire catching member (10) being journalled to be freely rotatable on said eccentric portion (23) in connection with the carrier (25) , the eccentric portion (23) of the pivot shaft (16) being connected • with a connecting rod link (29) influenced by said means to generate the activating force. 4. A winding machine as claimed in claim 3, c h a r a c t e r i z e d in that the first bias force (35) is generated by a spiral spring (33) in connection with the pivot shaft (16) and a stationary bearing bracket (21) thereof, while ' the second bias force (37) is provided by a spring element (36) in connection with the carrier (25) and the wire catching member (10). 5. A winding machine as claimed in claim 3 or 4, c h a r a c t e r i z e d in that the connecting rod link (29) is provided with a main piston (30) activated by a pneumatic or hydraulic pressure. O.V.PI

Inventors: PEDERSEN JAN BOIE, PEDERSEN, JAN, BOIE
Applicants: TORTRIX AS, TORTRIX  A/S
Application year: 1983
Main classification: H01F41
IPC codes: H01F41