GB1575820A - Coil former for and electrical winding - Google Patents

Description

(54) A COIL FORMER FOR AN ELECTRICAL WINDING (71) We, SIEMENS AKTIENGESELL SCHAFT, a German company of Berlin and Munich, Germany (fed rep), do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a coil former for a winding having a radially inner first end and a radially outer second end and first and a radially outer second end and first and second flexible connecting leads connected to said first and second ends respectively, the former comprising a winding-carrying part; first and second flanges provided one at each end of said part; a third flange spaced axially outwardly of said first flange to define therebetween an annular chamber in which the flexible connecting leads and the first and second ends of the winding may be disposed in use by multiple deflection so as to relieve them of tension.

A coil former of this kind is disclosed in British Specification No. 1,110,192. In order to achieve a predetermined degree of tension-relief, in the case of this known arrangement the flexible connecting leads are inserted into a chamber which is of approximately annular-groove shape and is designed to be substantially rectangular in section, being at the same time deflected twice through 90". The efficacy of such tension relief is, however, not always adequate in practice since the flexible connecting leads are inserted without securing means. During transport of the displaceable coil form they may readily be released and spring back.

German Specification No. 1,804,217 discloses a mode of traction relief which is simple to manufacture and reliable. In the case of the known arrangement, this is achieved in that there are arranged in the annular-groove-form chamber at the inner flange axial projections about which the flexible connecting leads are wrapped with a degree of deflection of approximately 1800 by guiding to and fro in the peripheral direction, whereas the outer flange is formed at the side opposite the axial projections with radial recesses the width of which is larger in the peripheral direction than is the extent of the projections in that direction. It is an important factor in the case of this design that the annular-grooveform chamber has associated wire surrounding pins which take care of positioning the wire and above all provide the necessary traction relief.Since the wire end forms a loop, it is necessary to ensure that entirely satisfactory installation is achieved since slipping-up thereof to the groove edge would result in flash-over (spark-over). Since the wire inserting movements are relatively complicated and furthermore the connecting wires are not reliably retained at the coil form during winding-on and soldering, it would appear that manufacture of such coils cannot be automated.

According to the invention there is provided a coil former for a winding having a radially inner first end and a radially outer second end and first and second flexible connecting leads connected to said first and second ends respectively, the former comprising a winding carrying part; first and second flanges provided one at each end of said part; a third flange spaced axially outwardly of said first flange to define therebetween an annular chamber; two oppositely extending lands provided in said chamber to sub-divide the latter into two subchambers; first and second slots formed in said first flange and disposed one on either side of one of said lands for accommodating said first and second ends respectively; first and second further slots formed in said third flange for leading-out in an axial direction said first and second connecting leads: and paths defined in said sub-chambers for said first and second ends of the winding and for said first and second connecting leads whereby in use each of said winding ends and the respective connecting lead can be laid jointly in a peripheral direction by multiple deflection in the respective subchamber thereby to extend from the respective one of the slots in said first flange on one side of said one land to a position on one side of the other of said lands.

Preferably, a substantial improvement in tension relief may be achieved by providing, in the vicinity of said other land, supplementary deflecting lands such that in use the winding wires and flexible connecting leads jointly directed away from the connecting locations (soldering locations) undergo a degree of deflection which is greater than 90". Furthermore, the coil wire may be guided in an extra groove so dimensioned that the former cannot be crushed by the flexible connecting lead, and thereby torn off.Furthermore, the grooveform sub-chambers or "pockets", which are preferably substantially symmetrical, at their base may be so designed that over a portion of their length they extend parallel to the plane of the first and second lands, and at the same time guide strips which are also arranged parallel retain the flexible connecting leads or the connecting wires in clamp-like manner in the pushed- in position. This is important in particular for automation of coil manufacture. Due to the parallel fixing of coil wire and insulated flexible connecting lead externally of the coil flange, automatic winding-on and cutting-off of the coil wire becomes possible. Since the wound-off ends are arranged vertically, it is also possible to automatically perform moistening with solder. and subsequent immersion soldering involving minimum outlay can also be automatically effected.By bending the soldering locations into the "pocket" the internally located coil wire is relieved of traction stresses. Since the two connecting "pockets" are separated from each other by lands, the bent-in soldering locations are well insulated from each other. Since the flexible connecting leads are led out in the axial direction, not only is adequate tension relief achieved but furthermore the former can, without any kind of interference, be wrapped with a jacket comprising a shrunkon sheath or an adhesive tape. On employing a shrunk-on sheath, the adhesion friction in the connecting "pockets" is still further promoted by axial shrinkage and tensioning of the pocket outer wall. If desired, two "third flanges" may be provided, each associated with a respective one of said first and second flanges.

One embodiment of coil former according to the invention will now be described in more detail, by way of example - only, with reference to the accompanying drawings, in which: Figure 1 is a side view, partly in section, of a coil former according to the invention carrying a finished fine-wire coil winding; Figure 2 is an end view of the coil former with flexible connecting leads for the winding not yet pushed into received subchambers provided therefor; Figure 3 is an end view of one flange of the coil former; Figure 4 is a view, similar to Figure 1, but with the winding omitted; Figure 5 is a sectional view taken on the line A-B in Figure 4; Figure 6 is a sectional view taken on the line C-B in Figure 4; Figure 7 is a sectional view taken on the line E-F in Figure 3; and Figure 8 is a view taken in the direction of the arrow X in Figure 3.

A coil former is designated by reference numeral 1, and has a fine-wire winding 2 provided with flexible connecting leads 3 which are lead-out in the axial direction.

The finally wound coil 2 provided with the connecting wires 3 is, finally, also provided with a shrunk-on sheath 4 (Figure 1).

As will be ascertained in particular from Figures 3 to 8, the coil form has, in per se known manner, first and second flanges 5 and 6 separated from each other by an intermediate part 7 having the shape of a hollow cylinder for carrying the winding 2.

A third flange 8 is so associated with the first flange 6 that there is formed a chamber having the form of an annular groove and which is sub-divided by two webs or lands 9 and 10 into two "pockets" or subchambers 11 and 12.

As may be gathered in particular from Figure 5, at both sides of the land 9, in the inner flange 6, first and second incisions (slots) 13 and 14 of differing depth are provided respectively for the initial portion 15 of the winding wire 2 and for the end portion 16 of the winding wire 2 (Figure 2).

The outer flange 8 has, at both sides of the web 9, first and second incisions (further slots) 17 of equal depth (shown in particular in Figure 6) for the purpose of leading-out the flexible connecting leads 3 (Figures 1 and 2). The base of the pockets 11 and 12 is so designed that the flexible connecting leads 3 connected with the wire ends 15 and 16 undergo, subsequent to insertion thereof into the pockets 11 and 12, a degree of multiple deflection as shown specifically in Figure 2.In order to achieve change in direction to the maximum extent, supplementary deflecting lands 18 are pro vided in the vicinity of the land 10, in such manner that the winding wire ends 15 and 16 and flexible connecting leads 3 jointly guided-away from the connecting locations undergo a degree of deflection of more than 90". In the case of the example of embodiment selected, what takes place is practically a degree of deflection through 1800. In order to facilitate insertion of the winding wire ends 15 and 16 and also of the flexible connecting leads 3, there are provided in the base or bottom of the pockets rectilinear members 19 extending parallel to the slots 13, 14, 17 and the lands 9 and 10.In the members 19 and about the deflecting lands 18 there are formed, for receiving the coil wire ends 15 and 16, thin grooves 20 communicating at the inner coil flange 6 with the incisions 13 or 14. (Figures 5 and 6).

The thin grooves 20 are so dimensioned that the coil wire ends 15, 16 are receivable therein and cannot be crushed by the flexible connecting leads 3 disposed thereabove.

As Figure 2 shows, the two flexible connecting leads 3 are pushed-in laterally and parallel to the lands 9 and 10. To achieve a firm fit of the flexible connecting leads, there are provided on the one hand the rectilinear members 19 and on the other hand also supplementary guiding strips 21 arranged with corresponding spacing relative to the base of the pockets 11 and 12-the spacing corresponds approximately to the diameter of the flexible connecting leads 3.

These guiding strips 21 extend over the rectilinear portion 19 of the pocket base.

In order that, on the one hand, the flexible connecting leads may be readily inserted and on the other hand firm seating thereof guaranteed, these guiding strips 21 have a wedge-form profile.

Manufacture of the coil can now be so effected, in simple manner, that subsequent to application of the winding 2, the winding ends 15 and 16 can be pulled away parallel and downwardly, being thereby pulled into the thin groove 20. Then, the two flexible connecting leads 3 are pushed in laterally into the pockets to such an extent that they are retained by the guiding strips and remain in the Position shown in Figure 2.

Thus, the connecting strips 3 extend parallel with the ends 15 and 16 of the winding wires. Due to this parallel fixing of winding wires 15 and 16 and insulated ends of the flexible connecting leads 3, externally of the coil flange 6 and 8, automatic winding on and severing of the coil wire becomes possible. Since the wound-off ends 22 are arranged vertically, wetting with solder and subsequent soldering involving minimum outlay can also be automatically effected.

However, it would also be conceivable to provide for pivoting movement of the coil into the dipping bath, if the soldered ends 22 are (for reasons connected with saving of space) to be arranged laterally of the flange. Subsequently, the soldered ends 22 are pushed into the pockets in the manner indicated by broken lines in Figure 2. The ends 22 then pass to both sides of the land 10 (Figure 2). Since the two ends 22 are separated by the land 10, they are well insulated. Due to the bending in of the ends 22, the internally disposed coil wire ends 15, 16 are relieved of tensile stressing.

The flexible connecting leads 3 are also pressed into the pockets at the other end and the free ends extend axially out of the slots 17 (Figure 1). Since there are no projecting elements, it becomes possible to sheath the coil without disturbance (as previously discussed).

If the coil according to the invention is employed for example for electric motors then the space which is not required between the two flanges 6 and 8 can be employed for accommodating structural elements of the motor, so as to shorten the structural length of the coil or of the motor.

Figure 3 shows an appropriate recess 23 in the former for receiving a structural portion of the motor.

As will be evident from the foregoing description of the preferred embodiment, there is provided a coil former for an electrical winding in which manufacture thereof can be automated. In the case of conventional manual manufacture of known formers, it is required to perform working steps which involve high wages, for instance to connect the winding ends with connecting wires subsequent to winding, to secure them, to test them for continuity, and subsequently to insulate the entire coil.

WHAT WE CLAIM IS : - 1. A coil former for a winding having a radially inner first end and a radially outer second end and first and second flexible connecting leads connected to said first and second ends respectively, the former comprising a winding carrying part; first and second flanges provided one at each end of said part; a third flange spaced axially outwardly of said first flange to define therebetween an annular chamber; two oppositely extending lands provided in said chamber to sub-divide the latter into two sub-chambers; first and second slots formed in said first flange and disposed one on either side of one of said lands for accommodating said first and second ends respectively; first and second further slots formed in said third flange for leading-out in an axial direction said first and second connecting leads; and paths defined in said sub-chambers for said first and second ends of the winding and for said first and second connecting leads whereby in use each of said

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (12)

**WARNING** start of CLMS field may overlap end of DESC **. vided in the vicinity of the land 10, in such manner that the winding wire ends 15 and 16 and flexible connecting leads 3 jointly guided-away from the connecting locations undergo a degree of deflection of more than 90". In the case of the example of embodiment selected, what takes place is practically a degree of deflection through 1800. In order to facilitate insertion of the winding wire ends 15 and 16 and also of the flexible connecting leads 3, there are provided in the base or bottom of the pockets rectilinear members 19 extending parallel to the slots 13, 14, 17 and the lands 9 and 10.In the members 19 and about the deflecting lands 18 there are formed, for receiving the coil wire ends 15 and 16, thin grooves 20 communicating at the inner coil flange 6 with the incisions 13 or 14. (Figures 5 and 6). The thin grooves 20 are so dimensioned that the coil wire ends 15, 16 are receivable therein and cannot be crushed by the flexible connecting leads 3 disposed thereabove. As Figure 2 shows, the two flexible connecting leads 3 are pushed-in laterally and parallel to the lands 9 and 10. To achieve a firm fit of the flexible connecting leads, there are provided on the one hand the rectilinear members 19 and on the other hand also supplementary guiding strips 21 arranged with corresponding spacing relative to the base of the pockets 11 and 12-the spacing corresponds approximately to the diameter of the flexible connecting leads 3. These guiding strips 21 extend over the rectilinear portion 19 of the pocket base. In order that, on the one hand, the flexible connecting leads may be readily inserted and on the other hand firm seating thereof guaranteed, these guiding strips 21 have a wedge-form profile. Manufacture of the coil can now be so effected, in simple manner, that subsequent to application of the winding 2, the winding ends 15 and 16 can be pulled away parallel and downwardly, being thereby pulled into the thin groove 20. Then, the two flexible connecting leads 3 are pushed in laterally into the pockets to such an extent that they are retained by the guiding strips and remain in the Position shown in Figure 2. Thus, the connecting strips 3 extend parallel with the ends 15 and 16 of the winding wires. Due to this parallel fixing of winding wires 15 and 16 and insulated ends of the flexible connecting leads 3, externally of the coil flange 6 and 8, automatic winding on and severing of the coil wire becomes possible. Since the wound-off ends 22 are arranged vertically, wetting with solder and subsequent soldering involving minimum outlay can also be automatically effected. However, it would also be conceivable to provide for pivoting movement of the coil into the dipping bath, if the soldered ends 22 are (for reasons connected with saving of space) to be arranged laterally of the flange. Subsequently, the soldered ends 22 are pushed into the pockets in the manner indicated by broken lines in Figure 2. The ends 22 then pass to both sides of the land 10 (Figure 2). Since the two ends 22 are separated by the land 10, they are well insulated. Due to the bending in of the ends 22, the internally disposed coil wire ends 15, 16 are relieved of tensile stressing. The flexible connecting leads 3 are also pressed into the pockets at the other end and the free ends extend axially out of the slots 17 (Figure 1). Since there are no projecting elements, it becomes possible to sheath the coil without disturbance (as previously discussed). If the coil according to the invention is employed for example for electric motors then the space which is not required between the two flanges 6 and 8 can be employed for accommodating structural elements of the motor, so as to shorten the structural length of the coil or of the motor. Figure 3 shows an appropriate recess 23 in the former for receiving a structural portion of the motor. As will be evident from the foregoing description of the preferred embodiment, there is provided a coil former for an electrical winding in which manufacture thereof can be automated. In the case of conventional manual manufacture of known formers, it is required to perform working steps which involve high wages, for instance to connect the winding ends with connecting wires subsequent to winding, to secure them, to test them for continuity, and subsequently to insulate the entire coil. WHAT WE CLAIM IS : -

1. A coil former for a winding having a radially inner first end and a radially outer second end and first and second flexible connecting leads connected to said first and second ends respectively, the former comprising a winding carrying part; first and second flanges provided one at each end of said part; a third flange spaced axially outwardly of said first flange to define therebetween an annular chamber; two oppositely extending lands provided in said chamber to sub-divide the latter into two sub-chambers; first and second slots formed in said first flange and disposed one on either side of one of said lands for accommodating said first and second ends respectively; first and second further slots formed in said third flange for leading-out in an axial direction said first and second connecting leads; and paths defined in said sub-chambers for said first and second ends of the winding and for said first and second connecting leads whereby in use each of said

winding ends and the respective connecting lead can be laid jointly in a peripheral direction by multiple deflection in the respective sub-chamber thereby to extend from the respective one of the slots in said first flange on one side of said one land to a position on one side of the other of said lands.

2. A former according to Claim 1, in which the first and second slots extend inwardly from the periphery of the first flange and said first slot is longer than said second slot, and in which said first and second further slots extend inwardly from the periphery of the third flange, are substantially equal in length and lie one on each side of said one of said lands.

3. A former according to claim 1 or 2 wherein said two sub-chambers are substantially symmetrical.

4. A former according to any preceding claim, and having said winding provided thereon.

5. A former according to claim 4, in which supplementary deflecting lands are provided in the vicinity of said other land so that said first and second ends and said first and second flexible connecting leads jointly guided-away from the connecting locations (soldering locations) undergo deflection of more than 90".

6. A former according to any one of the preceding claims, in which there is provided in each sub-chamber a thin groove for accommodating said first and second ends and which is connected with the first and second slots.

7. A former according to any one of the preceding claims, in which the sub-chambers are so formed in their bases that over a portion of their length they extend parallel to the plane of the first and second lands.

8. A former according to claim 7, in which guiding strips are provided for retaining the flexible connecting leads subsequent to insertion with spacing corresponding to the thickness of the flexible connecting leads and parallel to said rectilinear portions of the sub-chambers.

9. A former according to claim 8, in which the guiding strips have wedge-form profiles.

10. A former according to claim 8 or 9, in which the lands, the first and second slots, the first and second further slots, and also the rectilinearly extending portions of the sub-chambers extend parallel to each other.

11. A former according to any one of the preceding claims, and adapted for use with an electric motor in which said chamber is provided with an associated recess for receiving a structural portion of said motor.

12. A former according to claim 1 and substantially as hereinbefore described with reference to, and as shown in the accompanying drawings.