GB1602554A

GB1602554A - Shaded-pole motor

Info

Publication number: GB1602554A
Application number: GB2282378A
Authority: GB
Original assignee: HEIDOLPH ELEKTRO KG
Current assignee: HEIDOLPH ELEKTRO KG
Priority date: 1978-05-25
Filing date: 1978-05-25
Publication date: 1981-11-11

Description

(54) SHADED POLE MOTOR (71) We, HEIDOLPH-ELEKTRO KG., a German Kommanditgesellschaft, of 8420 Kelheim, Federal Republic of Germany, 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:- The invention relates to a shaded-pole motor comprising a yoke and a pole assembly, wherein the pole assembly has arranged thereon coil formers of insulating material which receive the excitation windings in winding spaces which are bounded by means of end flanges provided on the coil formers.

It is an object of the invention to simplify the structure and assembly of shaded-pole motors of this kind.

The present invention provides a shadedpole motor comprising a pole assembly surrounded by a yoke, wherein the pole assembly has arranged thereon at least one pair of coil formers of insulating material which receive the excitation windings, each coil former having a first end flange adjacent the yoke and a second end flange remote from the yoke, and the said first end flanges of the or each pair of coil formers being interconnected by a bendable strip element, the strip element having means for securing a portion of wire connecting the excitation windings received by the respective ones of said pair of coil formers. The coil formers and the strip element are preferably formed in one piece.

The possibility also exists however to produce them separately and to interconnect the coil formers and the strip element firmly, e.g. by rivetting.

A shaded-pole motor in accordance with the invention can conveniently be constructed by a method wherein the coil formers interconnected by the strip element are folded into parallel planes with those flanges connected by the strip element facing one another, the winding wire is arranged within the winding space of one coil former, is secured on the securing means and is then arranged within the winding spaces of the other coil former whilst retaining the same direction of winding rotation, and the coil formers are thereupon folded into a position in which the unconnected flanges are adjacent one another and those flanges connected by the strip element are more remote from one another, and are pushed on to the pole pieces of the pole assembly. The need for joining the conductors interconnecting the excitation windings is thus eliminated, which yields advantages in respect of production technique and economy.

The wire section between the excitau'on windings is held by the securing means, so that it cannot sag when in the operating posi tion. Damage to the wire during the operation of the motor is thereby reliably prevented.

rt has also been discovered to be advantageous that the securing means comprise two tab-like extensions arranged side-by-side on the strip element and bearing resiliently against each other at their extremities. This yields the possibility of an uncomplicated assembling operation, which may also be per formed in wholly automatic manner.

It tis equally possible however to make use of a single peg, around which the wire is wound. Instead of this, provision may be made in accordance with the invention for the fastening means to comprise a strap which is bendable, fixed on the strip element, and which extends over or under the latter. The wire section is inserted and secured between the strip element and this strap. This allows of a flat form of construction.

In one embodiment of the split-pole motor, provision is made for the strap to have its fixed extremity either integrally formed with the strip element or joined to the latter by clamping means, whereas the free extremity of the strap may be folded down over the strip element. Separate straps which have one extremity connected to the strip element e.g. by rivetting, may also be envisaged. For safely and permanently securing the wire section connecting the excitation windings, provision may be made for the free extremity of the strap to apply pressure generated by resilient flexing of the strap and/or to be secured on the strip element by means of at least one press stud or the like. Alternatively, it may be envisaged to establish secure fastening of the wire section in the space between the strap and the strip element by a pressure exerted on the same by the yoke.

According to a preferred embodiment, provision is made moreover for reception means for the winding extremities and connecting conductors to be incorporated on the part of the coil formers adjacent the pole assembly, at the side facing away from the strip clement.

The connection of the coil extremities and connecting conductors by soldering and the protected and stress-free stowage of the same, may be achieved in spaces defined by the said reception means therein. The possibility also exists of interconnecting the winding extremities and the connecting conductors outside the reception spaces, e.g. within the area of the winding spaces, and of causing the connecting conductors to be relieved of tension by leading these through the reception spaces. The desirable tension-relieving action may moreover be undertaken in the area of recesses in the flanges of the coil former. Provision may also be made to join the winding extremities to plug pins in unit with the coil formers, whereon the connecting conductors may be affixed by means of plug sockets. It was proved to be advantageous to equip those flanges connected by the strip element - at the extremities facing away from the strip element -- with strap-like extensions which may be folded over the winding spaces, or the winding and reception spaces, as closure elements for the latter.

An immobilisation of the free extremities of the extensions on the coil former may also be performed, e.g. by connecting means such as press studs.

The scope of the invention is not limited to motors having a specific number of poles, i.e. it may be applied equally in the case of two-pole or multipole motors. In the case of multipolar motors, that is to say equipped with four poles, the coil formers of two adjacent poles may in each case be joined together by a strip element comprising a securing means.

The invention is illustrated by way of example in the accompanying drawings, in which: Fig. 1 is a side view of the stator of a motor; Fig. 2 is a side view of coil formers unfolded into a common plane; Fig. 3 is a perspective view of coil formers; Fig. 4 is a side view of unfolded coil formers; Fig. 5 is a cross-section along the line V-V of Fig. 2; Fig. 6 is a diagrammatic view of coil formers for a four-pole motor, and Fig. 7 is a cross-section corresponding to Fig. 5 through another securing means.

Referring to the drawings, 1 denotes an annular laminated yoke for a two-pole motor, wherein a pole assembly 2 is inset in known manner. Coil formers 4 which receive the excitation windings 8 in winding spaces 7 bounded by flanges 5 which are more remote from one another and flanges 6 which are more adjacent one another, are installed on the pole webs 3 of the pole assembly. The coil formers 4 are produced from a plastics material or some other insulating material. The flanges 5 of the two coil formers 4 are connected at one side (Fig. 1) by a bendable strip element 9.

The strip element 9 is preferably integrally joined to the coil formers 4. Along a part of its length in particular, the strip element 9 bears a foldable strap 10 which, as shown in Fig. 5 is joined in hinged foldable manner or, if produced separately, is secured by clamping means on the strip element 9. At the opposite side from the strip element 9 the flanges 5 have extensions 11 which extend over the winding spaces 7 and possibly incorporate reception means 12 defining spaces for the connecting conductors (not shown). As shown in Fig. 2, the two coil formers 4 may be produced with a plane strip element 9 and plane extensions 11 and as a result of bending over of the strip element 9 and when installed on the pole webs 3, assume the positions illustrated in Fig. 3. The strip element 9 and the extensions 11 act as insulating elements for the windings with respect to the yoke and pole packages. The coil formers 4 have stack-like openings 4' which are produced with the shape and size of the webs 3. The incorporation of a reception space 12 is omitted in the case of the coil formers 4 of the embodiment of Fig. 2. In this embodiment, the connecting conductors may be secured in tension-relieved manner in apertures 13 of the flanges 6. By the provision of plug pins 14 which are joined to the extremities of the excitation windings, a connection of the connecting conductors is obtainable by plugand-socket action.

For installation of the excitation windings 8 on the coil formers 4, these are folded into parallel planes by bending the strip element 9 until the flanges 5 face one another as shown in Fig. 4. The right-hand side coil former 4 for example may be equipped with an excitation winding 8 first, by rotation of the coil formers 4 held in this manner. The extremity of this excitation winding is inserted between the strip element 9 and the strap 10, and after lateral displacement of the two coil formers 4, the excitation winding 9 of the left-hand side coil former 4 may be produced whilst retaining the same direction of winding rotation.

After the coil formers 4 have been folded back together into the position of Fig. 3, these may simply be pushed over the pole webs 3.

The wire section 15 then remains between the strip element 9 and the strap 10. It may be secured by means of connecting devices 16 of the nature of press studs or, as shown in Fig.

1, may be immobilised on the strip element 9 by contact pressure of the yoke 1.

Coil formers 4 for a four-pole motor are shown in Fig. 6. Two coil formers 4 are connected by a strip element 9 in each case, and the connecting wire sections for the excitation windings are immobilisable by means of straps 10.

In Fig. 7, the securing means comprises two adjacent tab-like extensions 17 which bear resiliently against each other at their extremities and between them hold fast the wire section 15.

WHAT WE CLAIM IS: 1. A shaded-pole motor comprising a pole assembly surrounded by a yoke, wherein the pole assembly has arranged thereon at least one pair of coil formers of insulating material which receive the excitation windings, each coil former having a first end flange adjacent the yoke and a second end flange remote from the yoke, and the said first end flanges of the or each pair of coil formers being interconnected by a bendable strip element, the strip element having means for securing a portion of wire connecting the excitation windings received by the respective ones of said pair of coil formers.

2. A shaded-pole motor according to Claim 1, in which the securing means comprises two adjacently arranged tab-like extensions situated on the strip element and bearing resiliently against each other at their extremities.

3. A shaded-pole motor according to Claim 1, in which the securing means comprises a strap fixedly arranged in bendable manner on the strip element and arranged to extend above or below the latter.

4. A shaded-pole motor according to any one of Claims 1 to 3, in which the coil formers and the strip element are formed in one piece.

5. A shaded-pole motor according to Claim 3, in which the strap has its fixed extremity formed integrally with the strip element and the free extremity of the same may be folded down over the strip element.

6. A shaded-pole motor according to Claim 1, in which the said securing means comprises a strap formed separately from the strip element and having one extremity firmly connected to the same.

7. A shaded-pole motor according to Claim 3 or 6, in which the said strap is resilient and is flexed so that a free extremity thereof bears under pressure on the strip element, and/or the free extremity thereof is secured on the strip element by means of at least one press stud.

8. A shaded-pole motor according to Claim 3, 5 or 6, in which the strip element and the strap are held in contact with each other under pressure from the yoke.

9. A shaded-pole motor according to any one of the preceding Claims, wherein reception means for the winding extremities and connecting conductors are situated on said second end flanges of the coil formers.

10. A shaded-pole motor according to Claim 9, in which the reception means comprise devices for securing the connecting conductors in tension-relieving manner.

11. A shaded-pole motor according to any one of the preceding Claims, wherein the flanges interconnected by said strip element have, at the extremities remote from the strip element, a strap-like extension which may be folded over the winding spaces or the winding and reception spaces.

12. A shaded-pole motor according to Claim 11, in which the extensions may have the free extremities secured on the coil former by connecting means such as press studs.

13. A shaded-pole motor according to any one of the preceding Claims, in which the flanges have recesses for the tension-relieved securing of the connecting conductors.

14. A shaded-pole motor according to any one of the preceding Claims, in which the connecting conductors and the winding ex tremities are interconnected within the winding spaces and the connecting conductors are led through the reception spaces for tensionrelieving purposes.

15. A shaded-pole motor according to any one of the preceding Claims, in which the winding extremities are firmly joined to plug pins for the connecting conductors, fixed on the coil formers.

16. A shaded-pole motor substantially as described herein with reference to the accompanying drawings.

17. A method for producing a shaded-pole motor according to any one of the preceding Claims, wherein the coil formers interconnected by the strip element are folded into parallel planes with those flanges connected by the strip element facing one another, the winding wire is arranged within the winding space of one coil former, is secured on the securing means and is then arranged within the winding space of the other coil former whilst retaining the same direction of winding rotation, and the coil formers are thereupon folded into a position in which the unconnected flanges are adjacent one another and those flanges connected by the strip element are more remote from one another, and are pushed on to the pole pieces of the pole assembly.

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. case, and the connecting wire sections for the excitation windings are immobilisable by means of straps 10. In Fig. 7, the securing means comprises two adjacent tab-like extensions 17 which bear resiliently against each other at their extremities and between them hold fast the wire section 15. WHAT WE CLAIM IS:

1. A shaded-pole motor comprising a pole assembly surrounded by a yoke, wherein the pole assembly has arranged thereon at least one pair of coil formers of insulating material which receive the excitation windings, each coil former having a first end flange adjacent the yoke and a second end flange remote from the yoke, and the said first end flanges of the or each pair of coil formers being interconnected by a bendable strip element, the strip element having means for securing a portion of wire connecting the excitation windings received by the respective ones of said pair of coil formers.