outer circumferences of the respective second coil is enclosed and in contact with outer circumference of at least three first coils and wherein cross sectional area of the second coil is smaller than that of the first coil and wherein the outer circumference of the at least three first coils are in contact each other application_number US 84797210 A description reference will now be made in detail to various embodiments of the present invention s examples of which are illustrated in the accompanying drawings and described below while the invention s will be described in conjunction with exemplary embodiments it will be understood that present description is not intended to limit the invention s to those exemplary embodiments on the contrary the invention s is are intended to cover not only the exemplary embodiments but also various alternatives modifications equivalents and other embodiments which may be included within the spirit and scope of the invention as defined by the appended claims an exemplary embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings fig1 is a cross sectional view of a water pump of clutch type to which a coil according to an exemplary embodiment of the present invention is applied as shown in fig1 a water pump of.