The present invention relates generally to electronic devices such as timepieces, pagers, radio receivers or the like and, particularly, to such devices in combination with wristbands manufactured to have integrally formed electrically conductive members.
Wrist worn electronic devices have limited space for mounting components. In such devices it is therefore desirable that the wristband segments receive selected components. In wristwatch-style radio receivers, for example, the wristband interior is designed to include electrically conductive plates or film which define an antenna around the wrist. Such wristband antennas are disclosed, for example, in Gaskill, U.S. Pat. No. 4,713,808, the disclosure of which is hereby incorporated by reference.
An antenna integrally formed within a wristband interior can be manufactured by means of injection molding. Two-stage injection molding has been employed, for example, to include an integral electrode in pulsemeter wristbands. To accurately position an electrode in a wristband, a first half-width slice of the wristband is injection-molded and an electrically conductive member placed on the inner side surface. The opposing half-width wristband slice is injection-molded integrally to the inner side surface of the first half segment so as to sandwich the conductive member between the first and second half-width slices.
Since a wristband must have sufficient flexibility to fit around the wrist, the electrode member should be thin so as not to compromise overall wristband flexibility. The flexibility of the electrode member has required two-stage injection molding. Single injection molding of wristbands having a flexible electrically conductive member have proven to be unsatisfactory insofar as the flexible member cannot resist the pressure of the injected molding material, thereby causing it to deform or move from a desired initial position and adversely affect desired wristband properties.
Two-stage injection molded wristbands also tend to exhibit weak bonding strength between the molded half segments and between the molded half segments and the inserted electrically conductive member. Such bonding difficulties lead to separation of the half segments from each other or separation of the electrically conductive member from the molded wristband segment. Hence, prior art wristbands manufactured by two-stage injection molding lack a long service life.
Accordingly, it is an object of the present invention to provide a method of manufacturing an electronic device wristband having an electrically conductive member securely retained in proper position by single injection molding.
Another object of the present invention is to provide a method of inserting and securely fixing an electrically conductive member in a molded wristband.
Still another object of the present invention is to provide an electronic device wristband formed by single injection molding and having an electrically conductive member properly positioned and securely bonded therein.