Abstract: A head drum assembly for use in a tape recorder includes a holder of a general circular shape having a center hole through which a flange is fitted, a plurality of bosses on top thereof. Each of the bosses is provided with an assembling hole. The head drum assembly further includes a plurality of connectors. Each of the connectors has a body provided with a pair of posts insertable into the assembling hole for allowing the body to be maintained on the holder, a terminal plate for elastically contacting the video head and for elastically contacting the lower transformer. The terminal plate is integrally formed with the body.

Abstract: A head drum assembly for use in a video cassette recorder includes a stationary drum, a supporting shaft fixedly fitted into the stationary drum, a rotary drum mounted around an upper portion of the supporting shaft, an upper and a lower bearing for rotatable supporting the rotary drum. The stationary drum is provided with a bearing cavity having a sliding surface formed at a predetermined angle of inclination to a main frame of the video cassette recorder. In particular, the lower bearing mounted to rotate together with the rotary drum is lubricated by an oil lubricant retained in the bearing cavity, and includes pumping vanes for pumping the oil lubricant in such a way that the oil lubricant is uniformly distributed between the sliding surface and one surface of the lower bearing being in contact with the sliding surface.

Abstract: A head drum assembly for use in a video cassette recorder includes a stationary drum, a rotary shaft rotatably fitted into the stationary drum, a rotary drum closely fitted onto the rotary shaft, a lower bearing fitted into a lower portion of the stationary drum and an upper bearing fitted into an upper portion of the stationary drum. Herein, the upper bearing includes a top surface facing the rotary drum and an inner peripheral surface, facing the rotary shaft. The top surface is provided with a plurality of building-up grooves for retaining an oil for lubricating the upper bearing and the inner peripheral surface is provided with an oil guiding groove for guiding the oil retained on the inner peripheral surface onto the building-up groove of the top surface during rotation of the rotary shaft.

Abstract: An apparatus for testing wear-resistance of a pinch roller comprises a base provided with at least one post; a drum rotatably mounted on the base, wherein a tape is wound around an circumferential surface thereof; a driving motor; a tape holding member and a blind hole which is formed on the drum, the tape holding member being tightly inserted into the blind hole while the tape is tightened to hold the tape tightened; and a pinch roller holder pivotally mounted on the base, wherein a pinch roller to be tested is rotatably mounted on one end portion thereof and the other end portion is selectively connected to the post through an elastic member, thereby allow the pinch roller to resiliently press the tape against the drum.