Floating device for information disc apparatus

A floating device comprising in combination:

• a. a floating surface providing a basis for floatation, and comprising a surface of an information medium having at least one of the characteristics of, information recording and reproduction;
• b. a fixing member provided in confrontation to said floating surface;
• c. a movable member held by said fixing member in such a manner that the distance between said movable member and said floating surface is variable;
• d. a floating body having a buoyancy with respect to said floating surface;
• e. an information element mounted on said floating body to perform at least one of the functions of, information recording and reproduction, with respect to the surface of said information medium;
• f. a resilient member which supports resiliently said floating body at the one side of said movable member facing said floating surface;
• g. shifting means provided at at least one of, said fixing member and said movable member, for varying the distance between said movable member, for varying the distance between said movable member and said floating surface;
• h. detecting means mounted on at least one of, said movable member and said floating body, for detecting the relative position of said floating body with respect to said movable member;
• and
• i. control means which causes said movable member to separate from said floating surface by means of said shifting member, when said floating body has the least or no buoyancy, and also causes said movable member to shift toward said floating surface by means of said shifting means until the relative distance between the movable member and the floating body based on the detected output from said detecting means reaches a predetermined value, when said floating body has buoyancy.

A floating device comprising in combination:

• a. a floating surface providing a basis for floatation, and comprising a surface of a disc-shaped recording medium, on which information may be optically written;
• b. means for rotating said disc-shaped floating surface;
• c. a fixing member provided in confrontation to said floating surface;
• d. a movable member held by said fixing member in such a manner that the distance between said movable member and said floating surface is variable;
• e. a floating body provided on the one side thereof facing said floating surface with at least one floating shoe which is floatable with a certain space interval being maintained with respect to said floating surface by creation of a high pneumatic pressure at the one side thereof facing toward said floating surface;
• f. a resilient member which spports resiliently said floating body at the one side of said movable member facing said floating surface, said resilient member causing said floating body to lower when said floating body has no buoyancy, and imparting to said floating body a resilient force so as to resiliently urge said floating body toward said floating surface;
• g. shifting means provided at at least one of, said fixing member and said movable member, for varying the distance between said movable member and said floating surface;
• h. detecting means mounted on at least one of, said movable member and said floating body for detecting a relative position of said floating body with respect to said movable member, said relative position between said movable member and said floating body corresponding to the amount of deflection of said resilient body, or a resilient force to urge said floating body toward said floating surface;
• i. an optical system mounted on said floating body for writing information in an optical manner with respect to said surface of the recording medium, said optical system converging a light signal modulated by said information onto said surface of the recording medium;
• j. control means which causes said movable member to separate from said floating surface by means of said shifting member, when said floating body has the least or no buoyancy, and also causes said movable member to shift toward said floating surface by means of said shifting means until the relative distance between the movable member and the floating body which is made known on the basis of a detected output from said detecting means reaches a predetermined value, i.e. while the amount of deflection of said resilient body reaches a predetermined amount, when said floating body has buoyancy, the floating quantity of said floating body reaching an expected value owing to a balance between buoyancy of said floating body and a resilient pressure force toaward said resilient body, when the amount of deflection of said resilient body reaches the predetermined value, whereby a converging point of an information light relative to the optical system mounted on said floating body substantially coincides with the surface of said recording medium;
• and
• k. means for forwarding said floating body in the radial direction of the disc-shaped recording medium, and forwarding said fixing member in the direction parallel to the radial direction of the disc so as to carry out optical recording of the information on said recording medium, while drawing a spiral track.