Prior art

To identify the most relevant prior art for US patent 9804819, I will examine the patent citations listed within the document.

The patent text for US9804819 lists the following patent citation as prior art:

• JPH09130173A

  • Full Citation: JPH09130173A (also referred to as Japanese Patent Application Laid-open No. JPH09130173)

  • Publication Date: May 16, 1997

  • Filing Date: November 2, 1995

  • Brief Description: This patent discloses an apparatus that automatically returns a volume key that has been inadvertently operated to a position at any given point in time. The patent itself states that "The known transceiver requires that, to set the volume again after the volume has been locked, the locked state be canceled and then the volume key be operated to thereby set the locked state. Thus, the known transceiver requires complicated operations for setting again the volume to be locked. Additionally, when the volume key is inadvertently operated in the locked state, the known transceiver outputs audio at an unintentional volume level as soon as the locked state is canceled."

  • Potential Anticipation (35 U.S.C. § 102):
    JPH09130173A addresses the general problem of preventing unintentional volume changes and providing a volume lock function. However, the description of US9804819 explicitly distinguishes itself from this prior art by stating that the "known transceiver" (referring to the prior art like JPH09130173) requires complicated operations to reset the volume after it has been locked and outputs audio at an unintentional volume level as soon as the locked state is canceled.

    Therefore, JPH09130173A would not appear to anticipate claims 1 or 8 of US9804819 under 35 U.S.C. § 102 because it lacks the specific inventive steps of US9804819, which include:

    • Switching from the locked state to a non-locked state for a specific period of time that starts when the operating value falls within a predetermined range based on the lock value and ends when a predetermined operating part is turned off.
    • Updating the lock value with the operating value and switching back to the locked state when the predetermined operating part is turned off after having been in the non-locked state.

    These features of US9804819 aim to overcome the "complicated operations" and "unintentional volume level" issues identified in prior art such as JPH09130173A.