Patents Assigned to John Manufacturing Limited
  • Sensor switch
    Patent number: 5321390
    Abstract: In a portable device sensitive to a change in movement a switch inside the device has a movable slug which increases the electrical resistance in an electrical circuit when the device is disturbed. Such increase in resistance in the electrical circuit unbalances two inputs of a Schmitt trigger to cause an output of the Schmitt trigger to switch a switching transistor to cause an oscillator to drive an output transducer to give an alarm. A feedback loop limits the period for which the alarm is given and a delay circuit prevents an alarm being given when the device is initially energized and before the two inputs of the Schmitt trigger are balanced.
    Type: Grant
    Filed: September 28, 1992
    Date of Patent: June 14, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. K. Yuen
  • Multipurpose fluorescent lantern
    Patent number: D344602
    Type: Grant
    Filed: September 13, 1991
    Date of Patent: February 22, 1994
    Assignee: John Manufacturing Limited
    Inventor: John Se-Kit Yuen
  • Adjustable fluorescent lantern
    Patent number: D345810
    Type: Grant
    Filed: March 10, 1992
    Date of Patent: April 5, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Solar rechargeable flashlight
    Patent number: D346236
    Type: Grant
    Filed: March 11, 1992
    Date of Patent: April 19, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Night light
    Patent number: D348111
    Type: Grant
    Filed: April 1, 1992
    Date of Patent: June 21, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Solar rechargeable flashlight
    Patent number: D348740
    Type: Grant
    Filed: July 31, 1992
    Date of Patent: July 12, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Combined lamp and radio
    Patent number: D348882
    Type: Grant
    Filed: March 11, 1992
    Date of Patent: July 19, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S.-K. Yuen
  • Multi-purpose lantern
    Patent number: D348941
    Type: Grant
    Filed: July 14, 1992
    Date of Patent: July 19, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Combined cordless emergency power failure fluorescent lantern and flashlight
    Patent number: D348942
    Type: Grant
    Filed: August 17, 1992
    Date of Patent: July 19, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Combined fluorescent lamp and flashlight
    Patent number: D349776
    Type: Grant
    Filed: July 2, 1992
    Date of Patent: August 16, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se K. Yuen
  • Combined incandescent light and fluorescent lamp
    Patent number: D350210
    Type: Grant
    Filed: August 31, 1992
    Date of Patent: August 30, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se K. Yuen
  • Adjustable desk lamp
    Patent number: D350212
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: August 30, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se K. Yuen
  • Rechargeable emergency night light
    Patent number: D350407
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: September 6, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Adjustable fluorescent desk lamp
    Patent number: D350620
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: September 13, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se K. Yuen
  • Wall mounted lamp
    Patent number: D350621
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: September 13, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se K. Yuen
  • Combined radio and light
    Patent number: D350752
    Type: Grant
    Filed: April 7, 1992
    Date of Patent: September 20, 1994
    Assignee: John Manufacturing Limited
    Inventor: John S. Yuen
  • Combined ajustable desk lamp and radio
    Patent number: D351246
    Type: Grant
    Filed: February 8, 1993
    Date of Patent: October 4, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se-Kit Yuen
  • Adjustable desk lamp
    Patent number: D351248
    Type: Grant
    Filed: February 8, 1993
    Date of Patent: October 4, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se-Kit Yuen
  • Adjustable table lamp
    Patent number: D351677
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: October 18, 1994
    Assignee: John Manufacturing Limited
    Inventor: Se K. Yuen
  • Personal security alarm
    Patent number: D352474
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: November 15, 1994
    Assignee: John Manufacturing Limited
    Inventor: Yuen Se Kit