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JOHN M HOPWOOD

Overview
  • Total Patents
    62
About

JOHN M HOPWOOD has a total of 62 patent applications. Its first patent ever was published in 1917. It filed its patents most often in United States and Canada. Its main competitors in its focus markets thermal processes, machines and control are CASH A W CO, SMOOT CHARLES H and A P CONTROLS CORP.

Patent filings in countries

World map showing JOHN M HOPWOODs patent filings in countries
# Country Total Patents
#1 United States 60
#2 Canada 2

Patent filings per year

Chart showing JOHN M HOPWOODs patent filings per year from 1900 to 2020

Top inventors

# Name Total Patents
#1 Peebles Thomas A 15
#2 Donaldson Jr Robert R 7
#3 Smith George W 7
#4 Donaldson Robert R 6
#5 Brown Francis H 5
#6 Hall Ralph E 5
#7 Markson Alfred A 3
#8 Otto Harry A 3
#9 Specht James E 3
#10 Butzler Edward W 3

Latest patents

Publication Filing date Title
US2432705A Power unit
US2444358A Apparatus for measuring the state of compression of a liquid in a liquid vapor phasesystem
US2404937A System of control for pulverizer mills
US2339024A Pneumatic power cylinder and means for preventing over-travel of its piston
US2404951A System for the remote control of internal-combustion engines and clutches employed in ship propulsion
US2349329A Control system
US2304783A Pressure responsive ratio relay
US2357318A Pressure-actuated valve and vibration damping means therefor
US2304782A Pressure-responsive device
US2315665A Feed water control system for boiler furnaces
US2290125A Regulating apparatus and method
US2200907A Dishwashing machine
US2251019A Combustion control system
US2220837A Combustion control system
US2212125A Control system for pulverizer mills
US2130417A Apparatus for feeding water conditioning chemicals direct to boilers
US2104221A Control system for furnaces
US2149390A Pressure regulating device
US2136114A Control system for steam refrigerating systems
US2100460A Electric gauge and method for controlling the current output of grid controlled glow discharge tubes