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PCE
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DIFF Subgroup
H04M 1/31

by interrupting current to generate trains of pulses; by periodically opening and closing contacts to generate trains of pulses

Introduced: July 1974

Full Title

Full titles differ between systems:

IPC:

Substation equipment, e.g. for use by subscribers > Devices for calling a subscriber > Devices which can set up and transmit only one digit at a time > by interrupting current to generate trains of pulses; by periodically opening and closing contacts to generate trains of pulses

CPC:

Substation equipment, e.g. for use by subscribers (subscriber services or facilities provided at exchanges H04M3/00; prepayment telephone coin boxes H04M17/00; current supply arrangements H04M19/08) > Devices for calling a subscriber (H04M1/66 takes precedence) > Devices which can set up and transmit only one digit at a time > by interrupting current to generate trains of pulses; by periodically opening and closing contacts to generate trains of pulses

Of 6 combined children, 5 exist in both systems.

1 codes are CPC-only extensions.

1 shared codes have differing titles between IPC and CPC.

Child Classifications

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  • H04M 1/312 CPC only CPC only
  • H04M 1/315 Clutches; Spring assemblies; Speed regulators, e.g. centrifugal brakes (H04M1/32 – H04M1/40 take precedence) since 1980 IPC+CPC Available in IPC and CPC
  • H04M 1/32 Locking setting devices during transmission to prevent interference by user IPC+CPC Available in IPC and CPC
  • H04M 1/34 Lost-motion or other arrangements for ensuring a pause between successive digit transmissions IPC+CPC Available in IPC and CPC
  • H04M 1/38 Pulses transmitted by a movement variably limited by the setting of a stop IPC+CPC Available in IPC and CPC
  • H04M 1/40 wherein the setting-operation short-circuits or open-circuits the transmitting mechanism during a variable part of a cycle IPC+CPC Available in IPC and CPC

Top Applicants

Top Applicants (IPC)

Class H04,2013–2023, worldwide · Source: EPO PATSTAT

  1. QUALCOMM US 97,396
  2. HUAWEI TECHNOLOGIES COMPANY CN 96,502
  3. SAMSUNG ELECTRONICS COMPANY KR 86,981
  4. TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 55,869
  5. HUAWEI TECHNOLOGIES COMPANY 55,349
  6. LG ELECTRONICS KR 53,649
  7. CANON 33,341
  8. SONY CORPORATION JP 32,761
  9. ZTE CORPORATION CN 32,274
  10. GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION 28,327

Top Applicants (CPC)

Class H04,2013–2023, worldwide · Source: EPO PATSTAT

  1. HUAWEI TECHNOLOGIES COMPANY CN 101,476
  2. QUALCOMM US 101,139
  3. SAMSUNG ELECTRONICS COMPANY KR 96,655
  4. TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 57,744
  5. LG ELECTRONICS KR 55,253
  6. HUAWEI TECHNOLOGIES COMPANY 54,181
  7. SONY CORPORATION JP 35,309
  8. ZTE CORPORATION CN 32,950
  9. INTEL CORPORATION US 27,533
  10. GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION CN 27,498