Hitachi Telecom Technologies, Ltd
61Patents
1Active
61Granted
35Portfolio score
Filing activity: Mar 25, 1988 → Feb 23, 2004 · 1 expiring within 5 years
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4961217A | Personal-servicing communication system | Emerging Cross-Sectional Technologies | 43 | Expired |
| US6122292A | Dynamic band allocation system | Electricity | 35 | Expired |
| US5471525A | Line status display system for telephone exchange system | Electricity | 29 | Expired |
| US6822962B1 | Virtual connection switching method and ATM switch | Electricity | 20 | Expired |
| US6044136A | Telephone terminal and telephone exchange system accommodating the terminal | Physics | 9 | Expired |
| US5465292A | Trading telephone | Electricity | 7 | Expired |
| US5754642A | Telephone terminal having multiple handsets | Electricity | 7 | Expired |
| US5441814A | Method for use of preflux, printed wiring board, and method for production thereof | Emerging Cross-Sectional Technologies | 7 | Expired |
| US6345054B1 | Cell relay communication method, cell relay communication system and cell relay communication equipment | Electricity | 6 | Expired |
| US5602722A | Electric appliance, its assembling method, and its housing structure | Electricity | 5 | Expired |
| US5404398A | Telephone exchange system | Electricity | 5 | Expired |
| US6408055B1 | Electronic mail pop-up control system | Electricity | 5 | Expired |
| US5581446A | Housing structure of electric appliance and disassembling method thereof | Electricity | 4 | Expired |
| US5905551A | Electric appliance, its assembling method, and its housing structure | Electricity | 4 | Expired |
| US6031902A | Dealing communication system | Electricity | 4 | Expired |
| US5461376A | Panel unit of dealing board | Electricity | 4 | Expired |
| US5478607A | Method for use of preflux, printed wiring board, and method for production thereof | Emerging Cross-Sectional Technologies | 4 | Expired |
| US7099456B2 | Call center system | Emerging Cross-Sectional Technologies | 4 | Expired |
| USD421423S | Card reading-writing device with modem | General | 3 | Expired |
| US6141343A | Channel division control equipment of the | Electricity | 3 | Expired |
| US5461377A | Panel unit of dealing board | Electricity | 3 | Expired |
| US5651061A | Telephone exchange system | Electricity | 3 | Expired |
| US5594625A | Electric appliance, its assembling method, and its housing structure | Electricity | 2 | Expired |
| US5838402A | Electric appliance, its assembling method, and its housing structure | Electricity | 2 | Expired |
| US6192047A | Time division multiple equipment | Electricity | 2 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.