← Back to Patent Explorer
US4454930A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for controlling an AC power elevator

Assignee: Mitsubishi Electric Corp
•
Filing: 1982-09-14
•
Granted: 1984-06-19
•
Expires: 2002-09-14
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An apparatus for controlling an AC powered elevator by rectifying a commercial AC power source into a direct current through a rectifier, converting the direct current into a variable frequency AC power through a main inverter, driving the AC motor by the thus converted AC power to operate the cage of the elevator, and sending the regenerated electric power back to the commercial AC power source via a regeneration inverter connected to the DC side of the main inverter when regeneration braking is applied to the electric motor. If the main inverter becomes defective, the main inverter is separated from the electric motor, the AC side of the regeneration inverter is connected to the motor, and the motor is operated by relying upon the regeneration inverter.

Inventors

  • 👤 Masami Nomura
  • 👤 Hiroyuki Ikejima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 10:45
CPC Classifications
H; H02; H02P; H02P23/00; H02P23/06; B; B66; B66B; B66B1/00

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 135 words
Apparatus for controlling an AC powered elevator having a case and being driven by an AC motor, which comprises: a rectifier the input of which connectes to a commercial AC power source for converting said AC power into a regulated DC voltage; a main inverter the input of which connects to the output of said rectifier for converting said DC voltage into variable frequency AC power for driving said AC motor; a regeneration inverter disconnectingly connected to; the output of said rectifier, said main inverter, said AC motor, and said commercial AC power source for sending the regenerated electric power from said AC motor rack to said commercial AC power source when regeneration braking is applied to said AC motor and for supplying AC power to said AC mtor when a defect detector is activated.
Claim 2
Dependent Claim 135 words
Apparatus for controlling an AC powered elevator having a case and being driven by an AC motor, which comprises: a rectifier the input of which connectes to a commercial AC power source for converting said AC power into a regulated DC voltage; a main inverter the input of which connects to the output of said rectifier for converting said DC voltage into variable frequency AC power for driving said AC motor; a regeneration inverter disconnectingly connected to; the output of said rectifier, said main inverter, said AC motor, and said commercial AC power source for sending the regenerated electric power from said AC motor rack to said commercial AC power source when regeneration braking is applied to said AC motor and for supplying AC power to said AC mtor when a defect detector is activated.
Claim 3
Dependent Claim 119 words
Apparatus for controlling an AC powered elevator as set forth in claim 1 wherein said appratus further comprises: a first control which is connected on the AC side of said main inverter, said contactor being normally closed under normal operation and opened when said defect detector is activated; a second contactor which is connected between the AC side of the regeneration inverter and said AC motor, said contacor being normally open under normal operation and closed when said defect detector is activated; a third contactor which is connected between the AC side of said rectifier and the AC side of said regeneration motor, said contactor being normally closed under normal operation and opened when said defect detector is activiated.
Claim 4
Dependent Claim 35 words
Apparatus for controlling an AC powered elevator as set fourth in claim 1 wherein: said regeneration inverter is of the separately-excited type consisting of thyristors; and said contactors are of an electromagnetic type of contactor.

References Cited (Backward Citations)

JPS5347971A Cited
US4376471A Cited
US4381457A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-06-19 1987-12-19 1988-06-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-06-19 1991-12-19 1992-06-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-06-19 1995-12-19 1996-06-19 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag