Title:
HEAT PUMP TYPE AIR-CONDITIONER
Document Type and Number:
Japanese Patent JPH01169261
Kind Code:
A
Abstract:
PURPOSE:To eliminate the shortage of refrigerator oil without lowering a heating capacity, by installing a control device which is capable of controlling a rotational speed of an indoor fan motor so that the pressure in a compressor may change below a fixed value when a preheating operation comes to a halt. CONSTITUTION:When starting a heating operation, a microcomputer 15 is controlled by a signal transmitted from a temperature detection device 14 and a pressure detection device 12 of a compressor 1. When a detected temperature exceeds a predetermined value Tp, it is controlled that a signal is transmitted to an indoor fan drive unit 16 so that voltage Vo available during normal operation may be applied to an indoor fan motor 5, if the quantity of superheat at the outlet of the compressor 1 exceeds a predetermined value Ts, and if it fails to exceed the predetermined value Ts, the voltage will be raised by Vo. If the pressure change for a fixed time is smaller than a predetermined value DELTAP, the voltage of the indoor fan motor will be repeatedly increased by Vo under control until the quantity of superheat exceeds the predetermined value Ts. If it exceeds the predetermined value DELTAP, the application voltage will be reduced by Vo. It is therefore, possible to eliminate drastic pressure variation and prevent the shortage of refrigerator oil due to the foaming of the oil.
Inventors:
MATSUSHIMA HIROAKI
SAKAZUME AKIO
IWATA HIROSHI
SAKAZUME AKIO
IWATA HIROSHI
Application Number:
JP32697887A
Publication Date:
July 04, 1989
Filing Date:
December 25, 1987
Export Citation:
Assignee:
HITACHI LTD
International Classes:
F24F11/04; F25B1/00; F25B13/00; (IPC1-7): F24F11/04; F25B1/00; F25B13/00
Attorney, Agent or Firm:
Katsuo Ogawa (1 person outside)