Timer for heat-cool room air conditioner

• US 4,144,930 A
• Filed: 10/14/1977
• Issued: 03/20/1979
• Est. Priority Date: 10/14/1977
• Status: Expired due to Term

• Current Assignee: General Motors Corporation (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Ferdelman, Donald C.
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US05/842,277
• Time in Patent Office: 522 Days
• Field of Search: 165/12, 165/26, 165/27, 236/46 R, 62/231
• US Class Current: 165/238
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/67 Switching between heating and cooling modes
• CPC Class Codes: G05D 23/1904 variable in time
• CPC Class Codes: G05D 23/275 with sensing element expanding, contracting, or fusing in response to changes of temperature

Abstract

An improved heat-cool room air conditioner unit control system having an electric timer located at the control area with the timer including a timer motor which runs continuously. A multi-gang selector switch is arranged in the control circuit with timer contacts and a single pole-double throw relay contact such that the selector switch and relay will selectively operate the unit in either a timed cooling mode or an untimed demand heating mode.

Claims

1. A timed control circuit for a self-contained room air conditioner unit operable to selectively heat or cool air, the combination of a housing enclosing a compressor driven by a motor, a condenser, an evaporator connected in a refrigerant circuit and a fan driven by a multiple speed electric motor for circulating room air to be cooled into heat exchange relation with said evaporator;

said fan motor having low and high speed terminals, electric resistance heater means disposed between said fan and said evaporator for heating the circulating air, and in which said housing has a room-side section with a control area thereon;

an electric timer located at said control area, said timer including a timer motor and a timer switch having a fixed contact and a movable contact electrically connected in a control circuit, said timer including manually operable time preselector means to preset when said timer switch shall close and open by selecting start and stop times for selectively controlling the cooling time of said unit, said control circuit including first and second supply conductors adapted for connecting the compressor motor and the fan motor to a power source;

said timer motor connected between said first and second supply conductors whereby it runs continuously with said unit, a thermostat switch means connected to said first supply conductor and having first and second contacts operative to cycle said compressor on and off in response to the temperature of the circulating cooling air;

the improvement wherein a multi-position manual rotary control connected in said control circuit for selectively operating said unit including either a timed cooling mode or an untimed demand heating mode, a single pole-double throw relay connected in said control circuit having first and second fixed contacts and a movable contact, said relay first fixed contact and said timer movable contact connected to a first common terminal, said thermostatic switch first fixed contact connected to said compressor motor which is in turn connected to said first common terminal, said thermostatic switch first fixed contact connected to said compressor which is in turn connected to said first common terminal, said relay second fixed contact connected to said second supply conductor, said multiple selector switch means including at least first, second, third and fourth selector switches, said thermostatic switch means second fixed contact connected to said first multiple selector switch which is in turn selectively connected to one side of said heater means, said second multiple selector switch selectively connected to said first supply conductor having at least one selective contact connected to said fan motor which is in turn connected to the movable contact of said relay, said third multiple selector switch means having its first and second selective contact means connected to said second supply conductor, said first selector contact means of said third multiple selector switch means connected to one side of operating coil means of said relay and its second selective contact means connected to the other side of said heater means, said fourth multiple selector switch means having its selective contact means connected to said relay first fixed contact and one of its fixed contacts connected to the fixed contact of said timer switch, said timer switch fixed contact connected to said one side of said relay operating coil means and the other side of said relay connected to said first supply conductor, whereby when said rotary control switch is positioned in its heating mode said relay coil is deenergized causing said relay movable contact to contact said relay first fixed contact bypassing said timer switch enabling said fan motor to run continuously, and whereby when said rotary control switch is positioned in its cooling mode said relay coil is energized causing said relay movable contact to be moved into engagement with its second fixed contact enabling said timer switch contacts to be placed in series with said common terminal causing said unit to operate in its timed cooling mode for a predetermined time in accordance with the start and stop times preselected by said manually operable timer preselector.