Cold weather starting control means for refrigerating systems

Claim 2

In a refrigerating system comprising a motor driven compressor, a condenser and an evaporator, a compressor controlling circuit comprising first switch means having an open condition effective to open said circuit and deenergize said compressor in response to relatively low pressure in said refrigerating system and second switch means having a closed condition for shunting said first switch means to complete said compressor controlling circuit when said first switch means is open, electric timer means energizable at the initiation of a refrigeration cycle to actuate said second switch means to said closed condition and after a given period to reopen said second switch means, and timer controlling means for controlling energization of said timer means in response to the ambient temperature of said condenser, said timer controlling means comprising a switch having a first condition for enabling energization of said electric timer means upon initiation of a refrigeration cycle when ambient temperature is below a given value and a second condition for preventing operation of said timer means upon initiation of a refrigeration cycle when ambient temperature is above said value.

Claim 3

A refrigerating system as defined in claim 1 further characterized by said compressor controlling circuit including a third switch means responsive to temperature produced by operation of said refrigerating system and in series with said timer means.

Claim 4

A system as claimed in claim 1 wherein said switch effects operation of a condenser cooling fan in said second condition.

Claim 5

A system as claimed in claim 1 further comprising condenser cooling fan means for directing a flow of cooling air to the condenser in relation to sensed condenser temperature independently of the condition of said switch.

Claim 6

In a refrigeration system having an evaporator disposed in a space to be cooled, a condenser exposed to atmospheric cooling air, a compressor, and a control arrangement for governing operation of the compressor, said control arrangement comprising: a. thermostatic switch means for initiating and terminating operation of the compressor in response to temperature of the space; b. pressure responsive switch means having an open condition for disabling said compressor when refrigerant pressure in the system is reduced below a predetermined level; c. timer controlled switch means having a closed condition for enabling operation of said compressor when said pressure responsive switch is in said open condition; d. said pressure responsive switch means and said timer controlled switch means electrically connected in parallel with each other and connected in series with said thermostatic switch means, said timer controlled switch means and said thermostatic switch means cooperable to enable operation of said compressor notwithstanding the condition of said pressure responsive switch means; e. electrically operated timer means for operating said timer controlled switch means, said timer means connected in a circuit with said thermostatic switch means so that when said thermostatic switch means operates to initiate operation of said compressor said timer means is energizable to operate said timer controlled switch means to the closed condition for a predetermined period of time; and, f. atmospheric temperature responsive switch means connected in a circuit with said timer means and said thermostatic switch means, said atmospheric temperature responsive switch means operable to permit energization of said timer means by said thermostatic switch means only when atmospheric temperatures are less than a predetermined relatively low temperature.

Claim 7

In a refrigeration system having an evaporator disposed in a space to be cooled, a condenser exposed to atmospheric cooling air, a compressor, and a control arrangement for governing operation of the compressor, said control arrangement comprising: a. thermostatic switch means for initiating and terminating operation of the compressor in response to temperature of the space; b. pressure responsive switch means having an open condition for disabling said compressor when refrigerant pressure in the system is reduced below a predetermined level; c. timer controlled switch means having a closed condition for enabling operation of said compressor when said pressure responsive switch is in said open condition; d. said pressure responsive switch means and said timer controlled switch means electrically connected in parallel with each other and connected in series with said thermostatic switch means, said timer controlled switch means and said thermostatic switch means cooperable to enable operation of said compressor notwithstanding the condition of said pressure responsive switch means; e. electrically operated timer means for operating said timer controlled switch means, said timer means connected in a circuit with said thermostatic switch means so that when said thermostatic switch means operates to initiate operation of said compressor said timer means is energizable to operate said timer controlled switch means to the closed condition for a predetermined period of time; and, f. atmospheric temperature responsive switch means connected in a circuit with said timer means and said thermostatic switch means, said atmospheric temperature responsive switch means operable to permit energization of said timer means by said thermostatic switch means only when atmospheric temperatures are less than a predetermined relatively low temperature.

Claim 8

The system claimed in claim 5 further including a condenser cooling means and wherein said atmospheric temperature responsive switch means is effective to render said condenser cooling means effective in response to sensed atmospheric temperatures above a predetermined lEvel.

Claim 9

The system claimed in claim 6 further comprising a condenser cooling fan and a fan speed control for operating said cooling fan in response to temperature of said condenser whereby heat is dissipated from said condenser by said cooling fan as a function of condenser temperature, said condenser cooling fan operable independently of said timer means so that the temperature of said condenser is controlled while said timer controlled switch means is in the closed condition.