초록 ▼

A timber drying plant has a drying chamber through which air may be circulated by a fan in a circuit which includes a refrigerating unit. The refrigerant fluid circuit of the unit includes a dehumidification evaporator for outlet air and a condenser in the recycle air flow for returning to the latte

A timber drying plant has a drying chamber through which air may be circulated by a fan in a circuit which includes a refrigerating unit. The refrigerant fluid circuit of the unit includes a dehumidification evaporator for outlet air and a condenser in the recycle air flow for returning to the latter least part of the heat extracted by the evaporator. The refrigerant fluid circuit also includes an auxiliary evaporator with control valve means whereby the auxiliary evaporator can be inserted in said fluid circuit so that the refrigerating unit operates as a heat pump absorbing heat from the external atmosphere through the auxiliary evaporator. A supplementary evaporator may also be included in the refrigerating unit and is connectable in parallel with the auxiliary evaporator to increase the heat pump effect. In another position of the control valve means the auxiliary evaporator acts as a condenser in circuit with the dehumidification evaporator to reduce the heating of the recycled air.

대표청구항 ▼

In a drying plant for drying materials, particularly timber, by air circulation, comprising a drying chamber having air inlet and air outlet ports for the circulation of air in the chamber, and a refrigerating unit for the dehumidification of the air, said refrigerating unit comprising a refrigerant

In a drying plant for drying materials, particularly timber, by air circulation, comprising a drying chamber having air inlet and air outlet ports for the circulation of air in the chamber, and a refrigerating unit for the dehumidification of the air, said refrigerating unit comprising a refrigerant fluid circuit including a compressor, a fan for forcing inlet air into the drying chamber through the said inlet port, a dehumidification evaporator located in the outlet air flow from the outlet port, and a condenser located in the inlet air flow upstream of the inlet port to restore to the inlet air flow at least part of the heat extracted from the outlet air flow by said dehumidification evaporator, the improvement wherein the said refrigerating unit further comprises an auxiliary evaporator in said circuit exposed to the atmospheric air and valve means for switching said auxiliary evaporator into and out of the refrigerating fluid circuit whereby the refrigerating unit constitutes a heat pump absorbing heat from the atmospheric air when the auxiliary evaporator is switched into said circuit.