CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119 to Korean Application No. 10-2018-0121341 filed on Oct. 11, 2018, whose entire disclosure is hereby incorporated by reference.

BACKGROUND

1. Field

Embodiments relate to a liquid dispenser.

2. Background

A liquid dispenser may be generally classified as one of a storage tank-type dispenser or a direct-type dispenser. The storage tank-type dispenser stores purified water or other liquid in a storage tank and supplies the liquid from the storage tank when a user manipulates a discharge unit. In contrast, the direct-type dispenser does not have a storage tank and, instead, the direct-type dispenser filters raw water when the user manipulates the discharge unit and immediately supplies the filtered water to the user. By omitting the storage tank, the direct water-type dispenser may relatively compact and may save water in comparison to water storage tank-type dispenser.

The liquid dispenser may also provide liquid that is heated or cooled. For example, the liquid dispenser may be equipped with a heating and cooling system. The heating system is configured to generate heated water or other liquid by heating the liquid, and the cooling system is configured to generate chilled water by cooling the liquid.

One type of heater is an induction heater, and induction heaters have the advantage of the high energy efficiency and being able to rapidly and stably control the heating of a liquid. A power semiconductor element, such as a insulated-gate bipolar transistor (IGBT), a triode for alternating current (Triac), etc. may be used to control the power supply to induction heaters, but the power semiconductor element may have a switching loss and a conduction loss, causing heat generation in the power semiconductor element. Because the power semiconductor element may be destroyed when the generated heat exceeds an accepted operating temperature for the power semiconductor element, heating of the power semiconductor element may be controlled. Typically, a heat discharge plate may be used to lower the temperature of the power semiconductor element.

However, when a heater liquid is discharged continuously over an extended period of time, the temperatures of the power semiconductor element and the heat discharge plate may increase. When a temperature of the power semiconductor element and/or the heat discharge plate reaches a limit of an operating temperature range, the heater may be deactivated to prevent overheating, and the dispenser will be unable to form and discharge a heated liquid. As such, an improvement in the heat discharge structure of the power semiconductor element may enhance the continuous discharge capacity of hot water in the direct water-type liquid dispenser.

