KR-20260066568-A - Defrost device and control method for agricultural work vehicles

KR20260066568AKR 20260066568 AKR20260066568 AKR 20260066568AKR-20260066568-A

Abstract

The present invention relates to a defrost device and control method for a cabin-type agricultural work vehicle equipped with an HVAC system, and more specifically, to a defrost device and control method for an agricultural work vehicle that, even when the defrost mode is activated during a cold start in a low-temperature winter environment, if the temperature of the engine room is lower than a certain temperature, secures a sufficient heat source for defrosting by closing the engine coolant valve to block the engine coolant flowing into the HVAC module, and subsequently performs defrosting when the temperature of the engine room becomes above a certain temperature. A defrost device and control method for a cabin-type agricultural work vehicle equipped with an HVAC system according to an embodiment of the present invention, wherein the HVAC system is equipped with a coolant valve on the inlet side of the heater core to control the amount of engine coolant flowing in from the engine, and the engine coolant discharged from the outlet of the heater core returns to the engine and circulates, and when a defrost mode is selected in the ACP and the indoor temperature is set to a maximum value, the coolant valve is opened when the temperature of the coolant on the engine room side is higher than the set temperature, thereby allowing the coolant to flow into the heater core.

Inventors

고광호
김동인

Assignees

주식회사 대동

Dates

Publication Date: 20260512
Application Date: 20241104

Claims (9)

In a defrosting device for a cabin-type agricultural work vehicle equipped with an HVAC system, The above HVAC system is, Compressor and condenser mounted in the engine room; An HVAC unit installed in the driver's cabin equipped with a heater core, evaporator, and blower; It includes an ACP installed in the cab to operate air conditioning modes and temperature settings, and A coolant valve is installed on the inlet side of the heater core to control the amount of engine coolant flowing in from the engine, and The engine coolant discharged from the outlet of the heater core returns to the engine and circulates, and When the defrost mode is selected in the above ACP and the indoor temperature is set to the maximum value, A defrost device for an agricultural work vehicle characterized in that the above-mentioned coolant valve opens when the temperature of the coolant on the engine room side is higher than the set temperature, thereby allowing the coolant to flow into the heater core.
In paragraph 1, The above HVAC unit is mounted under the driver's seat of the agricultural work vehicle, and A defrost device for an agricultural work vehicle, characterized in that the above HVAC unit has an air outlet, a heater core, an evaporator, a blower, and an air inlet arranged in sequence from the front side of the vehicle.
In paragraph 2, The air inlet of the above HVAC unit consists of an indoor air inlet on the rear upper surface of the HVAC unit and an outdoor air inlet on the rear side of the HVAC unit, and The above indoor air inlet is connected to an indoor air inlet duct connected to the rear side of the driver's cabin to introduce indoor air, and A defrost device for an agricultural work vehicle characterized in that the above-mentioned outdoor air inlet is connected to an outdoor air inlet duct connected to the outside side of the driver's cab to introduce outdoor air.
In paragraph 2, A defrost device for an agricultural work vehicle characterized in that an air discharge duct is connected to the air discharge port of the above HVAC unit, a defrost duct is connected to one end of the lower side of the windshield glass of the above air discharge duct, and the above air discharge duct is installed along the floor below the driver's cab.
In paragraph 1, A defrost device for an agricultural work vehicle, characterized in that the opening amount of the above-mentioned coolant valve is determined by an electric actuator disposed on the side of the HVAC unit and a link that transmits the rotational force of the electric actuator.
Compressor and condenser mounted in the engine room; An HVAC unit installed in the driver's cabin equipped with a heater core, evaporator, and blower; ACP installed in the driver's cab to operate air conditioning modes and temperature settings; The inlet side of the heater core includes a coolant valve for controlling the amount of engine coolant flowing in from the engine. A method for controlling a defrost device of a cabin-type agricultural work vehicle equipped with an HVAC system, A step of determining whether the defrost mode is selected in the above ACP and whether the ACP selected temperature is set to a maximum value; Step to count elapsed time; A step for determining whether the engine room coolant temperature is higher than the set temperature; If the engine room coolant temperature is higher than the set temperature, A control method for a defrost device of an agricultural work vehicle comprising the step of opening the coolant valve to an opening amount corresponding to the ACP selected temperature.
In paragraph 6, In the step of determining whether the engine room side coolant temperature is higher than the set temperature, if the engine room side coolant temperature is lower than the set temperature, Next, a step of determining whether the elapsed time has exceeded the set time; and A control method for a defrost device of an agricultural work vehicle comprising the step of closing the coolant valve when the above elapsed time has not exceeded the set time.
In Paragraph 7, A control method for a defrost device of an agricultural work vehicle that performs the step of activating FAIL/SAFE mode when the above elapsed time exceeds the set time.
In paragraph 8, The above FAIL/SAFE mode is a control method for a defrost device of an agricultural work vehicle that determines a sensor failure if the engine room side coolant temperature data received by the ACP does not exceed a set temperature for 10 minutes or more, and controls the coolant valve with a feedback value corresponding to the ACP selected temperature.

Description

Defrost device and control method for agricultural work vehicles The present invention relates to a defrost device and control method for an agricultural work vehicle equipped with an HVAC system, and more specifically, to a defrost device and control method for an agricultural work vehicle that, even when the defrost mode is activated during a cold start in a low-temperature winter environment, if the temperature of the engine room is lower than a certain temperature, secures a sufficient heat source for defrosting by closing the engine coolant valve to block the engine coolant flowing into the HVAC module, and subsequently performs defrosting when the temperature of the engine room becomes above a certain temperature. Agricultural work vehicles, known as 'tractors,' share similar driving principles with conventional automobiles; however, they differ significantly in structural details because they are all-weather vehicles utilized for various types of cultivation depending on working conditions and environments. In other words, they are designed to possess structures and power output characteristics advantageous for diverse tasks, enabling them to perform various types of work depending on their intended use. Meanwhile, conventional agricultural work vehicles were designed with the driver's cab, containing the driver's seat, instrument panel, and steering wheel, exposed to the outside. However, due to the recent trend of agricultural work vehicles becoming larger and more high-spec, models featuring a transparent glass box-shaped cabin are being released to protect the driver's seat from the external environment, improve quietness, and ensure a more comfortable and safe driving environment. Work vehicles with such a cabin structure are commonly referred to as "cabin-type work vehicles." In addition, the driver's cab of a cabin-type agricultural work vehicle is equipped with an HVAC (heating ventilation air conditioning) system to ensure a comfortable working environment. The HVAC system is largely composed of an HVAC unit equipped with a heater core, evaporator, and blower, a compressor and condenser located in the engine room, and an ACP (aircon control panel) located in the driver's cab that allows for the operation of air conditioning modes and temperature settings. In a cabin-type agricultural work vehicle, the HVAC unit is installed in the ceiling of the cab or inside the control panel case at the front of the cab, where the steering wheel, meter panel, etc. are mounted. When the HVAC unit is installed in the ceiling of the cab or on the interior roof, the overall height of the cab must be increased to secure headroom and installation space for the HVAC unit, which may cause problems with vehicle stability. On the other hand, when the HVAC unit is installed inside the driver panel case, the overall height of the tractor can be lowered, which increases vehicle stability, but since the HVAC unit must be placed in addition to the existing structure, package design becomes very difficult and assembly is poor. In addition, conventional HVAC systems installed in cabin-type agricultural work vehicles have a problem in that defrosting performance deteriorates in cryogenic environments, so frost on the front windshield glass is not removed for a long time after the operator starts the work vehicle. FIG. 1 is a perspective view of the entire system of a defrost device for an agricultural work vehicle according to an embodiment of the present invention. FIG. 2 is a drawing showing the ACP of an agricultural work vehicle according to an embodiment of the present invention. FIG. 3 is a perspective view showing the arrangement of components inside an HVAC unit constituting a defrost device of an agricultural work vehicle according to an embodiment of the present invention. FIG. 4 is an external perspective view of an HVAC unit constituting a defrost device of an agricultural work vehicle according to an embodiment of the present invention. FIG. 5 is a side view of an HVAC unit constituting a defrost device of an agricultural work vehicle according to an embodiment of the present invention. FIG. 6 is a control flowchart showing a control method for a defrost device of an agricultural work vehicle according to an embodiment of the present invention. Preferred embodiments of the present invention will be described below. In describing the present invention, the terms used in the specification below are used merely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. Furthermore, terms such as “comprising” or “having” in this specification are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers,