JPH0739684Y2 - Air conditioner for vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a vehicle air conditioner suitable for a vehicle provided with a hydraulic circuit and a refrigeration circuit, for example, a working vehicle such as a rough terrain crane vehicle. .

(Prior Art) Generally, in the case of a rough terrain crane vehicle in which the cabin rotates 360 °, unlike the ordinary vehicle, the engine cooling water circulating under the cabin cannot be introduced into the cabin, and the engine cooling water cannot be introduced. Cannot be used as a heat source for heating. Therefore, as an air conditioner for cooling and heating such a vehicle, one in which a heat pump type air conditioner is installed in a working vehicle has been proposed (Shokai 61-122462).

As shown in FIG. 2, this heat pump type air conditioner has a hydraulic circuit A and a refrigeration circuit B.

The hydraulic circuit A includes a hydraulic pump 11 that pumps the hydraulic oil in the oil tank 10, a hydraulic motor 12 that is driven by the pumped hydraulic oil, and a radiator 13 that releases the heat of the hydraulic oil that has flowed out from the hydraulic motor 12. The hydraulic oil flows to drive the hydraulic motor 12 as indicated by the one-dot chain line arrow in the figure. Further, the relief valve 14 adjusts the hydraulic pressure to the hydraulic motor 12.

The refrigeration circuit B includes a compressor 20, a four-way valve 21, heat exchangers 22, 23, 2
4. The receiver 25, the expansion valve 26, and the check valves 27a, 27b, 27c, and 27d. The compressor 20 is driven by the rotational force of the hydraulic motor 12 of the hydraulic circuit A, and the first heat exchanger 22
Is in thermal contact with the radiator 14 of the hydraulic circuit A. Also,
The second heat exchanger 23 is arranged in the air conditioning air passage 28 that communicates with the inside of the cabin.

Here, when performing the heating operation, as shown by the solid arrow, the refrigerant is compressor 20 → four-way valve 21 → second heat exchanger 23 → check valve 27a → receiver 25 → expansion valve 26 → first Heat exchanger 22 → Check valve 2
7b-> four-way valve 21-> compressor 20 circulates in sequence, and second heat exchanger 23
The inside of the cabin is heated by the heat radiation effect of.

On the other hand, when the cooling operation is performed, the refrigerant is compressed as indicated by the broken line arrow, that is, the compressor 20 → the four-way valve 21 → the third heat exchanger 24 → the check valve.
27c → liquid receiver 25 → expansion valve 26 → check valve 27d → second heat exchanger 23
→ The four-way valve 21 → The compressor 20 is circulated in sequence, and the inside of the cabin is cooled by the heat absorbing action of the second heat exchanger 23.

(Problems to be Solved by the Invention) However, in the above-described conventional vehicle air conditioner, cooling can be performed in the summer and heating in the winter, but dehumidifying heating required in the rainy season and the like is performed. However, the heat pump type air conditioner requires a large number of its components, which is disadvantageous in terms of cost.

In view of the above conventional problems, an object of the present invention is to provide a vehicle air conditioner that can perform cooling operation and heating operation without using a heat pump type air conditioner, and can also perform dehumidification heating operation. .

(Means for Solving the Problems) In order to solve the above problems, the present invention comprises a hydraulic circuit having a radiator on the downstream side of a hydraulic pump, and a refrigeration circuit in which an evaporator is arranged in an air conditioning air passage. In a vehicle air conditioner for driving a compressor of a refrigeration circuit by a rotational force of a hydraulic motor, a clutch mechanism for transmitting or releasing the rotational force of the hydraulic motor to the compressor is provided, and the radiator is the air conditioner. A relief valve, which is provided in the air passage, is located between the hydraulic pump and the radiator to cause a predetermined pressure difference in the hydraulic oil, and controls the flow rate of the hydraulic oil to the relief valve. And a switching means for restricting or canceling the flow of hydraulic oil to the variable throttle valve.

(Operation) According to the present invention, when the heating operation is performed, the clutch mechanism disconnects the hydraulic motor and the compressor, and the switching means causes the working oil to flow to the radiator side. At this time, the hydraulic oil generates heat by the frictional force in the pipeline of the hydraulic circuit, and is further heated by the resistance of the relief valve. The heated hydraulic oil is radiated by a radiator arranged in the air conditioning air passage to generate conditioned air for heating.

When performing the cooling operation, the clutch mechanism connects the hydraulic motor and the compressor, and the switching means regulates the flow of the hydraulic oil to the radiator. As a result, the compressor of the refrigeration circuit is driven, and the heat absorbing action of the evaporator produces conditioned air for cooling.

Furthermore, when performing the dehumidifying and heating operation, the clutch mechanism connects the hydraulic motor and the compressor to drive the hydraulic motor, and the switching means causes the working oil to flow to the radiator side.
As a result, hydraulic oil flows through the relief valve in the same manner as in the heating operation described above, and conditioned air for heating is generated by the heat radiation effect of the radiator. On the other hand, the air-conditioned air for cooling that has been dehumidified by the evaporator is generated by operating in the same manner as the above-described cooling operation. By passing both of the conditioned air through the air conditioning air passage, conditioned air for dehumidifying and heating is generated.

Furthermore, the flow rate of the hydraulic oil flowing through the relief valve is arbitrarily adjusted by the variable throttle valve during the heating and dehumidifying heating operations. As a result, the amount of heat generated by the relief valve is controlled, and the heating temperature and the dehumidifying heating temperature can be changed appropriately.

(Embodiment) FIGS. 1 and 3 show an embodiment of a vehicle air conditioner according to the present invention, and FIG. 1 is a circuit diagram showing a hydraulic circuit and a refrigeration circuit.

This hydraulic circuit C includes a hydraulic motor drive circuit C1 and a heat radiation circuit C2.
It consists of and. This hydraulic motor drive circuit C1
It has an oil tank 30, a hydraulic pump 31, and a hydraulic motor 32, and the hydraulic oil in the oil tank 30 is pumped up by the hydraulic pump 31, and the hydraulic motor 32 is driven by this pumped hydraulic oil. Incidentally, 33 is a first relief valve for adjusting the hydraulic pressure to the hydraulic motor 32.

The heat radiation circuit C2 has an oil tank 30, a hydraulic pump 34, a variable throttle valve 35, a second relief valve 36, a radiator 37, and a normally open solenoid valve (switching means) 38. When the solenoid valve 38 is open, the hydraulic fluid pumped up by the hydraulic pump 34 returns directly to the oil tank 30 via the solenoid valve 38, and when the solenoid valve 38 is closed. The working oil flows through the variable throttle valve 35 and the second relief valve 36 to the radiator 37. The hydraulic pumps 31 and 34 are driven by the vehicle engine.

Here, the variable throttle valve 35 controls the flow rate to the second relief valve 36, and the second relief valve 36 causes a constant pressure difference in the hydraulic oil between the inlet side and the outlet side, so that the hydraulic oil Heats up. This calorific value is calculated by the following formula. That is, H = 1.41 × Q × ΔP H: calorific value (kcal / h), Q: hydraulic oil flow rate (l / min), ΔP: pressure difference (kgf / cm ² ), 1.41: constant Therefore, the radiator 37 The heat radiation amount is proportional to the set pressure of the second relief valve 36 and the hydraulic oil flow rate of the variable throttle valve 35.

The refrigeration circuit D includes a compressor 40, a condenser 41, a liquid receiver 42, and an expansion valve.
43 and an evaporator 44 are sequentially connected, and the condenser 41 and the evaporator 44 are forcibly exchanged with each other by the blower fans 41a and 44a. Further, the compressor 40 is connected to the hydraulic motor 32 via a clutch mechanism 45.

FIG. 3 is a schematic configuration diagram showing a state in which the vehicle air conditioner according to the present embodiment is mounted on a rough terrain crane vehicle. That is, the air conditioning unit 51 is installed in the cabin 50, and the blower fan 44a, the evaporator 44, and the radiator 37 are installed in the air conditioning air passage 52 in the air conditioning unit 51. Further, this air conditioning air passage 52 can be switched between a heating air passage and a cooling air passage by a damper 53, and during heating and dehumidifying and heating, the air in the cabin 50 is changed by the air conditioning unit 51 as shown by the solid arrow. It is sucked from the suction port 54 and blows out into the cabin 50 through the evaporator 44 and the radiator 37, while at the time of cooling, it blows out into the cabin 50 only through the evaporator 44 as shown by a dashed arrow.

In this embodiment, when heating operation is performed in winter, the clutch mechanism 45 disconnects the hydraulic motor 32 and the compressor 40, closes the solenoid valve 38, and further drives the blower fan 44a.

At this time, in the hydraulic motor drive circuit C1, the hydraulic oil flows as shown by the broken line arrow in FIG. 1 to drive the hydraulic motor 32, but the compressor 40 is in a stopped state. On the other hand, the hydraulic oil pumped up by the hydraulic pump 34 circulates in the order of the variable throttle valve 35 → second relief valve 36 → radiator 37 → oil tank 30, as shown by the broken line arrow in FIG. Here, when the hydraulic oil passes through the second relief valve 36, a pressure difference is generated between the inlet side and the outlet side of the second relief valve 36, and the hydraulic oil generates heat. The heat of the hydraulic oil is released by the radiator 37 and heats the air in the air conditioning air passage 52 blown by the blower fan 44a. As a result, the interior of the cabin 50 is heated.

When performing the cooling operation in the summer, the clutch mechanism 45 connects the hydraulic motor 32 and the compressor 40, opens the solenoid valve 38, and drives the blower fans 41a and 44a. As a result, the hydraulic fluid pumped up by the hydraulic pump 31 circulates in the hydraulic motor 32 and drives the hydraulic motor 32, as indicated by the one-dot chain line arrow in FIG. The compressor 40 is driven by the rotational force of the hydraulic motor 32, and the refrigerant discharged from the compressor 40 is, as indicated by the solid line arrow, condenser 41 → receiver 42 → expansion valve 43 → evaporator 44 → compressor. Circulates sequentially with 40. As a result, the air in the air conditioning circuit 52 is cooled by the evaporator 44, and the cabin 50 is cooled. On the other hand, in the heat radiation circuit C2, the hydraulic oil pumped up by the hydraulic pump 34 is the solenoid valve.
Return to the oil tank 30 via 38.

When performing dehumidifying heating operation during the rainy season, etc., the clutch mechanism
The hydraulic motor 32 and the compressor 40 are connected by 45, the solenoid valve 38 is closed, and the blower fans 41a and 44a are driven. As a result, the hydraulic oil pumped up by the hydraulic pump 34 circulates as indicated by the broken line arrow as in the heating operation, and the radiator 37 heats the air in the air conditioning air passage 52.
Further, the refrigerant discharged from the compressor 40 circulates as shown by the solid line arrow in the same manner as during the cooling operation, and the evaporator 44 causes the air-conditioning air passage.
The air in 52 is dehumidified and cooled. By the dehumidifying cooling by the evaporator 44 and the heating by the radiator 37, the dehumidifying and heating of the cabin 50 is performed.

Further, during the heating operation and the dehumidifying heating operation described above, the amount of hydraulic oil flowing to the second relief valve 36 can be arbitrarily adjusted by the variable throttle valve 35. As a result, the amount of heat generated by the second relief valve 36 is controlled, and the heating temperature and the dehumidifying heating temperature can be changed appropriately.

(Effects of the Invention) As described above, according to the present invention, it is possible to cool and heat the inside of a vehicle without using a heat pump type air conditioner having a complicated structure as in the past, and also to dehumidify and heat the inside of the vehicle. It can be operated and can be air-conditioned to suit the rainy season. Further, the heating temperature and the dehumidifying heating temperature can be appropriately changed by adjusting the flow rate by the variable throttle valve, and the air conditioning at a desired temperature can be performed.

[Brief description of drawings]

1 and 3 show an embodiment of the present invention. FIG. 1 is a circuit diagram of a vehicle air conditioner, FIG. 2 is a circuit diagram of a conventional vehicle air conditioner, and FIG. [Fig. 2] is a schematic configuration diagram showing an installation state of a vehicle air conditioner. In the figure, 31, 34 ... Hydraulic pump, 32 ... Hydraulic motor, 35 ... Variable throttle valve, 36 ... Second relief valve, 37 ... Radiator, 38
... solenoid valve, 40 ... compressor, 44 ... evaporator, 45 ... clutch mechanism, 52 ... air conditioning air passage, C ... hydraulic circuit, D ... refrigeration circuit.

Claims (1)

[Scope of utility model registration request] 1. A hydraulic circuit having a radiator on the downstream side of a hydraulic pump, and a refrigeration circuit in which an evaporator is arranged in an air-conditioning air passage. The compressor of the refrigeration circuit is driven by the rotational force of a hydraulic motor. In a vehicle air conditioner, a clutch mechanism for transmitting or releasing the rotational force of the hydraulic motor to the compressor is provided, and the radiator is provided in the air conditioning air passage, and the hydraulic circuit has the hydraulic pressure. A relief valve that is located between the pump and the radiator to generate a predetermined pressure difference in the working oil, a variable throttle valve that controls the flow rate of the working oil to the relief valve, and a working oil to the variable throttle valve. A vehicle air conditioner characterized by being provided with a switching means for restricting or canceling the distribution of the air.