JPH0155393B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an engine-driven heat pump machine that performs air conditioning and heating by driving a compressor using an internal combustion engine that uses natural gas or gasoline as a heat source.

Conventional configurations and their problems Recently, conventional electric motors have been developed as a means of effectively utilizing primary energy and solving the difficulties of constructing new power plants and the peak demand for electricity in the summer. Engine-driven heat pump devices that perform cooling/heating or hot water heating operations by rotating a refrigerant compressor driven by an engine instead of a driven refrigerant compressor are attracting attention.

This engine-driven heat pump device converts fuel such as natural gas or gasoline into power using the engine and drives the compressor to operate the heat pump. It also collects exhaust heat from the engine and uses it for space heating and hot water supply, so it is not a primary energy source. It is characterized by extremely high efficiency compared to conventional electric heat pump machines.

When using this type of engine-driven heat pump device for domestic or commercial purposes, it is important to ensure that the engine starts reliably.

Normally, a starter motor is used to start the engine, but the capacity of this starter motor is 3.
A horsepower engine requires an electrical capacity of about 600 to 800 W, which uses valuable electrical energy for a short period of time, and the peak current flows several times the rated current during starting, so the starter should be as small as possible in terms of electrical equipment capacity. It is desirable that the motor be small. However, in order to stop the engine vibration and absorb shaft torque fluctuations, the engine is equipped with a flywheel that has a large moment of inertia.
This had the disadvantage that the starter motor for starting the engine was too large. Furthermore, if there is no electromagnetic clutch and the engine and compressor are directly connected,
Every time the engine is started by the starter motor, the compressor is rotated even if the engine is not running at all, putting a load on the bearings and sliding parts of the compressor. In addition, since the starting torque load on the compressor side is added, the capacity of the starter motor becomes large.

Furthermore, in the case of an engine-driven heat pump, it is necessary to start the engine reliably even when the outside temperature is below freezing. In this case, the viscosity of the oil sealed in the engine and compressor increases, making it difficult to start the starter motor The problem was that it was difficult to apply.

Purpose of the Invention The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to energize the starter motor to start the engine, but after the engine ignites and starts, the engine starts. Turn on the starter motor after the rotation speed reaches the specified speed.
The purpose is to improve the reliability of the compressor by turning it off and then energizing the electromagnetic clutch to drive the compressor, as well as to reduce the capacity of the starter motor and make it easier to start the engine.

Structure of the Invention To achieve this, the present invention connects an engine and a compressor via an electromagnetic clutch, provides a heat pump refrigerant circuit driven by the compressor, and provides a starter to start the engine, thereby controlling the indoor temperature. Three relay contacts are provided that are turned on by the operation of a detecting thermostat, and a rotation speed detector is provided to detect the rotation speed of the flywheel of the engine, and when the detected speed of the rotation speed detector reaches a set value or higher, , a switching contact that switches from a normally closed contact to a normally open contact is provided, and the normally closed contact of this switching contact, the first contact of the three relay contacts, and the relay coil of the starter motor are connected in series to a power source, and this switching The normally open contact of the contact, the second contact of the three relay contacts, and the relay coil of the electromagnetic clutch are connected in series to a power source, and the gas valve of the engine is connected through the third contact of the three relay contacts. This is a relay coil connected to a power source.

DESCRIPTION OF EMBODIMENTS Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

1 is an engine, 2 is a flywheel attached to the output shaft of the engine 1, and 3 is a starter motor. When energized, a gear 4 pops out and meshes with a gear 2' provided on the outer periphery of the flywheel 2 to start the engine 1. This is what starts the. Reference numeral 5 denotes a rubber joint that absorbs the difference between the output torque of the flywheel 2 and the required torque on the load side. An electromagnetic clutch 6 transmits the driving force of the engine 1 to the compressor 7 when energized. 8 is a heat pump refrigerant circuit, which performs heating and cooling by operating the compressor 7. 9 is the base of engine 1, 1
0 is a support spring, and 11 is a gas valve, which controls gas fuel supply to the engine 1. 12
is a rotational speed detector of the engine 1, which generates rotational pulses by a sensor (not shown) embedded in the flywheel 2.

13 is the power outlet, 14 is the operation switch,
15 is the relay coil of the starter motor 3, 16 is the relay coil of the electromagnetic clutch 6, and 17 is the gas valve 1.
The relay coil 18 is a switching contact that is controlled by opening and closing the contact 12' in response to the rotation speed detector 12. If the engine speed is 800 rpm or less, the contact 12' opens and the switching contact 18 switches the starter motor 3.
Closed to the normally closed contact on the relay coil 15 side at 800rpm
When this happens, the contact 12' closes and the switching contact 18 closes to the normally open contact on the relay coil 16 side of the electromagnetic clutch 6. 19a, 19b, 19c are each 3
The indoor electrical circuit 20 of the heat pump refrigerant circuit 8 at the first, second, and third contacts of the relay contacts.
It is designed to close in response to a thermostat 21 that issues an indoor cooling/heating operation command from a computer (details not shown).

Next, the operation will be explained with reference to FIG.
When the operation switch 14 is closed and heating and cooling from the indoor electrical circuit 20 of the heat pump refrigerant circuit 8 is requested, the thermostat 21 is turned on and the relay contacts 19a, 19b, and 19c are turned on.
Furthermore, since the switching contact 18 is closed on the side of the relay coil 15 of the starter motor 3, the gas valve 11 is opened at point A in FIG. The engine 1 is started by meshing with the gear 2'. As shown in Fig. 3, the rotational speed of the engine 1 overcomes the load torque at the time of starting (rotational load of the engine 1 and rotational load of the flywheel 2) and increases, and approaches a constant speed of about 500 rpm. At this time, the operating current of the starter motor 3 has already reached its rated value, and there is plenty of torque. After that, engine 1 starts (ignition starts) and the rotational speed of engine 1 further increases, and at time B point, approximately
When the rotation speed reaches 800 rpm or more, the contact 12' is closed by the rotation speed detector 12, the switching contact 18 is activated, and the relay coil 16 of the electromagnetic clutch 6 is closed, and the relay coil 15 of the starter motor 3 is de-energized. The gear 4 becomes disengaged and the starter motor 3
stops. However, since engine 1 is already running, engine 1 continues to increase its rotation. On the other hand, when the starter motor 3 is turned off, the coil 16 for the electromagnetic clutch 6 is energized, the engine 1 side and the compressor 7 side are connected, and the driving force of the engine 1 is transmitted to the compressor 7. At this time, the load on the compressor 7 side is applied to the engine 1 side by the electromagnetic clutch 6, but
The engine 1 is already rotating and accelerating, and there is almost no problem in terms of torque. Then, an arbitrary set rotation speed is reached (in this case, 1000 rpm), the compressor 7 is continuously rotated, and the heat pump refrigerant circuit 8 performs heating and cooling. After sufficient cooling and heating, when a cooling/heating stop instruction is output by the off signal of the thermostat 21 of the indoor electric circuit 20, the relay contacts 19a, 19b, and 19c open, and the relay coil 16 for the electromagnetic clutch 6 and By turning off the relay coil 17 for the gas valve 11, closing the gas valve 11, and disengaging the electromagnetic clutch 6, the engine 1 is turned off.
, and the compressor 7 is also stopped. Then, by closing the relay contact again, engine 1
operation will be resumed and heating and cooling operation will be repeated.

Effects of the Invention As is clear from the above description, according to the present invention, when starting an engine, the starter motor is started, the engine starts to ignite, detects a predetermined rotation speed, turns off the starter motor, and then turns off the electromagnetic clutch. Since electricity is applied to drive the compressor, the torque load on the starter motor at the time of starting is applied only to the engine side and not to the compressor side, so the starting current of the starter motor is reduced and the starter motor's torque load is applied. Miniaturization is possible. Furthermore, even if the viscosity of the oil sealed in the compressor increases when the outside air is cold, smooth startup is possible. Since the electromagnetic clutch is energized and the driving force of the engine is transmitted to the compressor only after the engine has started to ignite and reaches a predetermined rotational speed, no unnecessary load is placed on the bearings or sliding surfaces of the compressor. Since the load of the compressor is transmitted to the engine side by the electromagnetic clutch when the engine speed increases after the engine is ignited and started, it is possible to increase the speed of the compressor smoothly and effortlessly.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of an engine-driven heat pump machine according to an embodiment of the present invention, Fig. 2 is a control circuit diagram thereof, and Fig. 3 is a timing diagram showing the operation of the engine rotation speed, starter motor, and electromagnetic clutch. . 1...Engine, 2...Flywheel, 3...
...Starter motor, 6...Electromagnetic clutch, 7...
Compressor, 8... Heat pump refrigerant circuit, 11...
Gas valve, 12... Rotation speed detector, 15... Starter motor relay coil, 16... Electromagnetic clutch relay coil, 17... Gas valve relay coil, 18... Switching contact, 19... Relay contact, 2
0... Indoor electrical circuit, 21... Thermostat.

Claims (1)

[Claims] 1 The engine and the compressor are connected via an electromagnetic clutch, a heat pump refrigerant circuit driven by the compressor is provided, a starter motor is provided to start the engine, and the starter motor is turned on by the operation of a thermostat that detects the indoor temperature.3 A rotation speed detector is provided to detect the rotation speed of the flywheel of the engine, and when the detected speed of the rotation speed detector reaches a set value or more, the contact is switched from a normally closed contact to a normally open contact. A switching contact is provided, and the normally closed contact of this switching contact, the first contact of the three relay contacts, and the relay coil of the starter motor are connected in series to a power source, and the normally open contact of this switching contact and the first contact of the three relay contacts are connected in series to a power source. An engine-driven heat pump device in which a second contact of the contacts and a relay coil of the electromagnetic clutch are connected in series to a power source, and a relay coil of a gas valve of the engine is connected to a power source via a third contact of the three relay contacts. .