JP2004003860A - Outdoor unit of engine heat pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem of a conventional control box arranging method wherein, in removing a control box for maintaining a component such as an electronic expansion valve back the box, a wire harness connected to each terminal in the control box must be removed, man-hour of reassembling is increased, and an assembling error often occurs. <P>SOLUTION: An outdoor unit 1 of an engine heat pump can be vertically divided into two parts, and the upper part is a heat exchange chamber 1a having a refrigerant system or a coolant system. A control box CB is disposed on the front surface in the heat exchange chamber 1a, the electronic expansion valve 39 or the like is disposed in the back part of the control box CB, and a long hole 41a of a longitudinally long shape is formed in the control box CB. When the control box CB is extracted forward, the control box can be slid forward in the long hole 41a. After sliding the control box CB forward, the control box CB can be rotated horizontally about the final part of the long hole 41a as a rotating axis on one vertical edge. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to the structure of an outdoor unit of an engine heat pump.

The engine heat pump is provided with an engine-driven compressor in an outdoor unit, and circulates compressed refrigerant between the outdoor unit and the indoor unit to perform indoor air conditioning. Conventionally, it is disclosed in Japanese Patent Application Laid-Open No. 5-306851.
In a conventional outdoor unit, the arrangement position of the control box is fixed, and when performing maintenance work on, for example, an electronic expansion valve in the machine, it is necessary to release bolts and remove the control box. there were.

Japanese Patent Application Laid-Open No. 5-306851

In the conventional control box arrangement method, when removing the control box when maintaining parts such as the electronic expansion valve behind the box, it is necessary to remove the wire harness connected to each terminal in the control box, The number of re-assembly steps is large, and there is a high possibility that wrong assembly will occur.

The present invention uses the following means to solve the above problems.
In the outdoor unit 1 of the engine heat pump, the outdoor unit 1 is divided into upper and lower parts, an upper part is a heat exchange chamber 1a in which a refrigerant system and a cooling water system are disposed, and a control box CB is disposed on a front surface in the heat exchange chamber 1a. The control box CB is provided with an electronic expansion valve 39, etc., at the back thereof, and the control box CB is provided with an elongated front-rear slot 41a. After the control box CB is slid forward in the long hole 41a, the control box CB is horizontally moved by using the last portion of the long hole 41a as a pivot point on one vertical side. This is an outdoor unit of an engine heat pump that is rotatable in a direction.

In this way, by making the control box slidable back and forth and rotatable in the horizontal direction about one vertical side as a rotation axis, when performing maintenance on members deeper than the box. Is slid forward and horizontally rotated about one vertical side to open the back of the box, and the box can be temporarily fixed at the rotated position. There is no need to remove the wire harness if there is enough wire capacity to move the wire harness.

Since the present invention is configured as described above, the following effects can be obtained.
Since the control box of the outdoor unit of the engine heat pump is configured as described in claim 1, the electrohydraulic parts such as the electronic expansion valve 39 located behind the control box at the time of storage by rotating the control box by sliding forward are stored. Can be opened to the front, making maintenance work easier than at the front.
In addition, it is very easy to move the control box when opening the front, and it is not necessary to remove the conventional fixed control box and carry it to another place. In the present invention, the wire harness extracting operation required for moving the control box to the control box can be performed by setting the wire to a length that can be moved to a position where the control box is finally fixed. Is unnecessary, and since the movement end position of the control box is not so far from the storage position, the length of the wire does not need to be so long, and the control box can be sufficiently stored.

Next, a configuration of the present invention will be described based on an embodiment shown in the accompanying drawings.
FIG. 1 is a front view of the engine heat pump in which the outdoor unit is opened to the front, FIG. 2 is a front view of the same state in which the control box is detached and the entire heat exchange chamber 1a is opened to the front, and FIG. FIG. 4 is a plan view showing an E / C unit mounting structure in an engine room 1b, FIG. 5 is a side view, FIG. 6 is a side view, and FIG. 7 is a conventional rectifier for starting an engine. And FIG. 8 is a side view of the transformer.

FIG. 9 is a plan view of an engine intake system showing a configuration in which a rectifier 28 of an engine starting transformer 27 is disposed at a suction port of an intake duct, FIG. 10 is a perspective view showing a room configuration in an outdoor unit, and FIG. 11 is a ventilation room 1c. 12, FIG. 13 is an internal plan view of the heat exchange chamber 1a, FIG. 13 is an internal side view thereof, FIG. 14 is a diagram showing a configuration in which a conventional direct connection pipe 48 is connected to a radiator outlet header 50, and FIG. It is a figure which shows the convection of the cooling water in the radiator exit header 50 and the radiator R in the structure of FIG.

FIG. 16 is a view showing a configuration in which the direct connection pipe 48 is connected to the cooling water pipe 38 on the downstream side of the radiator outlet header 50, and FIG. FIG. 18 shows a configuration in which a cooling water pipe 38 is branched, FIG. 18 shows a configuration in which a check valve 51 is provided in the configuration of FIG. 17, and FIG. 19 shows an internal configuration of a drain filter DF connected to an exhaust pipe. FIG. 20 is a refrigerant circuit diagram showing the refrigerant flow during heating, FIG. 21 is a refrigerant circuit diagram showing the refrigerant flow during cooling, and FIG. 22 is ON / OFF of the outdoor fan based on the relationship between the outside air temperature and the compression capacity. It is a graph which shows the boundary for control.

The internal configuration of the outdoor unit of the engine heat pump in a state where the front portion is opened from FIGS. 1 and 2 will be described.
The entire outdoor unit is covered with a frame 1, the inside of the unit is divided into upper and lower parts, and the upper part is a heat exchange chamber 1a in which a refrigerant system and a cooling water system are disposed. A waste heat recovery unit 36 and the like are piped inside, heat exchangers 34 and 34 are provided on the side, and outdoor fans 40 and 40 for heat exchange are provided on the top.
On the right side, a control box CB is disposed on the front surface as shown in FIG. 1, and the control box CB is moved as shown in FIG.

The lower part of the outdoor unit is further divided into two parts, the left side is an engine room 1b in which the engine E and the compressor C are disposed, and the right side is a liquid receiver 32 or the like, in order to avoid high heat radiated from the engine. It is a ventilation room 1c in which various electronic components and a ventilation fan 5 are disposed. FIG. 10 also shows the arrangement of the heat exchange room 1a, the engine room 1b, and the ventilation room 1c in the outdoor unit.

Here, the underfloor structure of the outdoor unit will be described with reference to FIGS.
At the lowermost part, mounting feet 2d are fixed to the underfloor member 2 to be placed on the floor, and are grounded on the floor at the position where the outdoor unit is provided.
The underfloor member 2 is press-moldable and easily configured, has an overall shape of a shallow dish, and is located on the left side, as shown in FIG. 3, at a position below the engine room 1b. , The upper part is covered, while, on the right side, an upper open part is provided to introduce the cooling air W from the ventilation fan 5 in the ventilation room into the internal cooling air duct chamber 2a. I can do it.

Above the underfloor member 2 having such a configuration, the engine room floor 3 is bolted to the left and the ventilation room floor 4 is bolted to the right. It can be installed with only bolts and no welding required.
When the floor materials 3 and 4 are attached in this manner, a double-floor underfloor structure having a space below the floor material is formed. Further, the flooring material 4 is provided with an inclined portion 4a having a communication hole formed in a lower left portion thereof, which faces an upper open portion of the floor plate member 2, and a ventilation fan 5 is provided on the inclined portion. 1 and 2, the cooling air W taken in by the ventilation fan 5 is introduced into the cooling air duct chamber 2a in the underfloor member 2 through the communication hole of the inclined portion 4a.

On the engine room floor 3, vibration isolating rubbers 6, 6,... Are bolted, and unit brackets 7, 7 for mounting an E / C unit including an engine E and a compressor C are arranged thereon.
In addition, as shown in FIG. 3, in the upper covering portion of the underfloor member 2 and the engine room flooring material 3, near the fixed position of the vibration isolating rubber 6, vibration isolating rubber cooling holes 2b and 3a, and E / C Belt cooling holes 2c and 3b are formed below the drive belt 9 made of rubber material and wound around the input pulley 10 of the compressor C from the output pulley 8 of the engine E of the unit. So that the air in the cooling air duct chamber 2a passes through the vibration isolating rubber cooling holes 2b and 3a and strikes the vibration isolating rubber 6 and also passes through the belt cooling holes 2c and 3b and strikes the drive belt 9. (Arrows in FIGS. 1 and 2).
Thus, by applying the cooling air, the deterioration of the anti-vibration rubber 6 and the drive belt 9 is suppressed. Further, the cooling air that has cooled the vibration isolating rubber 6 and the drive belt 9 further rises to cool the entire E / C unit, and isolates the engine room 1b from the heat exchange chamber 1a above it as shown in FIG. It is discharged to the heat exchange chamber 1a from the communication hole 1e provided in the horizontal partition.

By thus interposing the space consisting of the cooling air duct chamber 2a in the underfloor member 2 under the floor of the engine room, noise transmission to the floor can be suppressed, and a low-noise outdoor unit can be provided. Further, the structure of the underfloor member 2 is formed by press molding, and the underfloor structure can be formed by merely fastening the floor members 3 and 4 with bolts thereon, the number of welding points can be reduced, the cost can be reduced, and assembly is easy. .

Next, regarding the assembly structure of the E / C unit in the engine room 1b, the configuration of the unit bracket 7 will be described with reference to FIGS. The unit bracket 7 is a vertical plate material bent in an L shape in plan view and has the same shape in the upper and lower directions. Therefore, the two unit brackets 7.7 are inverted and connected to each other with bolts 11. As shown in FIG. 4, the bracket can be a U-shaped bracket in plan view.

The upper and lower ends of each unit bracket 7 are bent to form horizontal portions 7a, and cutout portions 7b, 7c into which bolts for attaching the vibration isolating rubber 6 are inserted. In a configuration in which the front and rear unit brackets 7, 7 are joined together, as shown in FIG. 4, the right end portions of the notch portions 7b, 7b and the left end portions of the lower horizontal portions 7a, 7a of both unit brackets 7, 7 are formed. The upper end of the anti-vibration rubber 6 is bolted to one of the cutouts 7c, 7c, and the three anti-vibration rubbers 6, 6.6 are combined and fixed to the lower portion of the unit bracket 7.7.

The E / C unit mounting configuration to the unit brackets 7, 7 will be described. First, an oil pan 12 is fixed to the lower part of the engine E, and the side surface of the oil pan 9 is located near the right end of the unit brackets 7, 7. A bolt is fixed to the side surface of the part with bolts 13.
A compressor C (a multi-compressor having two input pulleys 10 as shown in FIG. 6, that is, having two compressors arranged side by side) has a horizontal compressor bracket 14 at its upper end with bolts 15.15. One end of the compressor bracket 14 is fastened to the bracket 16 fixed to the upper horizontal portion 7a of one of the unit brackets 7 with bolts 17.

A U-shaped long hole bracket 18 is fixed to the upper end horizontal portion 7a of the unit bracket 7 on the opposite side, and bolts 19 are inserted into the long holes of the long hole bracket 18. The compressor bracket 14 is tightened. The compressor bracket 14 protrudes outward from the elongated hole bracket 18, and a tension bolt 20 for screwing and arranging a tension fitting 21 in a vertical direction is inserted into this portion. The compressor bolt is operated by operating the tension bolt 20. The bracket 14 is rotatable around bolts 17 screwed to the bracket 16 as a fulcrum, whereby the compressor C fixed to the compressor bracket 14 is rotated up and down, and the compressor output from the engine output pulley 8 The tension of the drive belt 9 wound around the C input pulley 10 is adjusted.

A method of removing the compressor C attached to the unit brackets 7, 7 will be described. First, as shown in FIGS. 4 and 5, wood chips are inserted into a gap between the oil pan 12 of the engine E and the engine room flooring 3. Chew 22. In this state, the front unit bracket 7 is removed. At this time, the E / C unit is supported by the wood piece 22 from below.
Next, the rear unit bracket 7 is removed. Thus, the E / C unit is detached from the unit brackets 7, 7, and the bolts 15, 15,... Are further removed from the compressor bracket 14, so that the compressor C can be removed.

In the engine room 1b to which the E / C unit is attached as described above, the intake ducts 23, 24, and 25 are disposed at the upper portion thereof as shown in FIG. 1 or FIG. A hose is connected between the intake duct 25 and the air cleaner AC, and a hose is further connected from the air cleaner AC to a mixer 26 attached to the engine E, and air is taken into the engine E.
The intake duct 23 faces the left side surface of the frame 1 and has an intake port. A transformer 27 for starting the engine E is arranged near the intake duct 23, and a rectifier 28 connected to the transformer is attached to the intake duct 23.

Conventionally, as shown in FIGS. 7 and 8, the rectifier 28 is directly attached to the transformer 27 for downsizing, and the transformer 27 is always provided at a position having a high cooling effect. Therefore, the heat generation of the transformer 27 and the rectifier 28 was not suppressed, and there was a problem in durability. Therefore, a large-capacity rectifier 28 had to be used.
However, in the present embodiment shown in FIG. 9, the rectifier 28 is attached to the intake duct 23, so that the air is constantly blown by the intake air and is cooled, the durability is increased, and there is no need to increase the capacity, and the cost is reduced.

As shown in FIGS. 12 and 13, an exhaust pipe 52 extends upward from the engine room 1b to the heat exchange chamber 1a, and the outside air intake port of the outdoor fan 40 passes through a drain filter DF. Is more exhausted. The drain filter DF is for neutralizing harmful substances in the exhaust, draining the same with water, and discharging the purified exhaust.
This configuration will be described with reference to FIG. 19. In an exhaust outer pipe 54 having an upper opening shape and an upper end diameter larger than a lower end diameter, an exhaust inner pipe 53 having a lower end connected to an exhaust pipe 52 is connected to the exhaust inner pipe 53. A pipe is introduced from the bottom of the outer pipe 54, and a drain outlet 54a is opened at the bottom of the exhaust outer pipe 54, and a drain outlet 54b is opened at a position near the lower end of the side surface.
In the exhaust outer pipe 54, the upper end of the exhaust inner pipe 53 is lower than the upper end position of the exhaust outer pipe 54. At a position slightly lower than the upper end of the exhaust inner pipe 53, a plurality of communication holes 55a Are provided, and are surrounded by a lower surface of the partition 55, an inner surface and a bottom upper surface of the exhaust outer tube 54, and an outer surface of the exhaust inner tube 53. The room is filled with a neutralizing agent 56 (calcite (CaCO ₃ )).

In the drain filter DF having the above-described configuration, the process of drain separation in exhaust gas will be described. First, exhaust gas is introduced from the engine E of the outdoor unit into the exhaust pipe 53 via the exhaust pipe 52, When exhausted from the upper end of the exhaust gas 53, the moisture in the exhaust gas descends along the inner wall surface of the exhaust outer pipe 54, falls on the partition wall 55, and further enters the neutralizing agent 56 through the communication hole 55a. I do. The water neutralized by the neutralizing agent 56 is discharged from the drain outlet 54a or the drain outlet 54b.

The exhaust outer pipe 54 can be connected to a plurality of drain filters DF by fitting the bottom of another exhaust outer pipe 54 inside the upper end portion having a large diameter. Even if the capacity of each drain filter DF is constant, drain connection in a large volume exhaust gas can be performed by connecting a plurality of drain filters DF.
When a plurality of drain filters DF are connected in this way, they are connected upward. It is downstream for exhaust and upstream for drain. The drain outlet 54b of the drain filter DF is closed by the exhaust pipe 54 of the drain filter DF connected below, so that the drain does not leak. For this purpose, the drain outlet 54b is formed near the lower end of the side surface of the exhaust outer pipe 54.
In addition, the drain from the drain filter DF on the upper connection side flows into the drain filter DF on the lower connection side by opening the drain outlet 54a of the drain filter DF on the upper connection side without closing the plug, and is connected to the lowermost part. The drain can be discharged collectively from the drain outlet of the drain filter DF. Either of the drain outlets 54a and 54b may be selected as the drain outlet of the lowermost drain filter DF depending on the positional relationship of the outlets.

Next, the configuration inside the ventilation room 1c of the outdoor unit will be described with reference to FIGS.
A fin 1d having a horizontally long opening is formed on the front surface of the frame 1 at the portion of the ventilation room 1c, and outside air is introduced into the ventilation room 1c from this portion.
The inside of the ventilation room 1c is isolated from the engine room 1b by a partition wall 29, and is kept at a temperature substantially equal to the outside air temperature by the outside air sucked from the fin 1d. , A fuel gas pipe 30, a regulator 31, a liquid receiver 32, and an accumulator 33 are provided. In addition, various solenoid valves, each stop valve of a refrigerant system, a gas system, and a cooling water system, a sight glass SG And so on.
The ventilation fan 5 is provided at the lowermost portion, and introduces outside air introduced from the fins 1d into the cooling air duct chamber 2a in the underfloor member 2 as described above.

外 An outside air temperature sensor TS is provided near the fin 1d in the ventilation room 1c and on the suction side of the ventilation fan 5. The outside air temperature is a detection value necessary for setting heating or cooling in comparison with the room temperature.If the outside air temperature sensor S is provided at this portion, outside air is constantly sucked in. Since it is the part closest to the outside air and is further isolated from the engine room 1b, the error between the outside air temperature and the detected value is extremely small in any case.

Next, the configuration inside the heat exchange chamber 1a will be described with reference to FIGS.
On the side surface and the front and rear surfaces of the frame 1 forming the heat exchange chamber 1a, two heat exchangers 34 each having an L-shape in plan view are supported by a heat exchanger frame 35, and two heat exchangers 34 are provided. A refrigerant pipe is provided in the exchanger 34. A radiator R is also provided on the front surface in parallel with the heat exchanger 34.
A waste heat recovery unit 36 for recovering engine residual heat is disposed near the center of the front and rear of the upper part of the engine room 1b, and a cooling water pipe 38 provided with a cooling water pump 37 is provided in front of the waste heat recovery unit 36. The cooling water pipe 38 is introduced into the lower engine room 1b and is brought close to the engine E to cool the engine. Further, an electronic expansion valve 39 is interposed in a refrigerant pipe extending above the ventilation chamber 1c and introduced into the heat exchange chamber 1a. The upper end is open so that the outdoor fans 40 can introduce or radiate outside air.

Further, a control box CB is provided at a front portion above the ventilation room 1c in the heat exchange room 1a. The control box CB is movable as shown in FIG. 12, and this configuration will be described with reference to FIGS. 1, 2, and 12.
A box bracket 41 is fixedly provided on the right side of the control box CB, and front and rear elongated holes 41a are formed in the upper and lower surfaces of the box bracket 41.
Then, horizontal brackets 42 are provided vertically at the front end of a heat exchanger frame 35 that supports the heat exchanger 34 disposed on the right side surface of the frame 1, and the box bracket 41 is sandwiched from above and below. Bolts 43 are inserted into bolt holes of the brackets 42 and upper and lower holes 41a of the bracket 41 for the box.

In a state where the control box CB in a normal state is housed in the heat exchange chamber 1a (the state of FIG. 1), bolts 43 are inserted into the foremost portions of the long holes 41a of the box bracket 41, and the screw is inserted. On the other hand, a bolt hole is formed near the left end of the bottom of the control box CB, and a bracket 44 is horizontally fixed to the upper end of the partition wall 29 that separates the engine room 1b from the ventilation room 1c. The control box CB is fixed by inserting and bolting a bolt 45 into the bolt hole of the control box CB from the bolt hole of the bracket 44.

In order to perform maintenance work on the electronic expansion valve 39 and the like located behind the control box CB in the heat exchange chamber 1a, when the control box CB is to be removed to open the heat exchange chamber 1a, the bolt 45 is required. The control box CB is pulled forward by loosening the bolts 43, 43, and sliding the bolts 43, 43 in the elongated holes 41a, 41a.
Eventually, when the bolts 43 reach the last portion of the long holes 41a, the control box and the box bracket 41 are rotated forward with the bolts 43 as fulcrums. After the rotation, when the bolts 43 are tightened, the position where the control box CB is rotated, that is, the member such as the electronic expansion valve 39 which has been CB 'in FIG. 12 is opened to the state of FIG. Maintenance work can be performed more.

In the control box CB, wires from the respective solenoid valves and electronic expansion valves are connected via a wire harness. However, if the length of the wires is sufficiently long, the wires are slid forward and further turned. Even when moved to the moved CB 'position, there is no need to remove the wire harness.
That is, at the time of the maintenance work of the electronic expansion valve 39 and the like, the wire intermittent work is not required, and only the moving operation of the control box CB is required. Also, the length of the wire does not need to be so long as long as the wire is allowed to move to the moving position CB '.
If the control box CB is not such a movable type and is fixed to a storage position in the heat exchange chamber 1a with a bolt or the like, after the bolt is released during maintenance work, the control box CB is moved to a position other than the movable type. Or if it is necessary to keep it in another position, and if it is necessary to take the length of the wire so that the wire is not required, it becomes very long and cannot be stored in the outdoor unit. Work had to be done. Compared with this conventional one, by making the control box CB movable, the maintenance work can be remarkably facilitated.

Next, the piping configuration of the cooling water pipe between the heat exchanger 34 and the waste heat recovery unit 36 in the heat exchange chamber 1a will be described with reference to FIGS.
The cooling water Wa is introduced from the engine room 1b into the cylindrical waste heat recovery device 36 in which the refrigerant pipe 46 is fitted, and the cooling water Wa flows out from the waste heat recovery device 36 to the thermostat TH.
As shown in FIG. 13, the thermostat TH branches into a radiator introduction pipe 47 introduced into the radiator R, and a direct connection pipe 48 introduced into the cooling water pump 37 without passing through the radiator R. The radiator introduction pipe 47 is connected to a radiator inlet header 49, and the direct connection pipe 48 is connected to a cooling water pipe 38 extending from a radiator outlet header 50.

The thermostat TH detects the temperature of the cooling water Wa, and if the temperature is equal to or higher than a predetermined value, introduces the cooling water Wa into a radiator in the heat exchanger 34 to cool the cooling water. However, if the cooling water is excessively cooled, particularly during heating, the combustion cost is deteriorated due to the engine E being too cold.
In addition, since low-temperature cooling water is introduced into the waste heat recovery unit 36, heat recovery of the refrigerant is not promoted, and the heating efficiency is deteriorated. Therefore, when the temperature below a certain temperature is detected in the thermostat TH, the cooling water Wa flows out to the directly connected pipe 48 and is directly sent to the cooling water pipe 38 without being cooled by the radiator R. .

Here, conventionally, as shown in FIG. 14, the direct connection pipe 48 is connected to the radiator outlet header 50 from the waste heat recovery unit 36, so that the convection from the collision with water in the radiator R as shown in FIG. However, the cooling water Wa is radiated in the radiator outlet header 50 to be cooled, but in the configuration shown in FIGS. 13 and 16, the direct connection pipe 48 is located downstream of the radiator outlet header 50. Since it is connected to the cooling water pipe 38 on the side, the convection does not occur in the radiator outlet header 50, and the problem that the cooling water Wa is cooled does not occur.

Similarly, as a means for causing the cooling water Wa to flow out to the cooling water pump 37 without being cooled by the radiator outlet header 50, as shown in FIG. 17, the radiator outlet header 50 is U-shaped and a trap 50a is provided. On the side, there is also a configuration in which the cooling water pipe 38 is branched from the junction where the cooling water pipe 38 is integrated with the direct connection pipe 48.
Also, in the configuration in which the direct connection pipe 48 is connected to the cooling water pipe 38 on the downstream side of the radiator outlet header 50 as in FIG. 16, as shown in FIG. 18, the junction of the cooling water pipe 38 with the direct connection pipe 48 A check valve 51 is provided between the radiator outlet header 50 and the outlet portion thereof to prevent the low-temperature water in the radiator R from flowing from the radiator outlet header 50 to the junction with the direct connection pipe 48. There is also a method of preventing the cooling water Wa introduced into the cooling water pipe 38 from the directly connected pipe 48 from being further cooled.

The configuration of each part of the outdoor unit has been described above. Next, the configuration of the refrigerant system will be described.
First, referring to FIG. 20 and FIG. 21, the circulation of the refrigerant between the four-way valve 58 and the compressor C in the outdoor unit common to the cooling and heating will be described. The high-pressure gas refrigerant discharged from the discharge port D of the compressor C is supplied to the oil separator 57. Is supplied to the four-way valve 58 through On the other hand, a low-pressure gas refrigerant is supplied from the four-way valve 58 to the compressor C via the accumulator 33.

The flow of the refrigerant during heating will be described with reference to FIG.
The high-pressure gas refrigerant supplied from the compressor C to the four-way valve 58 is first supplied to the indoor unit 59 and condensed and liquefied in the indoor heat exchanger 60. The air is supplied again into the outdoor unit (frame body) 1 through the indoor electronic expansion valve 61, expanded and vaporized by the electronic expansion valve 39 via the liquid receiver 32, and takes heat of vaporization from outside air in the heat exchanger 34. Swell.
Further, the heat of vaporization is taken out by the waste heat recovery unit 36 to be completely vaporized and turned into a low-pressure gas refrigerant, reaches the four-way valve 58, and is thereafter recovered to the compressor C via the accumulator 33. In the figure, V is a check valve, SV is a solenoid valve, ST is a strainer, and STV is a stop valve.

Next, the flow of the refrigerant during cooling will be described with reference to FIG.
The high-pressure gas refrigerant supplied from the compressor C to the four-way valve 58 is supplied to the heat exchanger 34 via the waste heat recovery unit 36 in the outdoor unit, and releases the heat of condensation into the outside air to be condensed and liquefied. It is supplied to a receiver 32.
On the downstream side of the liquid receiver 32, the liquid branches out to a circuit having the electronic expansion valve 39 and a circuit flowing to the indoor unit 59. By closing the electronic expansion valve 39, the liquid flowing out of the liquid receiver 32 is closed. The refrigerant is supplied to the indoor unit 59 without passing through the circuit having the electronic expansion valve 39, expanded by the indoor electronic expansion valve 61, further expanded and vaporized by the indoor heat exchanger 60, and then vaporized from the indoor. Take away heat and cool the room.
Thus, the gas refrigerant vaporized in the indoor heat exchanger 60 flows into the outdoor unit again, reaches the four-way valve 58, and is thereafter recovered by the compressor C via the accumulator 33.

Here, with respect to the electronic expansion valve 39, conventionally, the opening degree is adjusted during heating, the liquid refrigerant sent from the liquid receiver 32 is expanded and sent to the heat exchanger 34, and is fully opened during cooling, Although the liquid refrigerant sent from the side 34 is passed as it is and supplied to the liquid receiver 32, in the refrigerant circuit of this embodiment, the refrigerant is passed only during heating, The valve is closed to prevent the passage of the refrigerant.

On the other hand, conventionally, an injection circuit for feeding liquid refrigerant from between the liquid receiver 32 and the electronic expansion valve 39 to the upstream side of the accumulator 33 in the low-pressure gas refrigerant circuit is provided. This is to lower the pressure (lower temperature) of the low-pressure gas refrigerant on the compressor suction side because the compressor has a bad effect when the discharge temperature of the compressor is high during cooling. A solenoid valve was provided to open the valve when necessary.

However, in the present embodiment, the electronic expansion valve 39 is closed during cooling and is not required for the flow of the main refrigerant flow, and if this is utilized, the injection solenoid valve is not required. That is, on the downstream side of the electronic expansion valve 39, the refrigerant main stream circuit that merges with the circuit from the heat exchanger 34 and the injection circuit IR that merges with the four-way valve 58 upstream of the refrigerant circuit flowing from the indoor unit 59 are branched. In the injection circuit IR, only the check valve V is provided to prevent the flow to the electronic expansion valve 39 side, and the refrigerant is introduced into the injection circuit IR only by the electronic expansion valve 39. Like that. That is, the electronic expansion valve 39 is opened to allow the refrigerant to pass through the injection circuit IR only during cooling and when the compressor discharge temperature is abnormally high.

In the refrigerant circuit according to the present embodiment, as described above, the solenoid valve for injection is replaced with the electronic expansion valve, the merging and branching of the refrigerant circuit, and the arrangement positions of the check valves V, V,. The number of solenoid valves SV is extremely reduced by devising (in the present embodiment, the number is one). Although the solenoid valve SV is automatically controlled by the control box CB, the number of control points is reduced, which leads to a reduction in the number of failures, and the cost for assembling the wire harness and the solenoid valve is also reduced.

Finally, outdoor fan control for improving heating efficiency will be described.
In the outdoor unit, engine waste heat is emitted from the radiator R and the engine room 1b regardless of the driving of the outdoor fan 40. When the outside air is extremely low, when the outdoor fan 40 is operated thereon, the low-temperature outside air is instead taken in, the inside of the outdoor unit becomes abnormally low, and the driving efficiency of the engine deteriorates. Therefore, conventionally, when the temperature drops below a certain temperature (for example, 0 ° C.), the driving of the outdoor fan 40 is automatically stopped to prevent the temperature inside the outdoor unit from being lowered.

However, this does not take into consideration the heating efficiency over the entire operation range of the compressor (minimum discharge capacity MIN to maximum discharge capacity MAX). For example, when the control is performed to stop the outdoor fan 40 at a temperature lower than 0 ° C. The heating efficiency may be improved by operating the outdoor fan 40 even at a temperature lower than 0 ° C, or the heating efficiency may be improved by stopping the outdoor fan 40 even at 0 ° C or higher. This depends on the discharge capacity of the compressor C.

Therefore, as shown in FIG. 22, from the relationship between the outside air temperature (° C.) and the compressor discharge capacity (compression capacity), a boundary where heating efficiency is reduced by driving the outdoor fan 40 is derived and graphed (X in the figure). In the figure, the hatched portions are portions where the heating efficiency is reduced when the outdoor fan 40 is driven. This is mapped and stored in the control unit in the control box CB. If the relationship between the outside air temperature and the compression capacity is in a shaded area, the motor for driving the outdoor fan 40 is turned off; otherwise, the motor is turned on. Control. With such a configuration, optimal heating efficiency is ensured in accordance with the actual outside air temperature and the compression capacity.

It is a front view in the state where the outdoor unit of the engine heat pump was opened to the front. It is a front view of the state where the control box was detached similarly and the whole heat exchange chamber 1a was opened to the front. It is front sectional drawing which shows the assembling method of the underfloor structure of an outdoor unit. It is a top view which shows the E / C unit mounting structure in the engine room 1b. FIG. FIG. FIG. 7 is a plan view of a conventional transformer provided with a rectifier for starting an engine. FIG. FIG. 3 is a plan view of an engine intake system showing a configuration in which a rectifier 28 of an engine starting transformer 27 is disposed at an intake port of an intake duct. It is a perspective view showing the room composition in an outdoor unit. It is a side view schematic of ventilation room 1c. FIG. 4 is an internal plan view of the heat exchange chamber 1a. FIG. It is a figure showing the composition which connected the conventional direct connection pipe 48 to the radiator outlet header 50. FIG. 15 is a diagram showing convection of cooling water in the radiator outlet header 50 and the radiator R in the configuration of FIG. 14. FIG. 3 is a diagram showing a configuration in which a direct connection pipe is connected to a cooling water pipe on the downstream side of a radiator outlet header. It is a figure which shows the structure which formed the trap at the lower end of the radiator outlet header 50, and made the cooling water pipe 38 branch by integrating the other end and the direct connection pipe 49. FIG. 18 is a diagram illustrating a configuration in which a check valve 51 is provided in the configuration of FIG. 17. FIG. 4 is a front sectional view showing an internal configuration of a drain filter DF connected to an exhaust pipe. FIG. 4 is a refrigerant circuit diagram illustrating refrigerant flow during heating. FIG. 4 is a refrigerant circuit diagram illustrating a refrigerant flow during cooling. It is a graph which shows the boundary for performing ON / OFF control of an outdoor fan from the relationship between outside air temperature and compression capacity.

Explanation of reference numerals

E engine C compressor R radiator CB control box TS temperature sensor TH thermostat 1 outdoor unit (frame)
Reference Signs List 1a Heat exchange room 1b Engine room 1c Ventilation room d Fin 2 Underfloor member 2a Cooling air duct room 2b Anti-vibration rubber cooling hole 2c Belt cooling hole 2d Installation leg material 3 Engine room floor material 3a Anti-vibration rubber cooling hole 3b Belt Cooling hole 4 Ventilation room floor material 4a Inclined section 5 Ventilation fan 6 Anti-vibration rubber 7 Unit bracket 9 Drive belt 14 Compressor bracket 34 Heat exchanger 35 Heat exchanger frame 36 Waste heat recovery device 37 Cooling water pump 38 Cooling water pipe 39 Electronic expansion valve 40 Outdoor fan 41 Box bracket 41a Slot 42 Bracket 43 Bolt 44 Bracket 45 Bolt 48 Direct connection pipe 50 Radiator outlet header

Claims (1)

In the outdoor unit 1 of the engine heat pump, the outdoor unit 1 is divided into upper and lower parts, an upper part is a heat exchange chamber 1a in which a refrigerant system and a cooling water system are disposed, and a control box CB is disposed in a front surface inside the heat exchange chamber 1a. The control box CB is provided with an electronic expansion valve 39, etc., at the back thereof, and the control box CB is provided with an elongated front-rear slot 41a. After the control box CB is slid forward in the long hole 41a, the control box CB is horizontally moved by using the last portion of the long hole 41a as a pivot point on one vertical side. An outdoor unit of an engine heat pump, wherein the outdoor unit is rotatable in a direction.

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