Control Box of Outdoor Unit

The present disclosure relates to a control box of an outdoor unit.

There are refrigeration cycle apparatuses such as an air-conditioning apparatus, a chiller, and a water heater, in which a control box having a control substrate accommodated therein is provided inside an outdoor unit. The control substrate is configured to control a compressor, a motor, and other devices of the refrigeration cycle apparatus. In an air-conditioning apparatus described in, for example, Patent Literature 1, an electrical component box including a control substrate is provided in an outdoor unit.

Patent Literature 1 discloses an insect-proof structure to prevent small animals such as insects and geckos from entering the interior of the electrical component box. Patent Literature 1 proposes a technique to prevent the small animals from entering the interior of the electrical component box from an air inlet and an air outlet. In this technique, elliptical air inlets are arranged in alignment with each other with a predetermined spacing between them, and a gap between a box body and a lid body of the electrical component box serves as an air outlet.

The air inlets and air outlet of the electrical component box in Patent Literature 1 are equivalent to a ventilating opening designed to maintain the temperature inside the control box within a predetermined range. Depending on the configuration of a control box, the control box may need to increase the opening area of the ventilating opening to maintain the temperature of electrical components accommodated therein within a range of operation guaranteed temperature. However, there is a problem in that as the opening area of the ventilating opening increases, the small animals are more likely to enter the interior of the control box through the ventilating opening.

The present disclosure has been made to solve the above problems, and it is an object of the present disclosure to provide a control box of an outdoor unit, in which it is possible to reduce entry of small animals such as insects and geckos into the control box through its ventilating opening.

A control box of an outdoor unit according to an embodiment of the present disclosure includes: a housing having a side wall portion; electrical components provided in an interior of the housing; a ventilating opening provided on the side wall portion and communicating with an exterior of the housing; and a lid body provided covering the ventilating opening and having a plurality of first through holes.

In the control box of an outdoor unit according to an embodiment of the present disclosure, the ventilating opening provided in communication with the exterior of the housing is closed by the lid body having the plurality of first through holes. The lid body prevents small animals from easily entering the interior of the control box, and can consequently reduce the entry of the small animals into the control box through its ventilating opening. This can reduce the occurrence of an earth fault due to the small animals coming into contact with the electrical components provided in the control box.

Hereinafter, an embodiment of a control box of an outdoor unit according to the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the embodiment described below, and can be variously modified without departing from the scope of the present disclosure. In addition, the present disclosure includes all combinations of configurations that can be combined among the configurations shown in the embodiment described below. In the drawings below, the same reference signs denote the same or equivalent components, which are common throughout the entire specification. Note that the relative relationship of sizes of the constituent components, the shapes of the constituent components, and the like in the drawings may differ from those of actual ones.

is a perspective view illustrating the interior of an outdoor unitaccording to an embodiment. As illustrated in, the outdoor unitincludes a control box, a compressor, and a transformerinside a cuboid outdoor-unit housingforming the outer shell. One of the plates that are the sides of the outdoor-unit housingis formed removable.illustrates the internal configuration of the outdoor unitwith this plate removed from the outdoor-unit housing.

The control boxaccommodates electrical componentstherein. The electrical componentsinclude electronic components located on a control substrate. Examples of the electrical componentsinclude a microcomputer including a CPU, a ROM, a RAM, and an I/O port and configured to control the compressor. The transformerconverts the voltage. A current whose voltage has been converted in the transformeris used in, for example, the electrical componentsto drive the compressor.

In addition to the control box, the compressor, and the transformer, the outdoor-unit housingfurther has a heat exchanger, a flow switching device, a flow rate control device, and an outdoor fan accommodated therein, although these devices are not illustrated in the drawings. The heat exchanger is configured to allow refrigerant to exchange heat with outside air external to the outdoor-unit housing. The flow switching device is configured to switch between refrigerant flow directions. The flow rate control device is configured to reduce the refrigerant pressure. The outdoor fan is configured to deliver air to the heat exchanger. The compressor, the flow switching device, the flow rate control device, and the heat exchanger are connected by a refrigerant pipe. Illustrations of the refrigerant pipe are also omitted.

The outdoor unitis used as a part of the refrigeration cycle apparatus. For example, the outdoor unitcan be used as a heat pump heat source unit of a heat pump water heater. In a case where the outdoor unitis used as the heat pump heat source unit, the outdoor unitis connected to a hot-water reserve tank through a heat medium pipe. The outdoor unitcan also be used as an outdoor unit of a direct-expansion air-conditioning apparatus. In a case where the outdoor unitis used as the outdoor unit of the direct-expansion air-conditioning apparatus, the outdoor unitis connected to an indoor unit having a load side heat exchanger through the refrigerant pipe. The outdoor unitmay also be used as a part of other refrigeration cycle apparatus such as a chiller, an indirect-expansion air-conditioning apparatus, or a thermal storage device.

Next, with reference to, the control boxof the outdoor unitis explained.illustrates the control boxof the outdoor unitaccording to the embodiment when a ventilating openingis seen from the outside of the control box.illustrates the control boxof the outdoor unitaccording to the embodiment when the ventilating openingis seen from the inside of the control box.illustrates the control boxof the outdoor unitaccording to the embodiment with a lid bodyattached to the ventilating opening.

As illustrated in, the control boxincludes a housingand the ventilating opening. The housinghas a side wall portion. The electrical componentsare provided inside the housing. The ventilating openingis provided on the side wall portion. Since the ventilating openingpenetrates the side wall portion, the exterior of the housingcommunicates with the interior of the housingthrough the ventilating opening.

A part of the side wall portion, where the ventilating openingis provided, has a double structure made up of an outer side-wall portionillustrated inand an inner side-wall portionillustrated in. The outer side-wall portionhas a shape protruding toward the outside of the housing. A space is provided between the outer side-wall portionand the inner side-wall portion

The ventilating openingincludes outer ventilating openingsillustrated inand an inner ventilating openingillustrated in. The outer ventilating openingspenetrate the outer side-wall portion. The inner ventilating openingpenetrates the inner side-wall portion. The outer ventilating openingscommunicate with the inner ventilating openingthrough a space provided between the outer side-wall portionand the inner side-wall portion. The exterior of the housingcommunicates with the interior of the housingthrough the outer ventilating openingsand the inner ventilating openingof the ventilating opening. The space provided between the outer side-wall portionand the inner side-wall portionserves as an air passage(see) of the ventilating opening. The outer side-wall portionand the outer ventilating openingswill be described later in detail with reference to. The inner side-wall portionand the inner ventilating openingwill be described later in detail with reference to.

As illustrated in, the control boxfurther includes the lid bodyprovided covering the ventilating opening, and a sealing materialprovided between the side wall portionand the lid body. The lid bodyis provided to close the inner ventilating openingof the ventilating openingfrom the inside of the housing. The lid bodyis screwed to the inner side-wall portionwith a screw. For example, the screwis an upset head bolt having a hexagonal head portion. The screwis tightened by using a tool such as a spanner or a ratchet wrench. The lid bodyhas a plurality of first through holesand a handle. The lid bodywill be described later in detail with reference to.

The sealing materialis provided to seal a gap between the side wall portionand the lid body. The sealing materialis made of material with elastic and sealing properties. For example, the sealing materialis a foamed sealing material made of ethylene-propylene rubber.

Next, the outer side-wall portionand the outer ventilating openingsare described with reference to.is an enlarged view of the ventilating openingin the control boxof the outdoor unitaccording to the embodiment when the ventilating openingis seen from the outside of the control box. In, four outer ventilating openingsare provided on the outer side-wall portion. However, it suffices as long as the number of the outer ventilating openingis one or more. Hereinafter, when these outer ventilating openingsare collectively referred to as “outer ventilating opening,” this will refer to both a single outer ventilating openingand multiple outer ventilating openings

The outer side-wall portionis a part of the side wall portionthat is formed to protrude toward the outside of the housing. For example, the outer side-wall portionis formed by partially pressing the side wall portionof metal plate into a protruding shape. It is also allowable that an opening is provided on the side wall portion, and a component with a protruding shape is attached to the side wall portionas the outer side-wall portionin such a manner as to close the opening.

The outer side-wall portionincludes a flat part in its outermost protruding portion. The outer ventilating openingis provided on the flat part in the outermost protruding portion of the outer side-wall portion. The outer side-wall portionhas protruding portionsand slitson the flat part in the outermost protruding portion of the outer side-wall portion. The protruding portionand the slitare adjacent to each other. When the outer side-wall portionis viewed from the front, a lower endof the protruding portionoverlaps the slit. For example, the protruding portionis a part of the outer side-wall portionthat is formed by being pressed to protrude toward the outside of the housing. The lower endof the protruding portionprotrudes from the slittoward the outside of the housing. This results in a gap formed between the protruding portionand the slit. This gap formed between the protruding portionand the slitserves as the outer ventilating opening

Next, the inner side-wall portionand the inner ventilating openingare described with reference to.illustrates the control boxof the outdoor unitaccording to the embodiment with the lid bodydetached from the ventilating opening. Similarly to,illustrates the ventilating openingseen from the inside of the control box. As illustrated in, the inner ventilating openingis provided on an upper portion of the inner side-wall portion. In a view, from the inside of the control box, of the ventilating opening, the outer ventilating openingprovided on the outer side-wall portionis invisible due to the inner side-wall portion. The inner ventilating openingand the outer ventilating openingdo not overlap each other in the horizontal direction or the vertical direction.

On the side wall portion, the outer side-wall portionis provided protruding toward the outside of the housing. This results in a space formed on the inner side of the outer side-wall portion. The inner side-wall portionis provided to partition off the space formed on the inner side of the outer side-wall portionfrom the internal space of the housing. The space between the outer side-wall portionand the inner side-wall portionserves as the air passagebetween the outer ventilating opening(see) and the inner ventilating opening

The inner ventilating openingis provided penetrating the inner side-wall portion. With this structure, as illustrated in, a part of the space formed on the inner side of the outer side-wall portionis visible from the inside of the housing. It suffices that the inner side-wall portionis provided in such a manner as to partition off a part of the space on the inner side of the outer side-wall portionfrom the internal space of the housing. In view of that, the inner ventilating openingdoes not need to penetrate the inner side-wall portion. For example, the inner side-wall portionhaving such a size that a part of the space on the inner side of the outer side-wall portionis exposed may partition off the space on the inner side of the outer side-wall portionfrom the internal space of the housing. In this case, an area where the outer side-wall portionis exposed to the inside of the housingserves as the inner ventilating opening

The inner side-wall portionis provided with a screw hole. The screw(see) designed to screw the lid bodyis tightened into the screw hole. It is allowable that the screw holehas a barring shape with a flange formed around the hole. The method for tightening the screwinto the screw holewill be described later with reference to the lid bodyin.

Fitting holesare provided on the inner side-wall portion. In, two fitting holesare provided between which the screw holeis interposed. It suffices that the number of the fitting holeis one or more. The number of fitting holesis not particularly limited. Protrusionsprovided on the lid bodyare fitted into the fitting holes. The protrusionson the lid body, and the relationship between the fitting holesand the protrusionson the lid bodyare described below with reference to.

is a perspective view illustrating the lid bodyaccording to the embodiment.is a side view illustrating the lid bodyaccording to the embodiment. The lid bodyhas a second through hole. The screwis inserted into the second through holeand tightened into the screw hole. This allows the lid bodyto be screwed to the inner side-wall portion

The lid bodyis a metal plate and has a plurality of first through holes. The first through holesare, for example, punch holes formed by drilling holes in the lid bodyof metal plate. The plurality of first through holesare provided to prevent the temperature inside the housingfrom increasing, while ensuring air permeability. However, the number of first through holesis not particularly limited. Each of the plurality of first through holeshas a circular shape. The diameter of the circular shape is equal to or smaller than 3 mm. In, the diameter of the first through holesis smaller than the diameter of the second through holeinto which the screwis inserted. However, it is allowable that the diameter of the second through holeis smaller than the diameter of the first through holes.

The lid bodyhas the handle. The handleis formed by bending a part of the lid bodyof metal plate. As illustrated in, the handleprotrudes from an end portion of the lid bodyperpendicularly to the lid body. The lid bodyis screwed to the inner side-wall portionsuch that the handleprotrudes toward the inside of the housing(see).

The lid bodyhas the protrusions. As illustrated in, the protrusionsprotrude from the flat part of the lid bodytoward a direction opposite to the protruding direction of the handle. For example, the protrusionsare formed by pressing parts of the lid bodyinto a protruding shape. The lid bodyis screwed to the inner side-wall portionwith the protrusionsfitted into the fitting holeson the inner side-wall portion. The protrusionson the lid bodyand the fitting holeson the inner side-wall portionare provided such that the protrusionsare paired with the fitting holes. Since one protrusionon the lid bodyand two fitting holeson the inner side-wall portionare paired, the number of the protrusionsis equal to the number of the fitting holes. The lid bodyis screwed to the inner side-wall portionin a firmly fixed state through pairs of the protrusionsand the fitting holes. With this configuration, the lid bodyis less likely to be displaced from the installation position.

illustrates the two protrusionsthat are provided with the second through holeinterposed between them. Each of the two protrusionsillustrated inis fitted into each of the two fitting holesthat are provided with the screw holeinterposed between them as illustrated in. With this configuration, these two protrusionsand two fitting holesmake two pairs. The lid bodyis fixed to the inner side-wall portionthrough the two pairs of protrusionsand fitting holes, and is thus blocked from rotating when the lid bodyis in a screwed state.

The housinghas been described above as having a double structure in which the side wall portionincludes the outer side-wall portionand the inner side-wall portion. The housinghas the double structure, so that it is possible to provide the outer ventilating openingand the inner ventilating openingat positions where they do not overlap each other in the horizontal direction or the vertical direction. That is, it is possible to provide the outer ventilating openingand the inner ventilating openingat such positions that they are not linearly opposite to each other, so that the interior of the control boxcannot be easily reached from the outer ventilating openingthrough the inner ventilating opening. Even if small animals, rainwater, snow, and the like enter the interior of the outdoor-unit housing, it is still possible to reduce further entry of the small animals, rainwater, snow, and the like into the control box.

As described above, a control boxof an outdoor unitaccording to the present embodiment includes: a housinghaving a side wall portion; electrical componentsprovided in an interior of the housing; a ventilating openingprovided on the side wall portionand communicating with an exterior of the housing; and a lid bodyprovided covering the ventilating openingand having a plurality of first through holes.

In this configuration, the lid bodyis provided covering the ventilating opening. The lid bodyhas the plurality of first through holes, which ensures air permeability of the housingof the control box. This can prevent the temperature inside the housingfrom increasing to such a degree as to affect operation of the electrical components. In addition, the lid bodyis provided covering the ventilating opening, so that small animals such as insects and geckos are less likely to enter the interior of the housingthrough the ventilating opening. That is, the lid bodycan reduce the entry of small animals into the control box, while ensuring air permeability of the control box. When entering the control box, the small animals may come into contact with the electrical components, which may cause an earth fault. However, in the present embodiment, the lid bodycan reduce the entry of the small animals into the control box, and can consequently reduce the occurrence of an earth fault inside the control box.

In the present embodiment, a part of the side wall portionwhere the ventilating openingis provided has a double-wall structure made up of an outer side-wall portionand an inner side-wall portion, a space is provided between the outer side-wall portionand the inner side-wall portion, the ventilating openingincludes an outer ventilating openingpenetrating the outer side-wall portion, and an inner ventilating openingpenetrating the inner side-wall portion, the space between the outer ventilating openingand the inner ventilating openingserves as an air passageconnecting the exterior of the housingand the interior of the housing, and the lid bodyis provided covering the inner ventilating opening

In this configuration, small animals having entered through the outer ventilating openingcannot enter the interior of the housingunless the small animals pass through the air passageand the inner ventilating opening. In order that the small animals enter the interior of the housing, these small animals need to pass through the first through holeson the lid bodyprovided covering the inner ventilating opening. A complicated path leading to the interior of the housingfrom the outer ventilating openingcan further reduce the entry of small animals into the housing.

In the present embodiment, the side wall portionof the housingis a metal plate, the outer side-wall portionhas a slit, and a protruding portionformed by bending a part of the metal plate adjacent to the slitto protrude toward an outside of the housing, and the outer ventilating openingis a gap formed between the slitand a lower endof the protruding portion.

In this configuration, the outer ventilating openingis a gap formed between the slitand the lower endof the protruding portion. With this configuration, when the outer side-wall portionis viewed from the front, an opening part of the outer ventilating openingis covered by the protruding portion. The small animals can enter the outer ventilating openingonly from the lower endof the protruding portion, so that this configuration can further reduce the entry of small animals into the housing.

In the present embodiment, the lid bodyis a metal plate, and each of the plurality of first through holeshas a circular shape with its diameter equal to or smaller than 3 mm. This can block small animals whose length exceeds 3 mm from entering the interior of the housing. This can further reduce the entry of small animals into the housing.

In the present embodiment, the lid bodyhas a handle, and the lid bodyis provided such that the handleprotrudes toward the interior of the housing. That is, with the help of handle, it can be determined which surface of the lid bodyis to cover the ventilating opening. This can prevent the lid bodyfrom covering the ventilating openingin an incorrect orientation. It is possible to easily determine the orientation of the lid bodythat covers the ventilating opening. Consequently, when the lid bodyneeds to be replaced with another, the replacement work can be done quickly.

In the present embodiment, the side wall portionhas a screw hole, the lid bodyhas a second through hole, and the lid bodyis screwed to the side wall portionat the screw holewith a screwinserted into the second through holeon the lid body. With this configuration, it is possible to manufacture the control boxin a state in which the lid bodyhas not yet been attached to the side wall portion, and then attach the lid bodyto the side wall portionafter the control boxis installed in the outdoor unit. Therefore, this gives the control boxand the outdoor unitflexibility in their manufacturing processes and product configurations. The lid bodyis fixed by using the screw, so that the lid bodycan be easily replaced with another by removing the screwusing a tool such as a spanner or a ratchet wrench.

In the present embodiment, the side wall portionhas a fitting hole, and the lid bodyhas a protrusionto be fitted into the fitting hole. With this configuration, the lid bodyis screwed to the side wall portionwith the protrusionfitted into the fitting hole. Therefore, it is possible to prevent the lid bodyfrom being displaced from the installation position. At the time of screwing the lid bodyto the side wall portion, the protrusionis fitted into the fitting holeon the side wall portion, so that the lid bodyis brought into a temporarily fixed state. This facilitates the screwing work. With the help of the protrusion, it can be determined which surface of the lid bodyto cover the side wall portion, and also the vertical orientation of the lid bodycan be determined. This can prevent the lid bodyfrom covering the ventilating openingin an incorrect orientation. It is possible to easily determine the orientation of the lid bodythat covers the ventilating opening. Consequently, when the lid bodyneeds to be replaced with another, the replacement work can be quickly performed.

The control boxof the outdoor unitaccording to the present embodiment includes a sealing materialprovided between the side wall portionand the lid body. In this configuration, the sealing materialseals a gap between the side wall portionand the lid body. This eliminates the possibility of entry of small animals through the gap between the side wall portionand the lid body. There is no gap between the side wall portionand the lid body. This prevents the side wall portionand the lid bodyfrom rubbing against each other despite possible vibrations. This can prevent noise from being generated due to the side wall portionand the lid bodyrubbing against each other.